Research On Joint Detection For TD-SCDMA Based On Independent Component Analysis

The capacity and performance of a code division multiple access (CMDA) system is essentially dominated by multiple access interference (MAI) and inter symbol interference (ISI). Therefore, the suppression and cancellation of MAI and ISI is a critical issue in the CDMA system.In TD-SCDMA, we use Joint Detection (JD) to eliminate MAI and ISI. Joint detection employs equalization technique, which regards the interference of other users as useful signals, and takes full advantage of the spread code, range, timing and delay of all users. Accordingly, it can eliminate MAI largely, expand the capacity of system, alleviate the requirement of power control and weaken the near-far effect.Theoretically, joint detection can completely eliminate the interference, but there exists some limitations of joint detection. For example, it can do nothing with the inter-cell interference; its precision of detection is affected by channel estimation; what's worse is that its computation complexity does not increase linearly with the number of channels. In order to improve the performance of JD, we present an algorithm called ICA-based JD based on researching the ICA theory and algorithm and ICA-based multi-user detection in DS-CDMA system, and then we apply it to the receiver of the uplink of TD-SCDMA system. This...