A 15 GHz single stage GaAs dual-gate FET monolithic analog frequency divider with reduced input threshold power

摘要

An analog frequency divider is considered that operates on the basis of induced subharmonic oscillation and is composed of a mixer, a bandpass filter, amplifiers, and a feedback circuit. Although this frequency divider is inherently suitable for high-frequency operation, it possesses two substantial drawbacks: a complex circuit configuration is needed because of poor separation of the signals, and the input threshold power is undesirably high. The authors intend to mitigate these drawbacks by using a dual-gate FET mixer to improve the isolation of the signals, and by introducing a rejection filter at the output port to increase the conversion gain. The dual-gate FET contributes to simplifying the circuit configuration and the rejection filter results in reducing the input threshold power. The design, fabrication, and testing of the resulting 15-GHz single-stage monolithic GaAs FET analog frequency divider are described. Measured input/output characteristics at 14.8 GHz are given, and a high conversion gain of 0.0-2.5 dB is obtained for an input power of 2.0-9.5 dBm.