BTS MAINTENANCE

1.Hardware system

2.Typical case

1.System Position and Role in MobileNetwork

• In a GSM/GPRS network, ZXG10 B8018 is the radio transceiver for GSM BSS. BSC controls BTS, and one BTS serves a certain cell or several cells.

• Abis interface connects BTS to BSC. It helps BSC to manage radio resources, and achieve radio transmission with MS and relevant control functions through Um interface.

Rack structure

Signal flow

CSBCMB

DTRU（0~2）

B8018机柜

DTRU（3~5） DTRU（6~8）

LAYER 1 LAYER 2 LAYER 3

AEM AEM AEM

天馈

BSCEIB

Module function

Panel and indicator of CMB

CMB

PWR RUN SYN CLK MST STA M/S RST FPWR

LED Color Name Meaning Working Mode

1 Green/Red PWR Power LED Green ON: Normal Red ON: Alarm OFF: Power off or other reasons

2 Green RUN Running LED Green flashing at 4 Hz: Boot is running Green flash at 1 Hz: Application is running Others: System is abnormal

3 Green/Red SYNClock synchronization

mode LED

Green ON: Synchronization clock of the Abis interface network Green flashing at 1 Hz: Synchronization clock of the SDH network Red flashing at 1 Hz: E1 frame out-of-sync alarm Red ON: E1 line is broken or not connected OFF: Free running

4 Green/Red CLK Clock LED Green ON: Network synchronization is locked Green flashing at 1 Hz: Locking the phase Red ON: Clock fault

5 Green MST Active/Standby LED Green ON: Active state Green OFF: Standby state

6 Green/Red STA Status LED

OFF: Running normally Green flashing at 1 Hz: System initialization Green flashing at 4 Hz: software loading Red flashing at 1 Hz: LAPD link disconnection Red flashing at 4 Hz: HDLC link disconnection . Red ON: Other alarms (such as temperature, clock and frame

number alarms)

Panel and indicators of CDU

LED Position

Color Name Meaning Working Mode

1 Green FPOForward power output LED

ON: NormalOFF: Abnormal

2 Red SWR1VSWR level-1 alarm LED

ON: There is an alarmOFF: There is no alarm

3 Red SWR2VSWR level-2 alarm LED

ON: There is an alarmOFF: There is no alarm

4 Green PWR LNA power supply LEDON: NormalOFF: Abnormal

5 Red LNA LNA alarm LEDON: There is an alarmOFF: There is no alarm

DTRU PANEL INDICATORS

DTRU PANEL INDICATORS

The ID switch14 13 345678910111215 012

BTS_TYPE BTS_NOSLAVE1_

PORTSLAVE2_

PORTSATE ABIS_PORT ABIS_TS

• BTS_TYPE– 1100: B8018– 1101: B8112– 1110: M8202– 1111: M8204

• BTS_NO– No. of the cabinet of the same

site – 00: Basic cabinet– 01: Extended cabinet 1– 10: Extended cabinet 2

SLAVE1_PORT

The E1 port of the basic cabinet to

connect extended cabinet 1

00: Port E of the basic cabinet

01: Port F of the basic cabinet

10: Port G of the basic cabinet

11: Port H of the basic cabinet

SLAVE2_PORT

The E1 port of the basic cabinet to

connect extended cabinet 2

00: Port E of the basic cabinet

01: Port F of the basic cabinet

10: Port G of the basic cabinet

11: Port H of the basic cabinet

SATE

Whether to use the satellite

Abis link or not

0: Common Abis

1: Satellite Abis

ABIS_PORT

O&M port number

00: Port A

01: Port B

10: Port C

11: Port D

ABIS_TS

The O&M LAPD timeslot on

the Abis interface

000: TS16

001: TS31

010: TS30

011: TS29

100: TS28

101: TS27

110: TS26

111: TS25

CMB

S10 dip switch show as the table bellow

EIB

S2

S4

S6

S5

EIB

E1 color code

1 Green red 1 E1AIN+ The first E1 input 14 Green red 2 E1AIN-8 Blue red 1 E1AOUT+ The first E1 output 20 Blue red 2 E1AOUT-2 Green black 1 E1BIN+ The second E1 input 15 Green black 2 E1BIN-9 Blue black 1 E1BOUT+ The second E1 output 21 Blue black 2 E1BOUT-

Indoor alarm color code

1. white blue-- 12. Blac blue-- -03. white orange-04. black orange-05. green white--06. black green---07. white brown-08. black brown--09. blue red-0----010.red orange---0

HDLC link b/w CMB and FUC is broken.

Reason.1-The mismatch b/w the logical and physical configuration.

Reason.2-The DTRU power may be off.Reason.3-The connection B/w CDU and DTRU is

not proper.Reason.4-DTRU harware problem.Reason.5-CMB card have problem.

Lapd broken

Reason.1-The E1 is not conneted properly to e1 port .

Reason.2-The Dip Switch is not proper.Reason.3-There loop some where b/w site and

BSC.Reason.4-EIB is not working properly.Reason.5-particular PCM is faulty.Reason.6-configration is not proper in BSC .

Cell interruption alarm

Reason.1-the BCCH trx is offReason.2-DTRU is not available on the bcch trx.Reason.3-DTRU is not properly connected.

Cascading of sites

For the cascading of two sites we need to follow these steps.

1.Connect the E1 cable at port 1 on the top of bts for the master sites intigration.

2.As master site is on air use another E1 cable to connect the port 2 of the bts.

3.Loop back the first e1 of port 2 and check the status of upper CMB synch and clk status,if is green then its ok

VSWR alarm

Voltage standing wave ratio3.0>VSWR>1.5 VSWR1 alarmVSWR>3.0 VSWR2 alarm sitemaster to test the value of the VSWRReason.1-CDU problemReason.2-AEM problemReason.3-cable connection problem

continue• 4.The first E1 of port 2 connets to the transmission

medium for the slave site.• 5.connect the e1 at slave site at port 1.• 6.check the id port dip set and that should be

according to OAM timeslot 30 or 31.the mastes bts use 16 OAM time slot.

dip config- 16-000 30-010 31-001 These we set on S1 of id port and dip switch no is 0,1,2.

THANK YOU！