A NEW ORTHOGONAL MULTICARRIER CDMA SYSTEM

In this paper, a new multicarrier MC-CDMA system is proposed. Comparing with the conventional MC-CDMA system, the difference is that transmitted data bits are serial to parallel converted to a number of parallel branches first, then each branch is modulated using a group of orthogonal subcarriers. Noted that on each orthogonal subcarrier branch, transmitted data bit after serial to parallel converted is modulated with a chip of a PN(Pseudorandom Number) sequence, not a whole PN sequence. This system can utilize the transmission bandwidth more efficiently and achive frequency diversity. Furthermore, this system lowers the data rate of each carrier branch, so it is easier to make PN sequence synchronized. The performance of the system is analysed in a Rayleigh fading channel.