Uplink and Downlink Communications Qualities in CDMA Cellular Systems Considering Effects of Traffic Distribution

This paper describes the effects of traffic distributions on uplink and downlink communications qualities in CDMA cellular systems. Many researches have been done from the viewpoint of the system capacity under ideal conditions in both uplink and downlink. However, there are few studies regarding traffic distributions that concurrently affect the uplink and downlink quality. The characteristics in both links are different even in a spatially uniform traffic distribution because the system structures are not symmetric between both links. When non-uniform radio environments are assumed, both link qualities become very different from each other. It is therefore important to design systems in consideration of link-specific characteristics in whole service area. This paper clarifies the difference in both link characteristics in CDMA systems regarding traffic distributions. key words: CDMA cellular system, traffic distribution, communications quality, uplink/downlink