Surface Wave Parametric Processors and Long Delay Lines.
Abstract
Design procedures for wrap-around, helical SAW delay lines of large time delay together with large bandwidth are developed. The frequency dependence of the various loss mechanisms, i.e., crystal loss, air loading loss, and diffraction loss, are studied. This includes an analytical treatment of diffraction loss in unguided SAW delay lines. Loss balancing procedures are developed, for designing interdigital transducers to equalize the frequency tilt due to frequency dependence of the loss factors and produce a level passband, and procedures for removing the residual passband curvature are developed. These are applied to graded, phase weighted interdigital transducers. Summaries are given of time delay and bandwidth values available in delay lines on BGO, for typical values of delay line parameters and dynamic range. Delay line designs are presented for time delays of 0.1, 0.5, and 1 millisecond time delay. Experimental delay lines for these time delay values are described, one having time delay of .91 milliseconds and bandwidth of 65 MHz, for a time bandwidth product of 60,000, with center frequency of 83 MHz. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 08, 1975
- Accession Number
- ADA020983
Entities
People
- C. M. Fortunko
- Herbert John Shaw
- S. L. Quilici
Organizations
- Stanford University