Chirp Bandwidth Estimation of Pulsed IMPATT Oscillator at 94 GHz Window: A Simplified Approach

摘要

Chirp bandwidth viz. intra-pulse oscillation frequency variation is an inherent property of IMPATT devices operating in pulsed mode to obtain high peak-power. In this paper, a simplified approach to compute chirp bandwidth, without the detailed knowledge of the embedded W-band circuit, is presented. The analysis has been based on a small-signal simulation model and transient thermal model of a typical silicon double-drift region structure at 94 GHz frequency band. The diode has been optimized for an optimum punch-through factor. It is observed that the diodes have a specific optimum temperature range of operation, to achieve a stable and high-output operation. The computed chirp bandwidth of the order of 1.8 GHz agrees reasonably well with the values reported in the literature. Variation of chirp bandwidth with frequency is also reported in this paper.