Radiation field computation of leaky coaxial cables by finite-difference time domain in cylindrical coordinates and equivalent source integration

A combined scheme involving a conventional perfectly matched layer and lossy material is proposed for absorbing both the radiating and evanescent waves of leaky coaxial cables (LCX) efficiently. After parameter optimisation and correctness verification, the combined absorbing boundary is used to calculate the near field of LCX with horizontal triangle slots. The radiation field is then obtained by integrating the near field on an equivalent surface surrounding the cable. The LCX with horizontal triangle slots is desired to have advantages in generating smoother field distribution around the cable, especially for the vertical component.