Combined CCMA/CDMA: Practical Applications for Communication Systems

One of the key challenges facing broadband nomadic/mobile wireless communications is to develop advanced wireless access technologies to achieve high-speed and high-quality transmission in severe fading channels with high frequency utilization efficiency. Both Collaborative Coding Multiple Access (CCMA) and Code Division Multiple Access (CDMA) techniques permit efficient simultaneous transmission by several users sharing a common channel, without subdivision in time or frequency. The main research focus of this proposal is to provide a practical design for a combined CCMA/CDMA scheme that will exploit the individual merits and mitigate individual limitations. So far research has been focused in conceptual feasibility studies with little or no practical implementation considerations. It is intended that the outcome of the proposed research will provide a more powerful multiple-access capability and a better performance by the introduction of iterative decoding. Thus the group will benefit from the visiting researcher's expertise in CCMA and CDMA schemes while building on and strengthening our expertise in low complexity iterative decoding techniques, leading to a significant breakthrough in practical multiple-access techniques through maximizing the number of users per channel and increasing the bandwidth efficiency in a practical manner.