Comparison of radio capture models and their effect on wireless LAN protocols

Abstract

We examine the effect of radio capture on the performance of radio frequency wireless Local Area Networks (LANs). In many wireless LANs, multiple remote stations may simultaneously attempt to transmit data packets. Due to the capture effect, differences in received power levels can result in the successful reception of a packet in the presence of contending transmissions. We compare several types of radio capture models and investigate their effects on the slotted Aloha protocol, which is a component protocol of more complex multiple access protocols that are used in wireless LANs. Specifically, we analyze a vulnerability circle capture model as well as a more detailed model that includes the cumulative effect of the interference power generated by multiple contending remote stations. The effects of Rayleigh fading, shadowing, and different spatial distributions of remote stations are also considered.