5/28/2016 to 5/8/2016
PTCL 6 Weeks
Summer
Internship Report
Submitted By:
Mr Aqeel Ahmed 14TL 62
Department of Telecommunication
Mehran University of Engineering
Jamshoro Sindh Pakistan
Wireless and Transmission Section
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PTCL 6 weeks summer internship Report 2016
PTCL 6 weeks summer internship Report 2016
Table of Contents
Preface .................................................................................................................................................... 5
Acknowledgement .................................................................................................................................. 6
PAKISTAN TELECOMUNICATION COMPANY LIMITED (PTCL) ............................................... 7
INTRODUCTION............................................................................................................................. 7
Corporate Vision ............................................................................................................................... 7
Mission ............................................................................................................................................... 7
Core Values........................................................................................................................................ 7
Business & Corporate Users ............................................................................................................ 8
Other business specific services include: ........................................................................................ 8
Landline ............................................................................................................................................. 8
EVO Wireless Broadband ................................................................................................................ 8
Broadband Pakistan ......................................................................................................................... 9
Smart TV (IPTV Service) ................................................................................................................. 9
V-fone ................................................................................................................................................. 9
International Network ...................................................................................................................... 9
Satellite Communication ................................................................................................................ 10
Wireless Section .................................................................................................................................. 11
Basic Terminology ................................................................................................................................ 11
Wireless signal Propagation ............................................................................................................... 18
Fading ................................................................................................................................................... 19
Antenna ................................................................................................................................................ 19
Isotropic radiator ................................................................................................................................... 19
Simple dipoles and Sectorized Antennas .............................................................................................. 20
Media Accesses..................................................................................................................................... 21
Frequency-Division Multiple Access (FDMA) ................................................................................. 21
Time-Division Multiple Access (TDMA)........................................................................................... 21
Code-Division MultipleAccess (CDMA) ........................................................................................... 21
General Architecture of CDMA ........................................................................................................ 22
Base Station SubSystem (BSS) .......................................................................................................... 23
Base Transceiver Systems (BTS) ....................................................................................................... 23
Base Station Controller: ..................................................................................................................... 25
Network switching subsystem (NSS) (or GSM core network) ........................................................ 25
Mobile switching Center MSC ........................................................................................................... 25
PTCL 6 weeks summer internship Report 2016
Home Location Register (HLR) ................................................................................. 26
Authentication Center AuC ............................................................................................................... 26
Visitor location register (VLR) ................................................................................................ 26
Billing center (BC) .............................................................................................................................. 26
Equipment identity register (EIR)..................................................................................................... 26
Transmission Section .......................................................................................................................... 27
Terminology......................................................................................................................................... 27

Guided media: ......................................................................................................................... 27

Unguided media ...................................................................................................................... 27

Bandwidth: .............................................................................................................................. 27

Transmission impairments ..................................................................................................... 27

Interference ............................................................................................................................. 27

Number of receivers:................................................................................................................ 27
GUIDED TRANSMISSION MEDIA ................................................................................................ 28
Twisted Pair..................................................................................................................................... 28
Coaxial Cable ...................................................................................................................................... 29
Optical Fiber........................................................................................................................................ 29
Different Modes of fiber Optical.................................................................................................... 30
Splicing of Optical Fiber ....................................................................................................................... 31
Fusion Splicing .................................................................................................................................. 31
Mechanical Splicing .......................................................................................................................... 31
SWOT ANALYSIS ......................................................................................................................... 32
Recommendations and Suggestions................................................................................................... 35
PTCL 6 weeks summer internship Report 2016
Preface
This report is all about the 6 week summer internship offered by Pakistan
Telecommunication Company Limited PTCL at Central Exchange Hyderabad
division. The report consist of the two sections mainly the Wireless Section and the
Transmission Section. The report first gives a brief introduction and programs of
PTCL and there are numerous technical concepts about the both section discussed
here. Main principle of wireless communication its architecture and working is also
discussed, principles of cellular communication and mobile networking are also part
of this report. After this different modes of transmission such as twisted pair, coaxial
cables and fiber optics are also included in this report. In the end this document
provides the SWOT analysis of based on the basis field work and observation.
PTCL 6 weeks summer internship Report 2016
Acknowledgement
First of all, I want to express all my humble thanks to ALLAH who is very sensitive
about each and every activity Of all his man and without whose help, I am unable to
accomplish any objective in my life. Secondly, I am great full to my worthy and
devoted supervisor Syed Mohammad Taqi for us encouragement, invaluable
guidance, advice and indispensable help without which the completion of this work
would not be possible. We are also very thankful to all the managers and staff
members of Transmission department for their co-operation in developing this
project.
I would also like to take this opportunity to express special thanks to our family for
their support and patients.
I am deeply indebted to a large group of teachers, friends and colleagues, who have
suggested, choose and advise us to be a member of Telecommunication technology.
PTCL 6 weeks summer internship Report 2016
PAKISTAN TELECOMUNICATION COMPANY LIMITED
(PTCL)
INTRODUCTION
PTCL is a largest telecommunications provide in Pakistan. PTCL also continues to be the largest
CDMA operator in the country with 0.8 million V-fone customers. The company maintains a leading
position in Pakistan as infrastructure provider to other telecom operators and corporate customers of
the country. It has the potential to be an instrumental agent in Pakistan’s economic growth .PTCL has
laid an optical Fiber Access Network in the major metropolitan centers of Pakistan and local loop
services have started to be modernized and upgraded from copper to an optical network. On the long
distance and international infrastructure side, the capacity of two SEA-ME-WE submarine cable is
being expanded to meet the increasing demand of international traffic
Corporate Vision
To be the leading Information and Communication Technology Service Provider in the
region by achieving customer satisfaction and maximizing shareholders' value'.
Mission
To achieve our mission by having: An organizational environment that fosters
professionalism, motivation and quality an environment that is cost effective and quality
conscious Services that are based on the most optimum technology "Quality" and "Time"
conscious customer service
Sustained growth in earnings and profitability
Core Values
 Professional Integrity
 Teamwork
 Customer Satisfaction
 Loyalty to the Company
PTCL is all set to redefine the established boundaries of the telecommunication market and is
shifting the productivity frontier to new heights. Today, for millions of people, we provide
instant access to new products and ideas. More importantly, by setting free the spirit of
innovation, we enable higher living standards through our ICT services.
PTCL is going to be your first choice in the future as well, just as it has been over the past six
decades.
PTCL 6 weeks summer internship Report 2016
Business & Corporate Users
For clear communication the first choice of business circles is PTCL landline telephone, for
local, nationwide and international calling. Today businesses can have 10-100 lines with
modern day services to meet their needs. These include options like Caller-ID, callforwarding, call-waiting, Call Barring, to name a few.
Other business specific services include:
0800-Toll free number, 0900-Preminum rate services, VPN-Virtual Private Network, Audio
Conference Service, Digital Cross Connect (DXX), ISDN (Policy), Tele plus (ISDN/BRI),
Digital Phone Facilities/ Modification Charges, UAN, UIN.
Landline
PTCL landline has always been a part of family and providing services from generations and
it continues to be the primary choice of customers for making voice calls for many decades.
PTCL gives its customers highest quality at very affordable rates along with attractive
packages and Value Added Services to choose from. PTCL offers many attractive packages
like Freedom Package, International Packages, Mobile Buckets & Double Up Unlimited
(double play services)
EVO Wireless Broadband
PTCL EVO Wireless Broadband is Pakistan’s fastest wireless internet which offers its
customers – “superior high-speed wireless internet experience”. EVO Wireless Broadband is
enabling the wireless broadband revolution in Pakistan like never before. PTCL EVO has
revolutionized the way people connect to the internet. PTCL EVO gives its customers the
advantage of seamless internet connectivity across Pakistan. EVO coverage is in over 350
cities, whereas EVO customers can also enjoy CDMA-1X data rates of up to 153.6 Kbps at
more than 1000 destinations across Pakistan.
PTCL Introduced EVO Nitro in Pakistan - “The World’s first & most cutting-edge EV-DO
Rev.B commercial network”. PTCL is the first operator in the world to commercially launch
EV-DO Rev.B products, which offer blazing fast speeds of up to 9.3 MBPS
PTCL 6 weeks summer internship Report 2016
Broadband Pakistan
The largest and the fastest growing Broadband service in Pakistan, PTCL Broadband is
making great positive changes in the lives of millions of people living in the country. Serving
over 1.3 million satisfied customers in over 2000 cities and towns across Pakistan, PTCL has
brought revolutionary efficiency and effectiveness in all segments of the society, be it the
rural or the urban. Since its launch on 19th May 2007, all PTCL Broadband packages are
designed for users to experience high-speed internet access with unmatched reliability,
affordability and connectivity all at the same time.
Smart TV (IPTV Service)
PTCL entered the media sector on 14th August 2008, by launching a digital interactive
television service for the first time in Pakistan. PTCL brought Pakistan in the list of a few
countries across the globe that offer this state of the art interactive TV service to its
subscribers. PTCL SMART TV service using its state of the art Broadband network employs
the IPTV (Internet Protocol TV) technology.
V-fone
PTCL also continues to be the largest CDMA operator in the country with approximately 1.4
million Vfone customers. It gives the liberty of payment in both prepaid and postpaid options.
It offers fixed wireless telephone for your homes & business. With CDMA2000 1X
technology, ours is the largest WLL network with a capacity of 2.6M, covering over 10,000
urban & rural areas. The network is already enabled for Voice, Dialup-Internet access
(153.6kbps), SMS and for EVDO Broadband.
International Network
PTCL’s ability to support both individual and corporate customers on a cross-border basis is
anchored by its extensive network of submarine cables.In order to ensure service availability
to expanded customer base of PTCL, the said bandwidth procurement was strategically
spread on each of our existing three submarine cable size. I-ME-WE, SEA-ME-WE3 and
SEA-ME-WE4. PTCL is the only telecom operator in Pakistan having a network of three
redundant and resilient submarine cable systems thus offering its customers better quality of
service.
PTCL 6 weeks summer internship Report 2016
Satellite Communication
PTCL has Intelsat Standard Earth Stations near Karachi and Islamabad. These installations
provide the diversity for International voice connectivity and also work as Hub for domestic
satellite users. There are four Intelsat Standard B Earth Stations at Islamabad, Gilgit, Skardu
and Gawadar.
PTCL 6 weeks summer internship Report 2016
Date : 28-06-2016 to 04-7-2016
Wireless Section
Definition:
Wireless is a term used to describe telecommunications in which electromagnetic
waves (rather than some form of wire) carry the signal over part or all of the
communication path. Some monitoring devices, such as intrusion alarms, employ
acoustic waves at frequencies above the range of human hearing; these are also
sometimes classified as wireless.
The first wireless transmitters went on the air in the early 20th century using
radiotelegraphy (Morse code). Later, as modulation made it possible to transmit
voices and music via wireless, the medium came to be called "radio." With the advent
of television, fax, data communication, and the effective use of a larger portion of the
spectrum, the term "wireless" has been resurrected.
Basic Terminology
Dow
Air Interface: The operating system of a wireless network. Technologies include
AMPS, TDMA, CDMA, GSM and iDEN.
AMPS: Advanced Mobile Phone Service (AMPS) is the original analog “cellular”
service transmission standard first deployed in the United States, still used as a default
standard for cellular systems in the U.S., and in some regions around the world.
Analog: The traditional method of adapting radio signals so they can carry
information. AM (Amplitude Modulation) and FM (Frequency Modulation) are the
two most common analog systems. Analog has largely been replaced by digital
technologies, which are more secure, more efficient and provide better quality.
Antenna: A device for transmitting and receiving radiofrequency (RF) signals. Often
camouflaged on existing buildings, trees, water towers or other tall structures, the size
and shape of antennas are generally determined by the frequency of the signal they
manage.
Base Station: The central radio transmitter/receiver that communicates with mobile
telephones within a given range (typically a cell site).
Bluetooth: The name for a technological standard (a communications protocol) that
enables mobile devices equipped with a special chip to send and receive information
PTCL 6 weeks summer internship Report 2016
wirelessly. Using Bluetooth, electronic devices such as desktop computers, wireless
phones, electronic organizers and printers can communicate over short-ranges using
the 2.4 GHz spectrum band.
Broadband: A transmission facility having a bandwidth (capacity) sufficient to carry
multiple voice, video or data channels simultaneously. Broadband is generally
equated with the delivery of increased speeds and advanced capabilities, including
access to the Internet and related services and facilities “that provide 200 kbps
upstream and downstream transmission speeds” (per the FCC’s Fourth Annual Report
to Congress.
CDMA (Code Division Multiple Access): A technology used to transmit wireless
calls by assigning them codes. Calls are spread out over the widest range of available
channels. Then codes allow many calls to travel on the same frequency and also guide
those calls to the correct receiving phone.
CDMA2000 1XRTT: The first step in the evolution to 3G is cdma2000 1X, which
improves packet data transmission capabilities and speeds in the network, and also
boosts voice capacity. (Speed of up to 307 kbps.)
CDMA2000 1XEV-DO: (Evolution Data-Only). CDMA2000 1XEV represents the
second step in the evolution of CDMA2000. Commercially launched in 2001, offers
data speeds of up to 2.4 Mbps.
CDMA2000 1XEV-DV: (Evolution Data-Voice). CDMA2000 1XEV represents the
next step in the evolution of CDMA2000. Approved by the International
Telecommunications Union (ITU), a standards body based in Geneva, as a 3G
technology to provide data and voice services together, with data rates of up to 3.09
Mbps.
Cell: The basic geographic unit of wireless coverage. Also, shorthand for generic
industry term "cellular." A region is divided into smaller "cells," each equipped with a
low-powered radio transmitter/receiver. The radio frequencies assigned to one cell
can be limited to the boundaries of that cell. As a wireless call moves from one cell to
another, a computer at the Mobile Telephone Switching Office (MTSO) monitors the
call and at the proper time, transfers the phone call to the new cell and new radio
frequency. The handoff is performed so quickly that it’s not noticeable to the callers.
Cell Site: The location where a wireless antenna and network communications
equipment is placed in order to provide wireless service in a geographic area
Channel / Circuit: A communications pathway that may take the form of a
connection established over wireless, wired, or fiber optic facilities.
CSD (Circuit Switched Data): One technological approach used for the exchange of
data. A circuit connection is made that is exclusively reserved for the individual’s use.
PTCL 6 weeks summer internship Report 2016
This can be inefficient, as many communications do not require a dedicated
communications channel, but only brief connectivity, for the transmission of short
messages.
CMRS (Commercial Mobile Radio Service) Provider: An FCC designation for any
wireless carrier or license owner whose wireless service is connected to the public
switched telephone network and/or is operated for profit. Wireless services that are
offered to the public are classified as CMRS, unlike private systems which are
classified as “Private Mobile Services.”
Co-Location: Placement of multiple antennas at a common site. Some companies
act as brokers or cell site managers, arranging cell sites and coordinating many
carriers' antennas at a single cell site.
Digital: Technological approach that converts signals (including voice) into the
binary digits ‘0’ and ‘1’. This data is compressed, and then transformed into
electronic pulses for a wired network, optical light waves for fiber optic networks or
radio waves for wireless networks. Digital wireless technology has largely
superceded analog technology, because digital delivers more capacity and supports
more applications, as well as offers better sound quality, and more secure signals.
DSL (Digital Subscriber Line): A digital line connecting the subscriber’s terminal
to the serving company’s central office, providing multiple communications channels
able to carry both voice and data communications simultaneously.
Dual Band: A wireless handset that works on more than one spectrum frequency,
e.g., in the 800 MHz frequency and 1900 MHz frequency bands. Dual Mode: A
wireless handset that works on both analog and digital networks.
EDGE: Enhanced Data Rate for Global Evolution is an evolutionary step in the
GSM-development path for faster delivery of data, delivered at rates up to 384 Kbps.
The standard is based on the GSM technology platform and uses the TDMA approach
(see TDMA, below).
ESMR (Enhanced Specialized Mobile Radio): A single wireless device that
combines a two-way radio, phone, mobile dispatch, radio paging and Mobile data
capabilities, and operates on digital networks. Examples of ESMR service providers
include Nextel Communications, Nextel Partners, and Southern LINC Wireless,
among others.
PTCL 6 weeks summer internship Report 2016
ESN (Electronic Serial Number): The unique serial identification number
programmed into a wireless phone by the manufacturer. Each time a call is placed, the
ESN is transmitted to a nearby base station so the wireless carrier can validate the call.
The ESN differs from the Mobile Identification Number, which identifies a
customer’s wireless phone number. MINs and ESNs are electronically monitored to
help prevent fraud.
FDD (Frequency Division Multiplexing): Frequency-division multiplexing is a
method in which numerous signals are combined for transmission on a single
communications channel. Each signal is assigned a different frequency (subchannel)
within the main channel.
GPRS (General Packet Radio Service): A packet technology approach that enables
high-speed wireless Internet and other GSM-based data communications. It makes
very efficient use of available radio spectrum for transmission of data.
GPS (Global Positioning System): A worldwide satellite navigational system, made
up of 24 satellites orbiting the earth and their receivers on the earth’s surface. The
GPS satellites continuously transmit digital radio signals, with information used in
location tracking, navigation and other location or mapping technologies.
GSM (Global System for Mobile Communications): A technological approach also
based on dividing wireless calls into time slots. GSM is most common in Europe,
Australia and much of Asia and Africa. Generally, GSM phones from the United
States are not compatible with international GSM networks because the U.S. and
many other nations use different frequencies for mobile communications. However,
some phones are equipped with a multi-band capability to operate on such other
frequencies
HSCSD (High Speed Circuit Switched Data): In using HSCSD a permanent
connection is established between the called and calling parties for the exchange of
data. As it is circuit switched, HSCSD is more suited to applications such as
videoconferencing and multimedia than 'bursty' type applications such as email, which
are more suited to packet switched data
Interconnection: Connecting one wireless network to another, such as linking a
wireless carrier's network with a local telephone company’s network.
Interoperability: The ability of a network to coordinate and communicate with other
networks, such as two systems based on different protocols or technologies.
LAN (Local Area Network): Local Area Network (LAN) is a small data network
covering a limited area, such as a building or group of buildings. Most LANs connect
workstations or personal computers. This allows many users to share devices, such as
laser printers, as well as data. The LAN also allows easy communication, by
facilitating e-mail or supporting chat sessions. Megahertz: Megahertz (MHz) is a unit
PTCL 6 weeks summer internship Report 2016
of frequency equal to one million hertz or cycles per second. Wireless mobile
communications within the United States generally occur in the 800 MHz, 900MHz
and 1900MHz spectrum frequency bands.
MIN (Mobile Identification Number): The MIN, more commonly known as a
wireless phone number, uniquely identifies a wireless device within a wireless
carrier's network. The MIN is dialed from other wireless or wireline networks to direct
a signal to a specific wireless device. The number differs from the electronic serial
number, which is the unit number assigned by a phone manufacturer. MINs and ESNs
can be electronically checked to help prevent fraud.
MVNO (Mobile Virtual Network Operator): A company that buys network
capacity from a network operator in order to offer its own branded mobile
subscriptions and value-added services to customers.
NAM (Number Assignment Module): The NAM is the electronic memory bank in
the wireless phone that stores its specific telephone number and electronic serial
number.
OFDM (Orthogonal Frequency Division Multiplexing): A system for the
transmission of digital message elements spread over multiple channels within a
frequency band, in order to achieve greater throughput while minimizing interference
and signal degradation through the use of multiple antennas.
Packet: A piece of data sent over a packet-switching network, such as the Internet. A
packet includes not just the data comprising the message but also address information
about its origination and destination.
Packet Data: Information that is reduced into digital pieces or ‘packets’, so it can
travel more efficiently across networks, including radio airwaves and wireless
networks.
PDA (Personal Digital Assistant): A portable computing device capable of
transmitting data. These devices offer services such as paging, data messaging, email,
computing, faxes, date books and other information management capabilities.
PIN (Personal Identification Number): An additional security feature for wireless
phones, much like a password. Programming a PIN into the Subscriber Information
Module (SIM) on a wireless phone requires the user to enter that access code each
time the phone is turned on.
POPs: For wireless, POPs generally refers to the number of people in a specific area
where wireless services are available (the population). For traditional ‘landline’
PTCL 6 weeks summer internship Report 2016
Communications, a “Point of Presence” defines the interconnection point between the
two networks.
Protocol: A standard set of definitions governing how communications are formatted
in order to permit their transmission across networks and between devices.
PSD (Packet Switched Data): A technological approach in which the communication
“pipe” is shared by several users, thus making it very efficient. The data is sent to a
specific address with a short delay. This delay depends on how many users are using
the pipe at any one time as well as the level of priority requested for your information.
PSD is the technology used for data communication across the Internet and makes
more efficient use of the network.
Repeater: Devices that receive a radio signal, amplify it and re-transmit it in a new
direction. Used in wireless networks to extend the range of base station signals and to
expand coverage. Repeaters are typically used in buildings, tunnels or difficult
terrain.
Roaming: When traveling outside their carrier's local service area, roaming allows
users to continue to make and receive calls when operating in another carrier’s service
coverage area.
Smart Antenna: A wireless antenna with technology that focuses its signal in a
specific direction. Wireless networks use smart antennas to reduce the number of
dropped calls, and to improve call quality and channel capacity.
Spectrum Allocation: Process whereby the federal government designates
frequencies for specific uses, such as personal communications services and public
safety. Allocation is typically accomplished through lengthy FCC proceedings, which
attempt to adapt allocations to accommodate changes in spectrum demand and usage.
Spread Spectrum: A method of transmitting a radio signal by spreading it over a
wide range of frequencies. This reduces interference and can increase the number of
simultaneous users on one radio frequency band.
TCP/IP (Transmission Control Protocol/Internet Protocol): A protocol permitting
communications over and between networks, the TCP/IP protocol is the basis for the
Internet communications.
TDMA (Time Division Multiple Access): A technological standard that permits the
transmission of information by dividing calls into time slots, each one lasting only a
fraction of a second. Each call is assigned a specific portion of time on a designated
channel. By dividing each call into timed ‘packets,’ a single channel can carry many
calls at once.
PTCL 6 weeks summer internship Report 2016
Third-Generation (3G): A general term that refers to technologies which offer
increased capacity and capabilities delivered over digital wireless networks.
UMTS (Universal Mobile Telecommunications Systems): This is third generation
technology generally based on W-CDMA (Wideband Code Division Multiple
Access). UMTS promises a communications speed between 384 kbps and up to about
2 Mbps.
VoIP (Voice over Internet Protocol): VoIP is not simply capable of delivering voice
over IP, but is also designed to accommodate two-way video conferencing and
application sharing as well. Based on IP technology, VoIP is used to transfer a wide
range of different type traffic.
Voice Recognition: The capability for wireless phones, computers and other devices
to be activated and controlled by voice commands.
WAN (Wide Area Network): A general term referring to a large network spanning a
country or around the world. The Internet is a WAN. A public mobile communication
system such as a cellular or PCS network is a WAN.
WAP (Wireless Application Protocol): Wireless Application Protocol is a set of
standards that enables wireless devices, such as phones, pagers and palm devices, to
browse content from specially-coded Web pages.
W-CDMA: Wideband Code Division Multiple Access, one of two 3G standards that
makes use of a wider spectrum than CDMA and therefore can transmit and receive
information faster and more efficiently.
WiFi (Wireless Fidelity): WiFi provides wireless connectivity over unlicensed
spectrum (using the IEEE 802.11a or 802.11b standards), generally in the 2.4 and 5
GHz radio bands. Wi-Fi offers local area connectivity to WiFi-enabled computers.
Wi-Max: A wireless technology based on the IEEE 802.16 standard providing
metropolitan area network connectivity for fixed wireless access at broadband speeds.
Wireless Internet: A general term for using wireless services to access the Internet,
e-mail and/or the World Wide Web.
Wireless Local Area Network (WLAN): Using radio frequency (RF) technology,
WLANs transmit and receive data wirelessly in a certain area. This allows users in a
small zone to transmit data and share resources, such as printers, without physically
connecting each computer with cords or wires.
PTCL 6 weeks summer internship Report 2016
From 4-7-2106 to 12-7-2016
Wireless signal Propagation
Radio propagation is also affected by several other factors determined by its path from
point to point. This path can be a direct line of sight path or an over-the-horizon path
aided by refraction in the ionosphere, which is a region between approximately 60 and
600 km above the earth's surface.
Receiving power additionally influenced by





fading (frequency dependent)
shadowing
reflection at large obstacles
scattering at small obstacles
diffraction at edges
Figure (1)
PTCL 6 weeks summer internship Report 2016
Fading
Fading is deviation of the attenuation affecting a signal over certain propagation
media. The fading may vary with time, geographical position or radio frequency, and
is often modeled as a random process. A fading channel is a communication channel
that experiences fading. In wireless systems, fading May either be due to multipath
propagation, referred to as multipath induced fading, or due to shadowing from
obstacles affecting the wave propagation, sometimes referred to as shadow fading.
Fading can have following effects on a signal




signal paths change
different delay variations of different signal parts(frequencies)
different phases of signal parts
quick changes in the power received (short-term fadingor fast fading)
Additional changes in
 distance to sender
 obstacles further away
 slow changes in the average power received (long-term fadingor slow fading)
Antenna
A device for transmitting and receiving radiofrequency (RF) signals. Often
camouflaged on existing buildings, trees, water towers or other tall structures, the size
and shape of antennas are generally determined by the frequency of the signal they
manage.
We have different types of antennas for different purposes:
Isotropic radiator
equal radiation in all directions (three dimensional) only a theoretical reference
antenna .Real antennas always have directive effects (vertically and/or horizontally)
Radiation pattern: measurement of radiation around an antenna
PTCL 6 weeks summer internship Report 2016
Simple dipoles and Sectorized Antennas
The dipoles are simple structure antennas with half wavelength, Sectorized antennas
are made from array of dipoles to direct the power in one particular direction. They
direct the energy in one direction.
PTCL 6 weeks summer internship Report 2016
From 12-7-2016 to 17-7-2106
Media Accesses
In telecommunications that resource is a transmission medium and is divided into
channels in order to allow multiple users to access the same transmission medium
simultaneously. This simultaneous use of channels is called multiple accesses. A
channel can be defined as an individually assigned, dedicated pathway through a
transmission medium for a single user's information. The physical medium of
transmission, which in our case is the wireless spectrum, can be divided into
individual channels based on a set of criteria. These criteria depend on the technology
that is utilized to make the distinction between channels.
Frequency-Division Multiple Access (FDMA)
In frequency-division multiple access (FDMA), the available bandwidth is divided
into frequency bands. Each station is allocated a band to send its data. In other words,
each band is reserved for a specific station, and it belongs to the station all the time.
Each station also uses a band pass filter to confine the transmitter frequencies. To
prevent station interferences, the allocated bands are separated from one another by
small guard bands.
Time-Division Multiple Access (TDMA)
In time-division multiple access (TDMA), the stations share the bandwidth of the
channel in time. Each station is allocated a time slot during which it can send data.
Each station transmits its data in is assigned time slot.
Code-Division MultipleAccess (CDMA)
Code-division multiple access (CDMA) was conceived several decades ago. Recent
advances in electronic technology have finally made its implementation possible.
CDMA differs from FDMA because only one channel occupies the entire bandwidth
of the link. It differs from TDMA because all stations can send data simultaneously;
there is no timesharing.
PTCL 6 weeks summer internship Report 2016
General Architecture of CDMA
PTCL 6 weeks summer internship Report 2016
Base Station SubSystem (BSS)
Base Station Subsystem is composed of two parts that communicate across the
standardized Abis interface allowing operation between components made by
different suppliers:
1. Base Transceiver Station (BTS)
2. Base Station Controller (BSC)
Base Transceiver Systems (BTS)
The base transceiver station, or BTS, contains the equipment for transmitting and
receiving radio signals (transceivers), antennas, and equipment for encrypting and
decrypting communications with the base station controller (BSC). Typically a BTS
for anything other than a pico cell will have several transceivers (TRXs) which allow
it to serve several different frequencies and different sectors of the cell (in the case of
sectorised base stations).
A BTS is controlled by a parent BSC via the "base station control function" (BCF).
The BCF is implemented as a discrete unit or even incorporated in a TRX in compact
base stations. The BCF provides an operations and maintenance (O&M) connection to
the network management system (NMS), and manages operational states of each
TRX, as well as software handling and alarm collection.
The functions of a BTS vary depending on the cellular technology used and the
cellular telephone provider. There are vendors in which the BTS is a plain transceiver
which receives information from the MS (mobile station) through the Um air
interface and then converts it to a TDM (PCM) based interface, the Abis interface, and
sends it towards the BSC. There are vendors which build their BTSs so the
information is preprocessed, target cell lists are generated and even intra cell handover
(HO) can be fully handled. The advantage in this case is less load on the expensive
Abis interface.
PTCL 6 weeks summer internship Report 2016
Logical Structure of a BTS
PTCL 6 weeks summer internship Report 2016
From 17-7-2106 to 22-07-2106
Base Station Controller:
The
base station controller (BSC) provides, classically, the intelligence behind the
BTSs. Typically a BSC has tens or even hundreds of BTSs under its control. The BSC
handles allocation of radio channels, receives measurements from the mobile phones,
and controls handovers from BTS to BTS (except in the case of an inter-BSC
handover in which case control is in part the responsibility of the anchor MSC). A key
function of the BSC is to act as a concentrator where many different low capacity
connections to BTSs (with relatively low utilization) become reduced to a smaller
number of connections towards the mobile switching center (MSC) (with a high level
of utilization). Overall, this means that networks are often structured to have many
BSCs distributed into regions near their BTSs which are then connected to large
centralized MSC sites.
Network switching subsystem (NSS) (or GSM core network)
It is the component of a GSM system that carries out call switching and mobility
management functions for mobile phones roaming on the network of base stations. It
is owned and deployed by mobile phone operators and allows mobile devices to
communicate with each other and telephonesin the wider public switched telephone
network (PSTN). The architecture contains specific features and functions which are
needed because the phones are not fixed in one location.
Mobile switching Center MSC
The mobile switching center (MSC) is the primary service delivery node for
GSM/CDMA, responsible for routing voice calls and SMS as well as other services
(such as conference calls, FAX and circuit switched data).
The MSC sets up and releases the end-to-end connection, handles mobility and handover requirements during the call and takes care of charging and real time pre-paid
account monitoring. In the GSM mobile phone system, in contrast with earlier
analogue services, fax and data information is sent directly digitally encoded to the
MSC. Only at the MSC is this re-coded into an “analogue" signal (although actually
this will almost certainly mean sound encoded digitally as PCM signal in a 64-kbit/s
timeslot, known as a DS0 in America).There are various different names for MSCs in
different contexts which reflects their complex role in the network, all of these terms
though could refer to the same MSC, but doing different things at different times.
PTCL 6 weeks summer internship Report 2016
Home Location Register (HLR)
The home location register (HLR) is a central database that contains details of each
mobile phone subscriber that is authorized to use the GSM core network. There can be
several logical, and physical, HLRs per public land mobile network (PLMN), though
one international mobile subscriber identity (IMSI)/MSISDN pair can be associated
with only one logical HLR (which can span several physical nodes) at a time.
Authentication Center AuC
The authentication center (AuC) is a function to authenticate each SIM card that
attempts to connect to the GSM core network (typically when the phone is powered
on). Once the authentication is successful, the HLR is allowed to manage the SIM and
services described above. An encryption key is also generated that is subsequently
used to encrypt all wireless communications (voice, SMS, etc.) between the mobile
phone and the GSM core network.
Visitor location register (VLR)
The Visitor Location Register (VLR) is a database of the subscribers who have
roamed into the jurisdiction of the MSC (Mobile Switching Center) which it serves.
Each main base station in the network is served by exactly one VLR (one BTS may be
served by many MSCs in case of MSC in pool), hence a subscriber cannot be present
in more than one VLR at a time.
Billing center (BC)
The billing center is responsible for processing the toll tickets generated by the VLRs
and HLRs and generating a bill for each subscriber. It is also responsible for
generating billing data of roaming subscriber.
Equipment identity register (EIR)
The equipment identity register is often integrated to the HLR. The EIR keeps a list
of mobile phones (identified by their IMEI) which are to be banned from the network
or monitored. This is designed to allow tracking of stolen mobile phones. In theory all
data about all stolen mobile phones should be distributed to all EIRs in the world
through a Central EIR. It is clear, however, that there are some countries where this is
not in operation.
PTCL 6 weeks summer internship Report 2016
From 22-07-2016 to 30-7-2016
TRANSMISSION SECTION
Definition: In telecommunications, transmission (abbreviation: Tx) is the process of
sending and propagating an analogue or digital information signal over a physical
point-to-point or point-to-multipoint transmission medium, either wired, optical fiber
or wireless.[1][2] One example of transmission is the sending of a signal with limited
duration, for example a block or packet of data, a phone call, or an email.
Transmission technologies and schemes typically refer to physical layer protocol
duties such as modulation, demodulation, line coding, equalization, error control, bit
synchronization and multiplexing, but the term may also involve higher-layer protocol
duties, for example, digitizing an analog message signal, and source coding
(compression).
Terminology
 Guided media:
Electromagnetic waves are guided along a solid medium, such as copper
twisted pair, copper coaxial cable, and optical fiber
 Unguided media
Wireless transmission occurs through the atmosphere, outer space, or water.
 Bandwidth:
All other factors remaining constant, the greater the bandwidth of a signal, the
higher the data rate that can be achieved.
 Transmission impairments
Impairments, such as attenuation, limit the distance. For guided media, twisted
pair generally suffers more impairment than coaxial cable, which in turn suffers
more than optical fiber.
 Interference
Interference from competing signals in overlapping frequency bands can distort
or wipe out a signal. Interference is of particular concern for unguided media,
but is also a problem with guided media. For guided media, interference can be
caused by emanations from nearby cables.
 Number of receivers:
A guided medium can be used to construct a point to-point link or a shared link
with multiple attachments. In the latter case, each attachment introduces some
attenuation and distortion on the line, limiting distance and/or data rate.
PTCL 6 weeks summer internship Report 2016
From 20-7-2106 to 25-7-2016
GUIDED TRANSMISSION MEDIA
Twisted Pair
The least expensive and most widely used guided transmission medium is twisted
pair.
Physical Description: A twisted pair consists of two insulated copper wires arranged
in a regular spiral pattern. A wire pair acts as a single communication link. Typically,
a number of these pairs are bundled together into a cable by wrapping them in a tough
protective sheath. Over longer distances, cables may contain hundreds of pairs. The
twisting tends to decrease the crosstalk interference between adjacent pairs in a cable.
Neighboring pairs in a bundle typically have somewhat different twist lengths to
reduce the crosstalk interference. On long-distance links, the twist length typically
varies from 5 to 15 cm.The wires in a pair have thicknesses of from 0.4 to 0.9 mm.
Unshielded and Shielded Twisted Pair
Twisted pair comes in two varieties: unshielded and shielded. Unshielded twisted pair
(UTP) is ordinary telephone wire. Office buildings, by universal practice, are prewired
with excess unshielded twisted pair, more than is needed for simple telephone support.
This is the least expensive of all the transmission media commonly used for local area
networks and is easy to work with and easy to install.
PTCL 6 weeks summer internship Report 2016
Coaxial Cable
Physical Description:
Coaxial cable, like twisted pair, consists of two conductors, but is constructed
differently to permit it to operate over a wider range of frequencies. It consists of a
hollow outer cylindrical conductor that surrounds a single inner wire conductor
(Figure 4.2b).The inner conductor is held in place by either regularly spaced insulating
rings or a solid dielectric material. The outer conductor is covered with a jacket or
shield. A single coaxial cable has a diameter of from 1 to 2.5 cm. Coaxial cable can be
used over longer distances and support more stations on a shared line than twisted
pair. Applications Coaxial cable is a versatile transmission medium, used in a wide
variety of applications.
The most important of these are
• Television distribution
• Long-distance telephone transmission
• Short-run computer system links
• Local area networks
Optical Fiber
Physical Description
An optical fiber is a thin (2 to ),flexible medium capable of guiding an optical ray.
Various glasses and plastics can be used to make optical fibers. The lowest losses
have been obtained using fibers of ultrapure fused silica. Ultrapure fiber is difficult to
manufacture; higher-loss multicomponent glass fibers are more economical and still
provide good performance. Plastic fiber is even less costly and can be used for shorthaul links, for which moderately high losses are acceptable. An optical fiber cable has
a cylindrical shape and consists of three concentric sections: the core, the cladding,
and the jacket (Figure 4.2c).The core is the innermost section and consists of one or
more very thin strands, or fibers, made of glass or plastic; the core has a diameter in
the range of 8 to Each fiber is surrounded by its own cladding, a glass or plastic
coating that has optical properties different from those of the core and a diameter of
The interface between the core and cladding acts as a reflector to confine light that
would otherwise escape the core. The outermost layer, surrounding one or a bundle of
cladded fibers, is the jacket. The jacket is composed of plastic and other material
PTCL 6 weeks summer internship Report 2016
layered to protect against moisture, abrasion, crushing, and other
environmental dangers.
• Greater capacity: The potential bandwidth, and hence data rate, of optical fiber is
immense; data rates of hundreds of Gbps over tens of kilometers have been
demonstrated. Compare this to the practical maximum of hundreds of Mbps over
about 1 km for coaxial cable and just a few Mbps over 1 km or up to 100 Mbps to 10
Gbps over a few tens of meters for twisted pair.
• Smaller size and lighter weight: Optical fibers are considerably thinner than
coaxial cable or bundled twisted-pair cable—at least an order of magnitude thinner for
comparable information transmission capacity. For cramped conduits in buildings and
underground along public rights-of-way, the advantage of small size is considerable.
The corresponding reduction in weight reduces structural support requirements.
• Lower attenuation: Attenuation is significantly lower for optical fiber than for
coaxial cable or twisted pair (Figure 4.3c) and is constant over a wide range.
• Electromagnetic isolation: Optical fiber systems are not affected by external
electromagnetic fields. Thus the system is not vulnerable to interference, impulse
noise, or crosstalk. By the same token, fibers do not radiate energy, so there is little
interference with other equipment and there is a high degree of security from
eavesdropping. In addition, fiber is inherently difficult to tap.
• Greater repeater spacing: Fewer repeaters mean lower cost and fewer sources of
error. The performance of optical fiber systems from this point of view has been
steadily improving. Repeater spacing in the tens of kilometers for optical fiber is
common, and repeater spacing’s of hundreds of kilometers have been demonstrated.
Coaxial and twisted-pair systems generally have repeaters every few kilometers.
Different Modes of fiber Optical
PTCL 6 weeks summer internship Report 2016
From 30-07-2016 to 5-8-2016
Splicing of Optical Fiber
Knowledge of fiber optic splicing methods is vital to any company or fiber optic
technician involved in Telecommunications or LAN and networking projects.
There are two methods of fiber splicing
Fusion Splicing
Preparing the fiber - Strip the protective coatings, jackets, tubes, strength members,
etc. leaving only the bare fiber showing. The main concern here is cleanliness.
Step 2: Cleave the fiber - Using a good fiber cleaver here is essential to a successful
fusion splice. The cleaved end must be mirror-smooth and perpendicular to the fiber
axis to obtain a proper splice.
Mechanical Splicing
Mechanical splicing is an optical junction where the fibers are precisely aligned and
held in place by a self-contained assembly, not a permanent bond. This method aligns
the two fiber ends to a common centerline, aligning their cores so the light can pass
from one fiber to another.
Step 1: Preparing the fiber - Strip the protective coatings, jackets, tubes, strength
members, etc. leaving only the bare fiber showing. The main concern here is
cleanliness.
Step 2: Cleave the fiber - The process is identical to the cleaving for fusion splicing
but the cleave precision is not as critical.
Distribution Frame
In telecommunications, a distribution frame is a passive device which terminates
cables, allowing arbitrary interconnections to be made. For example, the Main
Distribution Frame (MDF) located at a telephone central office terminates the cables
leading to subscribers on the one hand, and cables leading to active equipment (such
as DSLAMs and telephone switches).
PTCL 6 weeks summer internship Report 2016
Digital Distribution Frame
A Digital Distribution Frame (DDF) is the interface when coaxial cable has to be
terminated, organized or cross-connected in long-distant transport networks, or in
access networks close to subscribers.
Optical Fiber Distribution Frame
In optical distribution frame (ODF) is a frame used to provide cable interconnections
between communication facilities, which can integrate fiber splicing, fiber
termination, fiber optic adapters & connectors and cable connections together in a
single unit.
SDH and Sonet
Synchronous digital hierarchy (SDH) and synchronous optical network (SONET)
refer to a group of fiber-optic transmission rates that can transport digital signals with
different capacities. Synchronous Optical Networking (SONET) and Synchronous
Digital Hierarchy (SDH) are standardized protocols that transfer multiple digital bit
streams synchronously over optical fiber using lasers or highly coherent light from
light-emitting diodes (LEDs). At low transmission rates data can also be transferred
via an electrical interface.
SWOT ANALYSIS
PTCL is a big organization regarding all the departments including Finance, Operations,
Human resource etc. there are several strengths, weakness opportunities and thrats of
these departments, which will be discussed as follow:
PTCL 6 weeks summer internship Report 2016
Strengths
The Biggest Foreign Exchange Earner
PTCL is the biggest source of foreign exchange for Pakistan. It earns a lot foreign
exchange form its international traffic.
Adequate Financial Resources
PTCL earns billions of Rupees as a major source of capital. These adequate financial
resources not only enable the company to copy with any unexpected event but to deploy
its resources to increase product line and services without feeling any financial difficult.
Free From Competitive Pressure
PTCL has no competitor in the market and other companies are legally not allowed
enter in competition with PTCL before 2003.So PTCL is performing its activities freely
without any pressure.
Leadership In The Market
PTCL is leading Company to provide telecom facilities in the Pakistan. PTCL aims at
using the latest technology in the field of engineering and IT for its services. It is also
getting constancy from international Companies in order to remain leader in telecom
sector.
Modern Technology
PTCL is running modern technology to develop its products and services and improve
the quality of services. In this connection it has replaced the old exchanges with new
digital exchanges. It has computerized billing system. Due to this technology thousand
of complaints have been reduced. PTCL has also entered in the business of Mobile
phone and Internet services.
Human Resource Development
Human resource development and employment of technology towards modern
development.
Weaknesses
Ambiguity In Strategic Direction
PTCL is doing business very well but only to that extend to which customers respond.
Although PTCL is generating revenue from its value added services but it doesn’t have
any solid financial strategic outline, which can cope the entire complex financial
situation, and also ambiguity exists in implementation strategic financial plans.
Externally, PTCL has no competitors so it has no benchmark to gauge financial
performance of its different departments with those of competitors.
Seniority Bases Promotions
PTCL is leading information technology but it is not knowledge oriented so far as
promotions of its employees are concerned. Promotions of PTCL employees are
seniority based. Most of employees are concerned. Promotions of PTCL employees,
PTCL 6 weeks summer internship Report 2016
who get promoted on seniority basis, are less knowledgeable and nonprofessional and cannot cope with the challenges of this ever-growing
field. On the other hand most of its knowledgeable and well-educated employees have
no chance of getting higher Positions. They have to work under their boss who has more
experience but less knowledge about Information Technology and Telecommunication.
Lack of Human Resources Management
PTCL has no human resources management department. It doesn’t have clear policy
regarding hiring & training of work force. In PTCL, for most of the jobs there is no job
work & evaluation of performance of employees.
Customer Dissatisfaction And Delayed Responses
Many customer of PTCL are not satisfied with its services because of wrong billing,
late delivery of bills and delayed responses for any fault in the telephone. Some
customer complains that they received their bills in full amount although they have
stayed out of the home and had not use the telephone at all.
Opportunities
Increasing Awareness Rate
PTCL can show its interest in educating people & increasing literality rate. In this way,
PTCL will not only fulfill its social responsibility but will also be able to increase
awareness rate & it will be help full in the expansion of PTCL business.
Skillful human resources:
PTCL can improve the skill of its manpower by providing them the opportunities of
advanced courses that will make them to cope with the ever-changing condition in field
of telecommunication.
Entering The New Market
PTCL recently is starting its mobile services hence; it will enter in the market. PTCL
can expand its business by exploring and entering in new markets in similar way.
Telecom Facilities In Rural Areas
All the value added services and digital facilities are available only in the main cities of
Pakistan. PTCL can expand its business by providing telecom facilities in rural areas,
which is only possible when adequate planning is done.
Recruitment
PTCL can also improve the human resources by the selection of competent person for
different departments and this can only possible by discouraging the corruption and
favoritism.
Threats
Exchange Rate Risk
Exchange Rate Risk will cause PTCL net exchange loss on foreign loans. Devaluation
of rupees will increase the cost of production, machinery, and almost all the equipment,
PTCL 6 weeks summer internship Report 2016
imported from foreign countries. So exchange rate risk will affect the
Profitability of PTCL and also increase the risk of getting foreign loans in
future.
Government Legislation
Government policies can affect the performance of PTCL. Hence government policies
will be a real threat for PTCL if they are not in favor of PTCL business activities. This
can affect the recruiting policies of PTCL.
Turnover
At the end of the monopoly, competitors will enter the industry and the completion will
increase as a result of which they will offer high pays and facilities to skill-person of
the industry. This can increase the turnover of PTCL, which can create a serious threat
for the organization.
Decrease In Market Share Due To Competition
After the end of monopoly, dissatisfied customers may shift to those telecom services
providers who they think would offer better services than PTCL, and will increase
customer satisfaction. Decrease in market share would decrease the profitability of
PTCL, which will be a real threat in near future.Swot matrix table are on the other page.
Recommendations and Suggestions
 The equipment should be updated, the company is using the same BTS system since three
decades. Their efficiency has been reduced and traffic has increased, hence the system must
be time and technology oriented.
 Recruitment of technical people on the basis of merit should be done.
 Refreshing courses of the training are not scheduled and is not provided to all the staff
equally. I have a suggestion for it that training department should arrange the training
courses properly and it should be at least once a year.
PTCL 6 weeks summer internship Report 2016
 Top and lower level management both should attend the workshops,
seminars and meetings so that they can also give their suggestion and
opinion
 The backup should be stand by, because we have seen so many breakdowns during the rainy
seasons.
 The company is earning, so it should now go toward fiber to home concept.
 There must be trainings for technical staff from well know technical institution of the
country. And international trainings should also be arranged.
 PTCL is one of the leading provider of the internship in the telecommunication field. I would
recommend to increase this ratio more and more on the basis of merit so that larger number
of fresh engineers should avail such opportunities.
PTCL 6 weeks summer internship Report 2016