INVESTIGATIONS OF TRANSPOSED GAIN OSCILLATORS USING LOW FREQUENCY LIMITERS AND AJC JITTER SUPPRESSION TECHNOLOGY

摘要

The Transposed Gain Oscillator was described by Page-Jones and Everard in the 10th EFTF [1]. The oscillator achieves low flicker phase noise at high frequency by breaking the oscillator feedback loop, mixing down to a low IF, at which a good noise figure and high gain can be achieved, and then mixing back up to final frequency. One purpose of this paper is to demonstrate the effect that an AM limiter can have on the final oscillator spectrum. The Anti-Jitter Circuit (AJC) Jitter Suppression Technology for the reduction of phase noise and time jitter has been described in various EFTF papers [2-6]. A second purpose of this paper is to describe and characterise a proposed double transposed gain oscillator where an AJC jitter suppression circuit is used at 10 MHz to improve the phase noise of both the main oscillator and the secondary mixing down-and-up oscillator.