The technology of normalized digital orthogonal detection and its application

The method of normalized digital orthogonal detection is proposed according to the frequency of surface Magnetic Resonance Sounding (MRS) signal is much bigger than bandwidth and it has no influence on its key parameters. Constructing MRS signal with noise in accordance with its characteristics, then processing them using normalized digital orthogonal detection, the simulation results show that with the same SNR, the higher the sampling frequency, the bigger SNIR (signal noise improvement ratio). Embedding the normalized digital orthogonal detection unit in MRS instrument, and conducting laboratory test and field detection, the results show that this method is effective to extract the envelope of MRS signal, and SNR can be improved, too. At the same time, it simplifies hardware and improves the stability of orthogonal detection system.