Voltage controlleddielectric resonator oscillator usingthree-terminal MESFET varactor

The MESFET can be used as a three-terminal MESFET varactor by employing gate depletion capacitance Cg. Using this concept, a new VCDRO (voltage controlled dielectric resonator oscillator) has been designed. The VCDRO produced 10.17 dBm output power at a frequency of 11.00 GHz and tuning bandwidth of 70.2 MHz. The advantage of using the MESFET as a three-terminal varactor is to let the MESFET perform both roles at the same time, thus simplifying the circuit configuration and fabrication. This finding demonstrates the potential of using both real and imaginary parts of the equivalent impedance of the active device.