TY - GEN
T1 - An iterative multiuser detection for LDPC coded FFH/MFSK systems
AU - Su, Szu-Lin
AU - Tsai, Her Chang
AU - Shen, Ye Shun
PY - 2007/12/1
Y1 - 2007/12/1
N2 - A turbo principle based iterative multiuser detection is proposed to reduce the BER in LDPC coded FFH/MFSK MA systems. First, a three-level hard-limiter on each chip with maximum-likelihood decision is made to avoid soft output ambiguity. Secondly, the reliable information from channel decoder is applied to aide multiuser interference reduction. When the soft reliability information of coded bit exceeds a predefined threshold, these code bits are defined as reliable bits. A symbol is reliable when all its bit vectors are reliable. As iteration proceeds, the number of reliable users is counted which will change the detection probability of the estimated symbol. Numerical results show that three-level hard-limited systems outperform two-level systems and the systems with modified soft outputs of multiuser detection have better performance than that of conventional iterative decoding systems.
AB - A turbo principle based iterative multiuser detection is proposed to reduce the BER in LDPC coded FFH/MFSK MA systems. First, a three-level hard-limiter on each chip with maximum-likelihood decision is made to avoid soft output ambiguity. Secondly, the reliable information from channel decoder is applied to aide multiuser interference reduction. When the soft reliability information of coded bit exceeds a predefined threshold, these code bits are defined as reliable bits. A symbol is reliable when all its bit vectors are reliable. As iteration proceeds, the number of reliable users is counted which will change the detection probability of the estimated symbol. Numerical results show that three-level hard-limited systems outperform two-level systems and the systems with modified soft outputs of multiuser detection have better performance than that of conventional iterative decoding systems.
UR - http://www.scopus.com/inward/record.url?scp=50249169833&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=50249169833&partnerID=8YFLogxK
U2 - 10.1109/ISTMWC.2007.4299164
DO - 10.1109/ISTMWC.2007.4299164
M3 - Conference contribution
AN - SCOPUS:50249169833
SN - 1424416620
SN - 9781424416622
T3 - 2007 16th IST Mobile and Wireless Communications Summit
BT - 2007 16th IST Mobile and Wireless Communications Summit
T2 - 2007 16th IST Mobile and Wireless Communications Summit
Y2 - 1 July 2007 through 5 July 2007
ER -