Circular polarization microstrip antenna at W band

A circular polarization array antenna at W band is designed by analyzing and comparing different feeding forms，using constant amplitude and inphase feeding and waveguidemicrostrip transition.According to the theoretical analysis and simulation results，the loss of W band antenna can be reduced，good axial ratio and suitable arrangement of feeding network can be realized by choosing proper dielectric，using waveguidemicrostrip transition and constant amplitude and inphase feeding of each unit radiation patch，which is ideal for the realization of circular polarization array antenna at W band.The bandwidth of the 8×8 array antenna are 43% when S(1，1)<〖KG-*4〗-15 dB.The beamwidth of the antenna is 11° when axial ratio is below 3 dB.And the maximum achievable gain of this antenna is 206 dB.Test and simulation results are in good agreement.