DRM系统中OFDM解调的高效实现

High-Efficient Implementation of OFDM Demodulation for DRM

针对全模式DRM接收机,设计了一种混合结构的非2幂次FFT,以解调其OFDM信号。提出的方案综合运用了WFTA算法、同址乱序PFA算法和可变流模式基2点FFT算法。48kHz过采样策略简化了FFT结构。试验结果表明,存储器和基2点FFT的复用极大地减少了FPGA的硬件资源消耗,降低了便携式接收机的成本和功耗。

To demodulate OFDM signals of all-mode DRM receivers, a non-power-of-2 FFT mixture of nested WFTA, in-place out-of-order PFA, and radix-2 FFT of variable stream, is proposed. The FFT architecture is simplified by oversampling of 48 kHz. Experimental results show that, multiplexing of memory and radix-2 FFT decreases dramatically the requirement of FPGA hardware resource, and reduces effectively the cost and power consumption of portable DRM receivers.