摘要 |
Co-channel interference of a frequency modulated signal represented by complex signal samples is reduced by amplitude limiting each sample and non-linearly filtering the limited samples. The non-linear filter low pass filters the limited samples, multiplies the filtered samples by their complex conjugates, and high pass filters the products to produce resultant signal samples. It also squares the filtered samples, low pass filters the squared samples, multiplies the filtered squared signals by the complex conjugates of the filtered samples, combines the result with said resultant signal samples and the filtered samples, and low pass filters the combined signal to produce samples having reduced co-channel interference. The limiter and non-linear filter can be constituted by a digital signal processor.
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