Phase‐noise reduction by self‐injection locking in spatially extended tunnel‐diode oscillator

Abstract

A scheme is proposed for reducing phase noise in a spatially extended oscillator using tunnel-diode (TD) transmission line. It is observed that a voltage edge oscillates on a TD line when supplied by an appropriate DC voltage at the end. When the TD line is bypassed by a linear transmission line, part of the oscillating edge is inputted to and moves on the linear line to interact with the oscillating edge at the another crosspoint. The proper length of the linear line makes the bypassed voltage arrive at the crosspoint at the same time as the oscillating edge. It results in significant phase-noise reduction of the oscillating edge through self-injection locking. Herein, the principle of operation is described with its experimental validation.

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

“…Finally, we measured the properties of the TD line connected to 18 linear lines. The linear line dimensions were set at (M, K)=(2, 3), (3, 4), (4, 5), (5,6), (6, 7), (7,8), (8,9), (9, 10), (10,9), (11,10), (12,11), (13,12), (14,15), (15,16), (16,17), (17,18), (18,19), and (19,20). When trial and error optimization was applied, a mismatch occurred between M i and K i .…”

“…Recently, we investigated two different cells of a TD line bypassed by a linear line. 15 The terminal cells of the linear line detected the arrival of the forward-and backward-moving voltage edges on the TD line. The signal generated by the backward-moving edge can be made to travel along the linear line and interact with the forward-moving edge at the other end of the linear line by appropriately setting the delay caused by linear line transmission.…”

“…Recently, we investigated two different cells of a TD line bypassed by a linear line 15 . The terminal cells of the linear line detected the arrival of the forward‐ and backward‐moving voltage edges on the TD line.…”