Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
MSc IN RADIO AND MOBILE COMMUNICATION
SYSTEMS
Final Project Report
Department of Electronic, Communication and Electrical
Engineering University of Hertfordshire
Moveable Light Switch
Report by
Vikas Sharma
Supervisor
Kate William
Date
1st September 2008
Moveable Light Switch
-1-
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
TABLE OF CONTENTS
1. Introduction:
1.1 Background:
1.2 Related work:
1.3 Motivation:
1.4 Amis
1.5 Objectives
2. Existing wireless technology:
2.1 IEEE 802.11/Wi-Fi
2.1.1 IEEE 802.11:
2.1.2 IEEE 802.11b:
2.1.3 IEEE 802.11g:
2.2 802.15.4 Low rate WPAN:
2.2.1 IEEE 802.15.1-2002:
2.2.2 IEEE 802.15.2-2003:
2.2.3 IEEE 802.15.4:
2.3 Bluetooth:
2.4 Zigbee:
2.5Wireless standards:
2.5 1 IEEE 802.11-WLAN/Wi-Fi:
2.5.2 IEEE 802.15.2-Bluetooth:
3. IEEE 802.15.4 WPAN
3.1 IEEE 802.15.4:
3.2 PHY Layer
3.2.1 Receiver Energy Detection (ED)
3.2.2 Link Quality Indication (LQI)
3.2.3 Clear Channel Assessment (CCA)
3.3 MAC Layer
3.3.1. MAC sub layer
3.3.2 Super frame Structure
3.3.3 Network Association
3.3.4 Data Transfer model
3.3.5 Beacon Generation
3.4 Security services:
3.5 Properties of 802.15.4
3.5.1 Transmitter and Receiver
3.5.2 Channels
4. Zigbee Specification:
4.1 Zigbee Overview:
4.2 Network Topologies
4.2.1 Star Topology
4.2.2 Peer-to-peer Topology:
4.2.3 Cluster-tree Topology
4.3 ZIGBEE DEVICES:
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
4.3.1 PAN (Personal Area Network) Coordinator
4.3.2Full Function Device
4.3.3 Reduced Function Device
4.4 The ZigBee Protocol
4.5 Network layer
4.6 Application layer:
4.6.1 Application Support Sub layer (APS)
4.6.2 Application Framework
4.6.3 ZigBee Device Object (ZDO)
4.7 ZigBee Implementation: Hardware and Firmware Considerations
4.7.1 Chipset reference designs
4.7.2 Chipset custom designs
4.7.3 Design-in modules
4.8 ZigBee Implementation: Profile Considerations
5. Selection of Devices:
5.1 XBee and XBee-PRO Product Comparison
5.2 Modules and modems:
5.2.1 Radiocraft:
5.2.2 Meshnetics:
5.2.3 Impulse:
5.2.4 Microchip:
5.2.5 2.4 GHZ 802.15.4 development kit:
5.2.6 Jennic:
5.2.7 RFM (Cirronet):
5.2.8 ZigBee and 802.15.4 (2.4 GHz):
5.2.9 Digi (MaxStream):
5.3 Hardware versions
5.3.1 Antennas
5.3.2 PRO / Standard version
5.4 Firmware versions
5.4.1Communication Interface:
5.4.2 Device type / purpose:
5.4.3 Firmware capabilities:
5.4.4 Coordinator:
5.4.4 Router
5.4.5 End device
5.5 Mode of Operation:
5.5.1 Transmit Mode
5.5.2 Receive Mode:
5.5.3 Command Mode:
5.5.4 Sleep Mode:
5.6 XBee Series 2 OE M RF Modules
5.7 PIC 16F88:
5.8 Rs232
5.9 Usb
5.10 MPLAB Integrated Development Environment (IDE)
5.11 XBee/XBee-PRO Code Development
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
5.11.1Configuring the XBee from X-CTU Software
5.11.2 Configuring the XBee from Terminal
6. Result
6.1 Experiment1:
6.1.1Result:
6.2 Experiment 2:
6.3 Experiment 3:
7. Conclusion:
Future Works
References:
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
List of figures
3.1
4.1
4.2
4.3
Super frame structure
Three different topology
ZIGBEE Devices
Architecture of ZIGBEE
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
6.1
6.2
6.3
6.4
6.3
Antena options for Xbee Modules
Pin Diagram of PIC16F88
Pin description of RS 232
For the setting the Baud rate
For the setting the Baud rate
For the setting the Baud rate
For the setting the Baud rate
Configure the Xbee from terminal
Configure the Xbee from command
For range test using loop back filter
Connection of moveable light switch
Sending data by Xbee light switch
Receiving data by Xbee for light input
Interfacing microcontroller with Xbee
List of Tables
2.1
3.1
3.2
3.3
3.4
4.1
5.1
5.2
5.3
5.5
5.6
6.1
6.2
6.3
6.4
Moveable Light Switch
Comparison of different wireless technology
Frequency Bands and data rates
IEEE 802.14.4 packet structure
High level characteristics
Comparison of IEEE 802.15.4 frequency bands
Comparison of Zigbee devices at the network layer
Specification of Xbee and Xbee pro
Issues of Zigbee and Znet
Pin description of RS 232
Pin. Description of USB
Feature pf PIC 16F88
Loop back filter
Connection for moveable light switch
Sending data by Xbee as light switch
Receiving data by Xbee for light
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
1. Introduction:
The goal of this project was to build the moveable light switch using zigbee wireless
technology that offers a seamless and cost-effective solution to the problem of gathering
remote sensory data. A good example of where such a system could d be particularly useful
is home automation and building. Since all of the data is sent wirelessly so Xbee module has
been used to transmit/receive the data. The installation consists of setting up the nodes,
attaching the switch at the input and Light at the outputs to the module, and then sending
and collecting the data from one end to other end wirelessly.
Every day the need of Interconnection between wireless and hand held devices is increasing
for making life easier, more flexible and more efficient. Cable infrastructures are not useful in
an environment where everyone has to move all the time and wireless connection can be used
every time and everywhere, with or without predefined infrastructure. There is another need
which has been considered that, low power consumption for the longer battery life time.
There are many short range communication protocols are available such as Bluetooth, ZigBee and Wireless Local Area Network (WLAN), which can be used for transmission
distances from 10m up to 100m.
In order to get a long network lifetime, the nodes must turn their device off as much as
possible. In a multihop communication, the receiving nodes should be awake when a packet
comes from sending node. [1] an explosive growth has been seen over the last decades in
wireless technology. The different wireless standard which is coming now a day has made the
development of wireless application easy.
One of those technologies is the IEEE 802.15.4 specification. The IEEE 802.15.4 focus on
energy efficiency, flexibility and low cost of personal area networks (PAN) in sending data
from one location to another. [2]
Now a day’s Wireless technology is becoming more and more popular than ever because it
gives the ability to user to move and user does not have to stick with cables all time. A great
deal of work is being done in the field of Wireless technologies.
It has been accepted that the low cost wireless solution are feasible and acceptable after the
802.11 for wireless local area network (WLAN) and cellular phone networks have proved
that low cost wireless solutions are feasible and acceptable. Now because of advancement in
technology there is a need of more and more wireless personal area network and these
WPAN are different than WLAN it requires short range ,low data rate and low inexpensive
solution to network within a small area , there are many solutions which address these
needs, but either they are expensive or incompatible between different manufacturers. The
IEEE 802.15.4 has emerged as new standard for LR-WPAN focusing on low cost and less
complicated solution. This can be used in applications such as home/office automation,
Industrial sensors and control, distributed sensor networks and environment monitoring [3].
The ZigBee alliance, is an group of companies and they are working together to provide
Products based on ZigBee standard for monitoring and control, and made this standard more
popular. The upper layer is defined by the zigbee standard that is built on the IEEE 802.15.4
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
standard. The main aim of the ZigBee alliance is to replace every Switchbox, electrical outlet
and various sensors in a building by wireless nodes which Communicate with each other.
This standard is being popular and adopted by the industry.
1.1 Background:
In 1897, Guglielmo Marconi first developed radio’s ability to give continuous contact
With ships sailing across the English Channel. Since then, much advancement has been seen
in the field of wireless communications. Number of experiments has been carried out by
different researchers to make use of electromagnetic waves for carrying.
In 1946 the first public mobile telephone service was launched in the United States for
distance up to 50 Km. but these services were used for half duplex mode. By the mid 1960s,
because of advancement in technology the IMTS (Improved Mobile Telephone Service) were
introduced which offered full duplex service.
In the 1960s, the concept of dividing the coverage area in to small cells was introduced by the
AT&T Bell Laboratories and other telecommunication companies.
In 1993 the IS-95 the next digital system was launched in 1993 and this used CDMA.
In 1995 the further improvements and advancement in technology brought the PCS (Personal
Communication Services).
Today there are more than 60 million wireless customers exists, according to the Cellular
Telecommunications Industry Association (CTIA).[4],041372
ZigBee got its name from the way bees zig and zag while tracking between flowers and
relaying Information to other bees about where to find Resources.
ZigBee is a new wireless standard in wireless technology and it focuses on standardizing and
enabling interoperability of products. ZigBee provides a short-range which is suitable for cost
effective networking capability. Zigbee has been introduced with the emphasis on low-cost
battery powered applications.
1.2 Related work:
Several companies are selling Zigbee stack and most of them are selling with a
device.[23],[5] Paper “titled on use of IEEE 802.15.4 to enable wireless sensor networks in
building automation” gives the detail about effects on building maintenance, energy
consumption, safety and security.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
1.3 Motivation:
IEEE 802.15.4 is new standards in wireless communication technology and lots of research is
going on the use of different routing protocols, efficient energy use and coexistence issue of
IEEE 802.15.4.Most of the application use the embedded device. According to the Zigbee
promoters in the next few years, Zigbee product will be the important part of every single
house because of its simplicity and low cost feature.
1.4 AIMS:
The main aim of the project is to create a wireless link and to develop a wireless switch using
short range Zigbee technology suitable for home application.
1.5 Objectives:
Objectives of this project include design and construct hardware for switch input and light
and make it work as remote control of the light via switch.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
2. Existing wireless technology:
In wireless technology many standards has been specified that addresses mid to high data
rates for voice, PC LAN’s, Video etc.
There is no wireless network which meets the unique requirement of devices such as sensors
and control devices. Both these sensors and control devices are mostly used in industry and
home automation with low data rates and need of very low energy consumption.
More and more new wireless technology are being developed due to fast development in
communication field especially in wireless communication which gives the user ability to use
the technology without cables.
In the recent years there has been seen a development in wireless technology such as Wi-Fi
for (WLAN), Bluetooth, Zigbee for (WPAN), Wimax for (Wireless MAN) and all these
different technology playing an important role in the communication field.
There are many wireless technologies which are being developed now days. Table shows a
comparison of wireless technology based on their frequency range, power consumption,
performance etc.
2.1 IEEE 802.11/Wi-Fi
Whenever we talk about wireless then name of WLAN come first .IEEE 802.11 is a set of standards
for WLAN. Evolutions of WLAN are as follows:[6]
2.1.1 IEEE 802.11:
IEEE 802.11 supports direct sequence spread spectrum and frequency hopping spread
spectrum(FHSS) modulation scheme and it specifies data rates 1 & 2 mega bit per second and
then very soon it was popularized by IEEE 802.11b
2.1.2 IEEE 802.11b:
IEEE uses same modulation scheme as original version with maximum data rate is 11 Mbps
because it is operated in 2.4 GHz band.
2.1.3 IEEE 802.11g:
IEEE 802.11.g was introduced after 4 years of IEEE 802.11.b. and it gives a high data rate up
to 54 MBps and uses the modulation technique OFDM.
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Wireless Parameter
Bluetooth
Wi-Fi
Zigbee
Frequency band
2.4 GHz
2.4 GHz
2.4 GHz
Physical/MAC layers
IEEE 802.15.1
IEEE 802.11b
IEEE 802.15.4
Range
9m
75- 90 m
Current consumption
60 mA (Tx mode)
Raw data rate
723 Kbps
400 mA (Tx mode)
20 mA (Standby
mode)
11 Mbps
Indoors: up to 30 m
Outdoors (line of
sight):
up to 100
25-35 mA (Tx mode)
3 μA (Standby mode)
Protocol stack size
250 KB
1 MB
Typical network join
time
>3 sec
variable, 1 sec
typically
Interference
avoidance
method
FHSS
(frequency-hopping
spread spectrum)
DSSS
(direct-sequence
spread
spectrum)
DSSS
(direct-sequence
spread
spectrum)
Minimum quiet
bandwidth required
Nodes per network
15 MHz (dynamic)
22 MHz (static)
3 MHz (static)
7
32 per access point
64 K
Number of channels
19
13
16
250 Kbps
32 KB
4 KB (for limited
function end devices)
30 ms typically
Table 2.1 Comparison of different wireless technology[6]
2.1.3 IEEE 802.11g:
IEEE 802.11.g was introduced after 4 years of IEEE 802.11.b. and it gives a high data rate up
to 54 MBps and uses the modulation technique OFDM.
2.2 802.15.4 Low rate WPAN:
Network which is used for connecting personal devices in a short range by using wireless
connection is called Personal area network.[6]
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
WPAN is becoming more and more popular because PCs, PDAs, peripherals, cell phones,
Bluetooth, earphone and wireless mouse exist in our daily life.
The main challenge before WPAN is low cost and low power consumption irrespective of
transmission range and rate which is just opposite to WLAN which targets at higher data rate
and longer range.
Standard
802.11a
802.11a
802.11a
802.11a
802.15.1
802.15.1
802.15.1
Frequency
5 GHz
2.4 GHz
2.4 GHz
2.4/5 GHz
2.4 GHz
868/915MHz
2.4 GHz
1 THz
Data Rate
54 Mbps
11 Mbps
54 Mbps
248 Mbps
3 Mbps
Range
Type
40 Kbps/250 Kbps
120 m
140 m
140 m
250 m
100 m
75 m
LAN
LAN
LAN
LAN
PAN
PAN
>1Gbps
10 m
BAN
Table 2.2 Comparison of different wireless standards [6]
IEEE 802.15 serial standards are established by IEEEE 802.15
2.2.1 IEEE 802.15.1-2002:
The lower layer of Bluetooth transport layer (l2CAP, LMP, Baseband & radio) has been
defined by this standard and it has also reviewed the Bluetooth MAC (L2CA, PLMD &
baseband) & physical (radio).[7]
2.2.2 IEEE 802.15.2-2003:
It has been established for analyzing the coexistence of WPAN and WLAN (802.11).The
IEEE 802.15.2 has developed a model to quantify the interference of WLAN & WPAN
2.2.3 IEEE 802.15.4:
The MAC (medium access control sub layer) & PHY layer has been specified by this
standard for low rate wireless personal area network. Zigbee is built on the IEEE 802.15.4
2.3 Bluetooth:
Bluetooth is known for short range connectivity. for simultaneously voice and data and
multipoint communication, Bluetooth has been designed .range of Bluetooth is 10m which
can be increased of up to 100m by using an amplifier.[7]
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Any Bluetooth system has four basic parts

RF: RF is used for receiving and transmitting the data and voices.

Baseband/link control: it is used to process the transmitted or received data.

Link management S/W: it manages the transmission
Basics characteristics of Bluetooth are:




It operates at 2.4 GHz band
It uses FHSS for avoiding interference
It supports up to 8 devices in a piconet (1 Master & 7 slaves)
Pico net can make scatter net[8]
2.4 Zigbee:
Zigbee has been designed to replace individual remote control. It has been created to satisfy
the market need for a cost efficient that supports low data rates, low power consumption.
Zigbee product can operate in three different frequency band 2.4 GHz (worldwide), 902-928
MHz (Americas) & 868 MHz (Europe) with direct sequence spread spectrum modulation
scheme.
Zigbee is a wireless standard similar to Bluetooth. It has been specified by IEEE 80215.4
standard. Zigbee operates in three different frequency band 868 MHz, 915 MHz & 2.4 GHz
ISM bands.[7][2]
2.5Wireless standards:
2.5 1 IEEE 802.11-WLAN/Wi-Fi:
WLAN is also called Wi-Fi; it is technology for data communication .WLAN operates on 2.4
GHz & 5MHz ISM frequency bands. It has been specified by much different variation like
802.11a/b/g/n depending on the speed and range.
2.5.2 IEEE 802.15.2-Bluetooth:
Bluetooth has been specified by IEEE 802.15.1 standard. It is the basis of wireless
communication technology for short range communication. It is suitable for small and low
cost devices with low power consumption. Bluetooth operates at 2.4 GHz frequency band as
IEEE wireless LAN. In order to prevent interference both technology use different signalling.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
3 IEEE 802.15.4 WPAN
3.1 IEEE 802.15.4:
The 802.15.4 standard has defined the physical (PHY) and medium access control (MAC)
layer protocols which fully support simple sensor devices that consume minimal power and
work in an area of 10m or less. The range can be extended beyond 10m but this need to have
additional energy to operate. This standard allows two types of topologies such as a simple
one hop star or a Self configuring peer-to-peer network.
In terms of communicating wireless the 802.15.4 operates in three license free (ISM)
frequency band The three frequency band of operation has been defined by IEEE 802.15.4
and these are 2 .4 GHz, 915 MHz and 868 MHz Each frequency band is used for different
channels e.g. The 2.4 GHz frequency band provides a total of 16 channels (channel 11-26),
915 MHz provides 10 channels (channel 1-10) and 868 MHz provides 1 channel (channel
0).The frequency of the operation specifies bit rate.250Kbps can be achieved from 2.4 GHz
,40Kbps from 915 MHz and 20Kbps from 868MHz. The throughput of actual data is
achieved less than Specified bit rate because of packet overhead and processing delays.[22]
Spreading parameter
Data parameter
Chip
rate(Kchip/s)
Modulation
Bit rate
Kb/s
Symbol
rate(Symbol/s)
868-868.6
300
BPSK
20
20
902-928
600
BPSK
40
40
2000
O-QPSK
250
62.5
Frequency
PHY(MHZ) Band
868/915
2450
24002483.5
Table 3.1
Frequency bands and data rates. [22]
The127 bytes are the maximum length of an IEEE 802.15.4 MAC packet .the header bytes
and a 16-bit CRC value is included in each packet. The 16-bit CRC values used to verify the
frame integrity. IEEE 802.15.4 also uses an Acknowledged data transfer method, and all the
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
frames are acknowledged at the receiver by using special acknowledge flag set. Transmitter
resend the packet if it does not receive an acknowledgement within a certain amount of time.
The transmitter retries for a fixed number of times and even if does still does not get an
acknowledgment then it declares an error. [22][14][16]
But at a time only one channel is used for communication and the additional channel give the
flexibility to switch to another channel when the existing channel does not work.
There are two types of devices are available in 802.15.4.
One is called full-function device (FFD) while the other is reduced-function device (RFD).
RFD is crude device and these devices support application such as a switch or sensor.
Network is controlled by FFD device while RFDs is used to communicate with FFDs.The
protocol use either 16 bit short address or 64-bit IEEE addresses.[22]
3.2 PHY Layer
The physical (PHY) layer plays an important role in communication. Basically it is used for
data Transmission and reception, channel sensing, link quality determination, channel
selection, and node state setting. It communicates directly with the wireless channel, and then
supplying information to and from the upper layers. This function is essential for the carrier
sense multiple accesses with collision avoidance (CSMA/CA) procedure. Every node has to
determine the channel first whether the channel is free or not before to reserve the cannel.
The PHY protocol does energy detection (ED) scan and clear channel assessment (CCA) on
the channel for detecting any ongoing activities and then it transfers the results to the MAC
layer. When threshold value of activity levels is detected exceeded then the channel is
considered busy. Link quality is an another important factor which helps both Upper layers
protocols (MAC and network) to decide before to use a particular channel because link
quality contains the information about noise and electromagnetic signal which can affect the
network performance. If any channel is not available for communication then there are 26
other channels available under 802.15.4. zigbee pdf, 01200605
PHY PROTOCOL DATA UNIT
Preamble
Start of packet
Delimiter
Length Field
PHY layer payload
PHY service data unit (PSDU)
4 bytes
4 bytes
4 bytes
2-1274 bytes
Table3.2 IEEE 802.15.4 Packet Structure[22]
Physical layer of IEEE 802.15.4 standard uses the direct sequence spread spectrum (DSSS)
technique by which low cost digital IC can be used. Receiver sensitivity for 2.4 GHz band is
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
-85dBm has been specified by the IEEE 802.15.4 and -92 dBm for the 868/915 MHz band.
Practical implementations are expected to improve this requirement.
PHY layers uses a common packet structure, and Each packet, or PHY protocol data unit
(PPDU), contains a preamble, a start of packet delimiter, a packet length, and a payload field,
or PHY service data unit (PSDU). The 32-bit preamble is used for acquisition of symbol and
chip timing. The IEEE 802.15.4 Payload length can be varied from 2 to 127 bytes. This
structure is shown in Figure 3.2[22][12]
3.2.1 Receiver Energy Detection (ED)
The receiver energy detection (ED) measurement is used by a network layer for channel
selection algorithm. The received signal power is estimated within the bandwidth of an IEEE
802.15.4 channel. The ED time is kept to equal to 8 symbol periods. The ED result is
reported as an 8-bit integer ranging from 0x00 to 0xff. When ED value (0) is received then it
indicates that received power less than 10dB above the specified receiver sensitivity.[22]
3.2.2 Link Quality Indication (LQI)
When a packet is received, then PHY layer sends the PSDU length, PSDU itself and link
quality (LQ) in the PD-DATA indication primitive. The LQI measurement is used for finding
the strength and/or quality of a received packet. The measurement can be done using receiver
ED, a Signal-to-noise estimation or a combination of these methods. The result of LQI result
is used by the network or application layers. [11]
The LQI result is reported as an integer ranging from 0x00 to 0xff. The minimum and
maximum LQI values are associated with the lowest and highest quality IEEE 802.15.4
signals which are detected by the receiver and LQ.[22][16]
3.2.3 Clear Channel Assessment (CCA)
The clear channel assessment (CCA) is performed according to at least one of the following
three Methods:

Energy above threshold: In this case, busy medium is reported by the CCA when
energy is detected above the ED threshold.

Carrier sense only: In this case, a busy medium is reported by the CCA when signal
is detected with the modulation and spreading characteristics of IEEE 802.15.4 and
the detected signal may be above or below the ED threshold.

Carrier sense with energy above threshold: In this method, a busy medium is reported
by CCA when signal is detected with the modulation and spreading characteristics of
IEEE 802.15.4 with energy above the ED threshold.[8]
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
3.3 MAC Layer
This layer is used to provide an interface between upper layers and the PHY layer. It plays an
important role in handling channel access, link management, frame validation, security, and
nodes synchronization. In a beaconless mode which uses unslotted CSMA/CA method, in this
mode, the PAN handles the association and disassociation of devices and provides the short
address when 64 –bit IEEE addresses is not used. The CSMA/CA method is used for
accessing the channel but RTS/CTS handshake is not included in this method. This method
accesses the channel and if it is free then it allows the data packet to transmit. Otherwise it
uses back off (short duration of time) for certain periods and then channel is accessed again.
Collision can occur without using the RTS/CTS handshake, because of hidden nodes data can
be sent to same destination at the same time.
The MAC layer uses various mechanisms such as frame acknowledgment association,
administering device security and scheming the guaranteed time slot mechanism for
improving link reliability. MAC layer uses different methods for improving the link
reliability such as frame acknowledgment and retransmission and data verification using 16bit CRC, along with CSMA/CA.
The MAC sub layer gives two different services to the higher layers. The MAC data service
is accessed through the MAC common part sub layer (MCPS-SAP) which contains three
primitives and the MAC management service accessed through the MAC layer management
entity (MLME-SAP) which contains 28 primitives.
The LR-WPAN standard allows the optional use of a Super frame structure which is provided
in LR-WPAN standard and used for applications that require reserved Bandwidth to
guarantee communication. PAN coordinator decides the format of the super frame. The super
frame is made up of 16 equally sized time slots which are grouped in two sections: the
contention access period (CAP) and the contention free period (CFP). PAN coordinator
assigns the time slots for the CFP which are called guaranteed time slots (GTS). A pictorial
of the Super frame structure is shown in Figure 3.4.
802.11b WLAN
802.15.1
WPAN
802.15.4
LR-WPAN
Range
~100 m
~10 - 100 m
10 m
Raw data rate
11 Mbps
1 Mbps
Power consumption
Medium
low
<=
0.25
Mbps
Ultra low
Table3.4 IEEE 802.15.4 High Level Characteristics [6]
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
A summary of the high-level features of the IEEE 802.15.4 is shown in Table 3.4. The motive
behind low-cost and low-power, IEEE 802.15.4 is to provide applications in the fields of
industrial, agricultural, vehicular, residential and medical sensors and actuators and address
applications where current WPAN solutions are too expensive The IEEE 802.15.4 standard
has been designed as standard which can be used in a wide variety of applications which
require simple wireless Communications over short-range distances with limited power.[6]
3.3.1. MAC sub layer
The IEEE 802.15.4 medium access control (MAC) sub layer is used to control the access
over radio channel which employs the CSMACA method. When lower throughput than
threshold is detected by the upper layer then MAC layer is asked to perform the energy scan
over the available channel. Based on the detected energy, the upper layers will switch to
the channel with the lowest energy.
The IEEE 802.15.4 performs the energy scan by the use of a clear channel assessment
procedure. This can be performed by following either simple in-band energy detection above
a threshold or an IEEE 802.15.4 carrier detection or a combination of both. The 802.15.4
MAC is also responsible for flow control via acknowledged frame delivery, frame validations
as well as maintaining network synchronization.[22]
Fig 3.1 Super frame structure [22]
Moveable Light Switch
- 17 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
3.3.2 Super frame Structure
LR-WPAN allows the optional use of a super frame structure. The coordinator defines the
format of the super frame and divided into 16 equally sized slots. In the first slot of each
super frame, beacon frame is sent. The coordinator can turn off the beacon transmission if
coordinator wishes to not to use the super frame structure. The beacons are used for the
synchronization of the attached devices, for identifying the PAN.
The super frame can be in an active and an inactive position. When it is in the inactive
position, then Coordinator does not interact with its PAN and enter in to a low-power mode.
The active position consists of contention access period (CAP) and contention free period
(CFP). [22]
3.3.3 Network Association
ZigBee networks can be used as an ad-hoc, it means that a new network is formed and
unformed when needed. In a star network configuration, end devices have to search for a
network before to transfer any data. A new network is formed by a coordinator. After
forming a network coordinator searches for other coordinators nearby and if it does not find
any coordinator then it makes it own network. And then selects a unique 16-bit PAN ID.
As soon as new network is formed, one or more end devices can be allowed to join with the
network. The decision is taken by coordinator to allow or disallow the new association. There
is possibility that one network may overlap because of the physical changes and then PAN ID
conflict occurs. Once joining to a network, an end device can disassociate itself from the
network by performing the disassociate procedure. If required, then a coordinator
itself can force end device to do disassociate procedure to force for leaving the
network.[23][22]
3.3.4 Data Transfer model
The data can be transferred in to three different ways from a coordinator to a device, from a
device to a coordinator and between two peer devices. The mechanism of these transfers
depends on whether the beacon is being used in the network or not.When a beacon is not
enabled and device wants to transfer a data then it transmits its data frame, using the
unslotted CSMA-CA, to the coordinator.
In case when beacon is enabled and a device wants to send data to a coordinator, then they
have to first listen for the network beacon. When they find the beacon then synchronization
with super frame structure is done and at the same time, device sends its data frame, using
slotted CSMA-CA, to the coordinator.
In a non-beacon star network, when an end device wants to send a data frame to coordinator
then it has to wait for the channel to become idle. As soon as it detects an idle channel
condition, it immediately transmits the data to the coordinator. In case if a coordinator
Wants to send data to an end device, then data is kept in the transmit buffer until the end
device polls for the data. This method is used to make sure that the receiver of the end device
is still turned ON and it can receive data from the coordinator.
Moveable Light Switch
- 18 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
In a peer-to-peer network, either each node has to keep their receiver ON all the time or they
follow the time interval period during which they will switch ON their receivers. This
procedure makes sure that transmitted data is received by the receiver end device.
But the receiver end device should poll for the coordinator instead of keeping its receiver ON
all time which will make the end device low power requirement. Depending on application,
end devices can spend most of their time in sleep mode and can wake up periodically for
transmitting or receiving the data. The disadvantage of this method is that coordinator will
have to keep all data frames in its internal buffer until the end device wakes up and polls for
the data. In case there are more end devices in a network that sleep for log time, it means that
the coordinator will have to keep the data frame for that long period. In other words it will
increase the coordinator RAM requirement Depending on the number of nodes and rate of
data frame exchanges.[23][22]
3.3.5 Beacon Generation
The FFD can be in a beaconless mode or can begin beacon transmissions either as the PAN
coordinator or as a device, depending on the parameter which is set by MLME-START
request primitive. An FFD which is not the PAN coordinator first associate itself with a PAN
then starts transmitting beacon frames. [23]
3.4 Security services:
There are four basic security services which are defined by the MAC layer:

Access Control: This security service allows the MAC to choose the devices which it
is going to communicate with, it is based on the MAC address of the received frame.

Data Encryption: This security service is used to encrypt the MAC frame for data
privacy protection based on the use of symmetric key Cryptography.

Frame Integrity: This security service enables a receiving device to observe the
changes of a message (deliberate or inadvertent) using a cryptographic message
integrity code (MIC). The MIC is generated by the MAC layer and appended in to the
MAC frame.

Sequential Freshness: This security service is used to append the ordered sequence
of values to the MAC frame for preventing replay attacks attacker captures the old
message without cryptographic key and then it is re-sent later. [23]
3.5 Properties of 802.15.4
Table summarizes the properties of IEEE 802.15.4 in two of the ISM frequency bands: 915
MHz and 2.4 GHz.
Moveable Light Switch
- 19 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Property
Description
Raw data bit rate
Prescribed value
915 MHz
2.4 GHz
40 kbps
250Kbps
Transmitter output
power
Receiver
sensitivity
1 mW = 0 dBm
-92 dBm (<1% packet error -85 dBm (<1% packet error rate)
rate)
Transmission
range
Indoors: up to 30 m; Outdoors: up to 100 m
Latency
15 ms
Channels
10 channels
16 channels
Channel
numbering
1 to 10
11to 26
Channel access
Modulation
scheme
CSMA-CA and slotted CSMA-CA
BPSK
0-QPSK
Table 3.5 Comparison of IEEE 802.15.4 Frequency Bands [20]
3.5.1Transmitter and Receiver
There are two determining factor for the strength of the signal and its range and these are the
power output of the transmitter and the sensitivity of the receiver. There are some other
factors which make the signal noisy .Signal range is increased with the higher the transmitted
power. While receiver sensitivity is used to determine the minimum power for the receiver to
receive the signal. Both of these values are described using dBm (decibels below 1 mw), a
relative measurement which compares two signals with 1 mw is used as the reference signal.
Higher sensitivity equals to the large negative dBm number.[22][23][20]
3.5.2 Channels
The 2.4 GHz band can be used world-wide out of three available ISM frequency band . The
868 MHz band only operates in the EU and the 915 MHz band is only for North and South
America. If global interoperability is not a requirement, the relative 915 MHz band in nonEuropean countries can be an advantage for some applications.
Moveable Light Switch
- 20 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
For the 2.4 GHz band, 802.15.4 has specified that the communication should occur in 5 MHz
channels ranging from 2.405 to 2.480 GHz.[22][23]
4. Zigbee Specification:
4.1 Zigbee Overview:
ZigBee is used to describe a standardized wireless protocol for personal area
networking(“WPAN”) The zigbee protocol is the result of ZigBee Alliance, which is a group
of more than 70 companies who are working together to create and promote the new
standard in wireless technology .
ZigBee has been introduced by the ZigBee Alliance, which is an organization of
manufacturers and working to develop a new networking technology for small, ISM-band
radios which can be best fit to simple industrial and home end devices into wireless
connectivity.[8][10]
In December 2004 the ZigBee specification was finalized and now a day’s products from
ZigBee standard are coming to market. ZigBee has been designed to provide the low-cost,
low-power, low-data rate wireless mesh technology. [9][11]
ZigBee is different from other wireless standards because it has been designed to satisfy the
unique need of applications which require low cost, low power wireless Connectivity.
The main focus of zigbee is to provide low data rate, low duty cycle connectivity, a market
Segment which has not been serviced well by existing standards. Zigbee is known as a
standard because of its interoperability between devices manufactured by different
companies.[8][9]
ZigBee is a hardware and software standard which is built on the IEEE 802.15.4 standard.
This important standard defines the hardware and software, hardware which is defined by
IEEE 802.15.4 and includes physical (PHY), and Medium Access Control (MAC) layers. The
zigbee Alliance defines Network (NWK) and application (APL) layer which works together
with hardware standard and complete standard is called Zigbee stack. 12
4.2 Network Topologies
Figure 4.1 shows 3 different types of topologies that ZigBee supports: star topology, peer-topeer topology and cluster tree topology.
4.2.1 Star Topology
In the star topology, The PAN coordinator is connected through mains powered while the end
devices are most likely battery powered. Star topology can be used in many applications such
as home Automation, personal computer (PC) peripherals, toys and games.[7]
Moveable Light Switch
- 21 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
When FFD is activated for the first time, it can form its own network and become the PAN
coordinator.
A star network configuration consists of one coordinator node which acts as a “master” and
one or more end devices and these end devices act as “slaves”. The coordinator acts as Full
Function Device (FFD) which is used to implement a larger set of ZigBee services. The end
devices can be used as FFD or a Reduced Function Device (RFD). An RFD is considered as a
smallest and simplest ZigBee node, which is used to implement a small set of ZigBee
services.
In a star network, all end devices can send data to coordinator only. If any end device has to
send data to another end devices, then data is sent to the coordinator and the coordinator, is
used to forward the data to receiver end device.[13][14][15]
Fig 4.1
Three different topology[15]
4.2.2 Peer-to-peer Topology:
There is also one PAN coordinator in this topology. The difference between star and this
topology is that, any device can communicate with any other device as long as they are in
range of each other. A peer-to-peer network can be ad hoc, self-organizing and self-healing.
It is used for Applications such as industrial control and monitoring, wireless sensor
networks, asset and inventory tracking in this topology, message can be sent to any device
from any device of the network and provides reliability by multipath routing.[14][15]
Moveable Light Switch
- 22 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
4.2.3 Cluster-tree Topology
Cluster-tree network is a similar to peer-to-peer network. Any of the FFD can be used as a
coordinator and it gives synchronization services to other devices and coordinators.FFD
which becomes the coordinator and forms the first cluster by making itself as the cluster head
(CLH), any device which wants to join the network sends a request to CLH.if the request is
accepted then it is added as a child device by the CLH in its neighbour list and the end device
will add the CLH as its parent in its neighbour list. The cluster and mesh network are also
called a multi-hop network, because these network can send packet to multiple networks, but
the star network is only a single-hop network.[15][7]
A ZigBee network can also work as a multi-access network; it means that all nodes in the
network can use the resources equally.
4.3 ZIGBEE DEVICES:
The three different kinds of devices have been identified in zigbee specification and these are
follows as: :4 pdf



PAN (Personal Area Network) Coordinator
FFD (Full Function Device)
RFD (Reduced Function Device)
4.3.1 PAN (Personal Area Network) Coordinator
PAN coordinator is used to form the network, stores the information of the nodes in the
network and manages the network when network is initiated and data is routed to different
nodes with PAN coordinator.
In a network there can be only one PAN coordinator. It can communicate with any device in
the network.PAN coordinator can work in all three topologies star, mesh and cluster tree
topologies.. [8] [4] PAN coordinator which manages and handles one network with all the
nodes in that network by sending and receiving packets.[16][15]
4.3.2Full Function Device
Full Function Device (FFD) as shown in figure, is capable of becoming a network
Coordinator. FFD can be used with PAN coordinator for carrying out the multi-hop routing
of messages across the network. FFD can send message to the other FFDs and RFDs.
[17][15]
4.3.3 Reduced Function Device
Reduced Function Device (RFD) is not able to do same function as PAN coordinator and
coordinator does. It works as the end node of the network and cannot communicate with
other RFD rather they can only communicate with the FFD.RFDs polls the data for the
coordinator and then it gets the data from the coordinator and then send the data to other
Moveable Light Switch
- 23 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
nodes. After sending the data it goes back to sleep mode for saving energy. Normally it is
operated by battery powered.[1][17][16]
Fig 4.2 ZIGBEE DEVICES [15]
In order to use minimum power and to give longer battery life in battery-powered devices,
end devices has to spend most of their time in asleep mode , they wake up only when there is
need to communicate with other devices and after completing the communication they again
go back to sleep mode. But the routers and the coordinator both are connected to mains
powered and they do not go to sleep mode .[15]
4.4 The ZigBee Protocol
The ZigBee protocol is a product of the ZigBee Alliance which was formed in 2002. The
ZigBee Alliance focusing on the standardization of LR-WPAN technology for applications in
the industrial, building automation, and consumer markets. The upper layer (Network and
application) of the protocol stack is defined by the zigbee alliance while the lower (MAC and
physical) is defined by the IEEE 802.15.4 lower layers.[18]
Moveable Light Switch
- 24 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig.4.3 Architecture of Zigbee [15]
The zigbee stack is shown in the figure, both the PHY and MAC layer are specified in IEEE
802.15.4. The ZigBee alliance provides network (NWK) layer and the framework for
application layer standards, which includes the application support sub-layer (APS)，the
ZigBee device objects (ZDO) and the manufacturer-defined application objects.
4.5 Network layer
The network layer is built upon the IEEE 802.15.4 MAC’s features for following the
extensibility of coverage, the cluster can be added in the networks and networks can be
spitted.
The ZigBee NWK layer mainly provides these functions as:

it Establishes a new network

It is used for Joining and leaving a network.

When new device joins the network then it configures the stack.
Moveable Light Switch
- 25 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project

Address is assigned when device join the network, this operation is performed by the
coordinator.

it routes the message to the destinations

it Enables a device for synchronizing with another device either through tracking
beacons or by polling

it applies security operations[20]
4.6 Application layer:
The application layer is made up of APS sub-layer and ZDO. It includes Application which
are defined by manufacturer and these applications may be hardware or software.
APS sub-layer is used for providing discovery and binding services. Discovery is done for
detecting of devices which works in the range of a device. Binding is used for matching two
or more devices simultaneously and forward messages between bound devices.
Responsibilities of the ZDO are responsible for defining the role of devices in the network,
initiating and/or responding to binding requests and establishing a secure relationship
between network devices.[20]
4.6.1 Application Support Sub layer (APS)
The APS sub layer does the following operation:
• It is used for binding tables.
• It routes the message forwarding between bound devices.
• It is group address definition and management.
• It does mapping the address from 64-bit extended addresses to 16-bit NWK addresses.
• It does fragmentation and reassembly of packets.
• It is reliable data transport.[20][14]
4.6.2 Application Framework
The application framework is an environment where application objects are sent and received
the data. These objects are defined by the manufacturer of the ZigBee-enabled device and
these objects lie at the top of the application layer .Basically these application object
implements the application and these application can be a light bulb, a light switch, an LED,
an I/O line, etc. [20][15]
Moveable Light Switch
- 26 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
4.6.3 ZigBee Device Object (ZDO)
The ZDO is used for managing the overall device and it does the following operation:

It initializes the APS sub layer and the NWK layer

It defines the operating mode of the device (i.e., coordinator, router, or end device).

It does the device discovery and determines which application is being provided by
the device.

it initiates and respond to binding requests[20][16]
ZigBee Network Layer Function
Coordinator
Router
End Device
Establish a ZigBee network
YES
Permit other devices to join or leave the
network
Assign 16-bit network addresses
YES
YES
YES
YES
Discover and record paths for efficient YES
message
delivery
Discover and record list of one-hop YES
neighbours
YES
Route network packets
YES
YES
Receive or send network packets
YES
YES
NO
Join or leave the network
YES
YES
NO
Enter sleep mode
NO
NO
NO
YES
Table 4.1 Comparison of ZigBee Devices at the Network Layer[20]
Moveable Light Switch
- 27 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
4.7 ZigBee Implementation: Hardware and
Considerations
Firmware
There are three basic options for ZigBee hardware implementations are available:
4.7.1 Chipset reference designs
ZigBee chipmakers provide reference designs which, can be used for as many different
applications as possible, with chipset reference design the, time and expense of custom
design can be avoided with chipset reference design.[21]
4.7.2 Chipset custom designs
The space and recurring product expense is saved by using a custom design around a chipset.
4.7.3 Design-in modules
In the design module the OEM module manufacturer’s work with ZigBee-compliant chipsets,
which provide solution for applications.RF work is considered complete with module
solution. If the user gets a solution which meets the demands of application then development
cost can be reduced greatly.[21]
4.8 ZigBee Implementation: Profile Considerations
Both chipset and the stack are considered complete without a profile, profile is used to define
the module application. There are two types of profiles are available public profiles and
private profiles.
For ZigBee, Logo Certification is provided for public profiles. But private profiles are not
provided certification because they cannot use interoperate.
Till now only one ZigBee public profile is available which is used for light application If the
user are developing a ZigBee solution for any other type of application, and can’t get the
development of an appropriate public profile, user will need to go with one of the private
profiles that have been developed, or develop their own profile.
Some chipmakers are creating their private profiles which are integrated into zigbee stacks,
UARTs is a typical example of this. Now a day’s Module manufacturers are introducing
profiles which are used for specific application and it can full fill the user need.[21]
Moveable Light Switch
- 28 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
5. Selection of devices:
The main part of this project was Xbee module by the Maxstream manufacturer. Apart from
this there are other devices which have been used in this project and these are as follows.
5.1 XBee and XBee-PRO Product Comparison
Maxstream’s provides two different ZigBee-based RF module the XBee and the XBeePRO.
Both of these two modules can be differentiated in terms of range of communication and the
power consumption during transmission. But both of these modules consume same power
during reception. The XBeePRO costs £16.00, while the XBee costs only £11.00, it is clear
that these two modules give a choice for range of communication and power. Because we are
using a light application so that’s why we decided to go for xbee module and ordered xbee.
Both the XBee and XBee-PRO OEM RF Modules provide small, high-performance, lowcost, wireless data transceivers. Both of these modules operate in the 2.4 GHz ISM band. The
XBee and XBee-PRO both can be replaced with each other for interfacing board but the size
of XBee-PRO is slightly longer than the XBee. Both of these modules come with three
different antennas a whip antenna, a low-profile chip antenna or a U.FL connector. The
transmits power of XBee up to 1 mW but the XBee-PRO has more power than xbee up to 60
mW. Because xbee pro transmits more power that’s why it can receive weaker signal than
Xbee. In other words it gives better receiver sensitivity. Because of the feature of having
more transmitted power and more sensitive, it is capable for sending and receiving data for
longer distances than Xbee. The specification of both Xbee and Xbee Pro is shown in fig. 5.1.
Fig.5.1 Antenna options for XBee modules[25]
Moveable Light Switch
- 29 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Specifications
Performance
XBee
up to 100 ft. (30 m)
Indoor/Urban Range
Outdoor RF line-of- up to 300 ft. (100 m)
sight Range
Transmit Power Output 1 mW (0 dBm)
Power
Requirements
RF Data Rate
250,000 bps
Receiver Sensitivity
-92 dBm (1% PER)
-100 dBm (1% PER)
Supply Voltage
2.8 – 3.4 V
2.8 – 3.4 V
Transmit
(typical)
Current 45 mA (@ 3.3 V)
55 mA (@ 3.3 V)
< 10 μA
< 10 μA
Frequency
ISM 2.4 GHz
ISM 2.4 GHz
Dimensions
0.960” x 1.087”
(2.438cm x 2.761cm
-40
to
85º
C
(industrial)
0.960” x 1.297”
(2.438cm x 3.294cm)
-40
to
85º
C
(industrial)
FCC Part 15.247
U.FL
Connector,
Chip Antenna
or Integrated Whip
Antenna
Point-to-Point, Pointto-Multipoint,
Peer-to-Peer
and
Mesh
16 Direct Sequence
Channels
(software selectable)
PAN ID, Channel
& Source/Destination
Addresses
OUR-XBEE
U.FL
Connector,
Chip Antenna
or Integrated Whip
Antenna
Point-to-Point, Pointto-Multipoint,
Peer-to-Peer
and
Mesh
12 Direct Sequence
Channels
(software selectable)
PAN ID, Channel
& Source/Destination
Addresses
OUR-XBEEPRO
Industry Canada (IC)
4214A-XBEE
4214A-XBEEPRO
Europe (CE)
ETSI
ETSI
(Max
TX
output = 10 mW)
Antenna Options
Supported Network
Topologies
Number of Channels
Filtration Options
Agency
Approvals
215 mA (@ 3.3 V,
18 dBm)
Power-down Current
Operating Temperature
Networking
and Security
up to 1 mile (1.6 km)
60 mW (18 dBm)*,
100 mW EIRP*
250,000 bps
Idle / Receive Current 50 mA (@ 3.3 V)
(typical)
General
XBee-PRO
up to 300 ft. (100 m)
Table 5.1 Specification of Xbee and Xbee Pro
Moveable Light Switch
- 30 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
This antenna has been shown in figure. Both The whip and chip antennas are integrated onto
the modules, while the U. FL. RF connector is used for connecting an external antenna. Table
gives a comparison between the performances of this antenna. Same performance like whip
antenna from U. FL RF connector can be received when it is connected to dipole. The whip
antenna gives better slightly better performance than the chip antenna, and we decided to go
with the whip antenna. [25]24]
In terms of performance the dipole chip and whip give similar performance. And both of
these antennas having a similar radiation pattern. While the chip antenna radiation pattern is
not as uniform as that of the whip antenna, radiation pattern is affected by the surrounding.
5.2 Modules and modems:
Modules and modems are devices which are based on SoC or transceivers with MCU. They
are small integrated circuits. They come with pre‐flashed firmware and usually, the internal
components do not have direct access with custom firmware. There are so many
manufacturers for the modules and they are providing module for user application.
5.2. 1 Radiocraft:
The radio craft introduces RC2300/RC2301 Zigbee-ready modules for a very compact
solution for a wide range of wireless network applications. This kit can be used for
developing and test protocol applications as well as ZigBee-based applications.
The kit can be used for developing the customer application, or any Zigbee network
implementation supports the RC230x hardware platform and then user In this case the user
can re flash the modules with their own application, and the program/debug interface could
be used for debugging also.
With the RC2300DK Demonstration Kit following function can be done:
o The RF performance of the modules can be evaluated.
o The user can develop their own application interfacing the modules.
o Build a prototype for user application can be built.
The demonstration board kit contains 2 demonstration boards with 2 RS232 serial cables and
2 6v dc battery .[26]
5.2.2 Meshnetics:
Meshnetics manufacture provides two versions of their basic module – one with balanced
RF port only and one with dual chip antenna.
Moveable Light Switch
- 31 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
The meshnetics zigbit development kit contains template application for bootstrap application
and customization. It supports programming for OEM application through its CPAI.
It contains tools for range measurement, serial configuration interface and wireless sensor
networking demo application. The kit fully supports third party sensors which are selected by
sensor with source code for the hardware abstraction layer (HAL). The kit is convenient for
drivers and APIs for UART.[27]
5.2.3 Impulse:
Impulse manufacturer combines the maxstream’s xbee RF modem with the RCM3720 Rabbit
core module with an interface which help the customer for building a practical Sigsbee
wireless control network.
Combination of both zigbee and RCM3720 gives a low cost, wireless infrastructure which
gives the user to monitor and control remote devices. RCM 3720 rabbit core operates at 22.1
MHZ and 10 base-T Ethernet 512K flash,256 SRAM,1MB serial flash as on –board memory.
The kit contains three zigbee wireless modules and sample program, libraries which is used
for simple digital i/o feedback and control. The kit is an ideal for remote monitoring of
equipment, devices, wireless I/O control and simple data logging application.[28]
5.2.4 Microchip:
The microchip kit contains MRF 24J40 transceiver and Microchip PIC18 high performance
family. The demonstration kit contains the zigbee protocol stack and two PICDEM Z boards,
each with an RF daughter card. The PICDEm Z demonstrations kit contains zigbee software
stack which supports FFD, RFD and coordinator, PIC18LF4620 MCU which features nano
watt technology ,64KB flash memory and integrated peripherals.
5.2.5 2.4 GHZ 802.15.4 development kit:
The kit contains two development boards which includes Silicon Labs 8051-based MCU, an
802.15.4-compliant radio, JTAG connector for in circuit programming and debugging.[29]
5.2.6 Jennic:
Jennic comes with two module families The older of them uses JN5121 microcontroller and
now JN5139 is being used.
The JN5139 family comes with three different types of antennas – Ceramic, SMA and uFI.
Compared to other modules, which provides better sensitivity.
Jennic's evaluation kit gives a complete environment for the development of wireless sensor
network applications based on the JN5139 wireless microcontroller. The kit contains all the
hardware and software which is required for product development, with five network nodes,
an unrestricted software development kit.
Moveable Light Switch
- 32 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
The main application of the jennic is for Robust and secure low power wireless applications
,Wireless sensor networks, particularly IEEE802.15.4 / ZigBee systems ,Home and
commercial building automation, Home networks
5.2.7 RFM (Cirronet):
The Cirronet [37] modules are manufactured under the RFM brand. The two families of these
modules are available. Both of these families are providing 3 different versions which are
different in transmit power strength. High power versions can have on‐board antenna or not
.in terms of input voltage these modules are different from others because they operate at -5v
instead of 3v.
5.2.8 ZigBee and 802.15.4 (2.4 GHz):
Cirronet’s is a low power / low cost ZigBee radio solutions which fits well in to wireless
mesh networking for short-range, low-data applications which require long battery life and
low cost. Cirronet are suitable for home, commercial, and industrial applications which
operate from –40°C to +85°C.
5.2.9 Digi (MaxStream):
MaxStream [39] supplies two families of their XBee modules, both of them coming in
standard and boosted (XBee‐PRO) power versions. First generation, with Free scale’s
C13193 chip inside, is 802.15.4 compliant only, while the second features ZigBee Stack and
is certified for ZigBee and is based on Ember’s EM250. These are the only modules that
come in package with pins. Their parameters might not be exceptional, but still they are the
least expensive of all the modules mentioned in this thesis.[30]
MaxStream XBee ZNet 2.5 (Series 2):
For this project maxStream’sXBee ZNet 2.5 OEM RF Modules (Series 2) were chosen.
Initially, the jennic board and after that microchip zigbee Development kit were considered
for this light application , but finally the maxstream xbee starter kit was selected because of
its cost and availability.
If the performance of the maxstream starter kit is compared with other then maxstream is not
powerful than others but the price was lower. For making the project fast we ordered the
interface board that’s why we ordered the xbee starter kit, all these factors led us decide to go
with Maxstream kit.
5.3 Hardware versions
5.3.1 Antennas
Two variations of modules antennas are available – wire and chip. An external antenna can
be attached as well. There are two versions of modules with antenna connectors – with U.FL
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
connector (used e.g. in Wi‐Fi Mini PCI cards) and with reversed‐polarity SMA (common for
e.g. Wi‐Fi) connector.
5.3.2 PRO / Standard version
For applications where extended range is required, MaxStream offers a solution in the form
of power‐boosted modules. In absolute numbers, these modules offer 50mW (that means
+17dBm) extra power for North America and 10mW (+10dBm) power boost for nternational
use. The manufacturer claims that up to 1.6 km (1 mile) range can be reached
with PRO modules. The transmit current required by the PRO devices is, however, 295mA,
which results in about 1W of total power required for transmissions. Additionally, the PRO
modules are mm longer (24.3x32.9 mm (0.960x1.297 in) final size) than the standard version,
plus only
8
13 channels can be used. Standard versions have the ability to dynamically enable or disable
‘boost mode’ – mode of enhancing output power (by 2dBm) and receive sensitivity (by
1dBm) with a slight sacrifice of the battery life. Over more, there is another option of 4‐level
power regulation, enabling even more saving of battery life at end devices and higher gain at
routers.
5.4 Firmware versions
5.4.1Communication Interface:
There are two types of firmware are available based on their communication:

AT – it is called a transparent operation in this commands are entered in a special
mode

API –in this mode structuralized packets is used for communication but it is possible
to use both AT and API in a same network.
5.4.2 Device type / purpose:
Based on device, the firmware can be of three types:
 Router
 End device
 Coordinator
In order to create a coordinator, a ‘ZigBee (or ZNet 2.5) Coordinator’ firmware must be
flashed to the device by the X‐CTU software.
5.4.3 Firmware capabilities:
Based on capabilities, there are two firmware available Zigbee and Znet. Zigbee and ZNet 2.5
both of these two firmware’s are interchangeable and compatible for both radio and UART
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
communication. However, there are some minor issues and undocumented differences
between the firmware’s which have been shown in the table
Zigbee
Extended Node Discovery options
Enciphering
Periodic IO Sampling
Associate LED blink time speed
control
IN wake from cyclic sleep
No
No
No
No
ZNet 2.5
Yes
Yes
Yes
Yes
No
Yes
Table 5.2 Issues of Zigbee and Znet
5.4.4 Coordinator:
It is called also called a heart of the network. Channel and panid is provided to coordinator
to make the network but before to choose a channel all the available channel are scanned by
the coordinator by doing this it does not use already assigned PAN id.
The energy scan is called passive and the PAN ID discovery process is active. It means that
every device is listened and power level is measured during energy scanning. But in the
discovey, channel which is selected by the energy scan are sent a single hop broadcast
beacon request. After this beacon frame is sent by any nearby routers which contains
source PAN ID and then device either allows joining or not.
A passive PAN ID scan could be performed by listening for a beacon packet on the channel.
When scan is finished then coordinator tries to attempt to start on an unused PAN ID and
channel. After that both the PAN ID and channel parameters are saved and kept even after
reset.
By default the network address of coordinator is always 0x0000 and the user can define
which channel to use for scanning but they can’t define the cannel to operate.
5.4.4 Router
A router device can only join an already existing ZigBee network. In order to discover the
existing networks, active pan id is scanned by the routers. If the address of the ID parameter
is set to 0xFFFF, then the router will try to join any available network. Otherwise, the device
will seek to join a network which has PAN id address equal to the ID parameter.
When a router gets a response to the beacon request from a device that belongs the desired
network which allows joining, after this association request is sent back to this device. Then
An association response is sent back with 16 bit network address which indicates that router
has been allowed to the network.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
When router joins the network then it sends a broadcast discovery frame for finding out the
coordinator 64 bit address. Once it gets a coordinator address then it can do the routing of
data.
5.4.5 End device
The same thing the end devices does in order to join the network but neither it can allow any
device to join itself nor it can participate in routing.
Comparatively to API mode, the AT mode has less feature but in terms of communication it
is much simpler. Data is received at UART and packetized and sent to the radio.
The module which does communication with AT firmware cannot broadcast because they are
fixed to one destination.
AT firmware is used for applications where every device is always communicating only with
a single target. Like point to point links, such as remote controls for TV or Models, or any
other applications where XBees can act as a replacement of serial cable.
5.5 Mode of Operation:
When xbee module is not receiving or transmitting data, the RF module is in Idle Mode.
When RF module is in the Idle Mode, then RF module periodically checks for valid RF data.
The module goes in to other modes of operation when any of the following condition is met.
• Transmit Mode (Serial data in the serial receive buffer is ready for sending the data)
• Receive Mode (antenna receives the Valid RF data)
• Sleep Mode (End Devices only)
• Command Mode (Command Mode Sequence is issued)
5.5.1 Transmit Mode
RF module has to send the data when serial data is received and then RF module will exit Idle
Mode. The node which will receive the data is determined by the destination address. Before
to transmit the data, the module makes sure the 16-bit Network Address and after that data is
sent to the destination address. Address is not known, Network Address Discovery is used
when 16-bit address is not known. In case if the route is not known then route discovery
works for finding a route. At last packet is discarded if the network is not discovered because
the data is sent when the route is established.
5.5.2 Receive Mode:
The data is sent to the serial transmit buffer when valid RF packet is received and its address
matches the RF module’s 16- bit source address.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
5.5.3 Command Mode:
Module goes in to the command mode in order to modify or read RF Module parameters.
Basically a state in which all incoming serial characters are interpreted as commands is called
command mode.
AT Command Mode
To Enter AT Command Mode
In order to enter in to the command mode three order character sequence is sent “+++” and
guard time is observed before and after the command.
AT Command Syntax
5.5.4 Sleep Mode:
Only end devices can be in Sleep modes. Both Router and coordinator devices take part in
routing the data packets and connected with mains powered. Before to communicate over
ZigBee network, the end devices has to join a parent (router or coordinator) the parent device
does not force the end device to awake or asleep.
Instead, the end device has to inform the parent that it is able to receive data. The parent has
to keep all incoming data packets in buffer which are destined for the end device until the end
device can awake and receive the data. When an end device is ready to receive the data, then
a poll command is sent to the parent. When poll command is received by the parent router or
coordinator then it transmits any buffered data packets for the end device. Both the Routers
and coordinators are capable of buffering the packets for the end devices
5.6 XBee Series 2 OE M RF Modules
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
The XBee Series 2 OEM RF Modules has been designed to operate within the ZigBee
protocol and support the unique needs of low-cost, low-power wireless sensor networks. The
modules require minimal power and provide reliable delivery of data between remote
devices. The modules operate within the ISM 2.4 GHz frequency band.
Key Features:
Indoor/Urban: up to 133’ (40 m)
Outdoor line-of-sight: up to 400’ (120 m)
Transmit Power: 2 mW (+3 dBm)•
Receiver Sensitivity: -95 dBmRF
Data Rate: 250,000 bps
Advanced Networking & Security:
Retries and Acknowledgements
DSSS (Direct Sequence Spread Spectrum)
Each direct sequence channel has over 65,000 unique network addresses available
Point-to-point, point-to-multipoint and peer-to-peer topologies supportedSelf-routing,
self-healing and fault-tolerant mesh networking
Low Power:
XBee Series 2•
TX Current: 40 mA (@3.3 V)•
RX Current: 40 mA (@3.3 V)•
Power-down Current: < 1 μA @ 25oC
Easy-to-Use:
No configuration necessary for out-of box RF communications
AT and API Command Modes for configuring module parameters
Small form factor
Extensive command set
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Free X-CTU Software (Testing and configuration software)
5.7 PIC 16F88:
The PIC16F87/88 comes under the family of the PICmicro devices.PIC16F88 is a low
power8-bit RISC microcontroller.
PIC16F87/88 contains two memory block, program memory and data memory. The data
memory is broken down into the general purpose RAM and the Special Function Registers
(SFRs). The SFRs are used for controlling the peripheral modules. The data memory contains
the data EEPROM memory, which is indirectly mapped to the data memory. EEPROM
memory is used to read/write the data. The PIC16F87/88 contains 256 bytes of data
EEPROM memory from the range of 00h-FFh.
During the normal operation both data EEPROM and FLASH program memory are readable
and writable .this memory is indirectly mapped through the Special Function Registers.
A byte is written in data EEPROM memory which automatically erases the location and
writes the new data. The PIC16F87/88 can be operated in eight different oscillator modes.
1. LP Low-Power Crystal
2. XT Crystal/Resonator
3. HS High-Speed Crystal/Resonator
4. RC External Resistor/Capacitor with FOSC/4 output on RA6
5. RCIO External Resistor/Capacitor with I/O on RA6
6. INTIO1 Internal Oscillator with FOSC/4 output on RA6 and I/O on RA7
7. INTIO2 Internal Oscillator with I/O on RA6 and RA7
8. ECIO External Clock with I/O on RA6
Fig.5.2
Moveable Light Switch
Pin diagram of PIC16F88
- 39 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
PIC 16F88 has two I/O port PORTA and PORTB.PORTA is a bidirectional port(8
bit).TRISA is a data direction register.PORTA pin act as an input when TRISA bit is set to 1.
And act as output pin when TRISA is set to 0.
PORTB is also an 8-bit bidirectional port. It works as input and output same as PORTA
works by setting the TRIS register value.
It can operate with operating voltage levels from 2.0V to 5.0V. Table [5.1] summarizes
features available to the Atmega16.
Both C and assembly code can be executed by the program memory of microcontrollers. The
program memory is a Flash type. It has advantage over memory that it can rapidly erasable
and programmable. The I/ O ports are essential for microcontroller to control the function.
Any pin of the I/O port can be configured as an input or an output. The clock speed basically
decides how fast the code gets executed and microcontroller works by executing powerful
instruction in one clock cycle, the microcontroller gets the throughputs approaching 1 MIPS
per MHz and it means that, at least theoretically, at 16MHz the microcontroller is executing
16 MIPS.
5.8 Rs232
Information which is transferred between data processing equipment and peripherals are in
the form of digital data and then it is transmitted in either a serial or parallel mode. Parallel
communications are mostly used to connect the test instruments or computers and printers,
while serial is always used to connect computers and other peripherals.
In Serial transmission one bit of data is transmitted at a time over a single communications
line.
In contrast, parallel communications need the same line as the bits are being used to transmit
the data. Serial transmission is used for long distance communications while parallel is used
for short distances or when very high transmission rates are required.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig. 5.3 Pin description of RS-232[30]
RS-232 is used for “Interfacing between data terminal equipment and data communications
equipment using serial binary data exchange.” data terminal equipment (DTE) is used as the
computer, while data communications equipment (DCE) is used as the modem.
DB-9 Pin
RS-232
Name
Description
Implementation*
1
DCD
Data-Carrier-Detect
Connected to DSR (pin6)
2
RXD
Receive Data
3
TXD
Transmit Data
4
DTR
Data-Terminal-Ready
5
GND
Ground Signal
Serial data exiting the
module assembly (to host)
Serial data entering into the
module assembly (from
host)
Can enable Power-Down on
the module assembly
Ground
6
DSR
Data-Set-Ready
Connected to DCD (pin1)
7
RTS / CMD
Request-to-Send
Command Mode
/ Provides RTS flow control
or enables Command Mode
8
CTS
Clear-to-Send
Provides CTS flow control
9
RI
Ring Indicator
Optional power input that is
connected internally to the
positive lead of the front
power connector
Table 5.4 Pin Description of RS 232[30]
5.9 Usb
The USB is a medium speed serial data bus used for carrying large amount of data over short
cables and supports up to 12Mb/s the USB uses a seven –bit address and it supports up to127
different devices or nodes at a time but it can only have one host.
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
USB cable is made up of two twisted pair of wires ,one wire is used for carrying the
bidirectional serial data and other wire is used for 5V DC power which make its suitable for
low powered devices.
USB transfers the data in the form of packets and four different types of data format is used
by USB because it is used to handle different types of data.
Pin
1
Name
VBUS
Description
Power
2
D-
3
D+
4
GND
Transmitted
Received Data
Transmitted
Received Data
Ground Signal
Implementation
Power
the
RF
module
& Transmit data to and
from the RF module
& Transmit data to and
from the RF module
Ground
Table 5.5 Pin description of USB[30]
Value
0-20
Units
MHz
7168
bytes
368
bytes
256
bytes
Operating Frequency
FLASH Program Memory
Data Memory
EEPROM Data Memory
2
Serial Communication
1
ADC
4096
Instruction Set
10 bit A/ D module
3
Timers
USART
yes
I/O pins
16
CCP(PWM)
1
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Table 5.6 Feature of PIC16F88[31]
5.10 MPLAB Integrated Development Environment (IDE)
MPLAB Integrated Development Environment (IDE) software is used for comprehensive
editor, project manager and design desktop for application development of embedded designs
using Microchip PICmicro® microcontrollers.
The MPASM assembler (the assembler) is a Windows-based PC application which provides a
platform for developing assembly language code for Microchip's PICmicro microcontroller
(MCU) families.[32]
There are two executable versions of the assembler are available:

The windows version (mpasmwin.exe).is used with MPLAB IDE, in a stand-alone
Windows application, or on the command line.

The command-line version (mpasm.exe) is used this version on the command line,
Either from a command shell or directly on the command line.
MPLINK object linker (the linker) is used to combine the object modules which are
generated by the
MPASM assembler or the MPLAB C18 C compiler and convert into a single executable
(hex) file.
The files which are generated by the MPLIB object librarian are accepted by the linker as an
input. The process of linking is controlled by a linker script file.[32]
5.11 XBee/XBee-PRO Code Development
Three are different methods for software development are available for customers who want
to develop their own application with the XBee or XBee-PRO Module. Customer
applications should be written to interface to one of the following software interfaces:

Freescale-provided SMAC

Freescale 802.15.4 PHY and MAC

Figure 8 ZigBee stack
Using the MaxStream Bootloader
XBee and XBee-PRO Modules come with the MaxStream Boot loader. The Boot loader
sector is used for containing a unique 64-bit serial number and information for each module.
The stored information values help the XBee-PRO Modules to achieve 18 dBm power output.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
If the Multilink programmer tries to use the program the modules, stored values are lost and
then the XBee-PRO achieve only 12 dBm power output. [30]
The unique serial number and information can be stored by programming application code
using the X-CTU programming utility. In order to do this, the linker has to reserve a section
in flash from 0xFE00 – 0xFFFF for the Boot loader and redirect the Interrupt vector table.
In order to use the X-CTU software for programming the application code into the modules,
an MXI file is created. The MXI file should have the same name as the corresponding hex
file.
X-CTU software has been provided by MaxStream, Which is used to interface with and
configure MaxStream RF Modules. The software application is organized into the following
four tabs:
• PC Settings tab - Setup PC serial ports for interfacing with an RF module
• Range Test tab - Test the RF module's range and monitor packets sent and received
• Terminal tab - Set and read RF module parameters using AT Commands
• Modem Configuration tab - Set and read RF module parameters
Fig 5.4 for the setting the baud rate, for range test, configure the Modem
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig, 5.5for the setting the baud rate, for range test, configure the Modem
Fig, 5.6 for the setting the baud rate, for range test, configure the Modem
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig 5.7 for the setting the baud rate, for range test, configure the Modem
For using the X-CTU software, a module assembly (An RF module mounted to an interface
Board) should be connected to a serial port of a PC. And the interface data rate and parity
settings of the serial port ("PC Settings" tab) should match with the module (BD (Baud Rate)
and NB (Parity) .
A terminal program is built into the X-CTU Software and other terminal programs such as
"HyperTerminal" can be used with X-CTU when AT commands are used then the following
syntax is used :[30]
5.11.1Configuring the XBee from X-CTU Software
When module is powered up then all xbee devices are given an address of 0, by default. This
address can be changed through either the X-CTU software Modem Configuration tab or
using AT commands from a terminal window.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig. 5.8 configure the xbee from terminal
5.11.2 Configuring the XBee from Terminal
The next figure shows the in order to configure the xbee using a terminal window we have to
set baud rate at 9600.The device can be put in command mode by using a "+++". Guard time
is included before and after command for making sure data that contains this does not shift
the unit into command mode it means no other Data can be sent for a time period (guard
time) before or after the +++, this includes carriage returns.
Once it comes in to command mode, then AT commands can be used to configure the unit.
ATCN command is used to exit command mode.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig 5.8 configure the Xbee from command
6. Result
6.1 Experiment1:
The first experiment was designed to test the range of xbee module and RSSI was measured
to observe the RSSI of the packet.
In order to do the experiment of range test XCTU software & loop back adapter were used.
Tabs of “PC setting “ and “ range test” were used in X-CTU software.
First of all connection were set up and loopback adapter was connected with RS-232
development board. Loop back adapter is used for range testing and the loopback adapter
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
makes the module as a repeater by looping serial data in to the radio of transmission, during a
range test.
Fig6.1 for range test using loop back filter
After setting up the connection, PC COM port was selected that is used to connect the
module or interface with PC. In next step baud rate was matched with RF data rate. Range
test tab and RSSI was used to perform the range test and to observe the received signal
strength of the packet.
RSSI measurements were taken using the X-CTU software that came with xbee module. All
measurements were taken with line of sight. The two nodes were used for the test. one laptop
was used to communicate over the XCTU software and the second node was used as
feedback node for sending back the data to the laptop node. The measured were done by the
laptop node and result displayed by the X-CTU software.
43
6.1.1Result:
The test of the range of mode indicated that the ranges was confirmed to the specification
provided by the Xbee manufacturer. The range experiment was performed in indoor and we
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
got the range up to 32m ( indoor) and 30 m .range has been specified in the manual .it was
noticed that RSSI was good for up to 24 m but after that it started decreasing as we moved
far. In the end at 32 m we did not get any signal or range and RSSI was zero for the Packets.
6.2 Experiment 2:
Experiment 2 was performed to create a wireless link using PC and make it work as
moveable light switch. For performing this experiment both the USB and RS-232
development boards were connected to two different PC.
Fig. 6.2 Connection for Moveable light switch
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
Fig.6.3 Sending data by Xbee as light switch
Fig. 6.4 Receiving data by Xbee for Light input
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
USB development board was used as a switch and RS2322 was used as a light Code were
created for both USB and RS232 Development boards and code were run on each computer
in order to make the application work. Range has been specified by the Xbee manufacturer
6.3 Experiment 3:
Experiment 3bee module using PIC16F88. This experiment was to add more light switches at
the input and more light at the output
For this experiment PIC16F88 the microcontroller was interfaced with xbee module.
First only one microcontroller was used with USb development boards.
Fig. 6.5 Interfacing Microcontroller with Xbee
Result:
For this experiment we could not find the result, was used for creating a wireless link.
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
7. Conclusion:
The conclusive of this project is that it has been seen that zigbee is suitable for embedded
wireless development because of its fast and easy operation.
The master project has shown that developing an application of light switch with zigbee is
possible, which can be used in home, industry as well. It is confirmed that zigbee is more
likely to be used in building automation and industrial networks.
Zigbee has a lot of features which make it suitable for control applications. It is low cost, low
power and low data rate standard. It supports multi hop communication and mesh networking
by which grater range can be achieved
Zigbee has proved that it is most suitable for battery operated products. It does not provide
data rates in mega byte but it can be used efficiently in home and industrial application which
does not require high voltage.
Unexpected problems were faced while developing project and it was difficult to manage
time. The other major problems were found that one of the xbee modules had stopped
working.
From the feasibility report it was decided that to use zigbee chips for the light application but
after t considering the facts of cost, the xbee module was decided to use. Xbee module to do
work with xbee module was reliable for example range measurements, simplicity of using
AT firmwares)
To develop PIC microcontroller was difficult because of software MPLAB IDE. Wirless link
between zigbee modules has been successfully developed using PC.but it has ben seen that
when xbee is given the power from outside instead of USB board and program is stored in the
Xbee module and after that light switch was put from outside and it was observed that xbee
were working successfully.
Future Work
In this project xbee module were used to make a light application. In future other module can
be added with these two modules and signal can be sent from the coordinator to another
module .for having a simple application star topology can be used, in which one module can
control the two end devices.
For getting a better range mesh topology can be used, in which data is sent from one end
point to another utill it reaches to the destination
Moveable Light Switch
- 53 -
Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
References:
1. Distributed cognitive coexistence of 802.15.4 with 802.11 experience from Sofie Pollin
Mustafa, Ergen, Antoine Dejonghe, Interuniversity Micro-Electronics Center (IMEC),
University of Califiornia Berkeley.
2.
Microwave Tomography Using Dynamic 802.15.4 Wireless Networks, Mathew B.
Cover, Kiran Kanukurthy, Student Member, IEEE, David R. Andersen, Member, IEEE.
3.
IMPLEMENTATION OF IEEE 802.15.4 PROTOCOL STACK FOR
LINUX.(Thesis)
4 introductions to wirelss communication system
www.informit.com/content/images/0130422320/samplechapter/0130422320_ch01.pdf
5. Implementation of the zigbee network laye rand evaluation of route discovery initiation.
6. Comparison of the IEEE 802.11, 802.15.1, 802.15.4 and 802.15.6 wireless standards, Jan
Magne Tjensvold_September 18, 2007.
7. APPLICATIONS OF ZIGBEE WIRELESS TECHNOLOGY FOR INDUSTRIAL
INSTRUMENTATION ,T. D. Garnett, R. A. McMahon, and E. Abdi-Jalebi,University of
Cambridge, UK.
8. Overview of Wireless Sensors for Real-Time Health Monitoring of Civil Structures, J. P.
LYNCH
9. William C. Craig, Zigbee: "Wireless Control That Simply Works" , White paper, ZigBee
Alliance < www.zigbee.org >, Retrieval September 2005
10. ZigBee Alliance website, September 2002, “ZigBee Overview”
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Laboratory of Mechatronics and Instrumentation, 1113 Sofia
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Sameer Pai
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
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D. Manjunath, ECE Department, Indian Institute of Science, Bangalore, India, Ramakrishna
Boyina Honeywell Technology Solutions Pvt. Ltd., Bangalore, India
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Engineering and Computing, Unska 3, HR-10000 Zagreb, Croatia .
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33. Application Interface Boards for the ZigBee / IEEE 802.15.4 XBee® and XBee-PRO®
Wireless Network Transceivers
Moveable Light Switch
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Vikas Sharma
Department of Electronic, Communication and
Electrical Engineering
M.Sc. Project
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Moveable Light Switch
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Vikas Sharma