Entire-domain versus subdomain attachment modes for the spectral-domain method of moments analysis of probe-fed microstrip patch antennas

Two different attachment modes that are widely used within the spectral-domain method of moments (MoM) analysis of probe-fed microstrip patch antennas are investigated and compared. Either of these attachment modes, the one being an entire-domain mode and the other a subdomain mode, is required for the accurate analysis of probe-to-patch junctions when used together with the MoM. In this paper, more light is shed on the ability of either approach in modeling microstrip patches of various sizes, residing on planar multilayered substrates, ranging from quite thin to relatively thick. Through a comprehensive comparison between numerical and experimental results, it turns out that the subdomain approach is somewhat more versatile than the entire-domain approach.