A hybrid MoM-asymptotic and circuit based analysis of the radiation/receiving by large finite patch antenna arrays with a printed feed network

The problem of electromagnetic radiation and receiving by large finite periodic microstrip patch antenna arrays on a grounded slab together with a feed network is analyzed. In general, the more the number of elements in an antenna array, the larger the size of the corresponding feed network and the more computational resources required to solve this problem using full-wave or MoM analysis. Furthermore, since feed networks have to be designed such that they can operate well with corresponding antenna arrays in order to achieve desirable performance, in most cases their design process may require many iterations, which can result in a highly inefficient and time-consuming process and can be intractable for large antenna arrays. To improve the efficiency of the analysis of such problems, an approximate hybrid method is developed; it decomposes the problem into two major parts, one dealing with antenna arrays alone and the other dealing with feed networks alone; then, a generalized Thevenin´s theorem is applied to combine the two parts systematically. The approximation in this hybrid approach results from the circuit solver that does not provide any contribution to the radiation by the feed lines. It is assumed that the feed lines are designed so that their radiation is negligible.