A self-consistent, integral-equation technique for the analysis of ICRF antennas

A code has been developed for the self-consistent evaluation of the current distribution, and the input impedance of a strap antenna facing a plasma in a slab geometry, retaining the presence of a back-wail. The calculation is based on the solution of an Electric Field Integral Equation (EFIE) in the spectral domain, applying the Galerkin, weighted residual method. Adopting ''rooftop'' basis and test functions, no assumptions have been made on the current distribution. The Green's function is derived from the cold plasma impedance by means of an equivalent transmissions line model, retaining both the slow and the fast wave contributions. An efficient extraction of asymptotic Green's function behavior has taken to a significant reduction in the spectral integration support. A sample analysis has been made on an IGNITOR like antenna structure, demonstrating the agreement with previous results. The code is modular both in its theory background and implementation, and therefore open to significant improvements as the introduction of a three-dimensional current distribution, the presence of the antenna recess and of the Faraday shield, and the adoption of a more accurate plasma model.