Radio Resources Operating Modes Definitions (Class B assumed)
• Class B Mobile is able to handle CS and PS Traffic but not at the same time
• Packet Switching Modes
– Idle (TBF not established)
– Transfer (TBF exists on one or more radio channels)
• Circuit Switching Modes
– Idle (no RR connection)
– Dedicated (RR exists)
Different MS behavior with Packet BCCH
Without allocated PBCCH
The GPRS MS listen to the GSM BCCH and PCH
•The GPRS MS will use the GSM CS PCH, RACH and AGCH
With allocated PBCCH
The GPRS MS reads SI on BCCH to find PBCCH
•Now the GPRS MS only listens on PBCCH and PPCH
•GPRS dedicated Packet System Information sent on PBCCH
•The PPCH, PRACH and PAGCH are used
The PBCCH timeslot must be a dedicated PDCH in R8.
GPRS Cell (Re-) Selection – No PBCCH used (III)
GPRS MS re-selects a new cell if any of the following criteria is satisfied:
• C1 for the serving cell falls below 0 for a 5 seconds
• C2 of non-serving cell exceeds C2 value of the serving cell for the period of 5 seconds.
• Serving cell becomes barred
• MS has unsuccessfully tried to access network the allowed number of times
• MS dettects a downlink signalling failure
GPRS Cell (Re-) Selection –PBCCH used
GPRS MS re-selects a new cell if any of the following criteria is satisfied:
• C1 for the serving cell falls below 0
• The best non-serving cell does have the highest value of C32 among:
– All cells with the highest priority fulfilling C31 criterion
– All cells, if no cells fulfill C31 criterion
• Serving cell becomes barred
• MS has unsuccessfully tried to access network the allowed number of times
• MS dettects a downlink signalling failure
