On integral computation of Bessel function for 3-D electromagnetic scattering computation in the earth half-space

Using the integral equation method, the integral computation of the primary field of the 3-D electromagnetic scattering problem in the earth half space is an integral of double Bessel functions. The dipole model is usually taken for its numerical computation. The integral with integrand of double Bessel function is simplified to the integral of single Bessel function and is computed with the Hankel transformation. In this paper. A method of finding the zero points and dividing the intervals is used to compute the integral of double Bessel function. Taking different integral parameters, the integral results of double Bessel function are compared with those of single Bessel function with Hankel transformation. The errors of these two algorithms are discussed.