September 2004
doc.: IEEE 802.15-04-0472-01-004a
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Direct Sequence UWB Impulse Radio System ]
Date Submitted: [September 13th, 2004]
Source: [(1)Akira Maeki, Masaru Kokubo, Masayuki Miyazaki, Kenichi Mizugaki, Ryosuke Fujiwara,
(2)Yasuyuki Okuma, Miki Hayakawa, Shinsuke Kobayashi, Noboru Koshizuka, Ken Sakamura ]
Company [(1) Hitachi, Ltd., Central Research Laboratory and Advanced Research Laboratory,
(2) YRP Ubiquitous Networking Laboratory ]
Address [(1) 1-280 Higashi Koigakubo Kokubunji-shi, Tokyo 185-8601 JAPAN
(2)28th KOWA Bldg., 2-20-1, Nishi-Gotanda Shinagawa-ku, Tokyo 141-0031 JAPAN]
Voice:[+81 42.323.1111], FAX: [+81 42.327.7849], E-Mail:[a-maeki@crl.hitachi.co.jp]
Re: [Response to Call for Proposals]
Abstract: [This document proposes Hitachi, Ltd.’s PHY proposal for the IEEE 802.15.4 alternate PHY
standard]
Purpose: [Preliminary Proposal for the IEEE802.15.4a standard.]
Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for
discussion and is not binding on the contributing individual(s) or organization(s). The material in this
document is subject to change in form and content after further study. The contributor(s) reserve(s) the right
to add, amend or withdraw material contained herein.
Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE
and may be made publicly available by P802.15.
Submission
Slide 1
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Hitachi, Ltd.
Preliminary Proposal for
IEEE 802.15.4a Alternate PHY
DS- UWB Impulse Radio
Akira Maeki
Hitachi, Ltd.
Submission
Slide 2
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Contents
• DS-UWB IR Proposal
• Location Awareness
• Summary
Submission
Slide 3
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Direct Sequence UWB Impulse Radio
System (DS-UWB IR)
Impulse Radio
Transmitter
DBPSK
t
Pulse
Generator
PA
PRF=Tens of MHz
PRF :Pulse Repetition Frequency
Receiver
RF
Submission
Slide 4
BB
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
UWB Pulse and Spectrum
Initial Target
: Arbitrary Pulse
in Low Band (3.1-5.1GHz)
EIRP (dBm/MHz)
-40
-50
-60
-70
Low Band
(3.1-5.1GHz)
-80
High Band
(6-10GHz)
-90
0
1
2
3
4
5
6
7
8
9
10
11
Example:
• 2.5ns Gaussian Pulse
• Center Frequency=4.1GHz
• 3dB BW=660MHz
• TxPower (ave.)= - 9.8dBm
Frequency (GHz)
Submission
Slide 5
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Why DS-UWB IR?
• Low Power Consumption :
-Very Simple Architecture
-Low Rate Sampling ADC : Tens of Msps, 2-4bits
• Low Cost
-CMOS Implementation is Feasible (Peak Power <10dBm)
-Low Band (3.1-5.1GHz)
• High Location Accuracy : ~30cm in 30m range (AWGN)
Best Fit to 4a Applications (Sensor Network etc.)
Low Cost, Low Power, High Location Accuracy!
Submission
Slide 6
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Scalability
with spread factor
Data Rate
Modulation
Spread Factor
Number of
Pulses / Bit
32.0 Mbps
DBPSK
1
1
10.7 Mbps
DBPSK
3
3
4.57 Mbps
DBPSK
7
7
2.13 Mbps
DBPSK
15
15
1.03 Mbps
DBPSK
31
31
258 kbps
DBPSK
124
124
129 kbps
DBPSK
248
248
PRF=32MHz
Submission
Slide 7
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Link Budget
Value
0.129Mbps 30m
Value
1.03Mbps 10m
4096
4096
MHz
-9.8
-9.8
dBm
32
32
MHz
248
31
0.129
1.03
Mbps
44.7
44.7
dB
Distance
30
10
m
Decay coefficient
2.0
2.0
-
29.5
20.0
dB
3.0
3.0
dB
Antenna gain
-3.0
-3.0
dBi
Required Eb/N0 @PER=1%, 32B
14.0
9.8
dB
Noise Power Density
-174
-174
7.0
7.0
dB
11.9
16.5
dB
Parameters
Center Frequency
Transmit Power
(2.5ns Gaussian Pulse)
PRF
Spread Factor
Data Rate
Path Loss at 1m
Additional Path Loss at 30m,10m
Implementation Loss
Receiver Total NF
Margin
Submission
Slide 8
Units
dBm
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Implementation Feasibility
Example:
Transmitter
BPF
PA
Pulse
Generator
ANT.
Switch
Data
Spreading
Digital PHY
Analog RF
MAC
I
LPF
ADC
Digital Block
LNA
0/90
•Matched Filter
•Signal Acquisition
•Tracking
PLL
4.1GHz
Receiver
Data
etc.
LPF
Q
ADC
<150kgate
• Ranging
Submission
Slide 9
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Location Awareness
• Trilateration for Location Awareness
- 3 Known-location Nodes
- TDOA (Time Difference Of Arrival)
• High Location Accuracy : ~30cm in 30m range (AWGN)
Wireless/Wired Network
Monitor Terminal
TDOA
(t2-T2)
Reference Node 2
t2
T2
TDOA
(t1-T1)
Server & Data Base
T3
Reference Node 3
t3
“Calculation of the Node Location
based on the TDOAs and the Reference Locations”
For Sync.
T1
Time of Arrival: t1
Reference Node 1
Submission
TDOA
(t3-T3)
Node
System Configuration for 2D location measurements
(Synchronization by a node)
Slide 10
Akira Maeki, Hitachi, Ltd.
September 2004
doc.: IEEE 802.15-04-0472-01-004a
Summary
DS-UWB IR is very Simple and Best Fit!
-Low Power
-Low Cost :CMOS implementation
-High Location Accuracy
: ~30cm in 30m range at AWGN channel
Proposed DS-UWB IR
-fc=4.1GHz, BW=660MHz at Low Band (3.1-5.1GHz)
-2.5ns Gaussian Pulse with PRF of 32MHz
-DBPSK Modulation
Submission
Slide 11
Akira Maeki, Hitachi, Ltd.