THROUGHPUT ENHANCEMENT OF DIRECT-SEQUENCE SPREAD-SPECTRUM PACKET RADIO NETWORKS BY ADAPTIVE POWER-CONTROL

This paper investigates the performance of direct-sequence spread-spec trum packet radio networks in the presence of the near/far problem. It is found that the maximum throughput of the network suffers degradati on due to the near/far problem. However, analysis also shows that, und er high traffic conditions, a network with the near/far problem delive rs higher throughput than another without the near/far problem. This s uggests that the direct-sequence spread-spectrum packet radio network with the near/far problem retains stability for heavier traffic condit ions. Following these findings, a new adaptive power control scheme is suggested to enhance network throughput under both low and heavy traf fic conditions. The mean and variance of the packet delay are derived and network stability and deadlock avoidance issues are discussed. The impact of channel fading on the network behavior is also studied in t his paper.