ANALYZING THE SIGNAL FLOW AND RF PLANNING IN · PDF file... BCCH (Broadcast channel), MAL...
Transcript of ANALYZING THE SIGNAL FLOW AND RF PLANNING IN · PDF file... BCCH (Broadcast channel), MAL...
i
ANALYZING THE SIGNAL FLOW AND
RF PLANNING IN GSM NETWORK
A PROJECT REPORT
Submitted by
GOKULAPRIYA P
Register No: 14MAE005
in partial fulfillment for the requirement of award of the degree
of
MASTER OF ENGINEERING
in
APPLIED ELECTRONICS
Department of Electronics and Communication Engineering
KUMARAGURU COLLEGEOF TECHNOLOGY
(An autonomous institution affiliated to Anna University, Chennai)
COIMBATORE-641 049
ANNA UNIVERSITY: CHENNAI 600 025
APRIL 2016
ii
BONAFIDE CERTIFICATE
Certified that this project report titled “ANALYZING THE SIGNAL FLOW AND RF
PLANNING IN GSM NETWORK” is the bonafide work of GOKULAPRIYA.P
[Reg. No. 14MAE005] who carried out the work under my supervision. Certified further
that to the best of my knowledge the work reported herein does not form part of any other
project or dissertation on the basis of which a degree or award was conferred on an earlier
occasion on this or any other candidate.
HHHH
The candidate with Register No.14MAE005 was examined by us in the project
viva-voice examination held on...............................
INTERNAL EXAMINER EXTERNAL EXAMINER
SIGNATURE
R.KARTHIKEYAN
ASSISTANT PROFESSOR II
PROJECT SUPERVISOR
Department of ECE
Kumaraguru College of Technology
Coimbatore-641 049
SIGNATURE
Dr. A.VASUKI
HEAD OF THE DEPARTMENT
Department of ECE
Kumaraguru College of Technology
Coimbatore-641 049
iii
ACKNOWLEDGEMENT
First, I would like to express my praise and gratitude to the Lord, who has
showered his grace and blessings enabling me to complete this project in an excellent
manner.
I express my sincere thanks to the management of Kumaraguru College of
Technology and Joint Correspondent Shri Shankar Vanavarayar for his kind support
and for providing necessary facilities to carry out the work.
I would like to express my sincere thanks to our beloved Principal
Dr.R.S.Kumar Ph.D., Kumaraguru College of Technology, who encouraged me with
his valuable thoughts.
I would like to thank Dr.A.Vasuki Ph.D., Head of the Department, Electronics
and Communication Engineering, for her kind support and for providing necessary
facilities to carry out the project work.
In particular, I wish to thank with everlasting gratitude to the project
coordinator Ms.S.Umamaheswari M.E.,(Ph.D) Associate Professor, Department of
Electronics and Communication Engineering, throughout the course of this project
work.
I am greatly privileged to express my heartfelt thanks to my project guide
Mr.R.Karthikeyan M.E., Assistant Professor-II, Department of Electronics and
Communication Engineering, for his expert counselling and guidance to make this
project to a great deal of success and I wish to convey my deep sense of gratitude to all
teaching and non-teaching staff of ECE department for their help and cooperation.
Finally, I thank my parents and my family members for giving me the moral
support and abundant blessings in all of my activities and my dear friends who helped
me to endure my difficult times with their unfailing support and warm wishes.
iv
ABSTRACT
In this fast moving electronic world, planning, building and optimisation
process of radio access network is a complex dynamical activity, which requires a lot
of planning effort and time. This project is proposed in the intention of planning a
network with reduced call drops, which seems to be a very big issue among the
subscribers as well as the service providers. It is found that call drops in conventional
networks is less than 0.01% and in mobile network it is greater than 0.1%. As per
TRAI (Telecom Regularity Authority of India), call drops have doubled in last one
year. Call drops jumped two-fold on 2G and 65% on 3G networks. Since continuation
of an active call is a prime importance in cellular system, a new approach has been
proposed to minimize the rate of call drops and increase the quality of the network
both related to customer satisfaction and performance of cellular operator which
enhances the revenue of the company. This approach deals with the design of
increasing the number of carriers in each sector of the BTS (Base Transceiver Station),
which reduces call drops to a greater extent even during peak hours. The optimization
in radio frequency planning is done by increasing the number of carriers in each sector
of the BTS. This planning process is done using a commercial tool called “ATOLL
(Acceptance Test Or Launch Language) TOOL”, which is a 64-bit multi-technology
wireless network design and optimization platform. This includes the coverage,
capacity and frequency planning of RF network, which in turn covers the vast area
effectively. Initially, an effective frequency planning is done for 900MHz BTS (Base
Transceiver Station) sites with a set of BSIC (Base station Identity Code), BCCH
(Broadcast channel), MAL frequency (Mobile Allocation List) and MAIO (Mobile
Allocation Index List).
v
TABLE OF CONTENTS
CHAPTER
NO.
TITLE PAGE NO.
ABSTRACT
iv
LIST OF TABLES viii
LIST OF FIGURES ix
LIST OF ABBREVIATIONS x
1 INTRODUCTION 1
1.1 INTRODUCTION TO MOBILE
COMMUNICATION
1
1.2 DUPLEXING
METHODOLOGY
2
1.2.1 Frequency Division Duplex 2
1.2.2 Time Division Duplex 2
1.3 MULTIPLE ACCESS
TECHNOLOGIES
2
1.3.1 Frequency Division Multiple
Access
3
1.3.2 Time Division Multiple Access 3
1.3.3 Code Division Multiple Access 4
1.4 OVERVIEW OF GSM
NETWORK
4
1.5 GSM ARCHITECTURE 5
1.5.1 Network and Switching
subsystem
6
1.5.1.1 Mobile Switching Centre 6
vi
1.5.1.2 Home Location Register 6
1.5.1.3 Visitor Location Register 6
1.5.1.4 Equipment Identity
Register
7
1.5.2 Operation and Maintenance
Centre
7
1.5.3 Base Station Subsystem 8
1.5.3.1 Base Transceiver Station 8
1.5.3.2 Base Station Controller 8
1.5.4 Mobile Station 8
1.5.4.1 The Terminal 9
1.5.4.2 The SIM 9
1.6 GEOGRAPHICAL AREAS OF
THE GSM NETWORK
9
1.7 CONTROL CHANNELS 10
1.7.1 Traffic channels 11
1.7.2 Broadcast channels 11
1.7.3 Common control channels 12
1.7.4 Dedicated control channels 13
1.8 CALL SETUP IN GSM
NETWORK
14
2 LITERATURE REVIEW 15
3 GSM NETWORK PLANNING 18
3.1 INTRODUCTION TO RF
NETWORK PLANNING
18
3.2 PLANNING PROCEDURE FOR
RF NETWORK
18
vii
3.3 CAPACITY PLANNING 19
3.3.1 Network Dimensioning 19
3.3.2 Capacity calculation 20
3.3.3 Structure of Erlang B table 21
3.3.4 Frequency reuse schemes 22
3.3.5 Power budget calculations 23
3.4 COVERAGE PLANNING 23
3.5 FREQUENCY PLANNING 24
3.5.1 Frequency reuse 24
3.5.2 Frequency hopping 25
3.5.3 Implementation of frequency
hopping
25
3.5.3.1 Hopping Sequence Number 26
3.5.3.3 Rules for using HSN and
MAIO
26
3.6 PLANNING MODELS 27
4 DESIGN AND
IMPLEMENTATION
28
4.1 SOFTWARE USED 28
4.1.1 ATOLL planning tool 28
4.2 SCENARIO DESCRIPTION 29
4.3 SAMPLE PROCESS OF
WORKING OF ATOLL TOOL
29
5 RESULTS AND DISCUSSION 35
6 CONCLUSION AND FUTURE
WORK
42
REFERENCES 43
LIST OF PUBLICATIONS 46
viii
LIST OF TABLES
TABLE NO. CAPTION PAGE NO.
3.1 Erlang B table 21
3.2 BCCH channel assignment 25
3.3 TDMA frame sequence for 2/2/2 sectors 26
5.1 OMCR report before planning 36
5.2 OMCR report after planning 38
5.3 Total traffic in Erlang 39
5.4 Total Call drops 40
ix
LIST OF FIGURES
FIGURE NO. CAPTION PAGE NO.
1.1 Access Network 1
1.2 FDMA Frame 3
1.3 TDMA Frame 4
1.4 GSM Architecture 5
1.5 GSM Network Areas 9
1.6 Channels of GSM Network 10
3.1 RF Planning Process 19
4.1 New document 29
4.2 Digital Map import 30
4.3 Clutter Properties 30
4.4 Vectors import 31
4.5 Importing places 31
4.6 BTS Properties configured 32
4.7 Propagation model
configured
32
4.8 BCCH Assignment 33
4.9 Signal strength for 4 BTS 33
4.10 C/I level of 4 BTS 34
5.1 Area under Test 35
5.2 Signal Level of Area Under
Test
37
5.3 C/I Level of Area under Test 38
x
LIST OF ABBREVIATIONS
AGCH Access Grant Channel
ARFCN Absolute Radio Frequency Channel Number
ATOOL Acceptance, Test Or Launch Language
AUC Authentication Centre
BCCH Broadcast Control Channel
BSC Base Station Controller
BSS Base Station Subsystem
BTS Base Transceiver Station
CBCH Cell Broadcast Channel
CDMA Code Division Multiple Access
EIR Equipment Identity Register
FCCH Frequency Correction Channel
FDMA Frequency Division Multiple Access
GSM Global System for Mobile
HLR Home Location Register
HSN Hopping Sequence Number
ISDN International Service Digital Network
LAI Location Area Identity
LU Location Updation
MAIO Mobile Allocation and Index Offset
MS Mobile Station
MSC Mobile Switching Centre
MSISDN Mobile Station International Service Digital Network
MSRN Mobile Station Roaming Number
xi
ND Network Dimensioning
NSS Network Switching and Subsystem
OMC Operation and Maintenance Centre
OMCR Operation Maintenance Control and Radio Network
PCH Paging Channel
PLMN Public Land Mobile Network
PSTN Public Switched Telephone Network
QOS Quality Of Service
RACH Random Access Channel
SCH Synchronization Channel
SIM Subscriber Identity Module
TCH Traffic Channel
TDMA Time Division Multiple Access
TMSI Temporary Mobile Subscriber Identity
VLR Visitor Location Register
1
CHAPTER-1
INTRODUCTION
1.1Introduction to Mobile Communication:
In Telecom network conventionally each user is connected to the Telephone
exchange individually. This dedicated pair starts from MDF, where it is connected to
the appropriate Equipment point and ends at the customer premises Telephone. (With
flexibility at cabinet/pillar/ distribution points DPs)
Fig 1.1. Access network
The connectivity from exchange to customer premises is called “Access
Network or Local Loop”, and mostly comprises of underground cable from exchange
up to DP‟s and insulated copper wires (Drop Wires) later on This type of Access
Network does not require separate Authentication of customer before extending
services. Whenever the cable capacity has reached the maximum additional cable is
laid to augment the capacity. Even though there are advantages in introducing wireless
connectivity in Subscriber‟s loop, we have to tackle certain issues viz,
1. Duplexing methodology.
2. Multiple Access methods.
3. Cellular principle or reuse concept.
4. Techniques to cope with “mobile” environment.
2
1.2 Duplexing Methodology:
Duplexing is the technique by which the send and receive paths are separated
over the medium, since transmission entities (modulator, amplifiers, demodulators)
are involved.
There are two types of duplexing.
• Frequency Division Duplexing (FDD)
•Time Division Duplexing (TDD)
1.2.1 Frequency Division Duplexing (FDD):
Different Frequencies are used for send and receive paths and hence there will
be a forward band and reverse band. Duplexer is needed if simultaneous transmission
(send) and reception (receive) methodology is adopted .Frequency separation between
forward band and reverse band is constant
1.2.2 Time Division Duplexing (TDD):
TDD uses different time slots for transmission and reception paths. Single radio
frequency can be used in both the directions instead of two as in FDD. No duplexer is
required. Only a fast switching synthesizer, RF filter path and fast antenna switch are
needed. It increases the battery life of mobile phones.
GSM and CDMA systems use Frequency Division Duplexing and correct uses
Time Division Duplexing.
1.3 Multiple Access methodologies:
The technique of dynamically sharing the finite limited radio spectrum by
multiple users is called Multiple Access Technique. By adopting multiple access
techniques all users cannot get the services simultaneously and some amount of
blocking is introduced by the system. This is known as GOS (Grade of Service).
Generally there are three different types of multiple access technologies. They
are
• Frequency Division Multiple Access (FDMA)
• Time Division Multiple Access (TDMA)
• Code Division multiple Access (CDMA)
3
1.3.1 Frequency Division Multiple Access (FDMA):
FDMA is a familiar method of allocating bandwidth, where a base station is
allowed to transmit on one or more number of preassigned carrier frequencies and a
mobile unit transmits on corresponding reverse channels. No other base station within
range of the mobile will be transmitting on the same forward channel, and no other
mobile within range of the base station should be transmitting on the same reverse
channel. Both the base and the mobile usually transmit continuously during a
conversation, and fully occupy their assigned forward and reverse channels. No other
conversation can take place on these channels until the first conversation is completed.
Fig 1.2. FDMA Frame
1.3.2 Time Division Multiple Access (TDMA):
TDMA is a more efficient, but more complicated way of using FDMA
channels. In a TDMA system each channel is split up into time segments, and a
transmitter is given exclusive use of one or more channels only during a particular
time period. A conversation, then, takes place during the time slots to which each
transmitter (base and mobile) is assigned. TDMA requires a master time reference to
synchronize all transmitters and receivers.
4
Fig 1.3. TDMA Frame
1.3.3 Code Division Multiple Access (CDMA):
CDMA is fundamentally different than TDMA and FDMA. Where FDMA and
TDMA transmit a strong signal in a narrow frequency band, CDMA transmits a
relatively weak signal across a wide frequency band. Using a technique called direct
sequence spread spectrum, the data to be transmitted are combined with a pseudo-
noise code (a pre-determined binary sequence that appears random) and transmitted
broadband. CDMA under Interim Standard 95 uses a bandwidth of 1.25 MHz The
pseudo-noise code (PN code) is a series of binary "chips" that are much shorter in
duration than the data bits. Since the chips appear to be in a random pattern, and there
are many chips per data bit (in IS-95 there are 128 chips for each data bit), the
modulated result appears to normal (FDMA) receivers as background noise.
1.4 Overview of GSM
Global System for Mobile Communication (GSM) is a globally accepted standard for
digital cellular communication. GSM is the name of a standardization group established
in 1982 to create a common European mobile telephone standard that would formulate
5
specifications for a pan-European mobile cellular radio system operating at 900 MHz.
GSM was devised as a cellular system specific to the 900 MHz band, called "The Primary
Band". The primary band includes two sub bands of 25 MHz each, 890 to 915 MHz and
935 MHz to 960 MHz. A GSM network is composed of several functional entities, whose
functions and interfaces are specified as,
Uplink frequency band: 890 to 915 MHz (MS transmits, BTS receives).
Downlink frequency band: 935 to 960 MHz (BTS transmits, MS receives).
1.5 GSM ARCHITECTURE
The GSM network is divided into four major systems
Network and switching subsystem(NSS)
Operation and maintenance centre(OMC)
Base station Subsystem(BSS)
Mobile station(MS)
Fig 1.4. GSM Architecture
6
1.5.1 Network and switching subsystem (NSS):
The NSS is responsible for performing call processing and subscriber-related
functions. The switching system includes the following functional units
Mobile Switching centre
Home location register
Visitor location register
Equipment identity register
Authentication centre
1.5.1.1 Mobile Switching Centre (MSC):
MSC performs all switching functions for all mobile stations, located in the
geographic area controlled by its assigned BSS‟s. Also it interfaces with PSTN, with
other MSC‟s and other system entities.
1.5.1.2 Home Location Registers (HLR):
It contains
The identity of mobile subscriber called IMSI
ISDN directory number of mobile station
Subscription information on services
Service restrictions.
1.5.1.3 Visitor Location Registers (VLR):
The VLR always integrated with the MSC. When a mobile station roams into a
new MSC area, the VLR connected to that MSC would request data about the mobile
station from the HLR. Later, if the mobile station makes a call, the VLR will have the
information needed for call setup without having to interrogate the HLR.
7
1.5.1.4 Equipment Identity Registers (EIR):
Equipment identity register consists of identity of mobile station equipment
called IMEI, which may be valid, suspect and prohibited. The information is available
in the form of three lists.
White list-The terminal which is allowed to connect to the network.
Black list-The terminal reported as stolen are not kept approved. They
are not allowed to connect to the network.
Grey list-The grey list consists of the IMEI numbers of the devices
which are outside of the white and black lists and of which electronic
communication connections are open.
1.5.1.5 Authentication Centre:
It is associated with the HLR. It stores an identity key called Ki for each
mobile subscriber. This key is used to generate the authentication
triplets.
It is authenticated using a RAND (random number).
It consists of SRES(signed response)-to authenticate IMSI.
Also, it has another key called Kc (Cipher key) to cipher
communication over the radio path between the MS and the network.
1.5.2 Operation and Maintenance Centre (OMC):
The OAM function allows the operator to monitor and control the system as
well as to modify the configuration of the elements of the system. Not only the OSS is
part of the OAM, also the BSS and NSS participate in its functions as it is shown in
the following examples:
• The components of the BSS and NSS provide the operator with all the
information it needs. This information is then passed to the OSS which is in charge of
analyzing it and control the network.
• The self-test tasks, usually incorporated in the components of the BSS and
NSS, also contribute to the OAM functions.
8
• The BSC, in charge of controlling several BTSs, is another example of an
OAM function performed outside the OSS.
1.5.3 Base Station Subsystem (BSS):
The BSS connects the Mobile Station and the NSS. It is in charge of the
transmission and reception. The BSS can be divided into two parts:
1.5.3.1 The Base Transceiver Station (BTS):
The BTS corresponds to the transceivers and antennas used in each cell of the
network. A BTS is usually placed in the centre of a cell. Its transmitting power defines
the size of a cell. Each BTS has between one and sixteen transceivers depending on
the density of users in the cell.
1.5.3.2 The Base Station Controller (BSC):
The BSC controls a group of BTS and manages their radio resources. A BSC is
principally in charge of handovers, frequency hopping, exchange functions and
control of the radio frequency power levels of the BTSs.
Characteristics of the Base Station System (BSS) are:
• The BSS is responsible for communicating with mobile stations in cell areas.
• One BSC controls one or more BTSs and can perform inter-BTS and intra-
BTS handovers.
• The BTS serves one or more cells in the cellular network and contains one or
more TRXs (Transceivers or radio units).
• The TRX serves full duplex communications to the MS.
1.5.4 Mobile Station (MS):
A Mobile Station consists of two main elements:
9
1.5.4.1 The Terminal:
There are different types of terminals distinguished principally by their power
and application:
• The `fixed' terminals are the ones installed in cars. Their maximum allowed
output power is 20 W.
• The GSM portable terminals can also be installed in vehicles. Their maximum
allowed output power is 8W.
• The handheld terminals have experienced the biggest success thanks to the
weight and volume, which are continuously decreasing. These terminals can emit up
to 2 W. The evolution of technologies allows decreasing the maximum allowed power
to 0.8 W.
1.5.4.2 The SIM:
The SIM is a smart card that identifies the terminal. By inserting the SIM card
into the terminal, the user can have access to all the subscribed services. Without the
SIM card, the terminal is not operational. The SIM card is protected by a four-digit
Personal Identification Number (PIN). In order to identify the subscriber to the
system, the SIM card contains some parameters of the user such as its International
Mobile Subscriber Identity (IMSI). Another advantage of the SIM card is the mobility
of the users. In fact, the only element that personalizes a terminal is the SIM card.
Therefore, the user can have access to its subscribed services in any terminal using its
SIM card.
1.6 GEOGRAPHICAL AREAS OF THE GSM NETWORK
Fig 1.5. GSM network areas
10
The figure 1.5 represents the different areas that form a GSM network. As it
has already been explained a cell, identified by its Cell Global Identity number (CGI),
corresponds to the radio coverage of a base transceiver station. A Location Area (LA),
identified by its Location Area Identity (LAI) number, is a group of cells served by a
single MSC/VLR. A group of location areas under the control of the same MSC/VLR
defines the MSC/VLR area. A Public Land Mobile Network (PLMN) is the area
served by one network operator.
1.7 Control channels:
One or more logical channel scan be transmitted on a physical channel. There
are different types of logical channels. The type of logical channel is determined by
the function of the information transmitted over it.
The following types of logical channels exist:
Traffic channels
Broadcast channels
Common control channels
Dedicated control channels
Note that the first channel type carries speech and data, and the other types
control information (signalling).
Fig 1.6. Channels of GSM Network
11
1.7.1 TRAFFIC CHANNELS
The traffic channels are used to send speech or data services. There are two
types of traffic channels. They are distinguished by their transmission rates.
The following traffic channels are provided:
TCH/F (Traffic Channel Full rate)
The TCH/F carries information at a gross bit rate of 22.8 kbit/s (after channel
coding). The net (or effective) bit rate at the TCH/F is for speech 13 kbit/s and for data
12, 6 or 3.6 kbit/s (before channel coding). The transmission rates of the data services
allow services which are compatible to the existing, respectively, 9.6, 4.8 and 2.4
kbit/s PSTN and ISDN services.
TCH/HR (Traffic Channel Half rate)
The TCH/H carries information at a gross bit rate of 11.4 kbit/s. The net bit rate
at the TCH/H is for speech 5.6 kbit/s and for data 6 or 3.6 kbit/s.
TCH/EFR (Enhanced Full rate)
The EFR provides a voice coding algorithm offering improved speech quality.
The algorithm is fully compatible with a BSM speech quality. The algorithm is fully
compatible with a GSM 13 kbit/s speech channel. The main benefit will be improved
voice quality which offers prospects to compete with PSTN networks.
1.7.2 BROADCAST CHANNELS
The information distributed over the broadcast channels helps the mobile
stations to orient themselves in the mobile radio network. The broadcast channels are
point-to-multipoint channels which are only defined for the downlink direction (BTS
to the mobile station). They are four types:
BCCH (Broadcast Control Channel)
The mobile station is informed about the system configuration parameters (for
example Local Area Identification, Cell Identity and Neighbour Cells). Using this
12
information the mobile stations can choose the best cell to attach to. The BCCH is also
known as beacon.
FCCH (Frequency Correction Channel)
To communicate with the BTS the mobile station must tune to the BTS. The
FCCH transmits a constant frequency shift of the radio frequency carrier that can be
used by the mobile station for frequency correction.
SCH (Synchronization Channel)
The SCH is used to time synchronize the mobile stations. The data on this
channel carries the TDMA frame number and the BSIC (Base Station Identity Code).
CBCH (Cell Broadcast Channel)
The CBCH is used for the transmission of generally accessible information
(Short Message Service messages) in a cell, which can be polled by the mobile station.
1.7.3 COMMON CONTROL CHANNELS
Common control channels are specified as point-to-multipoint channels which
only operate in one direction of transmission, either in the uplink or downlink
direction. There are three types:-
PCH (Paging Channel)
The PCH is used in the downlink direction for paging the mobile stations.
AGCH (Access Grant Channel)
The AGCH is also used in the downlink direction. A logical channel for a
connection is allocated via the AGCH if the mobile station has requested such a
channel via the RACH.
13
RACH (Random Access Channel)
The RACH is used in the uplink direction by the mobile stations for requesting
a channel for a connection. It is an access channel that uses the slotted Aloha access
scheme.
1.7.4 DEDICATED CONTROL CHANNELS
Dedicated control channels are full-duplex, point-to-point channels. They are
used for signaling between the BTS and a certain mobile station.
SACCH (Slow Associated Control Channel)
The SACCH is a duplex channel which is always allocated to a TCH or
SDCCH. The SACCH is used for transmission of signaling data, radio link
supervision measurements, transmit power control and timing advance data. Note that
the SACCH is only used for non-urgent procedures.
FACCH (Fast Associated Control Channel)
The FACCH is used as a main signalling link for the transmission of signalling
data (for example handover commands). It is also required for every call set-up and
release. During the call the FACCH data is transmitted over the allocated TCH instead
of traffic data; this is marked by a flag called a stealing flag. The process of stealing a
TCH for FACCH data is called pre-emption.
SDCCH (Stand-alone Dedicated Control Channel)
The SDCCH is a duplex, point-to-point channel which is used for signaling in
higher layers. It carries all signaling between the BTS and the mobile station when no
TCH is allocated. The SDCCHs are used for service requests (for example Short
Message Service), location updates, subscriber authentication, ciphering initiation,
equipment validation and assignment to a TCH. The net SDCCH bit rate is about 0.8 k
bit/s.
14
1.8 CALL SETUP IN GSM NETWORK
The successful call set up consists of two procedures. First procedure is
Immediate Assignment procedure which is used to create a signaling connection
between the Mobile station (MS) and the network. It can be initiated only by the MS
sending a CHANNEL REQUEST message on the Random Access channel (RACH)
to the BTS that it requires a signaling channel (SDCCH). This message contains the
information field establishment cause and random reference. The establishment cause
gives the reason why the MS is requesting a SDCCH. Possible reasons are emergency
call, call re-establishment, originating speech call and location updating. The
successful seizure of SDCCH is acknowledged by sending the Establish Indication
message from MS to BTS and then to BSC. Further coordination procedure
(authentication, ciphering etc.) are now performed on the SDCCH. Second procedure
is Assignment procedure which is used to occupy a radio resource (speech channel).
The MSC is initiator of this procedure. The MSC sends an ASSIGNMENT
REQUEST message to the BSC requesting the assignment of a radio resource (RR).
Then it comes next signalization between BTS and BSC in order to allocate and
activate a suitable traffic channel. If the TCH is successfully seizure by MS, the BSC
sends the ASSIGNMENT COMPLETE message.
The main reasons for unsuccessful call setups in mobile networks are lack of
radio coverage (either in the downlink or the uplink), radio interference between
different subscribers, imperfections in the functioning of the network (such as failed
call setup redirect procedures), overload of the different elements of the network (such
as cells), etc.
15
CHAPTER-2
LITERATURE REVIEW
[1] “Effective Frequency Planning to Achieve Improved KPI’S, TCH and
SDCCH Drops for a Real GSM Cellular Network”, The drastic development in the
field of wireless communications has resulted huge demand for voice and data
communication in public domain but spectrum is the major concern and scarce
resources which imposes a high cost on the data transmission. The objective is to
provide a quality communication to maximum number of users. The number of users
supported by system can be increased by using more Frequencies, hence efficient RF
(radio frequency) planning is required to maximize the limited spectrum resources.
One has to look for optimum compromise between dense reuse with least interference.
To establish the quality communication, we investigate KPI (key performance
indicators), TCH (traffic channel) and SDCCH (stand alone dedicated control
channel) drop on 93 GSM sites for a cellular operator in a city of India. An efficient
frequency planning approach practically with limited spectrum availability and
BCCH-BSIC (broad cast channel- Base station Identity code) set of frequencies, MAL
(mobile allocation list) and DCHNO (TCH) frequency with NCCPERM (national
color code permitted) parameter are used for least interference is designed. With the
help of Google Earth and simulation software to practically implement these change
values in field data. The significant improvements in KPl's, TCH drop and SDCCH
drop which outperform the previous frequency plan have been found.
[2] “A Practical Approach of Planning and Optimization for Efficient Usage of
GSM Network On the Performance of Largest-Deficit-First for Scheduling Real-
Time Traffic in Wireless Networks”, In this paper, the planning of wireless
networks is vital if operators wish to make full use of the existing investments. This
paper deals with a practical approach of radio network planning process for efficient
usage of GSM network. The key performance indicator (KPI) and drive test report of
16
a Bangladeshi operator “Teletalk Bangladesh Limited” are used to make proposals on
how operators can optimize radio resources as well as provide the required QoS to the
subscribers. This study would help to plan operators to enhance coverage, improve
quality and increase capacity in the days to come.
[3] “A Design Approach to Maximize Handover performance Success Rate and
Enhancement of voice Quality Samples for a GSM Cellular Network”,
Continuation of an active call is of prime importance in the cellular systems. In this
paper a new approach has been designed to maximize handover success rate (HOSR)
and voice quality for a GSM cellular network both related to customer satisfaction and
performance of cellular operator which enhances revenue of the company. Initially, an
effective frequency planning is done for GSM 1800 MHz BTS (base transreceiver
station) sites, where a set of BCCH frequency (broad cast channel) - BSIC (base
station identity code), MAL frequency (mobile allocation list) with MAIO (mobile
allocation index offset) and HSN (hopping sequence no) is used. Afterwards to
improve handover, neighbor list verification is done and unnecessary neighbors are
deleted. Neighbors define within the first tear of base cell with the help of commercial
tool. the help of Google Earth and simulation software to practically implement these
changed values in the mobile industry field.
[4]“Scheduling in Successive Interference Cancellation based Wireless Ad Hoc
Networks”, Successive Interference Cancellation (SIC) allows multiple transmissions
in the same neighbourhood by enabling both concurrent reception and interference
rejection via decoding and subtracting the signals successively from the composite
received signal. In this paper, they studied the scheduling problem for minimizing the
schedule length required to satisfy the traffic demands of the links in SIC based
wireless ad hoc networks. Upon proving the NP-hardness of the problem, they
proposed a novel efficient heuristic scheduling algorithm based on the greedy
assignment of the links to each time slot by using a novel metric called Interference
Effect (IE). The IE of a feasible link is defined as the total Signal-to-Interference-plus-
17
Noise Ratio (SINR) drop of the links in the scheduled set with the addition of that
link. They demonstrate via extensive simulations that the proposed algorithm
performs better than the previous algorithms, with lower computational complexity.
[5] “Throughput–Delay Trade off in Interference-Free Wireless Networks With
Guaranteed Energy Efficiency”, Existing works have addressed the tradeoffs
between any two of the three performance metrics: throughput, energy efficiency
(EE), and delay. In this paper, they unveil the intertwined relations among these three
metrics under a unifying framework and particularly investigate the problem of EE-
guaranteed throughput–delay trade-off in interference-free wireless networks. They
first propose two admission control schemes, referred to as the first-out and first-in
schemes. Then formulate it as two stochastic optimization problems, aiming at
throughput maximization (in the first-out scheme) or dropping rate minimization (in
the first-in scheme) subject to requirement of EE, stability, admission control, and
transmit power. To solve the problems, the EEGuaranteed algorithm for throughput-
delay trade off (eGuard), respectively called eGuard-I and eGuard-II in the first-out
and first-in schemes, is devised. Moreover, with guaranteed RoE, They theoretically
showed that the eGuard (I and II) can not only push the throughput arbitrarily close to
the optimal with tradeoffs in delay but also quantitatively control the throughput–
delay performance on demand. Simulation results consolidate the theoretical analysis
and particularly show the pros and cons of the two schemes.
[6] "Impact of mobility on call block, call drops and optimal cell size in small cell
networks", Assuming Poisson call arrivals at random positions with random
velocities, they have discussed about the characterization of handovers at the
boundaries. In this paper, the explicit expressions for call block and call drop
probabilities using tools from spatial queuing theory have been derived. These
expressions are used to derive optimal cell sizes for various profiles of velocities in
small cell networks via some numerical examples.
18
CHAPTER-3
GSM NETWORK PLANNING
3.1. Introduction to RF Network Planning
Achieving maximum capacity while maintaining an acceptable grade of service
and good speech quality is the main issue for the network planning. Planning an
immature network with a limited number of subscribers is not the real problem. The
difficulty is to plan a network that allows future growth.
3.2 Planning procedure for RF network
Planning means building a network able to provide service to the customers
wherever they are need. For a well-planned cell network a planner should meet the
following requirements
• Coverage as required and predicted.
• Co channel and adjacent channel interference levels as predicted for maintaining
good quality of service.
• Minimum antenna adjustments during the optimization process.
• Maximizing the network capacity (Erl/km2) with limited frequency band (MHz) by
reusing the same frequencies.
• Minimum changes to the BSS parameters/database during the optimization phase.
• Facilitate easy expansion of the network with minimal changes in the system.
In general the planning process starts with the inputs from the customer. The customer
inputs include customer requirements business plans system characteristics and any
other constraints. After the planned system is implemented the assumptions made
19
during the planning process to be validated and corrected wherever necessary through
an optimization process.
RF Planning is divided in to three parts:
• Capacity Planning
• Frequency Planning
• Coverage Planning
Fig 3.1. Radio Frequency planning process
3.3 Capacity Planning
3.3.1 Network dimensioning
Network Dimensioning (ND) is usually the first task to start the planning of a
given cellular network. The main result is an estimation of the equipment necessary to
meet the following requirements.
• Capacity
• Coverage
• Quality
ND gives an overall picture of the network and is used as a base for all further
planning activities.
20
Network dimensioning inputs are
• Capacity related
o Spectrum available.
o Subscriber growth forecast
o Traffic density map (Traffic per subs)
• Coverage related
o Coverage regions
o Area types information
• Quality related
o MS classes
o Blocking probability
o Location probability
o Redundancy
o Indoor coverage.
The operator normally supplies the input data, but use of defaults is also possible.
The technical parameter and characteristics of the equipment to be used are another
very important part of the input. This includes the basic network modules as well as
some additional elements.
3.3.2 Capacity calculation
The capacity of a given network is measured in terms of the subscribers or the
traffic load that it can handle. The former requires knowledge of subscriber calling
habits while the latter is more general.
The steps for calculating the network capacity are
• Find the maximum no of carriers per cell that can be reached for the different
regions based on the frequency reuse patterns and the available spectrum.
21
• Calculate the capacity of the given cell using blocking probability and the number of
carriers.
• Finally the sum of all cell capacities gives the network capacity.
Spectrum Efficiency= BAn
s
S - Total spectrum available
n - Reuse factor
A - Cell area
B - Channel bandwidth
3.3.3 Structure of Erlang B table
Fig 3.2. Erlang B table structure
Example:
At 2% blocking (0.02 GoS), 2 traffic channels can carry 0.2235 erlangs of traffic
Table 3.1 Erlang B table
22
To calculate the capacity, refer Fig 3.2 for the given cell using blocking
probability and the number of carriers we need the well-known Erlang B table or
formulas and the no of traffic channels for different number of carriers. The result we
get is the traffic capacity in Erlangs, which can easily be transferred into the number
of subscribers.
Each TDMA frame consists of 8time slots. One for signaling information
and Remaining 7 time slots for TCH (Traffic channel) For example: consider 1 carrier
for 3 sector 1|1|1
TCH = 7
Traffic per sector = 2.935E X 3 = 8.82E
Traffic generated per user:
Rural = 1.5/60 = 0.25E
Urban = 2.4/60 = 0.04E
Traffic per BTS (Rural) = 8.82/0.25 =352.8
Given , If the total traffic = 700E
1BTS traffic = 2.935E
No of BTS = 700/8.82 = 79.365
Total user = 79.365 X 352.8 = 28000
3.3.4 Frequency reuse schemes
A cellular network can easily be drawn as a combination of hexagons or circles
by the help of regular grids. One of the advantages is the possibility to try different
frequency reuse patterns and calculate the expected co-channel interference. This is
required to assign a frequency reuse no to any of the network regions area types. It is
clear that the high-density regions are the most problematic parts of the network.
23
3.3.5 Power budget calculations
To guarantee a good quality in both directions the power of BTS and MS
should be in balance at the edge of the cell. The main idea behind the power budget
calculations is to receive the maximum output power level of BTS transmitter as a
function of BTS and MS sensitivity levels, MS output power, antenna gain, diversity
reception, cable loss, combiner loss. The power budget calculations provides
following useful results:
BTS transmitted power: BTS transmitted power is adjusted to provide a
balanced radio link for given BTS and MS receiver performance, MS
transmitter performance, antenna and feeder cable characteristics.
Isotropic path loss: this is the maximum path loss between BTS and MS
according to given radio system performance requirements.
Coverage threshold: downlink signal strength at coverage area border for
given location probability.
Cell range for indoor and outdoor coverage: this is a rough indication about
cell range in different area types and can be used for network dimensioning. It
can also be used for comparing the effect of different equipment specification
and antenna heights for the cell range.
3.4 Coverage Planning
The objective of coverage planning phase in coverage limited network areas is
to find a minimum amount of cell sites with optimum locations for producing the
required coverage for the target area. Coverage planning is normally performed with
prediction modules on digital map database. The basic input information for coverage
planning includes:
• Coverage regions
• Coverage threshold values on per regions
24
• Antenna, Preferred antenna line system specifications
3.5 Frequency Planning
The main goal of the frequency-planning task is to increase the efficiency of
the spectrum usage, keeping the interference in the network below some predefined
level. Therefore it is always related to interference predictions.
There are two basic approaches to solve the frequency assignment problem.
• Frequency reuse patterns
• Automatic frequency allocation
Some software‟s are used with automatic frequency allocation algorithms for
finding the optimum solutions. The frequency allocation is generally guided by the
following information:
• Channel requirement on cell basis according to the capacity planning
• Channel spacing limitations according to BTS specification
• Quality of service requirement which is conserved to acceptable interference
probability
• Traffic density distribution over the service area
• Performance of advanced system features
The frequency allocation is based on cell-to-cell interference probability estimation
according to the network topology, field strength distribution and traffic load.
3.5.1 Frequency Reuse
A frequency used in one cell can be reused in another cell at a certain distance.
This distance is called reuse distance. The advantage of digital system is that they can
reuse frequencies more efficiently than the analogue ones, i.e. the reuse distance can
be shorter, and the capacity increased. A cellular system is based in reuse of
25
frequencies. All the available frequencies are divided into different frequency groups
so that a certain frequency always belongs to a certain frequency group. The
frequency groups together form a cluster.
3.5.2 Frequency hopping
Frequency hopping is a method of transmitting radio signals by rapidly
switching a carrier among many frequency channels, using a pseudorandom
sequence known to both transmitter and receiver.
3.5.3 Implementation of frequency hopping
Each call has its time slots transmitted in sequence across a defined set of
hopping frequencies. Frequency hopping occurs between time slots: a mobile station
transmits or receives on a fixed frequency during one time slot, then changes
frequency before the time slot on the next TDMA frame. The total number of
available hopping sequences is 64 multiplied by the number of hopping frequencies.
Hopping sequences are described per channel by two network parameters: HSN and
MAIO. GSM uses FDMA/TDMA techniques for frequency allocation. Totally 125
carriers used in GSM Absolute Radio Frequency Carrier Number (ARFCN) uses 124
carriers and remaining 1 carrier acts as guard band. As per Telecom Regulatory
Authority of India (TRAI), Maximum 4 operators can be served in 1Band.Therefore,
124/4 = 31 carriers .31 carries are spitted into : 15 carriers (BCCH) + 16carriers (Non-
BCCH) Maximum of 1 BCCH in one sector. For example: Consider ARFCN no. is
assigned from 1 to 15
Table 3.2 BCCH Chanel Assignment
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
26
3.5.3.1 HSN
HSN (Hopping Sequence Number) defines a number that is fed into the
frequency hopping algorithm to generate the hopping sequence. Values can be 0 to 63.
Value 0 defines cyclic hopping and all other values generate a random sequence.
3.5.3.2 MAIO
MAIO (Mobile Allocation Index Offset) defines the starting frequency, or
offset, the transmission will start on within a hopping sequence. The value can be 0 to
N-1 where N is the number of allocated frequencies.
3.5.3.3 Rules for using HSN and MAIO
To fight the interference with frequency hopping, use the following rules:
• Two channels with the same HSN but different MAIO never use the same frequency
at the same time.
• Channels in the same cell using the same hopping frequency set should have the
same HSN, and different MAIO, to avoid co-channel interference within the cell.
• If random hopping is used, each channel in distant cells using the same frequency set
should have a different HSN, this optimizes the benefits of interference diversity.
Table 3.3 TDMA Frame sequence for 2|2|2 sectors
SECTORS MAIO TDMA
FRAME
1 2 3 4
A1 _ 1 1 1 1
A2 0 16 17 18 19
B1 _ 6 6 6 6
B2 2 18 19 20 21
C1 _ 11 11 11 11
C2 4 20 21 22 23
Where, A1, B1, C1 – BCCH carriers and A2, B2, C2 –NON-BCCH carriers
27
• Between the sectors the difference should be 2 or more
• Each sector difference is 3 or more
3.6 Planning models
Propagation in land mobile service at frequencies from 300 to 1800MHz is
affected in varying degrees by topography, morphography, ground constants and
atmospheric conditions. A very common way of propagation loss presentation is the
usage of so called propagation curves, normally derived from some measurement
formulae are
• Okumara Y. and others, for field strength and its variability in VHF and UHF land
Mobile Radio Service
• Hata. M, Empirical formula for Propagation Loss in Land Mobile Radio Services.
• Cost –207, Digital Land Mobile Radio Communication.
• Cost-231, Urban Transmission Loss for Mobile Radio in the 900 and 1800MHz
bands.
.
28
CHAPTER- 4
DESIGN AND IMPLEMENTATION
4.1 SOFTWARE USED
Acceptance, Test or Launch Language (ATOLL version3.2.1)
4.1.1 ATOLL planning tool
Atoll is a scalable and flexible multi-technology network design and
optimization platform that supports wireless operators throughout the network
lifecycle, from initial design to densification and optimization.
Atoll is also an open technical information system that easily integrates with
other IT applications and increases productivity. It features advanced
development tools and open interfaces that enable the integration of customized
or commercially available complementary modules.
Atoll is designed to work in a wide range of implementation scenarios, from
standalone to enterprise-wide server-based configurations using distributed and
parallel computing.
Atoll includes advanced multi-technology network planning features and a
combined Single-RAN Multi-RAT GSM/ UMTS/LTE Monte-Carlo simulator
and traffic model. Atoll supports GSM/GPRS/EDGE, UMTS/HSPA, LTE,
CDMA2000 1xRTT/EV-DO, TD-SCDMA, WiMAX, and Microwave link
networks; it also includes a high- performance propagation calculation engine,
and state- of-the-art network planning and analysis features. It has a set of fully
integrated AFP (Automatic Frequency Planning) tools and ACP (Automatic
Cell Planning) tools, allowing operators to perform design and optimization
tasks from a single application using a single database and IT infrastructure.
Optimization tools are available for GSM, UMTS, LTE and WiMAX
29
4.2 Scenario Description
In second generation systems, detailed planning concentrated strongly on coverage
planning and capacity analysis than simple coverage optimization is needed. The tool should
aid the planner to optimize the base station configurations, the antenna selections and antenna
directions and even the site locations, in order to meet the quality of service and the capacity
and service requirements at minimum cost.
4.3 SAMPLE PROCESS OF WORKING OF ATOLL TOOL:
Creating a new document
Fig 4.1. New document
30
Importing Digital Map
Fig 4.2. Digital Map import
Importing Clutter Properties
Fig 4.3. Clutter Properties
31
Importing digital terrain model
Fig 4.4. Vectors import
Importing Places
Fig 4.5. Importing places
32
BTS Configuration
Fig4.6. BTS Properties configured
Propagation model configuration
Fig 4.7. Propagation model configured
33
BCCH Assignment
Fig 4.8. BCCH Assignment
Frequency planning for 4 BTS:
Fig 4.9. Signal strength for 4 BTS
34
Fig 4.10. C/I level of 4 BTS
The frequency planning of 4BTS covers in and around areas of guindy, which
covers about 2km radius approximately. In this area, signal strength and C/I level are
measured intentionally since they are the prime factors of reducing the number of call
drops which stands as a major issue in telecommunication network.
There are two types of tests are carried out for analysis.
1. Hotspot test
2. Drive test
Hotspot test:
The test made using setup, which includes 2 mobile phones, GPs, laptop is
carried out in a same place without mobility. Here, the handovers does not take
place.
35
Drive Test:
As the analysis of the network before planning is being carried out by
travelling/moving on the route, the testing equipments and tools are taken by a
vehicle, hence called as drive test. Here, handovers takes place.
There are 2 types of calls made in hotspot test and drive test. They are:
1. Long call
2. Short call
Long call:
The call is connected to the server without specifying any duration. The call is
being cut when the caller themselves cuts the call.
Short call:
The call is connected to the server by giving some stipulated duration. When
the call is being cut, it automatically reconnects to the server.
36
CHAPTER-5
RESULTS AND DISCUSSIONS
The main aim of this project is to reduce the number of call drops which occurs
due to traffic. On analysis from the OMCR (Operation Maintenance Control and
Radio Network) and also by the analysis made from ATOLL TOOL before planning,
it is found that call drops occur to a greater extent. Hence, planning is made for
consideration from the above analysis to reduce number of call drops. In addition to
this analysis, drive test has been made in the region under test, which is also one of the
survey report for planning the network.
The area chosen for the test is pallavaram area under Chennai zone. Here, it is
clear that signal strength level in the network is quite low, which is indicated using
yellow colour and is shown in fig 5.1.
Fig 5.1. Area under Test
37
Table 5.1 OMCR Report before Planning
By the use of ATOLL TOOL, the signal strength and Channel to
Interference(C/I) level is analysed in the pallavaram area. Signal Strength refers to
the transmitter power output as received by a reference antenna at a distance from the
transmitting antenna. The channel to interference refers to the interference occurs
between the carriers in a single sector or the interference occur between the carriers in
different sectors
The fig.5.2 depicts the signal strength of pre-planned network, where call drop
occurs.
38
Fig 5.2. Signal Level of Area under Test
The Signal strength of GSM network ranges from -43dbm to -110dbm. In the
fig 5.2, the gray colour depicts the best signal strength of the network that is around -
50dBm and green colour depicts the optimum signal obtained from BTS which is in
the range between -70dbm to -80dbm, whereas yellow colour depicts the poor quality
of signal strength received from BTS that is below -110 dBm.
39
Fig 5.3. C/I Level of Area under Test
The fig.5.3 depicts the C/I level of pre-planned network. Generally, a standard
value for best C/I level is ≥ 9 dB where as in practical it is found to be ≥ 12 dB as a
best result. Here, gray colour represents the lowest interference range. The dark green
depicts the optimum C/I level of the network. The light green colour depicts the area
where highest interference occurs.
Table 5.2 OMCR Report after Planning
40
The OMCR report shows the pallavaram area of Chennai zone after planning
process, which is represented in Table 5.2. Here, it shows that call drops have been
reduced great in number. Also, the total traffic, call drop ratio and call block ratio has
got reduced. The call drop is nothing but fraction of telephone calls which due to technical
reason were cut off before the speaking parties had finished their conversation tone and
before one of them had hang up. Call blocking allows a subscriber to block incoming calls
from specific telephone numbers. Also to be elaborated, call blocking occurs when the
channel is not available for call process
Table 5.3 Total Traffic in Erlang
41
Table 5.4 Total Call Drops
From the results above, it is inferred that the parameters like total traffic and
total call drop are reduced to a greater extent by planning the network, in which
carriers are increased from 3/3/3 to 5/5/5 in each sector. The analysis is made by the
OMCR report taken before (Mar-18) and after (Mar-24) planning of the network,
which is taken at different time intervals.
42
CHAPTER-6
CONCLUSION AND FUTURE WORK
As a result from OMCR report and viewing the existing scenario of area under
test using ATOLL TOOL, it is found that the call drops occur in the area of
Pallavaram in Chennai zone. Also, by the study and survey, it is clear that the reason
for call drop is that RF carriers are not sufficient in each sector. Hence, capacity
planning in RF medium is done to increase the capacity of the carriers. At present, the
sector consists of 3/3/3 carriers, which allows the entry of 63 subscribers in a second.
On analysing, 2 more carriers are added in each sector which is represented as 5/5/5 to
increase the capacity of carriers. This paves a path for the entry of 105 subscribers in a
second to get into the network, which reduces the call drop effectively even during
peak hours. On increasing the carriers, the network faces the issues such as low signal
strength from BTS to MS and high interference between the carriers and sectors.
Hence, by the use of ATOLL TOOL, it is planned such that the call drops are reduced
in number, which made the network effective with increased signal strength and
reduced interference.
In future, there is an opportunity to improve the network performance by
focusing on the following factors such as the missing neighbour relations, proposing
antenna tilt changes, adjusting handover margins (Power Budget, Level, Quality, and
Umbrella HOs).
43
REFERENCES
1. Prabhjot Singh, Mithilesh Kumar, Ambarish Das (2014), “Effective Frequency
Planning to Achieve Improved KPI'S, TCH and SDCCH drops for a real GSM
Cellular Network,” IEEE Transaction.
2. Giriraj Sharma and Ashish Kumar Bansal, April 2014, “A Practical Approach
to Improve GSM Network Quality by RF Optimization”, International Journal
of Engineering and Advanced Technology (IJEAT)ISSN: 2249 – 8958,
Volume-3.
3. U S Rahman, M. A. Matin, M R Rahman, (2012) “A Practical Approach of
Planning and Optimization for Efficient Usage of GSM Network,”
International Journal of Communications (IJC) Volume 1 Issue 1.
4. Christer Johansson Jonas Naslund, Magnus Madfors, “Adaptive Frequency
Allocation of BCCH Frequencies in GSM,”IEEE Trans. on Communications,
Vol. 39, No. 12, 1995.
5. Prabhjot Singh, Mithilesh Kumar, Ambarish Das, “A Design Approach to
Maximize Handover Performance Success rate and Enhancement of voice
quality Samples for a GSM Cellular Network,” IEEE Trans. 2014.
6. Mehmet Kontik and Sinem Coleri Ergen, April 2014, „Scheduling in
Successive Interference Cancellation based Wireless Ad Hoc Networks‟, IEEE
Wireless Communications Letters, vol. 3.
7. Xiaohan Kang, Weina Wang, Juan José Jaramillo and Lei Ying, Aug 2014, „On
the Performance of Largest-Deficit-First for Scheduling Real-Time Traffic in
Wireless Networks‟, IEEE/Acm Transactions on Networking.
8. Yuzhou Li, Min Sheng, Cheng-Xiang Wang, Xijun Wang Yan Shi, and
Jiandong Li, March 2015, „Throughput–Delay Tradeoff in Interference-Free
Wirele ss Networks With Guaranteed Energy Efficiency‟, IEEE Transactions
on Wireless Communications, vol. 14, NO. 3.
9. M. Kontik and S. C. Ergen,April 2014, „Scheduling in single-hop multiple
access wireless networks with successive interference cancellation‟, IEEE
Wireless Communications Letters, vol. 3.
10. M. Yazdanpanah, S. Sebbah, C. Assi, and Y. Shayan, June 2013 „Impact of
successive interference cancellation on the capacity of wireless networks: Joint
44
optimal link scheduling and power control‟, in IEEE International Conference
on Communications (ICC).
11. S. Lv, W. Zhuang, X. Wang, C. Liu, and X. Zhou,June 2011, „Maximizing
capacity in the SINR model in wireless networks with successive interference
cancellation‟, in IEEE International Conference on Communications (ICC),
pp.1–6.
12. K. Son, H. Kim, Y. Yi, and B. Krishnamachari,Sep 2011, „Base station
operation and user association mechanisms for energy-delay tradeoffs in green
cellular networks‟, IEEE J. Sel. Areas Commun., vol. 29, no. 8, pp. 1525–1536.
13. I.-H. Hou and P. R. Kumar, 2010 „Scheduling heterogeneous real-time traffic
over fading wireless channels‟, in Proc. IEEE INFOCOM, San Diego, CA,
USA, pp. 1–9.
14. C. Joo, X. Lin, and N. B. Shroff, Aug 2009, „Understanding the capacity region
of the greedy maximal scheduling algorithm in multi hop wireless networks‟,
IEEE/ACM Trans. Netw., vol. 17, no. 4, pp. 1132–1145.
15. S. Weber, J. Andrews, X. Yang, and G. de Veciana, Aug 2007, „Transmission
capacity of wireless ad hoc networks with successive interference cancellation‟,
IEEE Transactions on Information Theory, vol. 53, pp. 2799-2814.
16. www.nmscommunications.com
45
ACKNOWLEDGEMENT
I would like to thank Mr.K.RAMESH (SUB-DIVISIONAL ENGINEER) from
RGMTTC (Rajiv Gandhi Memorial Telecom Training Centre) of BSNL (Bharat Sanchar
Nigam Limited) at Chennai, for his support in completion of this research project
successfully.
46
LIST OF PUBLICATIONS
P. Gokulapriya, R.Karthikeyan, “ANALYZING THE SIGNAL FLOW AND
RF PLANNING IN GSM NETWORK”,IEEE sponsored International
Conference on Innovations in Information Embedded and Communication
Systems [ICIIECS‟16], Karpagam College of Engineering, Coimbatore.