A channel access protocol for embedding CSMA on spread-spectrum packet radio networks

The application of CSMA (carrier-sense multiaccess) in a spread-spectrum packet radio network using a receiver-based code unique to each terminal is proposed and studied. The technique is realized by two protocols, namely, the R-base/CSMA and the R-base/CSMA-BT (Busy Tone) code, which are presented and analyzed, assuming a single-hop network, asynchronous transmission, Poisson arrivals, and exponentially distributed packet lengths. The authors also consider the delay capture properties of speed-spectrum waveforms. The network is modeled as a continuous-time two component-state Markov chain. The R-base/CSMA-BT code protocol has also been examined under zero propagation delay since it becomes collision-free in this case. Throughput versus the traffic rate characteristics have been obtained for both protocols with several number of users and at different propagation delays.<>