Analysis and design of a strain sensor based on a microstrip patch antenna

A microstrip patch antenna strain sensor operating at 5 GHz has been designed based on the relation between the resonant frequency and the length of the microstrip patch antenna. Testing results show that the resonant frequency of the microstrip patch antenna is 4.924 GHz, which agrees with the simulation. The resonant frequency of the microstrip patch antenna decreases linearly with the increase of the applied strain. The shift of the resonant frequency is 3.6 MHz when strain is 0.1%. This microstrip patch antenna strain sensor can be integrated with other components easily and have a great potential applications in structural health monitoring systems.