Title :
New approximations to J0 and J1 Bessel functions
Author_Institution :
Dept. of Electr. Eng., Florida State Univ., Tallahassee, FL, USA
fDate :
8/1/1995 12:00:00 AM
Abstract :
New approximate solutions to the 0th- and 1st order Bessel functions of the first kind are derived. The formulations are based upon using a new integral with no previously known solution. The new integral in the limiting case is identical to the 0th-order Bessel function integral. It is solved in closed form, and the solution is expressed as a simple even order polynomial with integer coefficients. The polynomial coefficients are all of integer value. The 1st-order Bessel function approximation can then be found through a simple derivative. Comparisons are made between the exact solution, classic solutions, and the new approximation. The new approximation proves to be much more accurate than the classic small argument approximation. It is also sufficiently accurate to bridge the gap between the classic large and small argument approximations and has potential applications in allowing one to analytically evaluate integrals containing Bessel functions
Keywords :
Bessel functions; electromagnetic wave scattering; function approximation; integral equations; polynomials; 0th-order Bessel function; 1st order Bessel function; J0 Bessel function; J1 Bessel function; approximate solutions; closed form; derivative; even order polynomial; function approximation; integer coefficients; integral; polynomial coefficients; small argument approximation; Antenna measurements; Antennas and propagation; Data mining; Dielectrics; Electromagnetic propagation; Frequency measurement; Polynomials; Radar antennas; Radar scattering; Resonance;
Journal_Title :
Antennas and Propagation, IEEE Transactions on