This invention addresses the scenario in which a weak desired signal reaches a poorly-selective receiver along with a strong radar signal. Traditionally, this scenario is addressed using an Automatic-Gain-Control (AGC) to fit the strong signal into the dynamic range of the receiver. However, AGC based method is not optimal because it desensitizes the receiver, sacrificing the signal-to-noise-ratio of the desired signal.
We propose the use of an auxiliary receive path to address this problem of strong neighboring-channel signals. In this new method, receiver gain is not lowered to avoid clipping. Instead, the strong signal is allowed to clip and distort the desired signal. It is shown in this paper that only a sub-set of the symbols contained in the desired signal will be distorted. Hence, by leveraging the redundancy of the desired signal (due to forward error correction), undistorted symbols can be used to estimate the information content of the desired signal. The auxiliary path samples the envelope of the strong neighboring-channel signal and informs the decoder which symbols are clipped (or "bad"), and which symbols are not clipped (or "good"). This additional information is shown to improve the estimation performance of the decoder. Using simulation and hardware-based experiments, it is shown that auxiliary-path-based receivers can obtain a significantly better throughput performance than AGC-based receivers.