Pseudo-random electromagnetic exploration based on Invert-Repeated m-Sequence correlation identification
Tang Jing · Chinese Journal of Geophysics · 2008
By analyzing the source signal characteristics of electrical prospecting using frequency varying or 2~n series pseudorandom signal,a novel electromagnetic method based on system identification using Invert-Repeated m-pseudo-random binary Sequence(IRmPRBS)is introduced. The IRmPRBS signal has the similar auto-correlation with white noise and the spectrum distributed at same space within its wide bandwidth.Derived from Wiener-Hopf equation,the elements of the earth impulse response correlation identification using IRmPRBS signal is analyzed.It is proved that properly selecting the parameters including the length of sequence, clock frequency,and so on for IRmPRBS signal generation can result in a good interference suppressing and a higher resolution for earth electrical system identification.We also studied the signal parameters selection principle for good measuring precision and exploration resolution.In a word,this paper is the groundwork to develop the new method and instruments for electrical exploration with higher precision and resolution.