Abstract:

A single carrier two dimensional code and frequency division multiple access (SC-2DCFDMA) system is proposed. The contradiction between spreading factor and subband width in common single carrier code and frequency division multiple access (SC-CFDMA) system is resolved by the use of time frequency two dimensional spreading matrix. The mathematical models of SC-2DCFDMA transmitter and receiver are constructed. The analytical bit error rate (BER) under additive white Gaussian noise channel and frequency selective channel are analyzed. Simulation results show that the analytical and simulated BER curves coincide with each other. With equal spreading factor, SC-2DCFDMA system has narrower user subband and superior BER performance. In a multi user scenario, although channel frequency selectivity induces the orthogonality loss of the frequency domain spreading code, this kind of loss could be compensated by the orthogonality of time domain spreading code. Thus multi user performance of SC-2DCFDMA system is better than SCCFDMA system.