Poly-line approximation algorithm research of induced voltage from rectangular loop over layered earths

This paper discusses the poly-line approximation method for solving TEM response and the induced voltage of the rectangular loop over uniform layered earths. Because the non-zero offset expression of TEM response of rectangular loop contains a double Bessel function, according to asymptotic characteristic of the staple volume, the integration interval can be divided into [0,λ₀] and [λ₀,∞], and different calculating methods are adopted in two integration intervals. The results of the solution and the whole solving course are given in the paper. The results demonstrate that the methods are efficient and valid, and the results are accurate and scientific.