Signal Flow Graph for a Probe-Fed Microstrip Patch Antenna

Complex coupling environments are difficult to represent analytically. Signal flow graphs offer an analysis method for such networks, allowing network elements to be treated individually. These elements can then be reintegrated and ultimately analyzed using Mason´s Gain Rule. This letter presents a signal flow graph of the microstrip patch antenna, a simple coupling network, that is often an element in large, more complex coupling networks. Comparisons between results from the signal flow graph and the traditional transmission line model are provided.