TDS-OFDMA: a novel multiple access system based on TDS-OFDM

As the key technology of Chinese national digital television terrestrial broadcasting (DTTB) standard, time domain synchronous OFDM (TDS-OFDM) utilizes known training sequence instead of cyclic prefix (CP) as the guard interval between adjacent inverse discrete Fourier transform (IDFT) blocks to achieve better system performance. Until now, TDS-OFDM was primarily used in downlink broadcasting. When TDS-OFDM is directly used in the uplink, it is difficult to eliminate the superposed interferences caused by different training sequences and IDFT blocks from multiple users. To solve this problem, a novel scheme called time domain synchronous orthogonal frequency division multiple access (TDS-OFDMA) is proposed in this paper. The novel space-time frame structure of the TDS-OFDMA scheme is proposed to achieve joint cyclicity reconstruction as well as joint channel estimation at the receiver. Simulation results show that the proposed scheme can achieve better bit error rate (BER) performance than conventional OFDMA system under highspeed mobile environments.