The Design of a Ka-band Broadband Circularly Polarized Microstrip Antenna and Array

A novel Ka-band broadband circularly polarized microstrip patch antenna fed by rectangular aperture coupling was proposed Firstly,the effect of key parameters on axial ratio(AR) was analyzed.In order to improve AR bandwidth and impedance bandwidth,a 4×4 broadband circularly polarized microstrip antenna array using sequentially rotated technique was designed.The simulation result shows that the impedance bandwidth(S11-10dB) of the antenna array is 25%(31.4-40.2GHz),the AR bandwidth(AR3) is 17%(31.8-37.8GHz).