CDMA Spread Spectrum Communication And Multiuser Detection Technology Application

Spread Spectrum communication became one of the communication ways with wide developing prosepect, and has being applied to military communication and civil communication extensively. Especially in recently about ten years, because CDMA communication rapidly is developing and the amount of user is increasing in striking speed, the capability of communication give prominence to fall. because capacity of channel is limited by interference, especially for the interference from the same channels and the adjacent channels. Therefore, multiuser detection technology has became a new hotspot in the research of mobile communication.First we set forth Spread Spectrum Communication system and its important guideline. We indicate three element above the Spread Spectrum Communication system. indicated makeup of Spread Spectrum Communication and the reason of its excellent capability。And indicated the knowledge of the Spread Spectrum Communication.We analysed the reason of produce on Pseudo Noise code though Spread Spectrum. At one time the thesis look back the part parallel interference cancellation detection, and update the Algorithm of the multiuser detection base on Kalman Algorithm and probabilistic algorithms for blind adaptive multiuser detection.After observing the correlative of Pseudo Noise code, we analyze the main cause of multi-access interference, and build the receiving model of multiuser system. In the thesis the optimum multiuser detectors with minimum probability of error and the near optimum detectors are intrduced, and then PIC multiuser detection is improved on.We indicated furthest multiuser detection technology and badest t multiuser detection technology, Educe it considern't the question of Pseudo Noise code on normal interference cancellation .decode interfix interference cancellation take out Pseudo Noise code produced Spread Spectrum. By joining the thinking of decorrelating detetion and PIC detection, we build the decorrelating parallel interference cancellation feed back detections and analyse its capability. especially for the interference from the same channels and the adjacent channels. Therefore, multiuser detection technology has became a new hotspot in the research of mobile communication. contemporary we looked back the part of parallel multiuser detection .At one time the thesis look back the part parallel interference cancellation detection, and update the Algorithm of the multiuser detection base on Kalman Algorithm and probabilistic algorithms for blind adaptive multiuser detection. At one time the thesis look back the part parallel interference cancellation detection, and update the Algorithm of the multiuser detection base on Kalman Algorithm and probabilistic algorithms for blind adaptive multiuser detection. we build the decorrelating parallel interference cancellation feed back detections and analyse its capability. especially for the interference from the same channels and the adjacent channels.Although we ware modelled on arithmetic to multi access interference multiuser detection. We don't considered it asynchronism. And it is a problem on realization to interference multiuser detection...