Docstoc

GSM at Nokia Siemens Networks

Document Sample
GSM at Nokia Siemens Networks Powered By Docstoc
					THAPAR UNIVERSITY

Presentation on Project Semester Training at

NOKIA SIEMENS NETWORKS

Company profile:

Nokia Siemens Networks was formed by the merger of telecom giants Nokia Networks and Siemens to form the world’s largest telecommunication company in April 2007. In India, with the head office at Gurgaon (haryana) Nokia handles the accounts of Bharti Airtel,Vodafone,BSNL,IDEA and other operators. The services include network planning ,maintenance ,optimization as well as providing necessary hardware equipments. It has now become the leading service provider ahead of competitors like Ericsson ,Motorola ,Nortel Networks .

Various Phases of Training in Planning & Optimization Deppt Phase One: Nokia Systra :Nokia’s training material for the basic study of GSM Phase Two:

RF planning :Nokia Net Act Planner, Vodafone Maharashtra circle planning.
Phase Three: MapInfo tool: Learning Map basic language, Map basic application tool for analysis of OMC Reports of Nokia, Transmission Department’s map basic application tool for MW links. Analysis of reports of West Bengal Circle. MW links reports of Airtel Gujarat circle.

Overview of the GSM Interfaces For the connection of the different nodes in the GSM network, different interfaces are defined in the GSM specifications. · Air interface The Air Interface is the interface between the BTS (Base Transceiver Station) and the MS (Mobile Station). The air interface is required for supporting: - Universal use of any compatible mobile station in a GSM network - A maximum spectral efficiency · Abis-interface The Abis-interface is the interface between the BSC (Base Station Controller) and the BTS. The interface comprises traffic and control channels. Functions implemented at the Abis-interface are: - Voice-data traffic exchange - Signaling exchange between the BSC and the BTS - Transporting synchronization information from the BSC to the BTS · A-interface The A-interface is the interface between the BSC and the MSC.

Phase 2:
Maharashtra circle planning for Vodafone Nokia Net Act Planner Fundamentals of Network Planning

Nokia Net Act Planner::

Nokia Net Act is Nokia’s software for planning radio network in 2g and UMTS(3g).
The snapshots to describe the basic functions of it and the use of it to plan the radio network in Maharashtra are as follows

Clutter:

As the input to the Net Act we entered the clutter values. These values provide approximated attenuation 1.business district 2.dense urban 3.dense suburban 4.mean urban 5.low urban 6.mean suburban 7.low suburban 8.forest 9.rural 10.Water

clutter

building height

building separation

resulting loss

dense urban

25m

20m

38 dB

mean urban

15m

20m

33 dB

low urban

15m

50m

29 dB

dense suburban

25m

50m

34 dB

mean suburban

15m

100m

26 dB

low suburban

6m

100m

15 dB

business district

90m

20m

50 dB

With the help of a particular kind of propagation model which takes in account the resulting attenuation, diffraction losses ,signal reflection etc we can predict the signal power level up to a certain distance.

In Nokia Net Act, for Maharashtra project we used the Standard Macrocell model.

Antenna Eirp =56dbm Propagation Model =Standard Macro cell Antenna Type = GSM(900) 74232 ,74234,74122.

Depending upon the customer requirement we cover the region according to the Best Server Power Levels as shown on the left.

Through these plots we get a fair idea of the approximate locations of the sites to be set up. This is followed by the Drive Test which gives us a better way to decide the exact positions for site to be developed. Lets say what is we predicted a site to be developed as on a position x ,but during the Drive tests it comes out that the site region belongs to a landlord who is not willing to give his land for site. Then the whole process for that particular region is repeated and new locations for sites are given.

In this way overall 13,000 sites were predicted by me for Maharashtra circle.

Phase 3
1.Mapbasic Application Tool for Analysis of OMC Reports of Nokia. MapInfo is a software used for many purposes which evolve sites with available latitude and longitudes. These sites with other databases in tabular form can be used to graphically show them on map. To create various utilities for GSM sites I had to learn Map basic ,which is a kind of scripting language ,very much alike Visual basic and Basic . Need for the tool ??

The OMC Reports of Nokia such as Report 232,Report 153 Report 166 etc are generated in text format. Now for circles such as West Bengal or Maharashtra where there may no of sites as much as 30,000 to 50,000 it is not possible to detect the usual errors or performance of sites due to unread ability of text files.
So we were asked to make a tool which could read the format to every report and then depending upon the threshold values given by the user performance of sites can be analysed.

Report 153:
This report gives a list of adjacencies for the HO type you have selected, either all or only those between different bands, and both the HO failure ratio and the number of HO attempts that equal or exceed the given thresholds. Source Target ****** ****** SEGMENT NAME (ID) SEGMENT NAME (ID) BCF NAME HO=> HO=> HO=> <=HO <=HO <=HO Target BCF NAME BSC NAME **** **** **** **** **** **** ****** BSC NAME BAND Att Blck Fail Fail Blck Att LAC BAND BCF TYPE (%) (%) (%) (%) CI BCF TYPE ------------------ ------- ---- ---- ---- ---- ------ ------ -------------------NDAMODARLYST2 (294 21 0 100 0 0 0 8046 EADRADRA031 (65) ) 51101 ADRA03_IDU DAMORLYSTN_ODU BSC46ADR BSC20ASL GSM900 GSM900 UltraSite UltraSite

Report :154
The distribution (%) of HO attempts by causes are shown for each cell: UL qua /c4023 UL quality UL lev /c4024 UL level DL qua /c4025 Downlink quality DL lev /c4026 Downlink level Dist high /c4027 Distance exceeds limit MSC /c4028 MSC invocation (traffic reason) UL itf /c4029 Uplink interference DL itf /c4030 Downlink interference Umbr /c4031 Umbrella Pbgt /c4032 Power Budget OMC /c4033 Operation and maintenance (forced by user) DR /c4079 Directed retry PrEm /c4086 Pre-emption (S3) RFD /c4087 Rapid field drop (S4) Dist low /c4088 Low distance (S4) CI Bad /c4089 Bad C/I ratio (S4) CI Good /c4090 Good C/I ratio (S4) Slow Mov MS /c4091 Slow moving MS (S5) MS spee slow /c4105 Slow speed of MS (S6) MS spee high /c4106 High speed of MS (S6) CTC /c4099 HO to change Aif circuit type (S5) ERFD /c4111 Enhanced Rapid field drop (S7) TRHO /c4035 BSC controlled TRHO (S8) DADL /c4129 DADLB (S8) GPRS /c4130 HO to enable GPRS territory upgrade (S9) HSCSD /c4141 Intracell HO attempt for a single slot call . for enabling upgrade for an HSCSD call (S10) Rx Bad /c4109 Bad Rx level (S7) Rx Good /c4110 Good Rx level Dir Acc /c4128 Direct access attempts (S7) Inter band due lev /c4163 TCH-TCH HO from non-BCCH due to weak downlink (S10.05) ISHO /c4180 TCH-TCH HO from GSM to WCDMA RAN (S11) Intersys dir acc /c4181 SDCCH-TCH from GSM to WCDMA RAN due to direct access (S11) AMR FR-HR /c4142 HO attempts from AMR FR to AMR HR (S10) AMR HR-FR /c4143 HO attempts from aMR HR to AMR FR (S10) Inter band SDCCH /c4133 Attempts to perform based on duration of an SDCCH reservation (S10) Inter band TCH /c4135 Attempts to perform a TCH-TCH HO between BTS on different freq (S10) Inter BTS type SDCCH /c4137 Attempts to perform SDCCH to SDCCH based on duration of an SDCCH (S10) Inter BTS type TCH /c4139 Attempts to perform TCH to TCH HO between different BTS types (S10) Nbr of HO att /ho_13h Number of HO attempts

Report 150: This report shows HO failure rates for all cells sorted out by failure rate. Tot HO Fail

Segment name Type Att Fail Blck NotA Drop Other BSC (SEG id) % % % % % % ----------------- ------------------------------------------------- -----NMALMALAYPR1 MSC i: 0 0.0 0.0 -- 0.0 0.0 98.2 BSC43GBR(425) MSC o: 0 0.0 0.0 0.0 0.0 0.0 BSC i: 930 94.9 0.0 -- 1.3 93.6 BSC o: 32 1.4 0.4 0.0 0.0 1.0 Cell : 50 61.0 0.0 0.0 0.1 60.9

Tot

Report 163
TO CALCULATE CELLS HAVING HIGH TCH DROP CALL RATIO.

Bids ***** Rf Tr Abis Aif Call Re-es (%) (%) (%) (%) DR ***** ***** *** *** *** Segment BTS FCS SDCCH call call call call BSC (SEG id) count T-T HO TCH old old old old NFATPURR3 BSC30BLA (56) 1 288 0 549 0 0 113.9 0.0 17.7 0.0 0 8.3 0.0 0.0 0.0 0.0

(%) **** Lapd BTS BCSU 0.0 0.0

(%) *** Drop User Ratio Cnfg (%) Act dcr_31 0.0 140.3 0.3 0.0

Report 232:
In this report the cells are listed with the distance range. The share in range (%) parameter is used to study the working of a BTS. For example if a BTS power is designed up to a range of 10 kms but maximum (more than 95%) calls are made from range within 1.1 kms then it can be reduced . Distance upper min max TRX EXT range Freq of range power power type (km) (km) reports (%) (dBm) (dBm) ------ ---- -------- -------- ------- ------ ------ -----normal 0 0.55 740518 54.94 5 33 normal 0 1.10 102512 7.61 5 33 normal 0 2.20 55418 4.11 21 33 normal 0 3.30 32218 2.39 23 33 normal 0 4.40 279124 20.71 23 33 normal 0 6.60 128196 9.51 25 33 normal 0 8.80 7012 0.52 33 33 normal 0 11.00 2938 0.22 33 33 normal 0 17.60 0 0.00 -- -- -normal 0 34.65 0 0.00 -- -- --

Report 196:
This report is to check the quality class of the signal received by MS . The calls are sampled every 480 ms for the quality class. Quality class info is used on Abis but BSC converts the quality classes into BER % figures using the default values. (Power control measurement shows BER figures).

Class BER
qua 0 (BER < 0.2%) qua 1 (BER 0.2 - 0.4%) qua 2 (BER 0.4 - 0.8%) qua 3 (BER 0.8 - 1.6%) qua 4 (BER 1.6 - 3.2%) qua 5 (BER 3.2 - 6.4%) qua 6 (BER 6.4 - 12.8%) qua 7 (BER >12.8%) The rule of thumb is that in quality classes 0-5 the MS user does not yet feel that the quality is bad.

Report 208
This report counts the power loss balance between UL and DL for each TRX of each cell of the selected area
The UL Power loss is calculated as (MS power –UL signal strength as measured by the BTS) The DL power loss is calculated as (BTS power –combiner loss –DL signal strength reported by the MS.) Now the factor DL-UL power loss factor is more important as it shows error is from either side. Report format:

DL loss factors UL loss factors *************** *************** BCF BCFtype BS power DL MS power BTS BTS id combiner loss path BSC TRX id DL sig str loss UL sig str -------------- ---------- --------------- ------ --------------- ------ ------SRIPUR_IDU UltraSite 44.7 120.7 30.8 NSRISRIPUR1 4 -5.2 BSC20ASL 1 -81.2 -95.0

UL path loss 125.9

Balance ****** DL-UL Delta -5.2 0.4

PROJECT FOR TRANSMISSION DEPPT ::MW LINKS
Due to the immense usability of the Map Basic application developed by us .The transmission department gave us a project to develop a tool for studying the status of MW links between sites. MW links are made between various sites so as to make a communication between various BTS and the BSC. This was earlier also done through optical links but every time new site is installed its not possible to establish links using optical fibers. MW links work in a band of 15 GHz frequency.

Customers (Telecom operators ) like Bharti ,Vodafone etc get only a small band to operate in this MW frequency range. Thus maintaining these links is an important issue. Any link having used capacity less than 30 % is considered not useful .Or the factors such as fade margin are also useful parameters to maintain communication between the BTS and BSC.



THANK YOU


				
DOCUMENT INFO
Shared By:
Stats:
views:4683
posted:10/19/2009
language:English
pages:54
Description: knowledge about how GSM works and working of map info software and project in map basic language