介绍了脉冲密度调制(PDM)信号的原理和特点,比较了基于梳状滤波和基于频域滤波的解码算法、性能和计算复杂度。仿真结果表明,梳状滤波解码算法复杂度低,解码后信噪比基本无损失,设计起来较为复杂;频域滤波解码算法复杂度高,解码后信噪比可做到基本无损失,设计使用较简便。
The principle and characteristics of PDM(Pnlse Density Modulation) signal are introduced. The complexities and performance of two decoding algorithms are compared and evaluated, which are based on the comb filtering and the frequency domain filtering. The simulations show that the demodulation based on the comb filtering has lower computation load and little SNR lost, but is quite complex and hard to be implemented. The demodulation based on the frequency domain filtering has higher computation load and smaller SNR lost, and is easy to be understood and implemented.