Exact field expressions for a concentric circular-loops antenna above a PEC ground plane

Exact magnetic field expressions are derived for a system of concentric circular-loops antenna above a perfectly electric conducting (PEC) ground plane in this paper. The current distributions and dimensions of the loops are arbitrary. Simplified expressions for the antenna with uniform current loops and the fields on the axis of the antenna are obtained as special cases from the general expressions. Moreover, the static magnetic fields for concentric current loops are obtained from the general expressions by letting the propagation constant approaching zero. The numerical results from the field expressions presented in this paper are in excellent agreement to those from AN-SOF simulation software, which check the correctness of these expressions.