Design of controlling circuit for varactor diodes based on K-band pattern reconfigurable antenna

A controlling circuit for varactor diodes based on K-band substrate integrated waveguide (SIW) leaky-wave antenna is presented in this paper to accomplish pattern reconfiguration. The varactors' DC bias is supplied by a sawtooth wave generated from the FPGA which allows automatic and continuous variation of the capacitance of the varactors. An isolating circuit between DC voltage and RF is applied to the antenna to make it work properly. Consequently, a design of pattern reconfigurable antenna is accomplished and beam scanning is detected from 21GHz to 23GHz.