2by2 rectangular microstrip patch array

Single elements of the microstrip patch array are fed by a microstrip feed line connected to the edge of the patch. The 2 by 2 microstrip array may be fed using a number of techniques. The single-layer microstrip array, as used here, is fed by a corporate network with the feed lines printed on the same side of the substrate as the patch elements. The four co-polarized patches of this antenna are fed from a single feed point. Mitered sections are used on 90 degree corners as well as on T-junctions to reduce mismatch due to reflections from discontinuities. Quarter wave transformers have been added to allow some degree of impedance matching. Ohmic and dielectric losses in the feed network, as well as parasitic radiation from the feed network, result in limitations on the efficiency of the antenna. The use of low loss tangent dielectrics counteracts some of these loss mechanisms.