Design and Performance of a Multiple-Loop Frequency Synthesizer.

摘要

The report presents the results of the design and fabrication of a Multiple-Loop Frequency Synthesizer. The design utilizes frequency control loops to extend the capture range of a phase-locked loop used to provide frequency stability. No harmonic generators,mixers,or filters are used,in the usual sense; a single crystal oscillator is required. The synthesizer is small,light weight,accurate to within plus or minus 0.0025% of the programmed frequency,covers the AM broadcast band (500kHz to 1600kHz),and is electronically tunable in 10kHz steps. Unwanted sidebands 5kHz and 10kHz away from the programmed frequency have relative magnitudes of -28db and -40db,respectively. (Author)