IF frequency tunable self oscillating mixer using cylindrical dielectric resonator VCO

In this paper a novel Self Oscillating Mixer (SOM) design is demonstrated which has the capability of tuning the IF frequency. A voltage controlled cylindrical dielectric resonator oscillator acts as both the local oscillator and the mixer for RF frequency. The voltage controlled oscillator (VCO) frequency is controlled by a reverse biased varactor and it simultaneously tunes the IF frequency after mixing. The VCO works in X band. A 40 MHz change in IF frequency can be observed with varactor reverse bias voltage ranging from 0–18 V. The conversion loss of the mixer is 19 dB. The proposed self-oscillating mixer is compact and is suitable for low profile transceiver applications.