Transmission and reception of TDD multicarrier CDMA signals in mobile communications system

Abstract

Multicarrier CDMA (MC-CDMA) signal coming from each user suffers from the Multiaccess interference (MAI) caused by the loss of orthogonality among different user's spreading codes. In order to restore the orthogonality, this paper presents a precoding (pre-equalization) technique to equalize each subchannel. Through the precoding transmission, the receiver can achieve multiaccess interference (MAI) free reception and will not amplify the power of the noise.