A Microstrip Array Antenna with Low Cross-Polarization and Sidelobe Level Simultaneously

In this paper, an x-band multi-layer microstrip array antenna with high gain and low sidelobe is designed by using microstrip patch unit and series-parallel mixed feeding network. The radiating layer of the antenna is composed of 8*16 microstrip patch elements. The phase between each elements is kept of the same, and the amplitude is approximately Taylor distribution. The feeding network and the radiating patches are located on both sides of the ground respectively in order to avoid the coupling between the network and the radiation patch. The simulation results show that the gain of the microstrip array antenna reaches to 23.6dB in the range of 8.9-9.1GHz, the sidelobe is lower than -27dB, the cross polarization isolation reaches to 80 dB, and the 3 dB beam scanning angle is about ±50°.