Finite element simulation design of saw micro pressure sensor is carried out by COMSOL software.In order to adapt to the characteristics of surface acoustic wave（SAW） micro-pressure sensor with low resonant frequency and small size

a dual-frequency microstrip antenna is designed by using capacitive load and short-circuit probe.The design has two passbands

one of which is guaranteed to be in low frequency of 810 MHz and the other pass band at 2.16 GHz.The simulation results of HFSS software show that the design has good gain and directivity on the premise of ensuring the small size and low frequency of the antenna.