Title :
Interference cancellation for a high data rate user in coded CDMA systems
Author_Institution :
Inst. for Commun. Eng., Tech. Univ. Munchen, Germany
Abstract :
In CDMA systems combining several traffic channels leads to a multi-code (MC) CDMA system offering higher user data rates without increasing the system bandwidth. Due to imperfect spreading sequences, the transmission quality degrades in case of multipath propagation. The additional noise power caused by co-channel interference increases linearly with the number of traffic channels. In this paper, we demonstrate how to reduce this noise by cancelling out the co-channel interference in an iterative way using soft values of the decoded bits. The gain depends on the operating point of the coded system. Simulation results for turbo codes and convolutional codes are close to the results for an AWGN channel
Keywords :
channel coding; cochannel interference; code division multiple access; convolutional codes; interference suppression; iterative methods; land mobile radio; multipath channels; spread spectrum communication; AWGN channel; coded CDMA systems; convolutional codes; decoded bits; gain; high data rate user; imperfect spreading sequences; interference cancellation; iterative method; multi-code CDMA system; multipath propagation; noise power; traffic channels; transmission quality; turbo codes; Additive white noise; Bandwidth; Degradation; Gaussian noise; Interchannel interference; Interference cancellation; Multiaccess communication; Noise cancellation; Noise reduction; Traffic control;
Conference_Titel :
Communications, 1998. ICC 98. Conference Record. 1998 IEEE International Conference on
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-4788-9
DOI :
10.1109/ICC.1998.685102
