Input impedance, bandwidth and efficiency of an edge modulated microstrip antenna

A sinusoidally edge-modulated microstrip patch antenna has been analysed using the modal expansion cavity model. The investigations have been carried out to explore the input impedance, bandwidth and radiation efficiency of the modulated structure against its physical parameters like the modulation depth and periodicity. The simulated results clearly show that the bandwidth increases with modulation depth under certain conditions of excitation. The analysis further shows that the modulated structure provides a lot of flexibility in matching the antenna to the standard feeder lines. Experimental results tally satisfactorily with the theoretical data.