Unified fast packet scheduling method considering fluctuation in frequency domain in forward link for OFCDM broadband packet wireless access

This paper presents the effect of a unified packet scheduling method considering the delay requirement of each traffic data stream, the channel conditions including the distance-dependent path loss, lognormal shadowing, the instantaneous multipath fading and the packet types in hybrid ARQ in the MAC layer when the entire allocated 100-MHz broadband bandwidth is segmented into multiple blocks in the forward link orthogonal frequency and code division multiplexing (OFCDM) wireless access in frequency-selective Rayleigh fading channels. Computer simulation results show that in a model where real-time (RT) traffic and non-real-time (NRT) traffic coexist, the outage probability of RT traffic users is reduced according to the increase in the number of frequency blocks owing to the increasing multiuser diversity effect when RT traffic accounts for up to 50%. Nevertheless, we clarify that the effect of block-wised scheduling on the enhancement of the achievable throughput of NRT traffic is small because the transmission time interval at each frequency block is assigned with high priority to RT traffic users with strict delay requirements, which results in a reduced multiuser diversity effect on NRT traffic users.