Large Set of CI Spreading Codes for High-Capacity MC-CDMA
Balasubramaniam Natarajan, Zhiqiang Wu, C.R. Nassar, Steve J. Shattil · IEEE Transactions on Communications · 2004
In this letter, a large set of spreading codes that doubles capacity in multicarrier code-division multiple-access (MC-CDMA) systems without any cost in bandwidth and with negligible cost in performance is introduced. This large set is comprised of: 1) complex spreading codes instead of conventional real-valued spreading codes and 2) two sets, each made up of orthogonal complex spreading codes, with minimum cross correlation between sets. Simulations performed over Rayleigh fading channels demonstrate 100% gains in terms of MC-CDMA capacity with negligible loss in performance.