High performance millimeter-wave front-end and antenna feed system based on IF beam forming networks

In order to obtain better angle estimation performance, the authors designed and realized a millimeter wave transceiver integrated with microstrip antenna array based on IF beam forming networks. The frontend included four hybrid millimeter wave T/R modules and four microstrip antenna subarrays. The high gain transmitting beam is obtained by spatial power combination, and the sum and difference receiving beam formed in the IF sum and difference network. Phase balance of the four transmitting channels and four receiving channels is adjusted by dielectric loaded microstrip transmission line. The radiation gain of antenna is 29.5 dB. Null depth of difference beam is -25.0 dB.