e.c umts project report

8/6/2019 E.C UMTS PROJECT REPORT

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CHAPTER 1

INTRODUCTION TO UMTS

1.1 Background and Requirements

There are three different generations as far as mobile communication is concerned. The first

generation, 1G, is the name for the analogue or semi analogue (analogue radio path, but digital

switching) mobile networks established after the mid-1980s, such as NMT (Nordic Mobile

Telephone) and AMPS (American Mobile Phone System). These networks offered basic

services for the users, and the emphasis was on speech and services related matters. 1G network

were mainly national efforts and very often they were specified after the networks were

established. Due to this, the 1G networks were incompatible with each other. Mobile

communication was considered some kind of curiosity, and it added value service on top of the

fixed networks in those times.

As the need for mobile communication increased, also the need for a more global mobile

communication system increased. The international specification bodies started to specify what

the second generation, 2G; mobile communication system should look like. The emphasis on 2G

is/was on compatibility and international transparency; the system should be a global one and the

users of the system should be able to access it basically anywhere the service exists. Due to some

political reasons, the concept of globalization did not succeed completely and there were some

2G systems available on the market. Out of these, the commercial success story is/was GSM

(Global System for Mobile communications) and its adaptations: GSM has clearly exceeded all

the expectations set, both technically and commercially.

The third generation, 3G, is expected to complete the globalization process of the mobile

communication. Again there are national interests involved. Also some difficulties can beforeseen. Several 3G solutions were standardized, such as UMTS (Universal Mobile

Telecommunications System), cdma2000, and UWC-136 (Universal Wireless Communication).

The 3G system UMTS is mostly be based on GSM technical solutions due to two reasons.

Firstly, the GSM as technology dominates the market, and secondly, investments made to GSM


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should be utilized as much as possible. Based on this, the specification bodies created a vision

about how mobile telecommunication will develop within the next decade.

Through this vision, some requirements for UMTS were short-listed as follows:

The system to be developed must be fully specified (like GSM). The specifications generated

should be valid world-wide.

The system must bring clear added value when comparing to the GSM in all aspects.

However, in the beginning phase(s) the system must be backward compatible at least with

GSM and ISDN.

Multimedia and all of its components must be supported throughout the system.

The radio access of the 3G must be generic.

The services for the end users must be independent: Radio access and the network

infrastructure must not limit the services to be generated. That is, the technology platform is

one issue and the services using the platform totally another issue.

1.2 Evolution of UMTS

3G has a completely new way to approach the term service: all the services offered should be

independent from the technology platform. This really opens the windows for free, 3rd party

service development. There will be several services, and the majority of those will be based on

the Internet in one form or another. In addition, imaging (picture transfer) and video phoning will

be interesting services.

If there is a possibility (as well as requirements and license), the operator may move to a

completely new level in service offering. This phase introduces new wideband radio accesstechnology, which, in the beginning, roughly equals the bit rates the EDGE concept is able to

provide. The new radio access requires new network elements in the radio network: RNC (Radio

Network Controller) and BS (Base Station) The BS is referred to as Node B in the 3GPP

specifications.


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The new radio access introduced in this phase is, however, utilizing the frequency spectrum

more efficiently; the data flow and its bit rate is not dependent on time slots any more. When the

radio access method was planned, the packet type of traffic was especially considered.

1.3 Advantages of UMTS

UMTS has several advantages, for example:

Efficient use of the radio frequency spectrum

Different technologies, which improve the spectrum usage, are easy to apply to CDMA. E.g. in

GSM, one physical channel is dedicated to one user for speech transmission. If discontinuous

transmission is applied, several timeslots of the physical channels are no used. These timeslots

cannot be used otherwise. In UMTS, the transmission of several mobile phones takes place on

the same frequency band at the same time. Therefore, each transmission imposes interference to

the transmissions of other mobile phones on the same carrier frequency band. UMTS supports

discontinuous transmission via the radio interface. Consequently, if mobile phones are silent,

when there is nothing to transmit, the interference level is reduced and therefore the radio

interface capacity increased. Another option allowed in UMTS is the multiplexing of packe t

switched traffic with circuit switched traffic. If there is no speech to transmit for a subscriber, the

silent times are used for packet switched traffic.

Limited frequency management

CDMA uses the same frequency in adjacent cells. There is no need for the FDMA/TDMA type

of frequency assignment that can sometimes be difficult. This is the main reason for increased

radio interface efficiency of WCDMA.

Low mobile station transmit power

With advanced receiver technologies, CDMA can improve the reception performance. The

required transmit power of a CDMA mobile phone can be reduced as compared to TDMA

systems. In the FDD mode, where bursty transmission is avoided, the peak power can be kept

low. Continuous transmission also avoids the electromagnetic emission problems caused by

pulsed transmission to, for example, hearing aids and hospital equipment.


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Uplink and downlink resource utilization independent

Different bit rates for uplink and downlink can be allocated to each user. CDMA thus supports

asymmetric communications such as TCP/IP access.

Wide variety of data rates

The wide bandwidth of WCDMA enables the provision of higher transmission rates.

Additionally, it provides low and high rate services in the same band.

Improvement of multipath resolution

The wide bandwidth of WCDMA makes it possible to resolve more multipath components than

in 2nd generation CDMA, by using a so-called RAKE receiver. This assists in lowering the

transmit power required and lowers interference power at the same time. The result is further

improved spectrum efficiency.

Statistical multiplexing advantage

The wideband carrier of the WCDMA system allows more channels/users in one carrier. The

statistical multiplexing effect also increase the frequency usage efficiency. This efficiency drops

in narrowband systems with fast data communications, because the number of the users on one

carrier is limited.

Increased standby time from higher rate control channels

The wideband carrier can enhance the transmission of the control channels. The MS only listens

to the control channels part of the time, thereby increasing the standby time.

1.4 Motives for using WCDMA in UMTS

The UMTS specifications include 3rd generation mobile services platforms. Being able to

deliver wideband multimedia services is going to require a higher performance standard than the

current wireless standards. UMTS will smooth the progress of new wireless wideband


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multimedia applications, while fully supporting both packet and circuit switched

communications (e.g. Internet and traditional landline telephone). From the outset, UMTS has

been designed for high-speed data services and Internet based packet data offering up to 2 Mbps

in stationary or office environments and up to 384 Kbps in wide area or mobile environments.

In UMTS Release 99, there are two WCDMA modes:

FDD mode

FDD stands for frequency division duplex. Two separate 5 MHz frequency bands are used one

for uplink transmission and another one for downlink transmission.

TDD mode

TDD stands for time division duplex. Hereby, one frequency band is used both for uplink and

downlink transmission. In the FDD mode a continuous transmission in one transmission

direction can take place. The TDD mode is more similar to GSM. Bursts are transmitted. The

reason for that is routed in the fact, that uplink and downlink transmission must be managed on

the same frequency bands at different times. The FDD mode is seen as a very good solution to

get coverage. The TDD mode is especially efficient, when there is asymmetric traffic. Because

of this and its bursty nature, it use is seen mainly in the pico and micro cell environment.

Both in the FDD and TDD mode, direct sequence CDMA is applied. The radio interface solution

is called Wideband CDMA (WCDMA), because 5 MHz carriers are used.

CONCLUSION:

The aim of this Chapter is to give the participant the introductory knowledge needed for

explaining how the UMTS network has evolved. Topics to be covered in this Chapter include

understanding the historic factors driving the system development and the evolution of the

mobile networks. Furthermore, the student should gain a basic understanding of the different

types of the air interface and list the key benefits of UMTS for the operator and the end user.


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CHAPTER 2

UMTS ARCHITECTURE

2.1 Introduction

A UMTS network can be visualized from different angles, such as from the point of view of the

user plane, control plane, or the function of each subsystem. In this module we will look at

UMTS from the latter angle, where the focus is on the different network elements within the

network.

The UMTS network architecture can be divided into three subsystems:

Radio Access Network,

Core Network including the network elements for service groups, and

Network Management Subsystem.

Each subsystem can be further divided into separate technologies. For example, the RAN (Radio

Access Network) is compromised of different air interface technologies, such as GERAN (GSM

EDGE Radio Access Network), UTRAN (UMTS Terrestrial Radio Access Network) and future

solutions such as WLAN, 1ExTREME and 4G.

The core network is today clearly divided into:

Circuit Switched (CS) domain and the

Packet Switched (PS) domain.

The network elements of the circuit switched domain are offering CS bearer services. They are

inherited from GSM: MSC, VLR and GMSC.

The packet switched domain is responsible to offer PS bearer services. Based on GPRS core

network elements, the PS bearer services are currently non-real time services. But standards are

on the way to enhance this infrastructure, so that also real-time services can be served via the PS


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domain transmission infrastructure. The CS and PS domains share some network elements.

These common CS and PS domain network elements are the HLR, AC, and EIR.

A set of service platforms was specified in GSM. These are now in an enhanced versionalso

available in UMTS. Network elements for service groups include CAMEL, text telephony,

location based services (LBS) network elements. As can be seen service provisioning is partly

located in the core network and contains all the service-enabling platforms that support the

multitude of 3G services that an operator can offer.

As shown in the figure below, the final subsystem must manage the whole network.


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Figure 2.1 UMTS Architecture

The 3G/UMTS specifications stipulated that the new air interface and system capabilities should

reuse the existing 2G systems, such as GSM and GPRS. Therefore, it is envisaged that operators

can quickly rollout network once the equipment is available. The standards dictate the

configuration of the open interfaces and the function of each subsystem; however, the

implementation is vendor/operator specific. This has led into much more modular network

architecture than we find in today's GSM networks. Nokia fully supports open interfaces. The


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network elements are designed to be modular and are built in the manner that the functions can

mature and evolve from new developments.

2.2 The UMTS core network elements

The UMTS Release 99 core network is rooted in GSM. In this section, the functionalities of the

network entities of the circuit switched and packet switched domain are outlaid, as well as those

which are common to the circuit and packet switched domain. The figure below shows the

specified network elements.

Figure 2.2 the UMTS Core Network

2.3 Circuit Switched Domain network entities

The term CS domain refers to a set of network elements offering CS type of connections for

the transfer of user data in combination with the related signalling. What is a CS type of

connection? The 3GPP refers to CS type ofconnections, when network resources are dedicated


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2.3.2 Gateway Mobile services Switching Centre (GMSC)

Similar to the MSC, the GMSC is an exchange, optimised for CS mobile related services. Being

an exchange, it owns the same exchange specific functions as an MSC. Its mobile

communication specific functions differ from the MSC. It is responsible for interrogation of

HLRs. The interrogation process supplies the GMSC with the Mobile Station Roaming Number

(MSRN). In case of a mobile terminating call, the MSRN is the telephone number of the MSC,

which is locally serving the mobile phone.

2.3.3 Visitor Location Register

A mobile phone is roaming in the supply area of an MSC, which is controlled by a Visitor

Location Register (VLR). When the MS enters the VLR supply area, it is automatically in a new

location area. The mobile station starts the location update/registration process. It gets registered

in the VLR, which also holds the information of the mobile phones current location. If the MS is

the first time in the supply area of the VLR, interaction with the HLR is required to get data

required for authentication as well as the subscription profile. If the location update request takes

place within a VLR supply area, an interaction with the HLR is only required, when the VLR has

no longer valid data to perform the authentication procedure. Given the subscriber profile in the

VLR, the VLR is also involved in the call set-up process. It holds the relevant information for

authorization. Data, which is stored in the VLR include the International Mobile Subscriber

Identity (IMSI), the Mobile Station International ISDN number (MSISDN), the Temporary

Mobile Station Identity (TMSI), if applicable, the last known location area (LAI), etc.

2.3.4 GSM evolutional notes on the core network

Part of the mobility management has been moved from the core network to the UTRAN,

compared to how it is implemented in GSM. As an example, handovers between RNCs are now

handled by the UTRAN, but in GSM the MSC is involved in handovers between BSCs.


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The security features are enhanced compared to GSM. This will mean new ciphering algorithms

and data integrity to support mutual authentication. The ciphering execution is moved to the

RNC of the UTRAN.

The speech handling (transcoding) function will be done by the UMTS core network. The speech

codec in will be AMR (Adaptive MultiRate). (In GSM, this task is taken care of by the

Transcoder, which is logically belonging to the BSS.)

A new platform for implementation and handling services has been standardized. This platform

is called CAMEL and will be available both for UMTS and GSM. In UMTS there is a new

interface between 3G-SGSN and SCP (Service Control Point), which is planned to enable

sending notifications about mobility management and session management procedures to the

CAMEL service environment. Also, charging operations can be performed via this interface, for

example to support prepaid subscriptions.

2.4 Network entities common to the circuit and packet switched Domain

The CS and PS domain entities share three network elements.

2.4.1 Home Location Register (HLR)

The HLR is a database, which holds the:

Semi-permanent subscriber profile and the

Temporary location information to support roaming.

The circuit switched network elements MSC and GMS are connected to the HLR via theinterfaces C and D, while the packet switched network elements SGSN and GGSN are connected

to it via the interfaces Gr and Gc. MSC and SGSN are serving the UE locally. They have to

interact with the HLR to retrieve information necessary for service provisioning. GMSC and

GGSN require location information to route mobile terminated call to the serving MSC and

SGSN.


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2.4.2 Authentication Centre (AuC)

The AuC is connected only with the HLR via the non-standardized interface H. The HLR

requests data for authentication and cipher setting from the AuC. The HLR can store this data,and makes it available to the VLR and SGSN on demand.

The data delivered from the AuC is used for:

Mutual authentication of the SIM-card (via IMSI) and the serving PLMN

Delivering a key to check the communication integrity over the radio path between the user

equipment and the VPLMN

Ciphering over the radio path between the user equipment and the RNC.

2.4.3 Equipment Identity Register (EIR)

This optional database is used to verify the International Mobile Equipment Identity (IMEI)

numbers. The EIR is organized in three lists:

Black list,

Grey list, and

White list

The black list holds IMEIs, which are forbidden in the PLMN. The grey list holds IMEIs under

supervision by law enforcement agencies, and the white list holds IMEIs, which are allowed to

access the PLMN

A mobile phone can be also classified as to be unknown in the EIR. The interface F connects the

EIR with the VLR, while the Gf interface links it with the SGSN.

2.5 Packet Switched Domain network entities

The term PS domain refers to a set of network elements offering PS type ofconnections for

the transfer of user data in combination with the related signalling. What is a PS type of


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connection? The 3GPP refers to PS type ofconnections, when user data is organized and

transferred in packets. Hereby, each packet can be routed independently.

In UMTS Release 99 the packet switched domain evolved from the GPRS core network

infrastructure. Four network entities are specified:

2.5.1 Serving GPRS Support Node (SGSN)

The SGSN constitutes an interface between the radio access network and the core network. It is

responsible to perform all necessary functions to handle packet switched services to and from the

mobile phone. Its tasks include:

Network Access Control

Authentication is one aspect of network access control. Hereby, the network is checking the

validity of the subscribers USIM and the USIM is checking the validity of the network

(SGSN). Only if both sides determine a successful authentication, network services can be

used.

Then the subscriber is requesting a service, the Authorization process makes sure, that the

subscriber is allowed to use the requested service. Please note, that the services, the

subscriber is authorized to use may depend on his location.

Other important tasks of network access control are the collection of Charging Data Records

(CDR) and Operator Determined Barring.

Mobility ManagementSimilar to the MSC, the SGSN is responsible for the mobility management, which includes

procedures like routing area update and paging.

Packet Routing and Transfer


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Its tasks include the classical packet switching aspects, such as relaying, routing, address

translation, encapsulation, and tunneling. In contrast to the 2G-SGSN, a 3G-SGSN is not

responsible for ciphering and user data compression.

2.5.2 Gateway GPRS Support Node (GGSN)

The GGSN constitutes the interface between the PLNM and external packet data networks

(PDN). Similar to the SGSN, it is responsible for the PS service provisioning. Its tasks include

Network Access Control

Two main network access control tasks are performed with a GGSN: It is responsible for

screening, i.e. the operator can determine, which type of packets is allowed to be transmitted

via a GGSN. Some manufacturers have outsourced this function into a separate firewall. The

GGSN is also responsible for charging data generation.

Mobility Management

The mobility management tasks include HLR inquiries in case of a mobile terminated call.

Packet Routing and Transfer

Packets have to be routed. The GGSN is responsible to relay them from one link to another,

determine the next route with the help of routing tables. The GTP protocol is used between

the GGSN and SGSN/RNC.

The user data is encapsulated to be transparently transmitted between the GGSN and RNC. This

is called tunneling.

2.5.3 Border Gateway Function (BG)

Roaming is possible for packet switched services. Hereby, user data and signalling information is

transmitted between the two PLMN via the interface Gp. The data has to pass border gateways

(BG) in each PLMN. The BG interfaces the PLMN and external, inter-PLMN backbone


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networks. Based on the roaming agreement between two operators, border gateways can perform

mutual authentication of each other before a secure connection is established between them and

data flows pass via them.

2.5.4 Charging Gateway Function (CGF)

Both SGSN and GGSN generate Charging Data Records (CDR). The CDRs routed via the CGF

to the billing system. The interface Ga is used between SGSN/GGSN and CGF. It is responsible

to:

Manage reliable CDRs

Act as intermediate storage for CDRs

Pre-processing of CDRs before forwarding them to the billing centre.

CONCLUSION:

The aim of this Chapter is to give the student the conceptual knowledge needed for explaining

the UMTS-network architecture. Topics to be covered in this module include visualizing the

whole network and identifying the elements of each subsystem. UMTS Architecture is same as

GSM Architecture with some modification of name and technology.


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CHAPTER3

INTRODUCTION TO UMTS HANDOVER MANAGEMENT

3.1 Introduction

The basic reason behind a handover is the same as in the GSM system; the Air interface

connection does not fulfill several criteria set for it and thus either the User Equipment or the

RAN initiate actions in order to improve the connection. In WCDMA, the handover with GSM-

like meaning is used in context of Circuit Switched calls. In the case of Packet Switched calls the

handovers are made when neither the network nor the UE has any packet transfer activity. The

handover types in WCDMA, however, are different from the ones present in the GSM systems.

There are two main types of handover in WCDMA these being soft and hard. Their difference is

that in the case of soft handover, the old radio link connection is maintained when the new

radio link connection is gained. The old radio link connection may or may not be dropped.

Thus, in case of soft handover, the UE may have several radio link connections active

simultaneously. In case of hard handover the old radio link connection is released before the

UE accesses the network through the new radio link connection.

These handover types have differences to each other but the common nominator for all of them

is handover criteria (why the handover should be performed) and the logic how the need for the

handover is investigated. Roughly, the criteria for the handover are based on the same items as in

GSM.

3.2 Handover Decision Making Mechanism

During the connection the UE continuously measures some items (blue text) concerning the

neighbouring cells and reports the status of these items to the network up to the RNC. These

items are measured from the neighbouring Cells PICHs. The RNC checks whether the values

indicated in the measurement reports trigger any criteria set. If they trigger, the new BTS is

added to the Active Set.


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Figure 3.1 Handover Decision Making Mechanism

Hand Over Failure reasons:

Low signal strength or bad quality on target cell.

Hardware problems in target cell

Interference in target cell

What to do when handover failure happen?

Find out who was serving cell

Find out who was target cell from layer 3 message ( HO Command )

It can happen UL or DL related problem in target cell, which can be further

analyze by using Layer 3 signaling


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3.3 Soft Handover

Figure 3.2 WCDMA Soft HandoverPrinciple

Soft Handover is performed between two Cells belonging to different BSs but not necessarily tothe same RNC. The source and target Cell of the soft handover have the same frequency. In case

of a Circuit Switched call the terminal is actually performing Soft Handovers all the time if the

radio network environment has small cells.

3.4 Softer Handover

Figure 3.3 WCDMA Softer HandoverPrinciple

In Softer Handover the BS transmits through one sector but receives from both of the sectors. In

this case the UE has active uplink radio connections with the network through two cells

populating the same BS.


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3.5 Hard / Inter-frequency Handover

Figure 3.4 WCDMA Hard HandoverPrinciple

The WCDMA Hard Handover is a GSM- like Handover made between two WCDMA

frequencies. In case of hard handover, the connection through the old cell is cleared and the

connection with the radio network continues through the new cell. Hard Handover is not

recommended unless there is a desperate need: this Handover type increases interference easily.

3.6 Hard / Inter-frequency Handover

Figure 3.5 Hard / Intra-frequency Handover

This type of handover is performed if the Iur interface is not available. For example, Between the

RNCs coming from two manufacturers.


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3.7 Inter - System Handover

Figure 3.6 WCDMA Inter -System Handover

Because of the possible co-existence of the different radio accesses in the 3G network, the UE

should be able to fluently change the radio access technology when required. In order to present

this kind of situation, the 3G Specifications identify the combination of WCDMA and GSM as

one source for InterSystem Handovers. This has already been taken into account in WCDMA

frame structures.

The possibility to perform an Inter-System Handover is enabled in the WCDMA by a special

functioning mode, Slotted Mode. When the UE uses Uu interface in Slotted Mode, the contents

of the Uu interface frame is compressed a bit in order to open a time window through which

the UE is able to peek and decode the GSM BCCH information.

Additionally, both the WCDMA RAN and GSM BSS must be able to send each others identity

information on the BCCH and BCH channels so that the UE is able to perform the decoding

properly.


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CONCLUSION:

The aim of this Chapter is to give the student the conceptual knowledge needed for explaining

how traffic management is visualized in a UMTS network. Topics to be covered in this Chapter

include understanding the different types of Hand over occur during the call. In GSM all

handover is called Hard Handover. While in UMTS Handover is defined based on the site and

the sector of the same site and different site.


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CHAPTER 4

RF AND LOS SURVEY

4.1 RF SURVEY PROCEDURE:

Collect data from office and ask the coordinator about Type of Survey (e.g. in filler / New

Town / Other).

Collect Site details e.g. Site Name, Taluka & District etc., Site Coordinates (Lat/Long) &

Far End details.

Check your complete Survey Kit

1. GPS (Global Positioning System)

2. Binocular

3. Compass

4. Digital Camera with Data cable

5. Measurement Tape

6. Blank Survey Form

4.1.1 NEW TOWN SURVEY:

Feed the coordinates of the Site in your GPS and click GOTO option. It will show the

bearing and distance of your site from your current position.

The given coordinate may not be correct, find the correct town by the discussion with

local persons.

Now after reaching the Site follow these steps-

1. Take the hotspots of whole town (approximately 30-35 depending upon officials

requirement) as well as all main roads connected to that Town(4-5 each road).


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2. Look for the 3 Options feasible from RF & LOS point of view.

3. In case of unavailability of all the options in the centre shift the options but take

only those from where all sectors have proper clutter (e.g. residence /shops /roads

etc.).

4. Write down the details of each option.

Choose the highest building or Water Tank to take photos (12 photos at 30 degree each

starting from 0-330), normal and zoom photographs of all the far ends.

Draw the layout of the Town showing all the options, major landmarks (GP/Shopping

centre /Temple /Masque /Bank /School /Main chowk) & roads.

Decide the GSM Antenna height.

4.1.2 ANTENNA RADIATION HEIGHT & TILT:

Highway/Railway Coverage cells Antenna height should be at 40m with 2 degree

Mechanical tilt.

Single site town facing cells Antenna Height should be 30m with 2 degree Mechanical

tilt.

Existing town, coverage filling sites cells Antenna height should be at 21m with 4

degree Mechanical Tilt.

Existing town, Capacity sites cells Antenna height should be at 21 meters or less than

that depends on surrounding sites foot print and carrying traffic loading.( Tilt will be 4

degree Mechanical )

In short, three height categories 21m, 30m and 40m depends of type of cells and itsobjective.


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4.1.3 ANTENNA TYPE:

Highway and Railway Cell: 30 degree H-Plane, 7.5 to 10 degree V-Plan and 21 dBi

Gain without Electric tilt. (if this type of antenna not available then 65 H, 8 V and 18 dBi

Antenna cab be proposed, this is best for highway also as may be parallel to

road/highway some small towns or tourist places can be cover ).

Single Town/ Coverage infill/ Capacity Cell: 64 degree H-Plane, 7.5 to 10 degree V-

Plan and 18 dBi Gain without Electric tilt.

4.1.4 IN-FILLER (CITY) SITE:

Reach at the given coordinate position and choose the Optimal Location of Sites. This

may depend on so many factors likes:

Target area clutter type

Size of Target area

Requirement of Indoor coverage penetration

Hot spots locations

Availability of suitable land or buildings

Structure suitability of building

Major entry and exist roads & railways

Specific some event locations like festive or tourist place

Future development of target town

Surrounding existing network foot print and their traffic handing capacity

Signal Propagation behavior depends on typical clutter and terrain type

After deciding the suitable location note down the following details:


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Options coordinate.

Orientations of all the 3 sectors.

Terrace layout and place, suitable to build the Tower, also check for the space for BTS.

Details of each option (as in New Town).

Photographs (as in New Town).

Transmission part is also same as in New Town.

Show the sector orientations in layout by Arrow.

Here the tower height will be different from New Town.

You can propose RTT, Pole, Parapet or Wall mount, depending upon the clutter type and

building heights surrounding that area.

Calculation of Total Tower height must be AGL (Above Ground Level).

AGL height = Building height + Tower height.

One Floor of the building is considered as 3m (4m for ground floor in case of commercial

building)

4.2 TRANSMISSION (LOS) SURVEY:

Select the ROUTE option in GPS and feed the coordinates of Near End & Far End and

Activate the route.

Start following the LOS line shown on GPS.

Take the route data (Obstruction height/Tree/Building/Chimney/Other Tower/Water

Tank etc.) at every 500m. It also depends upon the terrain, if there is high variation in

terrain or obstruction height then takes the detail of that point also even if it is very near

to your previous point taken.


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After reaching your Far End check for the Existing Tower height and spaces for

mounting the MW towards the Near End.

Give only minimum height both sides but take care that the first Fresonal Zone must be

very clear.

If your Far End is visible from Near End then you need not to follow all the above steps,

check only the last step.

4.2.1 TOWER HEIGHT:

If site is GBT then tower height should be 40m or subject to Transmission requirement

In case of roof top, in existing town for coverage motivated sites should keep Antenna

radiation center at 21m and capacity driven sites can be at 21 or less then that depends on

traffic off loading target to minimize over reaching

4.2.2 MW HEIGHT CALCULATION:

Microwave height depends upon Fresonal zone, through which the waves travel carrying

the voice and data signals. This zone must not be disturbed while deciding MW height.

Fresonal zone=N*17.3(d1*d2/Fd)

Where N=no of Fresonal zones

F=frequency used by the operator

(e.g.7Ghz, 15 GHz, 18 GHz or 23 GHz)

d=distance between Near End and Far End

d1=distance from near end to maximum obstructing object

d2=d-d1


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Fresonal Zone:

Figure 4.1 Fresonal Zone

4.2.3 TYPES OF TOWER:

GBT (Ground Based Tower)

Height- 30m/ 40m/ 50m/ 60m/ 70m/ 80m. RTT (Roof Top Tower)

Height- 9m/ 12m/ 15m/ 18m/ 21m/ 24m.

RTP (Roof Top Pole)

Height- 3m/ 4.5m/ 6m.

Parapet- GSM antenna will be mounted on parapet.

Wall mount- GSM antenna will be mounted on Building Wall.


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CONCLUSION:

The aim of this Chapter is Using RF Survey; know the actual idea about new site set up, know

the requirement of the site set up in particular area and also know whether existing site and its

requirement in particular location. Using LOS Survey; know that from which far end site the

near end site gets MW link.


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CHAPTER 5

PHYSICAL AUDIT PROCEDURE

5.1IntroductionThe objective of this Chapter is to provide the good understanding of types of survey and there

detail description so that the customer objective can be fulfilled. This guideline can be changed

based on customer concern to meet site objective.

5.1.1 Why Physical audit?

To check actual lat long where site exist it may be differ from planned lat long.

To check radiation height of antenna.

To check orientation and tilt of antenna.

To check Installed BTS type.

To check Tower Type.

To check antenna beam is blocked or not.

To check Feeder cable is connected to antenna / BTS.

It is always better practice to do Physical Audit before starting SCFT. Physical

Audit is a part of SCFT for this project.

5.1.2 Equipment Needs:

1. Hand GPS

2. Magnetic Compass

3. Measure Tape

4. Camera / Mobile phone with minimum 2.0 MP camera


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5.1.3 Antenna Type

Single Band Antenna Dual Band Antenna Tri Band Antenna

Figure 5.1 Antenna type

5.1.4 BTS Classification (NODE B):

Type 1:1. Classical : Not connected with mast or pole. BTS is connected with

Antenna using feeder wire.

2. RRH : Connected with pole or mast. There is a jumper wire whichConnect antenna and BTS.

Type 2:

1. Outdoor case OR shelter : In this BTS is in case(grill) and we can see it2. Indoor : In this we cant see BTS. It is packed AC

Connection is also provided

5.1.5 Photos need to be taken:

Building Photo

BTS Photo

Antenna photo with Tilt for all sectors

Antenna photo with mast for all sectors

Mast Photo (Site photo)

Miscellaneous photo(if antenna got blocked by some obstacles )


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Figure 5.2 Building Photo Figure 5.3 BTS Photo

Antenna Photo with Tilt for all sectors :

Fig5.4 Sec1 with Tilt Fig5.5 Sec2 with Tilt Fig5.6 Sec3 with Tilt

Antenna photo with mast for all sectors :

Figure 5.7 Sec1 Figure 5.8 Sec2 Figure 5.9 Sec3


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Figure 5.10 Mast photo ( 6M RTP )

5.2 What is difference between Electrical tilt and Mechanical tilt?

In urban area mostly now a day Electrical tilt used, and reason is when you give tilt

using E tilt , font and back lobe both get tilted which reduce interference in network, andalso shape of Main lobe doesnt get change only size become small.

In case of Mechanical tilt, if you give tilt then font lobe will get tilted and back lobe will

up tilted which might create interference to other cells, and also shape of main lobe will

get wide which again create interference in network so thats why such antenna can be

use in rural or highway kind o sites where intra site distance is high and those kind of

area are not much sensitive to interference

CONCLUSION:

The aim of this Chapter is to check the equipment installed at site is working properly or not.

And Site is Set up at given location with given orientation or not. Also check the types of

equipment installed due to what reason.


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CHAPTER 6

DRIVE TEST

6.1 DRIVE TEST USING TEMS:

Drive Test is useful for Site Survey of particular Site. Using Drive Test we know about how

much distance from site the network coverage is coming, hand off between sector of same site is

occur or not, clarity of video call & voice call, Data Speed near site etc. For drive Test we use

TEMS software. This software provides flexibility for Site Survey.

Figure 6.1 Drive Test in Car


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6.1.1Drive Test Equipments

1. TEMS Handset (complete with Charger, Headset, Data Cable) and USB Hub

2. Laptop (installed TEMS Investigation) and Adapter

3. GPS (Ext Antenna and Data Cable)

4. ATEN (Serial to USB)

5. Scanner for WCDMA (Ext Antenna GPS and RF, Data Cable)

6. Inverter and Terminal

7. Battery and Charger

Figure 6.2 Position of that equipment in the car
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Figure 6.3 Flow chart of Drive Test


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6.1.2 What is the motivation behind GSM Air Interface drive testing?

GSM Drive testing is traditional and best way to verify network performance

For New Sites or Existing sites.

Drive testing can be asked for various objectives like

o Coverage verification

o New site Performance Verification and Field optimization

o Network Problem trouble shooting like Drop calls, Handover failure, Poor

Coverage patches, Poor RX Quality patches, etc

o Benchmarking Drive test to find out Coverage and Quality comparison against

competitors networks

6.1.3 How to do Coverage verification Drive test?

Best way to do it by putting TEMS Phone in Idle mode and drive across targeted routes

In Idle mode, MS will measure BCCH TRXs Time slot 0 and TS 0 transmit always full

power which is consider as real foot print of BCCH ( which is call as Cell foot print ) and

such RX LEVEL is RX LEVEL Full because TIMESTOL 0 doesnt have DTX and POWER

CONTROL

But when you do Dedicate mode Drive testing then TCH TRX has most of the time DTX ON

and POWER Control too so that RX LEVEL Measurement is RX LEVEL SUB which is not

genuine Cell foot print.

o DTX: Discontinues Transmission Mode

6.1.4What is the information need to be collected and carry before to

Start any Drive testing work?

We go for Drive test, we need to collect all require information for site or group of sites(

cluster ) like

o Site Master Database, which has Antenna parameters like Azimuth, antenna tilts,

Antenna Type, Height, Tilt, Azimuth( Physical Verification and Optimization)

Digital Maps for DT


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Frequency Plan for Sites including BCCH and Hopping ( Frequency

Optimization and Interference detection)

Neighbor List so we can compare who is missing for addition or unnecessary

defined for removal ( Neighbor Optimization)

Complete tools like DT Kits, Camera, Compass, etc

Rigger with require tool for Physical optimization changes

If any major complaints or input from RF Optimization team or DT coordinators

Drive test desired route if any specific

Drive test Cell file for reference so when we do Drive test at least we can co

related what is happening and which cell is serving

6.1.5 Key features of TEMS

Supports simultaneous use of two GSM phones

Intuitive user interface

Flexible mounting solution adjusts to most any Vehicle.

Integrated GPSno external boxes required

Freeze functionality to pause the display while collection continues.

Removable compact storage for log files

Quick and easy presentation views, including GPRS information

Auto-dialing scripting from the display

Audio alarms for safety during drive tests

Auto On/Auto Off controlled by vehicle ignition


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6.2 SITE SURVEY:

TEMS software is use for Site Survey. There are various versions of TEMS. Now a day

version 10.0.5 is mostly used.

Software like TOMOGRAPH, NETBIN, ZYXCL, DRAGNET etc. are available for Site

Survey.

6.2.1 What need to be check when you reach to any new sites for DriveTest?

When we reach to site, 1st thing need to be done is Sites Antenna physical parameter

verification

If any antenna parameter is wrongly implemented like Azimuth or Tilt then there is no

use of doing drive test

Once Antenna parameter check and all are as per require or planed, then we

can start call testing , handover testing and area coverage verification

Drive testing can be done with various testing scenario but widely done as per below:

o Call testing cell wise to understand performance of cell and each TRX

o Inter cell between same site handover testing

o Inter cell between different sites for handover testing

o Coverage verification drive till you get -95 dBm RX Level Full in idle

o mode

o Frequency Plan check BCCH and Hopping

o C/I Verification

o RX Quality Sub in Dedicated mode

During Drive test some time you might face, Call drop , Handover fail, Block call, etc.

and in thats case we need to do some analysis and you have find out who is service cellwhen we had such problem

6.2.2 What value of C/I( Co Ch ) and C/A (Adj ch) interference is

Desired in network?

As per the GSM C/I => 9 dB and C/A => -9 dB


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5. WCDMA service/Active set.

6. Events.

7. Map info.

8. WCDMA Rel-99.

6.2.5 Drive Test Activities:

1. Anti clockwise & Clockwise drive around site.

2. MOC (Mobile Originate Call).

3. MTC (Mobile Terminate Call).

4. SMS from MS1 to MS2.

5. Voice call from MS1 to MS2.

6. Video call from MS1 to MS2.

7. FTP test.

8. Data with call.

9. Hand off Measurement.

6.2.6Practical issues Found During Drive Test:

During Drive Test of Site Number GNR-011 located in Gandhinagar and GBT SEC -

10CW located in Gandhidham, there is a problem of cable swap between Sector-x and

Sector-y. So there is coverage of Sector-x in Sector-y and coverage of Sector-y in Sector-

x. We are able to find this problem with the help of the TEMS software.

During Drive Test of Site Number GNR-036 located in Gandhinagar, call drop occurred

when user moving from one sector to another sector of same site. So that problem


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indicates that between 3 sectors hand off is not define. So hand off must define between

sectors for solving the problem of call drop.

Another problem of at this site is that when call from MS1 to MS2 there is a message

CALL ATTEMPT RETRY due to poor coverage of 3G in all sectors.

Also problem is that from GNR-036 site to GNR- 034 site hand off was occur but in

reverse manner hand off is not occur. So that means bi-directional hand off for GNR- 034

is not defined.

For one site POG-001 we increased mechanical tilt for reducing overshoot problem.

One very important concept of hard hand off we experienced, this is also known as

IRAT. In this problem we experienced that call hand over from 3G to 2G.

CONCLUSION:

The motive of this Chapter is useful for checking network coverage at site. Also Using Drive

Test one can know about the Internet speed, Types of handover is occur at the particular site ornot, Message quality etc. Also Using Drive Test one can get the idea about how much tilt is

given to the antenna based on user requirement.


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REFERENCES

1.Nokia systra manual

2.Nokia systra 3G manual3.Teleysia Training manual

4. Introduction to UMTS training manual

5.RF and TX survey manual

6.Physical audit manual

7.3G Drive Test Learning manual


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APPENDIX

Appendix I Abbreviations

3G 3rd generation

AMR Adaptive MultiRate

AUC Authentication Centre

ADCE Adjacency

AGCH Access Grant Channel

ARFCN

AIS

Absolute Radio Frequency Channel Number

Alarm Indication Signal

BC Broadcast Channel

BCCH Broadcast Control Channel

BCF Base Control Function

BCH Broadcast Channel

BCSU BSC Signaling Unit

BER Bit Error Rate

BGW Billing Gateway

BS Base Station

BSC Base Station Controller

BSIC Base Transceiver Station Identity Code

BSS Base Station System

BTS Base Transceiver Station

CBCH Cell Broadcast Channel (Not a standard logical channel)

CS

CDMA

Circuit Switched

Code Division Multiple AccessCI Cell Identity

CSPDN Circuit Switched Public Data Networks

CC Country Code, Call Control

CCH Common control channels


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DT Drive Test

DCCH Dedicated channels

DCN Data Communication Network

DCS Digital Cellular System

EIR Equipment Identity Register

FDMA Frequency Division Multiple Access

FACCH Fast associated control channel

FACCH/F Full rate Fast Associated Control Channel

FACCH/H Half rate Fast Associated Control Channel

FCCH Frequency Control Channel

GBT Ground Based Tower

GPS Global Positioning System

GPRS General Packet Radio Service

GSA GSM System Area

GSM Global System for Mobile Communication

GSM PLMN GSM Public Land Mobile Network

HLR Home Location Register

HO Handover

HSN Hopping Sequence Number

IDN Integrated Digital Networks

IMEI International Mobile Equipment Identity

IMSI International Mobile Subscriber Identity

IP Internet Protocol

ISDN Integrated Services Digital Network

LAC Location Area Code

LAN Local Area Network

MCC Mobile Country Code (of the visited country)

MNC Mobile Network Code (of the serving PLMN)

MOC Mobile Originated Call

MNP Mobile Number Portability

MS Mobile Station


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MSC Mobile switching center

MSIN Mobile Subscriber Identification Number

MSRN Mobile Station Roaming Number

MTC Mobile Terminated Call

NMS Network Management Subsystem

NSS Network and Switching Subsystem

O&M Operation and Maintenance

OMC Operation and Maintenance Centre

OMU Operation and Maintenance Unit

OSI Open System Interconnection

OSS Operation and Support System

PCH Paging channel

PCM Pulse Code Modulation

PDN Public Data Networks

PLMN Public Land Mobile Network

PSPDN Packet Switched Public Data Network

PSTN Public Switched Telephone Network

QoS Quality of Service

RACH Random access channel

RAND Random Number (authentication)

RBS Radio Base Station

RF Radio Frequency

SDCCH Stand-alone ded icated control channel

SGSN The Serving GPRS Support Node

SIM Subscriber Identity Module

SMS Short Message Service

SMS-GMSC Short Message Service, Gateway MSC

SMS-IWMSC Short Message Service Inter Working MSC

SN Subscriber Number

SACCH Slow associated control channel

TC Transcoder


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TCH Traffic control channels

TDMA Time Division Multiple Access

TEI Terminal Equipment Identity

TMN Telecommunications Management Network

TMSI Temporary Mobile Subscriber Identity

TRC Transcoder Controller

TRX Transceiver

TSL Time Slot

VLR Visitor Location Register

e.c umts project report

Documents