Design of Electronically Controlled Filter Power Divider Based on Liquid Crystal

Abstract

The wireless communication system is one of the most important facilities of fuel cell hybrid power tram (FCHPT), which provides a strong guarantee for efficient and safe operation. As an indispensable part of the RF front-end of the transmitter and receiver, the miniaturization and high-performance trends of filtering power dividers are becoming evident. Based on the principle of filter power divider, a capacitor loaded power divider filter is designed and fabricated in this paper. The center frequency of the designed power divider filter is 30 GHz, the return loss S11 is less than −10 dB in the range from 29.2 to 31.6 GHz, and the insertion losses S21 and S31 are less than 5.3 dB. The frequency shift of 1.8 GHz can be achieved by changing the dielectric constant of the liquid crystal with an applied bias voltage, which can be used in millimeter wave communication system.