Research on Pretreatment Method of eLORAN Received Signal Based on Spectral Subtraction

To eliminate or reduce the noise and interference and improve the signal quality, a pretreatment method of eLORAN received signal based on spectral subtraction is proposed, aiming at eliminating or reducing the noise and interference in the received signal. This method is a spectrum estimation method. Firstly estimate noise and interference power spectrum, then acquire the useful signal power spectrum by subtract the noise and interference power spectrum from received signal power spectrum, the useful signal can be reconstructed in combination with the received signal phase recovery. The theoretical analysis and experimental results show that the proposed method can effectively eliminate noise include in-band high frequency noise and carrier interference. At the same time, it can accurately recover the useful signals and the algorithm is simple and easy to implement. This method realizes application innovation and has important reference value for the design of various types of eLORAN navigation and timing receivers.