Effect of wireless link characteristics on packet-level QoS inCDMA/CSMA networks

摘要

In this paper, we analyze the effect of wireless linkncharacteristics on throughput, packet delay, and packet loss rate inncode-division multiple-access (CDMA) networks using carrier-sensenmultiple-access (CSMA) protocols. Although CSMA protocols are beingnextensively considered for applications in wireless networks, there isnno comprehensive analysis of the effect of the link characteristics onnpacket level QoS. In our paper, link parameters are incorporated intonthe analysis through the probability of correct channel sensing, thenprobability of packet correct demodulation, and the channel fading rate.nAlthough the imperfect channel sensing degrades the system performance,nthe analysis demonstrates that the CSMA system outperforms ALOHA even ifnthe probability of incorrect channel sensing is higher than 10-1n. A number of numerical results quantitatively illustrates thenimpact of the channel fading rate and spatial correlation of the fadingnon packet level QoS. These results can be used for practical networkndesign