Ericsson RAN OAM

O&M Handbook for Ericsson RAN

O&M Handbook for Ericsson RAN

Released by BSNL

O&M Handbook for Ericsson RAN

O&M Handbook for CMTS Networks

on

Ericsson Technologies

(BSNL Internal Circulation Only)

Message

Anupam Shrivastava

Chairman and Managing Director BSNL Board

I am happy to note that Consumer Mobility vertical has taken an initiative to provide a comprehensive, OEM technology wise, ‘Operations & Maintenance Handbook’ for routine operation and maintenance. In this series, this handbook on Ericsson will be extremely beneficial for use by our Technicians and Engineers in 17 Circles of North and East Zones.

I feel that such a Ready compilation of day to day O & M activities, being followed in the 17 circles, at one place will go a long way in helping our field units to learn from good practices being followed in other circles.

I congratulate Director (CM) Shri R. K. Mittal and his team for this great initiative and efforts. I am looking forward for release of such O&M Handbooks for other technologies.

Message

Director (CM) BSNL Board

I am very glad to see that the Handbook on CMTS Operation and Maintenance for Ericsson technology has been made first time in BSNL. Availability of this comprehensive Handbook with the field engineers and technicians for carrying out day to day operation and maintenance activities is of paramount importance.

I am sure that this Handbook will help and encourage operation and maintenance personals for constant monitoring and taking immediate remedial actions through OMC-R & OMC-S for improving QoS parameters. This Handbook will help to solve problems related to: handover issues; call drop issues; SDCCH/TCH congestion; SDCCH/TCH blocking; VSWR issues; call setup success rate; etc.

Basic guidelines also on conducting Drive Test, Optimisation, etc has been provided for field personal who will immediately be able to start drive testing and RF optimisation activities. This Handbook is only the beginning and suggestions for improvement may be sent by email to [email protected]

I thank Dr Biswajit Paul SrGM/CM Orissa Circle and other officers of East Zone Circles for their hard work and sincere efforts to bring out this much desired Handbook. I also thank Shri Shyam Narain, Dr S K Samanta, Shri Kishore Bhagtani, and other officers of BSNL CO for their valuable contribution.

Preface

A comprehensive handbook for O&M activities to be undertaken by the field engineers and technicians is one of the most critical pieces of document and is required in hand for smooth maintenance as well as speedy resolution of various issues. There has always been a need of one comprehensive book for resolving most of the day to day issues faced by network engineers and technicians in the field.

This handbook is a result of an idea initiated by Shri R K Mittal, DIR (CM) BSNL Board and translated by teams of experienced officers of various levels both at BSNL Corporate Office and in the Circles. The final version is compiled by Dr S K Samanta AddlGM (NWO-CM) and Shri Kishore Bhagtani DGM (NWO-CM) BSNL Corporate Office under the guidance of SrGM (NWO-CM) BSNL CO and Dir (CM) BSNL Board.

This Handbook will not only help the existing officers, engineers and technicians in SSAs and circle offices, but will be very much useful to those new personnel, who will be posted for day to day operation and maintenance activities for CMTS networks of Ericsson Technologies in the coming days.

Acknowledgements

Following officers of East Zone actively contributed for the preparation of this handbook under the guidance of Dr Biswajit Paul, Sr GM (NWO-CM) Orissa Circle

Orissa Circle

Gurudas Meher, GM CM, BSNL Odisha (Contact 94371-77700, [email protected] ) BC Panda, DGM Core NW, BSNL Odisha (Contact 94370-82555, [email protected]) PK Sahoo, SDE MSC Cuttack, BSNL Odisha (Contact 94370-55400, [email protected] ) Prabir Sahoo, SDE RF, Rourkela, BSNL Odisha (Contact 94370-14200, [email protected])

Calcutta Telecom District

Debjit Saha, DE RF, BSNL Kolkata (Contact 94330-00419, [email protected] ) Assam Circle

Raju Sutradhar, JTO CMTS, BSNL Assam (Contact 94350-25262, [email protected] ) M/s Ericsson

Ramesh Chandra Dimri of M/s EIL has provided valuable suggestions for simple explanation on the technical issues.

INDEX

Sl. No Topic Page No

1. Introduction 9

2. BTS 12

2.1. BTS Function and Block Diagram 12

2.2. BTS Preventive Maintenance 14 2.2.1. General Inspection of BTS 14 2.2.2. Monthly Routines 16 2.2.3. Quarterly Routines 16 2.2.4. Half-yearly Routines 17 2.2.5. Annually Routines 17

2.2.6. Logs and Records 17

2.3. BTS Fault Monitoring, Alert and Rectification Mechanism 17

2.3.1. Fault Monitoring 17

2.3.2. Fault Alert Mechanism 18

2.3.3. Fault Rectification Mechanism 18

2.4. BTS Health checkup & Routine Maintenance 18

2.4.1. Winfiol 18

2.4.2. Health Ckeckup & Maintenance 23

2.4.3. OMT Software 32

3. QoS of Radio Network – 2G 33

3.1. Report Analysis 33

3.2. Improvement of 2G Data Services 37

3.3. Case Study 39

4. BSC 46

4.1. BSC Function 46

4.2. BSC Hardware 47

4.4. BSC Fault Monitoring, Alert and Rectification Mechanism 51 4.5. BSC Health Checkup & Routine Maintenance 52

4.5.1. Daily Health Checkup 52

4.5.2. Weekly O&M Routine 70

4.5.3. Monthly O&M Routine 72

5. 3G Radio Network 76

5.1. Node B Hardware Description 76

5.2. Node B Preventive Maintenance 86

5.2.1. General Inspection of Node-B 86

5.2.2. Monthly Routine 87

5.2.3. Quarterly Routine 87

5.2.4. Half Yearly Routine 88

5.2.5. Annual Routine 88

5.2.6. Log & Records 89

5.3. Node B Fault Monitoring, Alert & Rectification Mechanism 89 5.4. Node B Health checkup & Routine Maintenance 90

6. RNC 96

6.1. RNC Function 96

6.2. RNC Hardware 102

6.3. RNC Health Checkup & Routine Maintenance 106

6.4. Alarm & Analysis 119

7. QoS of Radio Network – 3G 128

8. Drive Test 140

8.1. Purpose of Drive Test 140

8.2. When to Undertake Drive Test 140

8.3. Where to Undertake Drive Test 140

8.4. Route Plan 141

8.5. Drive Test Tools 141

8.7. Log File & Export 145

9. Management Reports 155

9.1. On Daily Basis 155

9.2. On Monthly Basis 155

9.3. Sample Management Report 156

10. BTS Inspection 158

11. Radio Network Optimization 162

12. Event based Recording for Efficient Optimisation of 3G RAN 179

13. Minilink Operation & Maintenance 184

13.1. Minilink Hardware 184

13.2. MSM Program 188

13.3. Fault Management 189

14. MPBN Monitoring 196

14.1. Port Status 196

14.2. Error Counter Check & Reset 196

14.3. Temperature measurement in MPBN Router & Switch 197

15. Frequently Asked Questions 200

16. Exchange Data Backup Procedure 207

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1. Introduction

A mobile network consists of: a) a access part - Base Station Subsystem (BSS); and b) a core part - Network Subsystem (NSS). BSS Networks consists of: Base Transceiver Stations (BTS) and Base Station Controller (BSC). NSS Networks consists of: Mobile Switching Centre (MSC), Home Location Register (HLR), Visitor Location Register (VLR), IN and Billing & Customer Care Systems (B&CCS).

1.1. BSS Networks

The main components of BSS networks consists of two parts: i) Radio - BTS, BTS-BSC links, BSC and ii) Infra - Tower, Diesel Generator (DG), Air Conditioners (AC) or Free Cooling System (FCS), -48 Volt Battery and Power Plant. BTS to BSC links are either provided through OFC networks (i.e. CPE, ADM. MADM, etc) or through Digital Microwave (i.e. Mini Link).

Schematic Diagram of a BSS BTS MS BSC MSC HLR/AuC/EIR GMSC BSC BSC SMSC/MMSC Other Networks (PSTN, Mobile & Data Networks) Internet GGSN PCU Packet Handling Nodes MS IN/Billing VLR BTS BTS SGSN Router BTS MS BSC MSC HLR/AuC/EIR GMSC BSC BSC SMSC/MMSC Other Networks (PSTN, Mobile & Data Networks) Internet GGSN PCU PCU Packet Handling Nodes MS IN/Billing VLR BTS BTS SGSN Router

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1.2. Base Transceiver Stations (BTS): BTS or access nodes provides connection to a user through a wireless local loop, with authorisation for access and call managed by HLR, VLR, IN and B&CCS. The wireless loop is only used when a call is in progress and is shared among the BTS users served in a geographical area; this typically covers a radius up to 20km (if there is no obstruction e.g tall buildings). The traffic from several BTS’s is multiplexed at the Base Station Controller (BSC) which relays to the Mobile Switching Centre (MSC) thus providing the connection between users. A BTS is designed according to: minutes of call, number of messages and amount of Data to be provided in a specific time period. Assuming a BTS is designed to handle 1000 minutes of calls per hour, it could provide 200 users with 5 minutes or alternatively 500 users with 2 minutes of calls. It is clear there can be more users if the call duration is less. This is not the case in a wire line network where a dedicated connection from the access node is provided for each user. This characteristic of mobile networks suggests a different strategy be folowed in providing desired Quality of Services (QoS) to Mobile users.

A successful call/connection uses two links for transport of information: 1) originating links: and 2) terminating links. When both the links of a call are provided by the same BTS it is defined as intra BTS call otherwise it is called inter BTS call. Both the intra BTS and inter BTS call passes through BSC and is switched at MSC. When a call is terminated in a network managed by a different operator it is routed via a Gateway MSC (GMSC).

Authorisation for access to the mobile network to a user is done by allocating a unique mobile number against the subscribers’ Service Identity Module (SIM) and creating a matching data base in the HLR. The Mobile Equipment (ME) with the SIM inserted in it is generally called the Mobile Station (MS) and communicates to HLR through BTS, BSC and MSC to get access to the network.

Components such as the BTS, BSC and their interconnections are used for the transport of all services, whereas components like MSC and links between BSC-MSC and MSC-GMSC are only used for voice and low speed Data such as the Short Message Service (SMS). For message services like SMS and Multimedia Message Services (MMS) additional nodes such as Short Message Service Centre (SMSC) and Multimedia Message Service Centre (MMSC) are used to store and forward the message.

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Traffic such as a voice call is carried through a Traffic Channel (TCH) which transports information usually measured in kbps (kilo bits per second). For a full rate voice call each TCH carries 12.2 kbps whereas the Data rate per TCH can be up to 59.2 kbps depending on the modulation scheme and technology e.g. GPRS or EDGE. A BTS configured with 4 carriers per sector i.e. total 96 channels is generally connected to a BSC with a 2 Mbps (Millions of bits per second) link i.e. 1E1. This 2Mbps is not sufficient for high Data usage customers in urban areas and therefore 2 nos of 2Mbps links i.e. 2E1 per BTS to BSC is required.

Smart Phone users heavily uses Data services such as e-mail, browsing, download and audio/video streaming and these services do not use elements such as the MSC and BSC-MSC links. Technologies such as General Packet Radio Service (GPRS), Enhanced Data rates for GSM Evolution (EDGE), third Generation (3G) and forth Generation (4G) are generally employed for these Data services. It uses Packet Handling Nodes (PHN) such as Packet Controller Units (PCU), Serving GPRS Support Nodes (SGSN), Gateway GPRS Support Nodes (GGSN) and Routers in place of MSCs. The resources of BTS, BSC and interconnected links are used to update the location by each active mobile set even in the idle state. The volume of such traffic is small but adequate no of communication channels need to be defined.

The authorisation to access a mobile network is controlled by elements such as the HLR, the Authentication Centre (AuC), the Equipment Identity Register (EIR), the VLR and IN/B&CCS. HLR, AuC and EIR is normally configured in the same hardware and in general there are two systems (1 + 1) for each geographical area ( circle ) for redundancy purposes. An HLR can provide access to the tune of 10.0 million subscribers and can be connected to more than one MSC. Each MSC is paired with a VLR which temporarily stores the data for the customers who visits the area under the radio coverage of the BTSs connected to the MSC.

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2. BTS

2.1

A. RBS 2206: RBS 2206 consists of five main units: DXU; TRU; CDU; CXU; and IDM. Picture of a sample RBS 2206 is given below.

DISTRIBUTION SWITCH UNIT (DXU)

The Distribution Switch Unit (DXU) is the RBS central control unit. There is one DXU per RBS. It provides a system interface by cross connecting 2Mbit/s transport network and individual time slots to their associated transceivers.

TRANSCEIVERUNIT (TRU)

It is a transmitter/receiver and signal processing unit which broadcasts and receives the radio frequency signals that are passed to and from the mobile station. Each TRU handles 8 airtime slots (i.e. TCH).

COMBINING AND DISTRIBUTION UNIT (CDU)

A combiner is a device, at the base station, that allows connection of several transmitters to one antenna. It allows each transmitter’s RF energy out to the antenna, while blocking the RF energy from the other transmitters utilizing the same antenna. There are two types of combiners:

 Hybrid  Filter

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Configuration Switch Unit (CXU)

The Configuration Switch Unit (CXU) distributes the Receiver (RX) signals from the Combining and Distribution Unit (CDU) to the double Transceiver Unit (DTRU) within the same RBS.

Internal Distribution Module (IDM) • Supplies +24DC to the system

• Has fuses and breakers for protection • Has +24V DC filter for battery connections •

The main units in the power and climate system are: Power Supply Unit (PSU)

• Provide +24V DC to the system • Available in two versions.

• PSU AC for 200~250VAC (Rectifier).

• PSU DC for -48V system. (Converter dc to dc). • Number of units 0-3.

• Additional units required to reduce battery charging times. • AC Connection Unit (ACCU)

• DC Connection Unit (DCCU)

• Fans controlled by Fan Control Units (FCU)

• Climate sensors, i.e. temperature and humidity sensors LOCAL BUS

The local bus offers internal communication between the DXU, TRUs and ECU. Examples of information sent on this bus are TRX Signalling, speech and data.

TIMING BUS

The timing bus carries air timing information from the DXU to the TRUs. CDU BUS

The CDU Bus connects the CDU to the TRUs and facilitates interface and O&M functions e.g. transfers alarms and RU specific information.

IOM BUS

This interface consists of three individual I2C ports. It is used to communicate with the CDU, CXU, TMA-CM and cabinet ID.

B. RBS 2964: RBS 2964 consists of PSU; DXU; DRU; and IDM . Picture of a sample RBS 2964 is given below.

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Dual Radio Unit (DRU) Consists of • 2 GSM TRX • Hybrid combiner • 2 TX filter • 2 duplex filters • 2 bias injectors • Number of units 1-6(12 TRX) Y-Links

• Replaces Timing Bus, Local Bus and X Bus

• New point-to-point interface between DXU & TRUs

• Based on LVDS,( Low Voltage Differential Signalling) interface • Backplane connector on DXU with compatibilityof 2102/2202 cabinets • Each DRU has two Y links (one for each transciver)

• Each Y link is divided into two interfaces: • Y1: TX control data

• TX burst data (X Bus data) • Y2: Traffic data UL & DL • O&M Data

• Timing

2.2 BTS Preventive Maintenance

2.2.1 General Inspection of BTS

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Equipment related checks

Check for any fault in the unit or any other alarms

No visual damage to the equipment or site room is evident The waveguides and connectors are fixed properly

The equipement and the place should be kept clean and cleaning schedule should be maintained sincerely

It should be ensured that all external alarms are extended and are working properly

Environment

Air conditioners are functioning correctly. There is no leakage of air-conditioned air through door, window or waveguide openings. The air inlet / filters to the cabinet are clean

Indoor light is working & Indoor emergency light is working

Check for any surrounding activities or changes close to the site that may affect the performance of the system or safety of the equipment

Battery / Power plant / DG

All modules of SMPS power plant are working properly and load is being shared by all.

Check back-up batteries for corrosion and leakage.

Check the run time of Engine Alternator and compare it with the manufacturers’ recommended service interval regarding the run time and ensure regular service.

The oil in the Engine Alternator should be checked with the dipstick to ensure its sufficient level and also its usefulness.

Earthing

It should be ensured that Earth resistance value has been measured once in every six months and the same is displayed. It should be less than 0.5 ohm.

Fire Safety Expiry date on Fire extinguisher and sufficiency of fire safety equipments.

Tower Check that the navigation light on the tower is operational and condition of tower with regard to its painting etc is OK.

Other The media connectivity record should be maintained in a database.

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 Climate control i.e. air conditioners are functioning correctly. There is no leakage of air-conditioned air through door, window or waveguide openings.

 The air inlet / filters to the cabinet are clean.

 The oil in the Engine Alternator should be checked with the dipstick to ensure sufficient level and also its usefulness.

 Functioning of all alarms is tested for service worthiness.

 Weak cell of batteries to be identified and remedial action should be taken.

 Check for logical parameter inconsistencies like Half Rate parameters modified in OMCR but not getting reflected in traffic report in terms of half rate erlang.

 Audit of adjacencies and RF parameters like BCCH / BSIC/ HSN. Number of adjacencies should be optimized. It should be monitored whether all defined adjacencies takes traffic or not. Extra neighbours should be removed. Missing neighbours should be added. Cells having high ratio of handover traffic to cell originating traffic should be studied further for improvement.

 Audit of 2G / 3G adjacencies should be carried with consideration of BCCH / BSIC.  Nearby cells having same BCCH / HSN should be identified and modified

2.2.3 Quarterly Routines

The following should be checked once in a quarter in addition to the regular daily and weekly check-ups:-

 Check BTS rack filters and replace if necessary.

 Carry out battery back-up voltage test, to ascertain whether the batteries are holding their full charge.

 Check the site temperature and humidity.

 Updation of data in the planning tool based on results of Drive Tests during the quarter.  Cell Planning and RF Planning should be reviewed for any possible error or change in

situation due to addition, deletion or change in configuration of BTS in the network.

 Any additional BTS should be put in service only after A/T and special monitoring on Call Success Rate (CSR) in all cells in the BSC is necessary so as to be sure that it is not impacting the performance of any other sector/ cell adversely.

 Temperature monitoring

 In case of shelter sites: - free cooling filter should be cleaned

 In case of outdoor site: - all canopy fans should be in working condition

2.2.4 Half-yearly Routines

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 Power measurement of the BTS should be done.  The waveguides and connectors are fixed properly.

 VSWR should be measured once in six months for every BTS and its value should be maintained within the limit (<1.3) for all waveguides.

 Earth resistance should be measured for all BTS sites. The value of earth resistance in respect of DC earth, Tower earth and AC earth should beless than specified value.

 It should be checked if there is any leakage for A/C as the same increases load on the plant and also power consumption. It also needs to seen that penalty is not being imposed by Electricty Boards on account of power factor, over consumption etc.

2.2.5 Annual Routines

 Waveguide termination weather proofing

 Site cleaning - inside shelter / canopy & surrounding area (particularly @ NBSNL sites )  Mini link status (Antenna orientation – tighten, receive power check etc.)

2.2.6 Logs and Records

Log book has to be maintained at each BTS.

 Daily Log for all activities at BTS including the outage.  Power & Engine Alternator run log book

 To maintain spare-part list at each SSA

 To maintain complaint register at SSA for network related problems.

 To maintain list of sites which fail frequently, identify the root cause and take corrective action.

2.3 BTS Fault Monitoring, Alert and Rectification Mechanism

2.3.1 Fault Monitoring

 Faults are being continuously monitored on 24 X 7 by NOC / OMCR personnels.  As and when any fault occurs in the network it is indicated on OMCR monitor.

2.3.2 Fault Alert mechanism

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 24X7 NOC / OMCR staff escalates the fault to the concerned persons/ field staff.

 Software based automatic alert system is put in place which informs the faults to the concerned staff through SMS

 The concerned officer identifies the fault reason like media problem / power supply problem / equipment related problem

2.3.3 Fault Rectification Mechanism

Fault Action to be taken

Media The section is to be identified and concerned officer is being informed for furher rectification.

Power

 If the power supply is disconnected, it should be ensured that Battery is taking load and if required DG set should be started.  If there is problem of power plant module, it should be replaced. Equipement

related

 Soft reset should be given from OMCR  Hard reset should be given from the site  Faulty Y-link cable should be replaced.

If required faulty cards (DXU, TRU etc) should be replaced. Enviorment

(High

Temperature)

 Check Air condition working  Check Free cooling system

 Check in case of out door BTS - Canopy Fan or Door Fan

In case of BTS equipement related problem, site visit is required for further investigation and action.

2.4 BTS Health Checkup & Routine Maintenance

For Command level health checkup Winfoil has to be loaded in the work station / laptop.

2.4.1 Winfiol

WinFiol: WinFiol is a software developed by Ericsson for operation and maintenance of Ericsson systems, which includes mainly core network and BSS.

Installation of WinFiol: The WinFiol installation offers Complete Setup, Custom Setup and Compact Setup. Normally we chose Complete Setup. Select the Next button to go through the installation process, and the Back button to return to the previous page to change any options.

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Creating new Channel:

1> After opening WinFiol, go to Channel then select new

2> Click Open

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[Note: If you have already created a channel then, right click on the channel, and go to properties.]

Setting Up the Channel Properties: 1> Provide Channel name.

21

3> Chose mode.

4> Provide Host name [the IP address of OSS (Operation & Support System) connected to the 2G network]. Provide Port number, Terminal type.

22

23

Understanding the Channel window

When you open a channel normally two windows are shown, the upper window is the Output window, and the lower one is the Input Window. You can toggle between windows by using Alt+F5.

Ericsson Commands

1> Logging into BSC with new channel: Whenever you open the channel that you have just created, will ask for User ID and Password.

Login :<UID> Password:<PW> After that you are connected to the OSS.

Now to enter into BSC, run the command:

eaw {BSC NAME} [Note BSC name in CAPITAL LETTER]

2.4.2 HEALTH CHECKUP AND MAINTENANCE

1. To check various class of alarms in BSC:

For example, High room temp, Door open…, A2 stands for INTERNAL. For example, Permanent fault, OML FAULT, Loop

are shown, A3 stands for critical alarm]

ALLIP; [To show all type of alarm] 1.1 ACL=A1

1.2 ACL=A2

1.3 ACL=A3

2. To check the status of the sites and cells in the BSC:

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For example, High room temp, Door open…, A2 stands for INTERNAL. For example, Permanent fault, OML FAULT, Loop Test Fault, Local Mode….Date and Time of all alarms are shown, A3 stands for critical alarm]

[To show all type of alarm]

To check the status of the sites and cells in the BSC:

For example, High room temp, Door open…, A2 stands for INTERNAL. For example, Test Fault, Local Mode….Date and Time of all alarms

2.1 RLCRP: CELL=ALL;

BCCH: Number

CBCH: Number of CBCH available for the sector. SDCCH: Number of SDCCH available for the sector. NOOFTCH: Number of TCH available for the sector.

[Note: If the sector is down, all values will be 0, 0] 2.2 RLCRP: CELL=CAL875A;

CHANNEL: Type of channel i.e. TCH/BCCH/SDCCH/CBCH.

25 RLCRP: CELL=ALL;

Number of BCCH available for the sector. Number of CBCH available for the sector. Number of SDCCH available for the sector. Number of TCH available for the sector. [Note: If the sector is down, all values will be 0, 0]

=CAL875A; (to check status of all cells)

Type of channel i.e. TCH/BCCH/SDCCH/CBCH. Type of channel i.e. TCH/BCCH/SDCCH/CBCH.

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STATE: State of the channel BUSY/IDLE.

USE: Type of service, the channel is being used for, SPEECH/GPRS.

3.

To check whether a cell is Active or Halted

RLSTP: CELL={SECTOR ID};

3.1

To Halt or To Active a cell

RLSTC: CELL= {SECTOR ID}, STATE={STATE}; [Note: STATE=HALTED/ACTIVE]

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4. To Check the Hardware alarms of a Site

RXTCP: MOTY=RXOTG, CELL={SECTOR ID}; [To see the Trunk Group]

RXASP: MO= RXOTG - {TG No.}; [For checking general Alarms]

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OML FAULT: Optical and Maintenance Link fail (Normally it indicates media is break.)

PERMANENT FAULT: The equipment is permanently down due to some reason. (You can try to block &

deblock the equipment, sometimes after blocking/deblocking, equipment starts

working)

LOCAL MODE: TRU in local mode & sometimes DXU in local Mode

Here some alarms can be seen like “BTS EXT UNAFFECTED”, “BTS INT AFFECTED”, “BTS INT UNAFFECTED”. In that case we have to determine the Fault Code to know the exact problem.

RXMFP:MO =RXOCF - {XX}; [To know the Fault Code, Class No & =RXOTRX - {XX}; Replacement Unit No., Problem can be =RXORX - {XX}; identified by using RBS Fault Decoder] =RXOTX - {XX};

=RXOTF - {XX}; =RXOTS-{XX}

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By putting fault code in “rbs fault decoder” we can know the fault details. Also locally in BTS by connecting “OMT software” we can know.

After knowing the fault type i.e. vswr fault/rx diversity /card h/w fault. We shall take necessary action.

5. To Check the DIP(PCM) status of a site

RXTCP: MOTY=RXOTG, CELL={SECTOR ID}; [To determine TG No.] RXAPP: MO=RXOTG – {TG NO}; [To see RBLT]

Observe the first RBLT number: RBLT2 – 10977

Divide the number (10977-1) by 32, get the DIP no 343. DCP=1 to 31: PCM is connected to A port of DXU at BTS. DCP= 287 to 317:PCM is connected to C port of DXU at BTS. DTSTP: DIP={DIP No};[To Check Status of Digital Path]

[Observe STATE here, WO=> Working, ABL=> Automatically Blocked (PCM Fail), MBL => Manually Blocked]

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6.

To Check the DIP(PCM) transmission quality

[Note: here values of N-ES, N-SES, SLIP, SFV, etc. are all measures of error values of the PCM, large values of which indicate poor performance of the PCM. T1 value is shown in minutes, T2 value is shown in hours]

7. To RESET error in DIP(PCM)

DTQSR: DIP= {DIP NO},es,ses; DTQSR: DIP={DIP NO},unacc,degr;

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8. BASIC MO COMMANDS

8.1 RXTCP: MOTY=RXOTG; (Shows cells connected to TG)

8.2 RXMOP: MOTY=RXOTG; (Shows all TG parameters)

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RXMOP:MOTY=RXOTF; (Shows TF mode and SYNC source of site) RXMOP:MOTY=RXOCON; (Shows DCP value of CON)

RXMOP:MOTY=RXOTRX; (Shows TEI,Signalling,CELL,DCP values of TRXs) RXMOP:MOTY=RXOTX; (Shows CELL,Band,ChlGroup,MaxPower of TXs) RXMSP:MOTY=RXOTRX; (Shows the status of TRXs)

RXASP:MOTY=RXOTG; (shows the Alarms of TGs)

By using RXMFP command we will also get h/w details of a card i.e. Product code,Sl no, etc.

2.4.3 OMT SOFTWARE:

OMT software is being loaded in Laptop for monitoring of BTS in BTS location.

1. It is very useful at site. It can be used locally to know all the information about site i.e. configuration, alarms etc.

Connect->Read IDB ->OMT -> DISPLAY INFORMATION ->Installation DataBase->Display-> Information

2. It is required for any card addition, E1 addition, Cascading, Configuration change, TEI value change, Sector addition/deletion.

OPEN OMT->CREATE IDB->CONNECT->MAKE LOCAL DXU->INSTALL IDB-> RESET DXU

When a site is not working in spite of no faults, we must check the

A) The TEI value of DXU in BTS by IDB and defined TEI value of CF in BSC. B) The PCM terminated at A port or C port and defined DCP value in BSC.

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3 QoS of Radio Network – 2G

3.1

Important KPIs (Key performance Indicators) are to be monitored and analyzed on regular basis.

Important 2G VOICE KPIs are:

i. BBH Call/ TCH drop (Should be <3%) ii. BBH TCH Block (Should be <2%) iii. BBH SDCCH Block (Should be <1%) iv. BBH HSR (Should be >95%)

v. BBH CSR (Should be >95%) vi. BBH Traffic

BBH means Busy Bouncing Hour of the Cell or BSC. The above KPIs can be analyzed directly from Ericsson BO Reports

RADIO-->BBH_Report_Cell_RC5.3_rev1. ( For BBH of Sectors/ Cells) RADIO-->Performance_Overview_BSC ( For Whole day of BSCs)

3.1.1 There are several reasons for poor KPI (Call Drop, TCH Block, SDCCH Block, HSR and CSR). In this handbook, the faults are being explained as follows---SDCCH Block/ Congestion

Reasons---

a. Check carried Traffic (Erlang) from BO Report

b. Defining Proper No of SDCCH Channels (Default value:upto 2TRX->SDCCH 1 TS,above 2TRX to 4TRX->SDCCH 2 TS, above 4TRX to >SDCCH 3 TS,above 6TRX->SDCCH 4 TS.) (use command RLCCC)

c. Dynamic SDCCH may be defined (use command RLACI)

d. Check Hardware Faults and Transmission Alarms (use command RXASP) e. Problem in TRX in which SDCCH is defined etc.

If a cell having SDCCH blocking with less TCH traffic, then increase the SDCCH in that cell.

RF TEAM ACTIVITY--- a. Optimize LAC boundary

b. BTS Boundary ==Define sufficient SDCCH Channels

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3.1.2 TCH Block/ Congestion---

a. Check carried Traffic (Erlang) from BO Report b. Check Hardware Faults and Transmission Alarms

c. Check TRX and Time slots Faults—(Idle/ low traffic handling TRX)

d. Power adjustment (BS TX Power max)(in exceptional cases) (using command RLCPC) e. AMRHR may be done (using command RLDHC)

f. Lowering of HR triggering thresholds.

g. Directed retry/Traffic Handover may be enabled.( RLLBC: ASSOC= ON)----In BSC, ( RLLOC) In Cell

RF TEAM ACTIVITY---

a. Antenna Adjustment for Serving Cell/Neighbour Cells– Increasing Mechanical/Electrical tilt , Lowering Antenna Height , Changing Antenna Azimuth etc.

b. Planning for additional Cabinet (1800 band) or increasing TRX/ rearranging the existing configuration.*

c. Load sharing in OL/ UL on basis of Path loss Criteria d. Fourth sector may be introduced at the same BTS. e. Last option: Introduction of new BTS

3.1.3 TCH/ Call Drop

a. Check Hardware Faults and Transmission Alarms (Command RXASP) b. Check Transmission error (Command DTQUP)

c. Due to Interference (ICM Band value should be=<3) (Command RLCRP) d. Check VSWR/ RF cable alarms (Command RXMFP)

e. Check Hopping Frequency, MAIO and HSN(Command RLCHP,RLCFP) h. Check TRX and Time slots Faults—(Idle/ low traffic handling TRX)

i. Check Intra and Inter Handover definitions—(Inter BSC and Inter MSC)(Command RLNCP,RLNRP)

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j. Check the parameter value like RLT, Rx lev. Access min., RACH Access min as per situation.

k. Congestion of Target Neighbour sites l. Nearby Sites Down

RF TEAM ACTIVITY--- a. Sectors Swapping to be checked

b. Intra Sectors cable Swap (Diversity Cable) to be checked c. Improper Frequency Planning (BCCH/ BSIC) to be monitored d. Handover Failure (Intra BSC, Inter BSC, Intra MSC, Inter MSC) e. 3G to 2G handover & vice-versa (IRAT) definition to be checked.

f. If neighbour is missing define the neighbours& if exists then delete and recreate if Handover is not happening properly.

g. Poor signal strength/quality in UL/DL path to be checked h. External Interference to be analyzed.

3.1.4 Poor Handover Success Rate

a. Check Hardware Faults and Transmission Alarms

b. Check Intra and Inter Handover definitions—(Inter BSC and Inter MSC) c. Congestion of Target Neighbour sites

d. Missing neighbour/Too many neighbours RF TEAM ACTIVITY

a. Sectors Swapping to be checked

b. Intra Sectors cable Swap (Diversity Cable) to be checked c. Improper RF planning mainly same BCCH/BSIC to be checked. d. Frequent Inter MSC/Inter BSC handovers to be checked.

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3.1.5 Poor Call Setup Success Rate---

a. Check Hardware Faults and Transmission Alarms b. Check TCH Congestions

c. SDCCH Congestion/Drop d. Check Transmission error

e. Check VSWR/ Rx Diversity alarm s (code 2A 8,2A 57,2A 33 in CF) RF TEAM ACTIVITY---

a. Bad RF environment like poor Rxlev/Qual/TA b. Intra Sectors cable Swap (Diversity Cable) c. Improper RF planning mainly same BCCH/BSIC d. External Interference

All above mentioned point to be checked & analyzed

The following points may be taken care to improve the QoS  Signalling of all TRX and CF should be in CONC mode.  Cascading of 2nd _cabinet.

 Check the 3G reselection and Handover(Use command RLSUP,RLUMP) Rldep: cell=all,utran,ext; (for checking utran external cells)

Rldep: cell=urk0012; (for checking parameters of utran cells)

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3.2 IMPROVEMENT OF 2G DATA SERVICES

Performance of 2G DATA are to be monitored and to be analyzed on regular basis. Important 2G DATA Reports and parameters----

1. Busy Hour/ Whole Day Traffic( Both Uplink and Downlink) 2. Average/ Peak Throughput

3. Packet Channel Allocation Attempts and Failure 4. GSL Device Utilization ( PCU- RPP Card Utilization) 5. RPP Card Load

6. Gb Utilization (Gb interface over Frame Relay)

7. No. of Channel GPRS/ EDGE dedicated and dynamic---OMC-R 8. No. of PCM connected to BTS---OMC-R

9. Version/ Type of BTS---OMC-R

All the above report can be analyzed by generating BO report

The following step should be taken for improvement of GPRS speed in 2G: 1) Sig = CONC instead of MPLEX16 (using rxmoc command)

2) TN7BCCH= EGPRS (using rlbdc command)

3) Try to define edge bpc on Chgr=0 (on Non Hopped channel, numreqegprsbpc value should be at least 4 for 4-4-4 site, 6 for 6-6-6 sites.3 for 2-2-2 sites per sector. If there is shortage of BPC in CHGR-0 then we can also define edge bpc in CHGR=1. (Use RLBDC )

4) FPDCH=Number of fixed Edge channel. Dedicated mode is to be implemented for guaranteed data service where Voice Traffic is more otherwise all Timeslots may be in dynamic mode. Also Semi-dedicated channel can be introduced. In dedicated mode maximum recommended value is 2 or 1. If it is set to higher value then voice traffic may be effected. (Use RLGSC command)

5) CHCSDL =CS4 (using RLGSCcommand)

6) Streamsup=yes, epdchbr=32 (using RLGQC command)

7) Number of data user more, then increase the PRACHBLK=4 (using rlpdc command) 8) Abis allocation should be flexible (rxmoc:mo=rxotg-xx, abisalloc= flexilble;)

9) To check no. of 64k device in Abis path (rxapi: mo=rxotg-xx, dcp=xx, device=RBLT-xx, res64k)

The following activities in Ericsson BSC required for increasing the 2G data speed--

1. Check how many RPP cards are equipped. 1 RPP card= 64 data Time Slot. If equipped with 7 RPP cards, then total resources are 448 Time slots (7x64=448).

2. All timeslots may be in dynamic mode. Also semi-dedicated channel can be introduced. We need to ensure more 64K channel (At least 7 64K channel) needs to be defined in TG for ensuring more use of E-PDCH rather than B-PDCH and also more Number of EDGE BPC defined in a cell.

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3. Check for the configuration of 100Mbps data & no error on Gb over Ip link from BSC to MSC-MPBN router.

4. Augmentation 2nd PCM for every BTS dedicatedly for GPRS is recommended where GPRS traffic is high.

5. Also RTGPHDEV congestion to be monitored form GSL Device utilization report. GB over Frame Relay should be migrated to GBoIP as it will ensure some more devices towards radio link. If RTGPHDEV congestion is more than 90% RPP card is to be added. If 7 RPP card already in use then New RPP magazine need to be introduced to reduce RTGPHDEV congestion. (use STDEP:DEV=RTGPHDEV=”dev no” to check RTGPHDEV Congestion ) Whether GPRS is enabled in cell or not can be checked by the following command.

RLGSP: CELL= {cell name}

In Cells having UL/OL concept implemented, set SCALLOC=BOTHOL (Use RLGSC). Otherwise GPRS will be available in Under-laid Sub-cell only.

How many EGPRS BPC defined in a cell can be checked by the following command. RLBDP: CELL= {cell name};

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3.3 CASE STUDY

3.3.1 Special Case: To increase coverage of the Cell where traffic is less, mainly in rural area. TCC (Transmitter Coherent Combining) Implementation

It will be done in cells having 4 TRX. By doing this the configuration will be reduced to 3TRXs but coverage will be increased to around 1 to 1.5 km. The cell will work on under laid and overlaid sub-cell concept.

RLSTC:CELL=KAN001A,STATE=HALTED; RXBLI:MO=RXOTRX-182-0,SUBORD,FORCE; RXESE:MO=RXOTRX-182-0,SUBORD; RXBLI:MO=RXOTRX-182-1,SUBORD,FORCE; RXESE:MO=RXOTRX-182-1,SUBORD; RXBLI:MO=RXOTRX-182-2,SUBORD,FORCE; RXESE:MO=RXOTRX-182-2,SUBORD; RXBLI:MO=RXOTRX-182-3,SUBORD,FORCE; RXESE:MO=RXOTRX-182-3,SUBORD; RXMOC:MO=RXOTX-182-0, BAND=GSM900, MPWR=51; RXMOC:MO=RXOTX-182-2, BAND=GSM900, MPWR=51; RXMOC:MO=RXOTX-182-3, BAND=GSM900, MPWR=51; RXMOC:MO=rxotrx-182-0,CELL=KAN001A,CHGR=0; RXMOC:MO=rxotrx-182-2,CELL=KAN001A,CHGR=1; RXMOC:MO=rxotrx-182-3,CELL=KAN001A,CHGR=1; RLDSI:CELL=KAN001A; RLCPC:CELL=KAN001A,SCTYPE=OL,MSTXPWR=33; RLCPC:CELL=KAN001A, BSPWRT=47,SCTYPE=OL; RLDGC:CELL=KAN001A,SCTYPE=OL,CHGR=1; RLDEC:CELL=KAN001A,IRC=ON; RLOLC:CELL=KAN001A,LOL=125,LOLHYST=2, TAOL=61,TAOLHYST=0; RLLOC:CELL=KAN001A,SCTYPE=OL,BSTXPWR=51;

40 RLCPC:CELL=KAN001A, BSPWRB=51; RLCPC:CELL=KAN001A,SCTYPE=UL,BSPWRT=51; RLCPC:CELL=KAN001A,SCTYPE=UL,MSTXPWR=33,BSPWRT=51; RLHPC:CELL=KAN001A,CHAP=6; RLLLC:CELL=KAN001A,SCLD=ON,SCLDLOL=20,SCLDLUL=40,SCLDSC=OL; RLPCC:CELL=KAN001A,SCTYPE=UL,SSDESUL=90,QDESUL=30,LCOMPUL=6,QCO MPUL=70; RLPCC:CELL=KAN001A,SCTYPE=OL,SSDESUL=90,QDESUL=30,LCOMPUL=6,QCO MPUL=70; RLLPC:CELL=KAN001A,PTIMBQ=15; RXMOE:MO=RXOTRX-182-1; RXMOE:MO=RXOTX-182-1; RXMOE:MO=RXORX-182-1; RXMOE:MO=RXOTS-182-1-0&&-7; RXESI:MO=RXOTRX-182-0,SUBORD; RXBLE:MO=RXOTRX-182-0,SUBORD; RXESI:MO=RXOTRX-182-2,SUBORD; RXBLE:MO=RXOTRX-182-2,SUBORD; RXESI:MO=RXOTRX-182-3,SUBORD; RXBLE:MO=RXOTRX-182-3,SUBORD; RLCCC:CELL=KAN001A,SDCCH=0,CHGR=1; RLCCC:CELL=KAN001A,SDCCH=2,TN=2&3,CHGR=0; RLBDC:cell=KAN001A,NUMREQBPC=16,CHGR=1; RLGSC:CELL=KAN001A,SCALLOC=BOTHOL; RLSTC:CELL=KAN001A,STATE=ACTIVE;

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3.3.2 To add no. TRXs in the Cell or to add new sector in the site where traffic

is more.

CONFIGURATION

Besides general type of configuration (2+2+2, 4+4+4)

According to traffic we can also make it 2 sector with configuration 4+4,6+6,4+8 and 8+4.

 In 2964 cabinet:

According to traffic, we can make such type of configuration with 3 sectors:

2+2+4,2+2+6,2+2+8,2+4+2,2+4+4,2+2+2,4+4+4,4+2+2,4+2+4,4+2+6,4+4+2,6+2+2,6+2+4, 6+4+2,8+2+2

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According to traffic, we can make such type of configuration with 2 sectors: 2+4,2+6,2+8,2+2,4+4,6+6,4+2,4+6,4+8,6+2,6+4,8+2,8+4

According to traffic, we can make such type of configuration with 1 sector: 2, 4,6,8,10,12

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 According to Traffic/Coverage we can add 4th _sector.

Configuration we will make 2+2+4+4,4+4+2+2,4+2+2+4 OMC-R ACTIVITY:

According to configuration, the TRX, TX should be attached to respective cells. Also MAIO should be given accordingly (RXMOC,RLCHC)

For 4th _{sector addition, a new cell D be created like old cells. RF parameters}

should be given by RF planning.

3.3.3 Take the MO dump and RL dump process it (monthly). check the Co BCCH-BSIC cells, Missing Neighbours, Missing Measurement CGI, BCCHs ,MAIO, HSN, LAC etc.

MO DUMP MO COMMNDS: RXTCP:MOTY=RXETG; RXMOP:MOTY=RXETG; RXMOP:MOTY=RXETRX; RXMOP:MOTY=RXETX; RXMOP:MOTY=RXERX; RXMSP:MOTY=RXETRX; RXASP:MOTY=RXETG; RXTCP:MOTY=RXOTG; RXMOP:MOTY=RXOTG; RXMOP:MOTY=RXOCF; RXMOP:MOTY=RXOTF; RXMOP:MOTY=RXOCON;

44 RXMOP:MOTY=RXOTRX; RXMOP:MOTY=RXOTX; RXMOP:MOTY=RXORX; RXMSP:MOTY=RXOTRX; RXMDP:MOTY=RXOTRX; RXMFP:MOTY=RXOTRX; RXMFP:MOTY=RXOCF; RXAPP:MOTY=RXOTG; RXASP:MOTY=RXOTG; NTCOP:SNT=ALL; DTQUP:DIP=ALL; RL DUMP: RLTYP; RLLBP; RLDCP; RLLSP; RLOMP; RLVAP; RLCAP; RLVLP; RAEPP:ID=ALL; SAAEP:BLOCK=RQCD,SAE=522; SAAEP:BLOCK=RQCD,SAE=523; SAAEP:SAE=298; SAAEP:SAE=299; RLDEP:CELL=ALL; RLDEP:CELL=ALL,EXT; RLSTP:CELL=ALL; RLCFP:CELL=ALL; RLNRP:CELL=ALL; RLCPP:CELL=ALL; RLCPP:CELL=ALL,EXT; RLPCP:CELL=ALL; RLLHP:CELL=ALL; RLLHP:CELL=ALL,EXT; RLLOP:CELL=ALL; RLLOP:CELL=ALL,EXT; RLCXP:CELL=ALL; RLHPP:CELL=ALL; RLBCP:CELL=ALL; RLIHP:CELL=ALL; RLMFP:CELL=ALL; RLLUP:CELL=ALL; RLLPP:CELL=ALL;

45 RLLFP:CELL=ALL; RLLDP:CELL=ALL; RLSBP:CELL=ALL; RLSSP:CELL=ALL; RLOLP:CELL=ALL; RLSMP:CELL=ALL; RLHPP:CELL=ALL; RLIMP:CELL=ALL; RLLCP:CELL=ALL; RLCRP:CELL=ALL; RLACP:CELL=ALL; RLSLP:CELL=ALL; RLCDP:CELL=ALL; RLPBP:CELL=ALL; RLOLP:CELL=ALL; RLLLP:CELL=ALL; RLBDP:CELL=ALL; RLGSP:CELL=ALL; RLGRP:CELL=ALL; RLDRP:CELL=ALL; RRGBP; PROCEDURE:

COPY all MO commands-> paste at Command File of WIN Fiol-> Create Log file (Press F8)->Run all commands(Again Press F8)->close output of log file.

Process it through RL DUMP Processor S/W.

It will show all the information of h/w all BTSs like TG,CF,TRX,TX,DIP everything in a EXCEL file.

Similarly we can process al the RL commands. By which we get the cell parameters all BTSs like CGI, pwr, neighbour, hsn, maio everything in a EXCEL file.

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4 BSC

4.1 BSC Function

The BSC is connected to the MSC on one side and to the BTS on the other. The BSC performs the Radio Resource (RR) management for the cells under its control. It assigns and release frequencies and timeslots for all MSs in its own area. The BSC performs the inter-cell handover for MSs moving between BTS in its control. It also re-allocates frequencies to the BTSs in its area to meet locally heavy demands during peak hours or on special events. The BSC controls the power transmission of both BSSs and MSs in its area. The minimum power level for a mobile unit is broadcast over the BCCH. The BSC provides the time and frequency synchronization reference signals broadcast by its BTSs. The BSC also measures the time delay of received MS signals relative to the BTS clock. The BSC provides control of the BTSs and manages radio resources and radio parameters. A single BSC can control a large number of BTS.

The BSC functions are divided into the following sub-functions:

 Provision of signalling links to the MSC

 Signalling control of the BTSs and hence the Mobile Stations  Signalling control of the links with the MFS (what is MFS)  Switching of traffic between the MSC and the BTSs  Routing of traffic between the MFS and the BTSs  Provision of O&M facilities.

The basic functions of BSC are  Telecommunication functions,  Transmission functions,  O&M functions

 Telecommunication functions:

BTS are responsible to handle physical resources. Logical resources like Radio frequency management (GSM & GPRS) and TCH management is done by the BSC. Every half second BTS’s send radio measurements to the BSC. Those measurements are processed by the BSC which is going to take the handover decision in some cases.

Management of GSM radio frequency is also done by BSC. The frequency of various channels like Broadcast and Common control channels, signalling channels are handled by BSC. Radio measurement processing, In Call Modification handling is done by BSC.

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BSC also handle GSM & GPRS traffic channel resource management like:-  Establishes and releases radio resources

 Queues requests

 Selects TCH for handovers

4.2 BSC Hardware

Ericsson BSC is build up with AXE 810 architecture. It is more powerful, less space and power dissipating. The hardware components are:

1. GEM (Generic Ericsson Magazine)

2. Group Switch GS 890 (distributed, non-blocking) 3. CL 890 (new clock modules)

4. On board RP (RPI)

5. ET 155-1 (one board ET 155) 6. APG – 40

An important factor behind the AXE flexibility is the APZ Control System Architecture, which is a two-level architecture including both central and distributed control. It is an approach that ensures high reliability and efficient call handling.

APG Adjunct Processor Group

CP Central

Processor

EMG Extension Module Group EMG EMRPI Extension Module Regional Processor Integrated RPs Regional Processor... EMRPI RPB STR RP Bus Signal Terminal Remote

STR TCP/IP AP G Ethernet RPG RP RPP RPI RPG RPB IPN - CP Ether net

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CP & RP

The Central Processor, CP is duplicated, offering high hardware fault tolerance. In the event of a fault, the control may be swapped to the other side with a minimum or no impact on the traffic handling capability.

The Regional Processors, RPs, are used for routine repetitive processing and for processing intensive tasks such as the termination of the lower protocol layers. The most recent regional processors are open processing platforms, on which it is possible to run application software using industry-standard programming languages such as C or C++. The use of high-level languages also presents other opportunities such as substantial Time to Market gains through the incorporation of off-the-shelf standard software modules.

RPP is targeted to support data communication related telecommunication applications. RPP offers a range of open hardware interfaces, a range of software applications plus a complete development environment. It work as a PCU (Packet Control Unit)

The PCU is a node in the GSM network. It is designed to provide an interface between the circuit-switched GSM network and the packet-switched GSN nodes. These GSN nodes in turn provide an interface to public packet-switched networks.

The hardware consists of 1-7 RPPs and 2 no of EPSs which can be connected together using Ethernet i.e. IP. Each RPP can connect to the SGSN (via the Group Switch when FR is used). For GB over IP EPS card connects SGSN directly through the BSC internal IP Gateways . Each RPP card provides 64 circuits of 64kbps per circuit. If GB over Frame Relay is used 31circuits will be utilized for 2MB connectivity with SGSN and rest 33 circuits will be used for radio access. All the 64 circuits can also be used for radio access if GB over IP is used. In GB over IP configuration the EPS card provide up to 100 mbps bandwidth with SGSN through IP gateway and work in redundancy mode. In this case all the RPP resource will be utilized for radio access.

Inter Platform Network

An Ethernet based, 100 Mbps or 1 Gbps, Inter Platform Network, IPN, is ringing in an industry standard, high capacity interface into AXE.

Other Systems, A

P AP e.g. TSP, AXD 301

CP IPN

49

Generic Ericsson Magazine

Another far-reaching improvement is the GEM, a high-capacity, flexible, and scalable magazine (sub-rack) that anticipates future developments. GEM-based nodes will be smaller, dissipate less power, and have greater maximum capacity. Their implementation will dramatically improve the cost of ownership and cut time-to-customer for AXE.

A GEM can house

• two SCB-RPs, providing an Ethernet switch, control function, maintenance support, and power distribution;

• two switch boards (XDB), providing a 16 K plane duplicated group switch; • up to 22 device boards with 15 mm spacing, such as ET155, ECP, or TRA;

• pairs of DLEBs, providing multiplexing functionality for DL3 cable interfaces, placed in device slots; and

• CL890 clock modules placed in device slots. Transcoder

The Transcoder/Rate Adaptation (TRA) function in BSC/TRC performs transcoding of speech information and rate adaptation of data information. It also contains functions for Discontinuous Transmission (DTX). The capacity in number of channels per board for the different versions of TRA hardware is given below.

TRA HW

Version FR EFR HR AMR _FR AMR _HR

R5A 24 24 24

R5B 24 24 24 24 24

R6 without

TFO 24 per device group of any speech codec (n=1..8), 192 in total R6B 24 per device group of any speech codec (n=1..8), 192 in total R6 with TFO (Tandem Free Operation) 124 (16 per device group) 124 (16 per device group)

For R5 different codec cannot be mixed on the same board. Each TRA R6/R6B board consists of 8 device groups and each device group can be configured for any of the supported codec. The capacity for TRA R6 differs depending on if the device group is configured to support TFO, in that case a device group can handle 16 channels. Else and for TRA R6B the capacity is 24 channels per device group.

One TRA EM consists of one TRA board. The TRA R5 magazine includes (up to) 16 TRABs. TRA R6/R6B is housed in a GEM magazine where it can be mixed with other boards depending on the configuration. All TRA hardware versions can be mixed in the same speech codec pool. Presently we are using CSPB R2 board which work on R6B application.

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Note that, when there are several pools, it is normally the case that AMR, EFR or HR capable mobiles also support FR. In this case the traffic can be shared between the pools and thus not all of them need to be dimensioned for the same grade of service. This means that congestion in one pool, for example, the EFR pool, does not necessary imply congestion for a call, as another pool, e.g. the FR pool, can be used instead.

ET-155

The ET155-1 OC-3 is a single board 155 Mb/s, OC-3, Exchange Terminal supporting ANSI standards for SONET. The ET155-1 OC-3 together with the GEM concept of AXE offers very compact and scalable node solutions for cost efficient connections to the transport network. For the purposes of equipment and network protection, Automatic Protection Switching, APS 1+1, can be provided as an option. For Abis link E1 is required which can be extracted by connecting 2Mb MUX (OMS) with ET155-1.

OMS

OMS is a MUX which convert one TM to 63 E1. It is a separate equipment and not under AXE environment. For the maintenance of OMS its O&M software to be loaded in Laptop and by connecting the Laptop to OMS’s console the Card configuration and E1 configuration can be done. Sometimes, on power recycle, the E1 configuration of OMS gets corrupted. To rectify this we have to logging into OMS through console and through O&M command reconfiguration can be done.

APG 40

The APG40 is a platform for the AXE central processor IO functions (APIO) that were inherited from the IOGs. It is also a platform for billing (for example, FOS) and statistic data collecting (for instance, STS), storage, processing and output from the AXE switch. For example, the APG40 can be a platform for collecting data related to in-service performance from the central processor. It can also format that data for distribution to an operations management.

4.3 BSC Preventive Maintenance

Whenever visiting a BSC, check the following points to ensure that everything is in order:

Equipment related checks

Check for any fault in the unit or any other alarms

No visual damage to the equipment or site room is evident The equipement and the place should be kept clean and cleaning schedule should be maintained sincerely

It should be ensured that all external alarms are extended and are working properly

Environment

Air conditioners are functioning correctly. There is no leakage of air-conditioned air through door or window.

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Indoor light is working & Indoor emergency light is working

Battery / Power plant / DG

All modules of SMPS power plant are working properly and load is being shared by all.

Check back-up batteries for corrosion and leakage.

Check the run time of Engine Alternator and compare it with the manufacturers’ recommended service interval regarding the run time and ensure regular service.

The oil in the Engine Alternator should be checked with the dipstick to ensure its sufficient level and also its usefulness.

Earthing

It should be ensured that Earth resistance value has been measured once in every six months and the same is displayed. It should be less than 0.5 ohm.

Fire Safety Expiry date on Fire extinguisher and sufficiency of fire safety equipments.

Other The media connectivity record should be maintained in a database.

4.4 BSCMonitoring, Alert and Rectification Mechanism

 Faults are being continuously monitored on 24 X 7 by NOC / OMCR personnels.  As and when any fault occurs in the network it is indicated on OMCR monitor. 4.4.2 Fault Alert mechanism

 24X7 NOC / OMCR staff escalates the fault to the concerned persons/ field staff.

 Software based automatic alert system is put in place which informs the faults to the concerned staff through SMS

 The concerned officer identifies the fault reason like media problem / power supply problem / equipment related problem

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4.4.3 Fault Rectification Mechanism Reason of

Fault Action to be taken

Media The section is to be identified and concerned officer is being informed for furher rectification.

Power

 If the power supply is disconnected, it should be ensured tha Battery is taking load and if required DG set shoud be started.

 If there is problem of power plant module, it should be replaced. Equipement

related

 Hard reset should be given from the site Faulty cards should be replaced/ Jack-out-Jack-in.

 Faulty hardwares should be attended as per the procedure given under BSC healthcheck & Routine Maintenance

Enviorment (High

Temperature)

 Check Air condition working

4.5

BSC Health Check & Routine Maintenance.

4.5.1.1 Check Alarm Log: Command

ALLIP:ALCAT=APZ;

This command displays the all active alarm of control part. Command Output:-

A2/APZ "B25I18X0150_A.W" 163 151007 1842 RP FAULT

RP TYPE 165 RPG3A

This implies RP-165 is faulty. Then attend the RP fault as per RP handling procedure given latter on in this document.

4.5.1.2 Check the Processor Load Command

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Command Output:-

PROCESSOR LOAD DATA

INT PLOAD CALIM OFFDO OFFDI FTCHDO FTCHDI OFFMPH OFFMPL FTCHMPH FTCHMPL 1 3 72000 59 1 59 1 3 57 3 57 2 3 72000 45 11 45 11 1 9 1 9 3 3 72000 53 9 53 9 3 4 3 4 4 3 72000 60 9 60 9 5 9 5 9 5 3 72000 62 10 62 10 3 4 3 4 6 3 72000 54 8 54 8 4 12 4 12 7 2 72000 43 8 43 8 4 5 4 5 8 3 72000 55 8 55 8 9 12 9 12 9 3 72000 56 3 56 3 6 4 6 4

Processor load must be within limits and report if it exceeds 90. 4.5.1.3 Check the CP State

Command DPWSP; Sample Output:- CP STATE MAU SB SBSTATE NRM B WO

This implies Both CP are in working status with CP-A executive and CP-B in Standby state. If any of the CP is in wrong state then following commands may be used to rectify the same. 4.5.1.4 CP Diagnosis

REPCI;

This command initiates diagnosis of fault in CP. The command results in a printout CP DIAGNOSIS that contains list of suspected boards.

Command Output: CP DIAGNOSIS TESTRESULT Testresult FAULT TYPE Fault type

MAG PCB REPLACED REASON mag pcb [replaced reason]

54

If there is any hardware fault, the PCB name will be displayed under PCB with TESTRESULT as fault. Then replace the faulty board as per the output of following command.

4.5.1.5 Manual Intervention in CP Repair REMCI:MAG=mag, PCB=pcb;

Command Output:-

CP MANUAL INTERVENTION

INTERVATION PREPARATION SUCCESSFUL |ACTION MAG PCB NOTE |

|action |mag| |pcb| note |

The result printout CP MANUAL INTERVENTION indicates if replacement of the board is permitted or not, and give instructions how the replacement should be done.

4.5.1.6 Repair Check in CP

After PCB replacement as per previous command the CP repair is to be checked with the following command. RECCI; Command Output:- CP REPAIR SUCCESSFUL NOT SUCCESSFUL [RP: rp1 rp2 ]

If the TESTRESULT shows successful, the CP has been repaired successfully. Otherwise we have to act as per UNCESSFUL remark (rp-address faulty)

4.5.1.7 Check RP status EXRPP:RP=ALL:

Command Output:-

RP DATA

RP STATE TYPE TWIN STATE DS MAINT.STATE 32 WO RP4S1A 33 WO 248 IDLE 33 WO RP4S1A 32 WO 248 IDLE 34 WO RPPS1 IDLE 35 WO RPPS1 IDLE 36 WO RPPS1 IDLE 37 WO RPPS1 IDLE

55

All RPs should be in WO state. If any RP is in ABL status then attend the RP fault as per the following commands.

4.5.1.8 Blocking & De-blocking of RP BLRPI:RP=rp,forced;

BLRPE:RP=rp;

Then check the RP status using EXRPP command. If again the RP status becomes ABL then use the following command to repair the RP.

4.5.1.9 RP Diagnosis REPRI:RP=rp; Command Output: RP DIAGNOSIS TESTRESULT testresult RP EM PCB REPLACED REASON rp [em] pcb [replaced reason]

pcb [replaced reason]

If there is any hardware fault, the PCB name will be displayed under PCB with TESTRESULT as fault. Then replace the faulty board as per the output of following command.

4.5.1.10 Manual Intervention in RP Repair REMRI:RP=rp, PCB=pcb; Command Output:- RP MANUAL INTERVENTION |RP EM PCB ACTION | |rp |em| |pcb| action | |FAULT INTERRUPT | |fault type |

4.5.1.11 Repair Check in RP

After PCB replacement as per previous command the RP repair is to be checked with the following command.

56 RECRI:RP=rp; Command Output:- RP REPAIR RP EM TESTRESULT rp [em] testresult

If the TESTRESULT shows passed, the RP has been repaired successfully. Otherwise we have to again test the RP by REPRI command.

4.5.1.12 Check that the latest backup file are available in the system

CP backup contains all Exchange database including hardware installed and configured BTS / GB link etc. This data is most important for BSC and in emergency this need to be reloaded to the system. Hence we should check the proper backup regularly.

Command SYBFP: FILE;

Command Output:

SYSTEM BACKUP FILES FILE IO EXCHANGE RELFSW0 - B25I18X0150_A.W

SUBFILE TYPE OUTPUTTIME CURRENT COMMANDLOG R1 DSSMALL 151202 0201 YES - R2 DSSMALL 151201 0201 NO - R3 DSLARGE 151201 0201 YES 0002639 R4 DSLARGE 151202 0201 NO 0002640 R5 PS,RS 151105 0823 YES - FILE IO EXCHANGE RELFSW1 - B25I18X0150_A.W

SUBFILE TYPE OUTPUTTIME CURRENT COMMANDLOG R1 DSSMALL 151104 0201 NO - R2 DSSMALL 151105 0201 YES - R3 DSLARGE 151105 0201 NO 0002612 R4 DSLARGE 151104 0201 YES 0002611 R5 PS,RS 151006 0733 YES - FILE IO EXCHANGE RELFSW2 - B25I18X0150_A.W

57

SUBFILE TYPE OUTPUTTIME CURRENT COMMANDLOG R1 DSSMALL 151005 0201 NO - R2 DSSMALL 151006 0201 YES - R3 DSLARGE 151006 0201 NO 0002581 R4 DSLARGE 151005 0201 YES 0002580 R5 PS,RS 150904 1435 YES - END

The latest backup (yesterday date) file should be in RELFSW0 volume. If it is not up-to-date then backup has been halted. Then we will go for manual backup as per the following commands.

a. SYBUE; (to stop automatic backup)

b. SYBUP:FILE=RELFSW2; (to start cp backup in relfsw2 volume)

c. SYTUC; (to rotate latest backup from relfsw2 volume to relfsw0 volume) d. SYBUI:DISC; (to start automatic backup)

4.5.1.13 Check for any software file congestion

Command

DBTSP: Tab=SAACTIONS; Command Output:-

DATABASE TABLE

BLOCK TAB TABLE WRAPPED SAFTAB1 SAACTIONS YES

ACTNUM SAE BLOCK TYPE CNTRTYP CURRNI NEWNI 0 348 GLOBAL CONS2 512 528

NIE NIR STATUS NCONG 16 16 REG 4

This implies there is congestion in SAE-348 whose size to be increase from 512 to 528 using standard procedure as per Alex.

4.5.1.14 Check the status of the C7 Links

C7LTP: LS=ALL; Command Output:-

58

LS SPID SLC STATE INHIBST FCODE INFO 3-10386 ORMGSB1 00 ACTIVE

01 ACTIVE

All links should be active. If any link is not active then the E1 of corresponding link may be faulty. We have to check the E1 status by the DTSTP command. If E1 (dip) is ok, then the status of signalling terminal (ST) card is to be checked by the following commands.

C7LDP:LS=3-10386; CCITT7 LINK SET DATA LS SPID ASP SPID 3-10386 ORMGSB1

SLC ACL PARMG ST SDL SLI

0 A2 24 C7STAH-1&&-31 ORMGSB1-0 /C7STAH-1/RALT2-1 1 A2 24 C7STAH-33&&-63 ORMGSB1-1 /C7STAH-33/RALT2-4033 EXEMP:RP=ALL,EM=ALL;

EM DATA

RP TYPE EM EQM TWIN CNTRL PP STATE 258 RPPS1 0 C7STAH-0&&-31 PRIM WO

482 RPPS1 0 C7STAH-32&&-63 PRIM WO.

For problematic link, the state of the EM may be in ABL / CBL state. If it is in ABL state we can reset the card by BLEMI, BLEME command. If it is in CBL state the RP card to be reset by BLRPI, BLRPE command.

4.5.1.15 Check Group switch status

Command Output:-

DISTRIBUTED GROUP SWITCH STATE UNIT STATE BLSTATE VAR STATUS CLM-0 WO 11 MASTER

CLM-1 WO 11 SLAVE

59 XM-A-0-0 WO 1 XM-B-0-0 WO XM-A-0-1 WO 1 XM-B-0-1 WO XM-A-0-2 WO 1 XM-B-0-2 WO XM-A-0-3 WO 1 XM-B-0-3 WO XM-A-0-4 WO 1 XM-B-0-4 WO MUX34-A-0 WO 0 MUX34-B-0 WO MUX34-A-1 WO 0 MUX34-B-1 WO MUX34-A-8 WO 0 MUX34-B-8 WO MUX34-A-9 WO 0 MUX34-B-9 WO

All TSM/SPMs should be in WO status. If any Switch card is in ABL state then attend it with the following command.

GDBLI, GDTEI, GDBLE,

4.5.1.15.1 Check network synchronization data

GDCVP;

DISTRIBUTED GROUP SWITCH CLM CONTROL VALUE

CLM OSCILLATOR CONTRVALUE AVERAGEVALUE FAULTCASE CLM-0 0 33706 33706

1 34018 34052 CLM-1 0 31228 31290 1 33853 33886

The clock control value should be 32768 with deviation from 31000 to 34000. If the deviation is more it might be due to reference clock failure. Then we have to check the reference clock status and deviation through below command.

NSSTP; Command Output: CLOCK-REFERENCE STATE REF STATE BLS 0ETM2,MS-0 EX 1ETM2,MS-1 SB

One of the Clock reference state should be in EX condition. Otherwise, the corresponding TM status to be checked. We may check the SDIP status and error if any, in the RALT device. If TM is ok then reset clock with the following command:- NSBLI, NSTEI, NSBLE.

a. NSDAP;

Command Output:-