| Abstract: | In multi-channel systems such as multi-station packet radio networks or cellular radio, various user categories arise. In this paper, we propose that one portion of the users, named low-priority, each be assigned a specific channel for their transmissions, whereas another portion, named high-priority, may transmit through any of the channels via some channel selection policy. The main objective is to reduce delays of the high-priority users without imposing heavy penalties on the delays of the low-priority group. For the described system, we adopt a previously studied limited sensing random access algorithm and introduce two dynamic channel selection policies. We study the stability region and the delays induced by the system. The selection policies present the high-priority users with a significant delay advantage and induce fair utilization of the transmission channels, without requiring any knowledge about the system state by the users. One of the selection policies induces high system throughput at the expense of implementation complexity and increased delays for the low-priority users. The second policy is easier to implement but, although it does not penalize the delays of the low-priority users, it reduces the system thoughput. |
