Broadband reduction of phase noise in a spatially extended tunnel‐diode oscillator through multiple self‐injection locking

Abstract

A self-injection locking scheme is proposed to reduce phase noise in a spatially extended oscillator that uses a tunnel-diode (TD) transmission line. When a linear transmission line is connected to each cell of the TD line, a part of the oscillating edge flows through the linear line. This wave on the linear line is reflected at its far end and flows back to the point of connection of the TD and linear transmission lines. By matching the time taken by the reflected wave on the linear transmission line to reach the point of connection with the time taken by the forward-moving oscillating edge to return to the point, the edge can be synchronized with the wave that flows back through each linear line. This multiple self-injection locking significantly reduces the phase noise of the oscillating edge. In this work, the technique of phase noise reduction is explained through numerical phase noise analysis using the perturbation projection vector of the system. Several experimental observations were made to validate the reduction of the phase noise in the oscillating edge traveling on the TD line.

General analysis of LC oscillator with active and passive transconductance amplification

“…Interference noise is caused by the unwanted interaction between the oscillator circuit and the outside world or between different parts of the circuit. Inherent noise comes from the basic properties of the circuit and can be reduced via noise reduction techniques [8][9][10][11][12][13][14] but cannot be eliminated.…”