190707542-06-GSM-R-Parameters

1 Nokia Siemens Networks NPO Trainings / GSM-R Workshop

For internal use

GSM-R Parameters GSM-R features

Links with additional information

Munich, August 2008

2 Nokia Siemens Networks NPO Trainings

For internal use

GSM-R Network Design

Nominal

Plan

Traffic

model

Coverage

levels

Link

budgets

Site

configuration

Frequency

plan

Neighboring

plan

Project

databases

(NSS, BSS)

Group Call Areas

plan

Train traffic

control data

Project

database

(IN)


For internal use

Agenda

-ASCI related parameters

- GSM-R features

- Where to find information


For internal use

ASCI Introduction

ASCI = Advanced Speech Call Items

ASCII =American Standard Code for Information Interchange

Voice Group Call Service VGCS / Voice Broadcast Service VBS

One VBS/VGCS call number combines all members of a certain group

For each VBS/VGCS call a service area composed out of a number of cells is assigned

Dialing the VBS/VGCS call number initializes the parallel set-up of connections into all cells of the assigned service area. All members of this group being in the service area will be paged to receive a notification of the ongoing VBS/VGCS call

Dependent on the call ID and priority members of the VBS/VGCS call can decide to join the call


For internal use

ASCI Introduction Notification channel NCH

Notification Channel NCH is used in order to notify ASCI subscribers of the VGCS/VBS call in each cell

These messages use the group identity and service area identity

NCH (belonging to CCCH ) shall be configured in all the cells where the ASCI service is enabled. This logical channel is mapped onto

contiguous blocks reserved for access grants

An ASCI MS in addition to monitor the paging blocks, monitors the notification channel.

The process of broadcasting messages on NCH helps to provide late entry facility ASCI MS who entry into the cell where ASCI call is ongoing is connected to the call


For internal use

The eMLPP service introduces a subscriber specific priority. The feature has two parts, precedence and preemption.

Precedence assigning a priority level to a point-to-point call, a group call or a broadcast call in combination with a fast call setup.

If the Air-interface is congested a low priority call could be preempted to free resources for a high priority connection.

Hardware failure

Shutdown due to O&M intervention normal calls are saved by handover procedure, ASCI calls are simply released

Preemption due to higher priority call

Enhanced multilevel precedence and preemption eMLPP

ASCI Introduction

Reasons for ASCI service termination


For internal use

ASCI Introduction Administration of VGCS & VBS

Group Call Reference -GCA +GID

-Dispatchers

-E.g 12345-299

Radio

cell C

Radio

cell A

Radio cell D

Radio cell E

Radio

cell B

Group Call Area -Cell A, B and C

-Service VGCS

-E.g 12345

Group ID -Given to the subscriber in the

HLR

-Stored on the SIM card of the

subscriber

-E.g 299


For internal use

Radio

cell C

GSM Infrastructure

Radio

cell A

Radio cell D

Radio cell E

Train is

delayed

Train is

delayed

Train is delayed

Radio

cell B

ASCI Introduction VBS Voice Broadcast Call

The Group Area is predefined

Train controller initiates a VBS call

in a Group Area

The speech is broadcasted to all

users in the area

A common downlink channel

to all listeners


For internal use

ASCI Introduction VGCS Voice Group Call Service

Radio

cell C

GSM Infrastructure

Radio

cell A

Radio cell D

Radio cell E

Train is

delayed

Train is

delayed

Radio

cell B

OKEY, No

problem

OKEY, No

problem

Train is delayed

The Group Area is predefined

Train controller initiates a VGCS

call in a Group Area

The speech is broadcasted to all

users

A common downlink channel

to all listeners

If a member requires the talk

function, a duplex

connection will be

established


For internal use

ASCI Introduction VGCS 1.5 and 1 Channel Model

Initial call by group member (identical for both models):

Dedicated connection to originator Before VGCS

0 7

0 7

0

7

0 7

UL

DL

0 7

0 7

Broadcast connection to listeners

Talker change In 1.5 Channel Model the dedicated channel has been assigned to a new Timeslot

UL

DL

0 7

0 7

0 7

0 7

In 1 Channel Model the talker may move from the dedicated channel to voice group call channel


For internal use

ASCI Related parameters

DB Name Object Range

(default)

Meaning

ASCISER BTS ENABLED,

DISABLED (DISABLED)

Enables or disables ASCI service on a cell

basis.

ASCIULR BTS ULRDISABLE

VBSENABLE

VGCSENABLE

VBS_VGCSENABLE

(ULRDISABLE)

The ASCI Uplink Reply parameter enables

or disables the uplink reply procedures for

both VGCS and VBS

TUPLREP BTS 5..60 s

(20)

This timer determines the period between

transmissions of the Uplink Free message in

the uplink reply procedure.

NOTFACCH BSC NO SUPP,

ALWAYS,

EQA, HIGHEQB, HIGHEQx, x=04 (NOSUPP)

Indicates for which mobile priorities the

NOTIFICATION FACCH messages are sent

on the FACCH belonging to the TCH seized

by one ASCI subscriber.

TGRANT BTS 1-254

unit 10ms

(4)

This timer determines the period in which

BTS waits for a correctly decoded message

from MS as an answer to the sent message

VGCS UL GRANT.


For internal use

ASCI Related parameters

DB Name Object Range

(default)

Meaning

VGRULF BTS 1-254

(1)

This parameter is used for the repetition of the

UPLINK FREE message during the Talker

Change procedure to inform all MS that UL is

free.

ASCIONE-

CHMDL

BSC TRUE,FALSE

(FALSE)

Determines whether the ASCI "one channel

model" is enabled or not.

ENPERNOTDE BTS TRUE, FALSE

(FALSE)

This attribute enables the repetition of

notifications on dedicated channels.

PNOFACCH BTS 1, 1.5 5 unit 0,5s

(5)

This attribute defines the duration of the

repetition period for the FACCH notification of a

given ASCI call.

ASCICIPH BTS TRUE, FALSE

(FALSE)

This parameter indicates whether the ciphering

for ASCI calls is enabled.


For internal use

Agenda

- ASCI related parameters

- GSM-R features

- Where to find information


For internal use

SF010330 HCS: Hierarchical Cell Structure

SF010403 ASCI : VGCS

SF010404 ASCI: VBS

SF010406 Queueing, Preemption and Directed retry for TCH

SF010424 ASCI Step 2

SF010967 ASCI: Notification for Late Entrants in railway emergency calls

SF010523: ASCI: Ciphering for Voice Group Call Services

ASCI: SMS for Group Calls

ASCI: eREC Sector ID notification

ASCI: Cell reselection-Introduction of new SI11

SF010573 Management of Standby TRX for BTS

SF010513 ASCI: Group Call Broadcast Point in BSS

SF010553 ASCI: Reactivation of VGCS/VBS channels after service unavailability

SF010570 ASCI: CS Data Transmission During Active VGCS

Existing/BR9

BR11.0 4Q/2010

GSM/EDGE BR Release Roadmap

BR10.0 10/2008

Dropped feature due to

standardization changes

New feature


For internal use

Ensuring the awareness of ongoing Group Calls for late entrants to increase security

ASCI: Notification for Late Entrants in REC

Advanced Speech Call Items (ASCI) subscribers are informed about an ongoing high priority group call e.g. emergency calls when entering a cell

in idle mode (cell re-selection) and

in dedicated mode incl. group transmit mode of Voice

Group Call Service (VGCS) or Voice Broadcast Service (VBS) handover

Now ASCI subscribers are also informed when they are in group receive mode already

Periodical sending on a common downlink channel of notifications on FACCH of all Group Calls in a cell indicate the presence of a high priority call

Feature ID(s): SF10967

BR9.0


For internal use

Increased security for Voice Group Call Services by introduction of ciphering

ASCI: Ciphering for Voice Group Call Services

In semi private networks run by authorities (police, ambulance, etc.) or certain companies (railways, etc.) VGCS are used to distribute information

Also sensitive information are exchanged via VGCS, which must be secured against eavesdropping.

The ciphering for Voice Group Call Services increased the security on the radio interface against secretly cut into to gain information

Ciphering for VGCS utilizing the security mechanisms is provided by A5/n

VGCS

Airport

Railway

Police


BR9.0


For internal use

Decreases core equipment and A-i/f transmission costs

ASCI: Group Call Broadcast Point in BSS

MSC BSC

BTS

MSC BSC

BTS

BR10.0


VGCS requires for each cell one DL channel to be assigned between MSC and BSC.

A lot of A and Asub resources would be required

The broadcast functionality is moved from the core network to the BSS, thereby significantly saving the A and Asub resources are achieved

Savings in the network between BSS and MSS

Leased line OPEX savings (mostly the case),

and

Reduced need for investments (CAPEX) in own infrastructure.


For internal use

Automatically resume of ASCI calls after outage of cells ensures stability of VGCS/VBS

Reactivation of VGCS/VBS after service unavailable

BR10.0


Currently VGCS/VBS channels of ongoing ASCI call are not re-activated during recovery after outage of cells (e.g. by the outage of related CU)

The Group/Broadcast Call Re-establishment feature supports to reactivate the service in the involved cells after outage as soon as the causes are overcome.

Already existing hand-shaking procedure at the A-Interface has been improved adding the Group Call Re-establishment -flag in the VGCS Feature Flags Information Element.

Automatic recovery of ASCI-service after service outage increased the availability of ASCI service


For internal use

ASCI: SMS for Group Calls

New market potential for the operator by SMS services for members of Voice Group Calls

BR11.0

Feature ID(s):

Enables the sending of SMS within members of a VGCS group in addition to sending of normal point-to-point SMS

Sending of SMS to active group calls dispatchers in a voice group call

listening subscribers

other initiators that are not part within this active VGCS

Receiving of SMS by the addressed active Group Call dispatchers of this active VGCS

listening subscribers of this active VGCS

talker of this active VGCS


For internal use

ASCI: eREC Sector ID Notification

Handling of concurrent Railway Emergency Calls allows drivers to focus on his own area

BR11.0

Feature ID(s):

The new enhanced Railway Emergency Call (eREC) enables the GSM-R operator to distribute emergency call to different areas in the same cell by indicating for which area the REC belongs to.

The BSC recognizes the eREC (290-298 - REC is notified with 299).

The BSC will then initiate a group call with number 299 + the last digit of the received GID and broadcasts in the Notification Channel (NCH)

Feature is cancelled

due to standardization

changes


For internal use

Where to find information

Sales feature description: https://sharenet-ims.inside.nokiasiemensnetworks.com/Open/367809903

BRxx database:

https://sharenet-ims.inside.nokiasiemensnetworks.com/Open/366549463

BR10.0 Operating documentation:

https://sharenet-ims.inside.nokiasiemensnetworks.com/Open/350267991, which includes:

Counters: pmsbscounter.pdf

KPI: kpi.pdf

Message flow: pmmf.pdf

Equipment configuration: omnbscequipconfb.pdf

BSC Network: omnbscnetb.pdf

BSC Transport: omnbsctransb.pdf

BSC Network Configuration: omnbscnetconfb.pdf

OMC RadioCommander: bsccml.pdf

22 Nokia Siemens Networks NPO Trainings / GSM-R Workshop

For internal use

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190707542-06-GSM-R-Parameters