Detection of tropospheric scatter array signal based on the truncation of multipath fading time and frequency domain characteristics

摘要

Microwave scattered by the troposphere can propagate Over-The-Horizon(OTH), how to effectively detect the received signal using its signal characteristics is the most important issue in troposcatter target reconnaissance. The received signal behaves with low signal to noise ratio (SNR), multipath fading. In order to effectively detect, the SNR needs to be enhanced utilizing the signal characteristics. This paper analyzes the signal multipath fading and finds energy diffusion characteristics affected by multipath fading in the time and frequency domain. Based on this, an appropriate signal truncation strategy is designed respectively in time, frequency domain to obtain the energy-concentrated part to maximize truncation gain. Next, the signal detection is carried out after the paper accumulates signal energy of the truncated part. The algorithm does not need any prior information which is effective in the non-cooperative circumstance. Finally, the simulation results validate the detection performance of the proposed algorithm is better than the traditional energy detection. The proposed one can satisfy the detection need of the troposcatter signal.