Two-stage dynamic uplink channel and slot assignment for GPRS

Abstract

General Packet Radio Service (GPRS) uses a two-stage mechanism to allocate uplink radio resource to Mobile Stations (MSs). In stage-1, the Base Station (BS) assigns several Packet Data CHannels (PDCHs) to an MS. Furthermore, a PDCH may be assigned to multiple MSs. In stage-2, therefore, the BS selects one of the multiplexed MSs in a PDCH to use the radio resource. In this work, maintaining a load balance between PDCHs in stage-1 is examined and several selection schemes to lower the mis-selection rate in stage-2 are proposed. From our simulation results, the cost deduced from the poor load balancing and selection schemes render a lower system throughput and a non-negligible increase In packet queuing delay. Among the various stage-2 selection policies, Round Robin with Linearly-Accumulated Adjustment (RRLAA) has the lowest mis-selection rate and outperforms the one without any heuristic up to 50%.