A millimeter wave variable polarization monopulse frontend based on microstrip array antenna

A millimeter-wave variable polarization monopulse frontend based on microstrip array antenna is presented in this paper. The front-end consists of four millimeter wave T/R modules and a microstrip antenna with four linear polarized subarrays. The polarization of far field electric field can be configured by amplitudes and phases of the feeds. Besides the angle error of monopulse angle estimation, the polarization information of the target can be also obtained simultaneously. Digital controlled phase shifters are used to configure the phases of feeds and to change the polarization of radiation pattern. Digital virtual polarization synthesis and digital monopulse sum-difference are realized in digital processing module.