Dual-chip GaAs monolithic integration Ku-band phase-locked-loop microwave synthesizer

Two novel multifunction monolithic chips, GaAs microwave monolithic integrated circuit (MMIC) and large-scale integration (LSI) chips, have been developed to realize an extremely small and lightweight microwave synthesizer. The MMIC includes a voltage-controlled oscillator, a dual-output buffer amplifier, a balun, and dynamic/static prescalers. To integrate these functions on a single chip, each circuit has been drastically reduced in size by utilizing a uniplanar MMIC configuration. The LSI includes a dual-modulus prescalar, programmable counters, and a phase/frequency comparator. By incorporating these two monolithic chips in the structure, a Ku-band microwave synthesizer has been fabricated in an 11-mm×23-mm flat package. The synthesizer to which these multifunction chips were applied had a tuning range broader than 1 GHz in the Ku-band with a flatness within 2 dB_pp. In spite of low-Q monolithic circuitry, single-sideband (SSB) phase noise was as low as -70 dBc/Hz