Enhancing the Performance of IDMA System by Irregular LDPC Codes
A method to enhance the performance of IDMA system by means of irregular LDPC codes was studied. Interleavers were used as signature character for user identification and iterative turbo detection and decoding approach was employed with reduced complexity. Gaussian approximation was applied to approximate the message probability density function on factor graph with multiple users. Iterative message update formulas on factor graph were derived. Degree profiles were obtained by using the iterative formula. Simulation result shows that the performance of irregular LDPC-Coded IDMA system is better than that of (3,6) regular LDPC-Coded IDMA system in terms of BER and performance gain about 0.6dB is achieved at BER 10-5 with 8 users for AWGN multiple access channel.
Gaussian approximation MAC LDPC IDMA Degree profiles
Jingxi Zhang Zhisong Bie Weiling Wu
Key Lab of Universal Wireless Communications, Ministry of Education, Beijing University of Posts and Key Lab of Universal Wireless Communications, Ministry of Education, Beijing University of Posts and
国际会议
北京
英文
113-116
2010-09-26（万方平台首次上网日期，不代表论文的发表时间）