Wide-Band Superconductive Chirp Filters

摘要

Chirp filters are described that consist of miniature tapped superconductive stripline. The stripline consists of 40-micron-wide niobium thin films in a spiral pattern on 125-micron-thick silicon wafers, and tapping is effected by backward-wave couplers between neighboring lines. Sophisticated fabrication and packaging techniques have led to a now mature technology. Devices with 2.6 GHz bandwidth and time-bandwidth products of 98 are routinely fabricated that exhibit amplitude errors within a few tenths of a decibel and phase errors within a fractions of a degree of theoretical. In pulse-compression tests, matched amplitude-weighted devices yield peak relative side-lobe levels of -32 dB. Reprints. (RH)