6.5.2 Layer Functions

03.643GPPGeneral Packet Radio Service (GPRS)Overall description of the GPRS radio interfaceStage 2TS

The Physical Link layer is responsible for:

– Forward Error Correction (FEC) coding, allowing the detection and correction of transmitted code words and the indication of uncorrectable code words. The coding schemes are described in subclause 6.5.5.

– Interleaving of one Radio Block over four bursts in consecutive TDMA frames, as specified in GSM 05.03 [12.

– Procedures for detecting physical link congestion.

The Physical Link layer control functions include:

– Synchronisation procedures, including means for determining and adjusting the MS Timing Advance to correct for variances in propagation delay , GSM 05.10 [16;

– Monitoring and evaluation procedures for radio link signal quality;

– Cell (re-)selection procedures;

– Transmitter power control procedures; and

– Battery power conservation procedures, e.g. Discontinuous Reception (DRX) procedures.