Bandwidth-constrained signature waveforms and Walsh signal space receivers for synchronous CDMA systems
Tóm tắt
Synchronous CDMA systems whose transmission bandwidth is quantified through the fractional out-of-band energy (FOBE) constraint are considered. Either a conventional matched filter (MF) receiver or a minimum mean-square error (MMSE) receiver is employed for users' data detection. The total squared correlation (TSC) and the total mean-square error (TMSE) are proposed as the performance parameters for the MF and MMSE receivers respectively. These parameters need to be minimized in order to maximize the signal-to-interference ratios (SIRs) at the receivers' outputs. For a given FOBE bandwidth constraint, the sets of signature waveforms that minimize either TSC or TMSE are obtained from the prolate spheroidal wave functions (PSWFs). Furthermore, if the number of users is the size of a Hadamard matrix, then optimal signature waveforms can be obtained to maximize the individual SIR for every user. Due to the complicated nature of the PSWFs, simplified MF and MMSE receivers based on the Walsh signal space are developed.
Từ khóa
#Code division multiplexing #Bandwidth #Multiaccess communication #Multiple access interference #Matched filters #Mean square error methods #Wave functions #Signal design #Communication systems #Quality of serviceTài liệu tham khảo
varanasi, 1998, (1998, sept.) optimum signal design and power control for multiuser wireless communications under location-invariant bandwidth constraints, Proc Thirty-Sixth Allerton Conf Commun Contr and Comp
10.1109/ISIT.2000.866676
10.1109/35.714623
10.1002/j.1538-7305.1961.tb03976.x
10.1002/j.1538-7305.1961.tb03977.x
10.1109/TIT.1965.1053803
10.1109/18.782121
10.1007/978-1-4613-9323-8_7
10.1109/26.930624
10.1109/18.568697
10.1109/TIT.1974.1055219
10.1109/18.782119
sklar, 2001, Digital Communications Fundamentals and Applications
10.1109/MCOM.1980.1090291
10.1109/18.79901
cheng, 1989, optimal signal design for band-limited pam synchronous multiple-access channels, Proc 23rd Conf Information Sciences and Systems, 321
10.1109/18.335940
verdúverdu, 1998, Multiuser Detection
10.1109/26.476098
10.1109/26.855514