基于差分酉空频调制的多天线DAB系统

MIMO-DAB Based on Differential Unitary Space-Frequency Modulation

在数字音频广播(DAB)系统基础上,引入酉空时码,提出了基于差分酉空频调制(DUSFM)的多天线DAB系统.该系统采用卷积码、时频交织和差分酉空频调制级联的编码调制形式,对无信道状态信息也可实现解调.理论推导证明所提系统可同时获得空、时、频三种分集.通过蒙特卡洛仿真,证实在时频双选信道、4发1收的条件下,为达到0.001的误码率,所提系统比原DAB系统有6.5 dB的信噪比增益,而同条件下CDD-DAB方案的信噪比增益仅为1.0 dB.从而验证了所提系统具有较高的分集增益.

Unitary space-time codes were introduced to the digital audio broadcasting （DAUB） system, and a multiple-antenna DAB system based on differential unitary space-frequency modulation （DUSFM） was proposed, which adopts a concatenation of convolutional encoder, time interleaver, frequency interleaver and DUSFM. In DUSFM-DAB, the receiver can perform demodulation without channel status information. Theoretical deduction proved that the DUSFM-DAB can obtain full spatial, temporal, and frequency diversities. By Monte Carlo simulation, with time-frequency selective fading 4 ×1 MIMO channel, to achieve a 0.001 bit-error-rate, the performance of the proposal scheme has a 6.5 dB SNR benefit compared with that of the original DAB, while the SNR benefit of CDD- DAB is 1.0 dB in the same condition, which verifies that the DUSFM-DAB has a higher diversity gain.