Accession Number : ADP002457

Title :   Superconductive Tapped Delay Lines for Low-Insertion-Loss Wideband Analog Signal-Processing Filters,

Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s) : Withers,R. S. ; Wright,P. V.

Report Date : 1983

Pagination or Media Count : 6

Abstract : Transversal filters have been realized as miniature superconductive tapped electromagnetic delay lines. The low loss of superconductors permits the use of a compact stripline structure which offers useful delay at microwave frequencies. Taps are realized as backward-wave couplers or a impedance discontinuities. Chirp filters are formed by cascading such couplers of increasing length. Pulse expansion and compression have been demonstrated over a 2.6-GHz bandwidth. By weighting the taps, side-lobe levels have been reduced to 25 dB below the peak output. A coupled-mode analysis has been employed for predicting the response of this class of filters and has achieved very good agreement with experiment. The analysis also predicts that, if coupling were increased to reduce insertion loss below about 10 dB, significant phase distortion results with a commensurate degradation of side-lobe levels.

Descriptors :   *Filters, *Signal processing, Superconductors, Analog signals, Delay lines, Bandwidth, Insertion loss, Frequency

Distribution Statement : APPROVED FOR PUBLIC RELEASE