09_rn28199en20gla0_tcsm functions and settings.pdf

8/10/2019 09_RN28199EN20GLA0_TCSM Functions and settings.pdf

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TCSM Functions and Settings

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RN28199EN20GLA01 N okia Siemens Net works

TCSM Functions and SettingsRG20 (BSS)


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Objectives

After completing this learning element, the participant

should be able to: Creating Transcoding and Rate Adaptation Unit (TRAU)frame

Explain principle of Acoustic Echo Cancellation (AEC) andAutomatic Level Control (ALC)

Explain principle of Tandem Free Operation (TFO) andNoise Suppression (NS)

Interrogate and modify setting of TCSM3i

Refer to RG20 Documentation:

Functional area descriptions\ Transmission and transport\ TCSM3iFunctionalities\ Additional Features


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Example:FR TRAU frame

12345678

9101112131415161718192021222324252627282930313233

34353637383940

001

C81

D81

D23

1D38

1D53

1D68

1D83

1D98

1D113

1D128

1D143

1D158

1D173

1D188

1D203

1

D2181D233

1D248

1C18

00

C1C9D1D9D16D24

D31D39D46D54D61D69D76D84D91D99D106D114D121D129D136D144D151D159D166D174D181D189D195D204D211

D219D226D234D241D249D256C19

00

C2C10D2D10D17D25

D32D40D47D55D62D70D77D85D92

D100D107D115D122D130D137D145D152D160D167D175D182D189D196D205D212

D220D227D235D242D250D257C20

00

C3C11D3D11D18D26


D221D228D236D243D251D258C21

00

C4C12D4D12D19D27

D34D42D49D57D64D72D79D87D94


D222D229D237D244D252D259

T1

00

C5C13D5D13D20D28

D35D43D50D58D65D73D80D88D95


D223D230D238D245D253D260

T2

00

C6C14D6D14D21D29

D36D44D51D59D66D74D81D89D96


D224D231D239D246D254C16T3

00

C7C15D7D15D22D30


D225D232D240D247D255C17T4

1 2 3 4 5 6 7 8Octetno.

Bit number

One full rate TRAU frame consists of 260 bits speech/data information together with60 bits that are used for creating the TRAU frame structure (in-band signallingbetween the two DSPs in the BTS and in the TCSM).

Those 60 control bits contain information like frame alignment word, frame type,channel type, time alignment information, DTX on/off etc.


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Acoustic Echo Cancellation (AEC)

Echo No echo

Downlink

Uplink

Acousticecho

TCSM MGW

ECU

AEC

BTS BSC


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Automatic Level Control (ALC)

ALC is a speech enhancement feature, which automatically adjusts the

level of a speech signal towards a predefined target level, either amplifying

or attenuating the signal. In general, quiet signals are amplified and loud

signals are attenuated. This is done to compensate the varying signal levels in the network

resulting from various circumstances like different user equipment,

communication conditions, different speaker etc.

ALC configurations include: Constant mode: sets a fixed gain for a specific direction (UL/DL). In this

mode, the amplification/attenuation process is not affected at all by the input

speech signal itself, but solely by the predefined gain parameter.

Adaptive mode: automatically introduces gain/loss to the speech signal to

keep it at a predetermined target level.

Adaptive mode with noise compensation: In addition to the predefined target

level in adaptive mode, ALC module operation may also be controlled partly

by the noise level measured from the opposite direction. That is, target levelis adjusted depending on the noise level. When the noise level exceeds a

certain threshold, the target level starts to increase. Noise compensation

improves intelligibility when the user is in a high noise environment.


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Tandem Free Operation (TFO)

TFO in use8 or 16 kbits/s

BSS

TRAU

MGW

DecodingDecoding

Encoding

A side B side

BSS

TRAU

MGW

EncodingDecoding

Decoding

MSbMSa

TFO not in use64 kbits/s

PLMNPLMN

Tandem Free Operation

In mobile-to-mobile (MS-MS) calls the so-called Tandem Connection between twoTRAUs performs unnecessary speech encoding and decoding which decreasesspeech quality.

The Tandem Free Operation feature increases speech quality by preventing theunnecessary encoding and decoding.


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Noise Suppression

When activated, the Noise Suppression (NS) algorithm processes the

uplink and/or downlink speech samples to reduce the background noise

level during speech calls

Background noise is efficiently reduced in both directions

Reduced noise

TCSM2

NS

BTS BSC MSC

NS

BSS

Noise Reduced noise

Noise

Noise level is reduced without attenuation of speech signal.


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Local and remote operation of the TCSM 3i

BSCTCSM3i

TR3

ET ET

Ater

OMU

TSL 1

TC-LAPD

Functions related to operation and maintenance can be carried out:

by a remote session from the BSC or the OMC using the TC-LAPDin TSL 11,2bit

by using a local terminal with the following line parameter settings:

Bit rate: 9600 bit/s or 19200 bit/s

Data bits: 7

Parity: even

Stop bits: 1

Note:

For local session, connect your PC or VDU to the front panelof TR3. The TR3 features a RS232 interface and a RJ 45

connector. The cable used depends on your terminal.


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RN28199EN20GLA01 0 N okia Si emen s Networks

either/or

USERNAME> EXPERT

PASSWORD> SYSTEM

ZR?C

DISPLAY CHANNEL CONFIGURATIONZRC:PCM INDEX;

PCM INDEX BYTE 1..7TIME SLOT BYTE 1..24 (ANSI); 1..31 (ETSI)PARAMETER BYTE 1..11

1 = THROUGH CONNECTION2 = DOWNLINK DTX3 = LOOP TEST 04 = LOOP TEST 15 = CHANNEL STATE6 = TIME ALIGNMENT7 = FIXED GAIN ADJUSTMENT8 = ADAPTIVE GAIN ADJUSTMENT

10 = ACOUSTIC ECHO CANCELLATION PARAMETERS11 = TANDEM FREE OPERATION PARAMETERS

TC-MML Command Syntax 1

ZRC:1:1;

ZRC:1,15;

Refer to RG20 Documentation:

Reference\ Commands\ Service terminal commands\ TCSM3icommands


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TC-MML Command Syntax 2

ZE?C

E1 FUNCTIONAL MODES MODIFICATIONZEC:PCM INDEX:FUNCTIONAL MODE,FRAME ALIGNMENT MODE,USE OF SA-BITS;

PCM INDEX BYTE 0..7 /CHAR_3 ALL = ALL PCM LINES

FUNCTIONAL MODE CHAR_4NORM ... NORMAL MODESATR ... THROUGH CONNECTION OF SA-BITSV11M ... V.11 MODETRSP ... TRANSPARENT MODE

FRAME ALIGNMENT MODE STRDBLF ... DOUBLE FRAME MODECRC4 ... CRC MODEPARAMETER IS NOT GIVEN IF FUNCTIONALMODE IS TRSP

USE OF SA BITS STRB56 .... BITS 5 AND 6 IN Q.1 USEB5678 .. BITS 5,6,7 AND 8 IN Q.1 USEALLOWED AND OBLIGATORY IF FUNCTIONAL

MODE IS V11M

ZEC:1:NORM,DBLF;ZEC:ALL:NORM,CRC4;


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Interrogate TCSM settings

Transcoder equipment ZGT

Software in TR3 ZGI:TR3;

FPGA ZGI:FPGA;

DSP ZGI:DSP;

ET ZGI:ET;

PCM Lines / Types ZRD

Through Connections ZRC

Monitor A-Interface circuits ZRM

Transcoder functions(TFO, AEC, ALC,...) ZRC


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Exercises: Interrogate/modify settings of TCSM3i

Exercise: Interrogate and modify transcoder settings. Duration: approx. 30min

You are working on TSCM.

Start a remote or a local session to your TCSM!

___________________________________________________________________________

What kind of TCSM is this (Cartridge Master, Cabinet Head Master, )?

___________________________________________________________________________

How many A-IF PCMs are configured?

___________________________________________________________________________

How are they used (HR/FR/data)?

___________________________________________________________________________

Is ALC used?

___________________________________________________________________________

Switch all available additional features (AEC, ALC, TFO, NS) on!

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

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09_rn28199en20gla0_tcsm functions and settings.pdf

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