利用离散信号空间上的最小能量(小波)框架对升余弦脉冲信号展开去噪算法的研究。对于所给的2组不同最小能量框架,升余弦脉冲信号和加性高斯白噪声的抽样离散信号在这2组框架的各个子数列下的分解系数将出现明显不同的统计特征。据此给出了2个具体的阈值去噪算法,两者都充分利用了最小能量框架在信号去噪应用上的优点,在保持发送原始信号成分的同时去除了部分噪声成分,获得了较好的处理效果。仿真结果表明,当调制方式为BPSK且升余弦脉冲信号受加性高斯白噪声影响时,如果利用2个算法对接收波形进行去噪预处理,则接收信号的信噪比大幅度提升,在误码率上可以分别获得3.1dB和2.7dB左右的性能增益。
The de-noising algorithms were proposed for the raised cosine pulse signal using minimum-energy(wavelet) frame in the discrete signal space.For the given two minimum-energy frames,the decomposition coefficients of sampled sequence appeared significant statistical characteristics difference between the raised cosine pulse signal and additive Gaussian noise under the frames' sub-sequences.Based on this,two threshold de-noising algorithms were provided to makes full use of the merit that the frame was fit for the de-noising work,they removed partial noise component while keeping the component of original signal and got efficient de-noising result.The simulation results show that,when the modulating method is BPSK and its raised cosine pulse signal is polluted by the additive Gaussian noise,then if add a pre-processing link to denoise the receiving waveform using the algorithms,the receiver can greatly increase the sig-nal-to-noise ratio of receiving signal and have about 3.1dB and 2.7dB performance gain of bit error ratio,respectively.