SDCCH

-
SDCCH : Required number of SDCCH/8.

SDCCH are used for
Call set up
 location updating
 SMS are using the SDCCH channel.

The system supports four types of combination for SDCCH channels

SDCCH/4: The SDCCH is combined with the BCCH in time slot 0 on the BCCH carrier. This SDCCH configuration provides 4 subchannels for signalling. Only one SDCCH/4 can be defined for each cell. (BCCHTYPE = COMB).

SDCCH/4 including CBCH: One subchannel is replaced by a CBCH. This SDCCH/4 configuration provides 3 subchannels for signalling and one for transmission of 47SMSCB messages. (BCCHTYPE = COMBC).

SDCCH/8: This SDCCH configuration provides 8 subchannels for signalling (BCCHTYPE = NCOMB, CBCH = NO).

SDCCH/8 including CBCH: One subchannel is replaced by a CBCH. This SDCCH/8 configuration provides 7 subchannels for signalling and one for transmission of SMSCB messages (BCCHTYPE = NCOMB, CBCH =
YES).

Up to 32 SDCCH/8 can be specified per cell. This number is reduced by one if an SDCCH/4 is defined for the cell.
ave any type of combined BCCH and SDCCH/4.

The BCCH is always allocated to time slot number 0 (TN0) in the defined  ARFCN.
The CBCH is used for transmission of the messages when the function Short Messages Service Cell Broadcast (SMSCB) is activated in the cell. SMSCB enables the operator to submit short messages for broadcasting to a specific area within the PLMN.


Popular posts from this blog

SCFT - Single Cell Function test

-
Single Cell Function test SCFT is for verifying whether individual BTS works well or not, by making a single cell function test of BTS hardware and software. Essential items to be tested are as follows: 1) BTS Transmitter Output Measurement Test 2) Initial parameter establishment (Pilot PN/System ID/Site ID/Frequency, Neighbor List) 3) Call Origination and Termination Test 4) Softer Handoff Test/Antenna installation check (Direction, Tilt, Transmission Line) 5) Single Cell Coverage Test 6) Noise Floor Test 7) Parameter check.
Read more

Troubleshooting for GSM KPIs (SD Block & SD Drop)

-
KPIs to be monitored: ·             SD Blocking ·             SD Drop SDCCH Channel: ·    SDCCH channel is a dedicated channel which is using for LAC updation, Call Setup, SMS in Ideal mode. It works in UL & DL SD Blocking: ·    SD Blocking means that you are not getting SD resource for the call origination. When MS connects with Network then RACH and AGCH are provided. After AGCH, SDCCH is provided but if SDCCH is not provided at this time due to some problem or due to unavailable of SD by BSC. KPI Formula in Ericsson: ·             SDCCH CONGESTION = (CCONGS / CCALLS) * 100 ·             CCONGS - Congestion counter. ·  ...
Read more

PS core network

-
Image
The PS core network consists of two parts, the traditional General Packet Radio Service (GPRS) core network and the new Evolved Packet System (EPS) core network. The PS core network connects mobile subscribers to Packet Data Networks (PDNs) such as the Internet, corporate networks or operator services networks.  a functional overview of the PS core network. Logical entities and interfaces are shown in black and form a 2G/3G network, while the blue boxes and lines in Figure  show the LTE/EPC related parts. The LTE/EPC network can be regarded as an extension and evolution of existing 2G/3G networks. From a node implementation perspective, there is no strict border between the two networks. The corresponding logical entities of GPRS and EPS networks can be deployed concurrently in Ericsson PS core nodes, such as the SGSN-MME and EPG; these are marked in red. In addition, Ericsson GPRS nodes can be upgraded with EPC functionality by software only. Network evolution i...
Read more