High-performance MC-CDMA via carrier interferometry codes

This paper introduces the principles of interferometry to multicarrier code division multiple access (MC-CDMA.). Specifically, we propose the use of M C-CDMA with novel carrier interferometry (CI) complex spreading codes. The CI/MC-CDMA method, applied to mobile wireless communication systems, offers enhanced performance and flexibility relative to MC-CDMA with conventional spreading codes. Specifically, assuming a frequency selective Rayleigh-fad ing channel, CI/MC-CDMAs performance matches that of orthogonal MC-CDMA usi ng Hadamard-Walsh codes up to the MC-CDMA N user limit; and, CI MLC-CDMA pr ovides the added flexibility of going beyond N users, adding up to N - 1 ad ditional users with pseudo orthogonal positioning. When compared to MC-CDMA schemes capable of supporting greater than N users, CI/MC-CDMAs performanc e exceeds that of MC-CDMA. Additionally, this new system is analyzed in the presence of phase jitters and frequency offsets and is shown to be robust to both cases.