Performance of quasisynchronous scale time code division multiple access for AWGN channel
Computers and Electrical Engineering
Computers and Electrical Engineering
IEEE Transactions on Wireless Communications
A hybrid MC-CDMA precoding scheme employing code hopping and partial beamforming
ICC'09 Proceedings of the 2009 IEEE international conference on Communications
Hi-index | 754.84 |
A new class of orthogonal code-division multiple-access (CDMA) systems is developed for efficient multiuser communication in environments subject to multipath fading phenomena. The key characteristic of these new systems, which we refer to as “spread-signature CDMA” systems, is that the associated signature sequences are significantly longer than the interval between symbols. Using this approach, the transmission of each symbol of each user is, in effect, spread over a wide temporal and spectral extent, which is efficiently exploited to combat the effects of fading. These systems generalize and improve on the spread-response precoding systems. Both efficient signature sets and efficient receiver structures for such systems are developed. Several aspects of the performance of the resulting spread-signature CDMA systems are presented, including both the achievable bit-error rate characteristics and the effective capacity of such systems. The results suggest that spread-signature CDMA may be an attractive alternative to conventional CDMA in a variety of application scenarios