Surface Acoustic Wave Fourier Transform Module.
Abstract
The application of high speed surface acoustic wave, nonlinear delay line devices to real time computation of parallel input-serial output Discrete Fourier Transforms was studied. A laboratory model DFT module using a 32 input Two-Dimensional Diode-Convolver was designed, fabricated, evaluated, and delivered. Transforms of arbitrary 32 point signals were simulated with this module with transform readout times variable from semi-infinite to as short as 1.16 microseconds Error signals in the DFT output were shown to be no worse than -20 dB and can be significantly reduced by further development. An initial study was also carried out on a linearized product mixer using a log amplifier - dual gate FET configuration. It was shown that mixers of this type would be used to build a linear DFT module with the same high speed demonstrated in the delivered module but with input-output transfer function linear to + or - 2 dB over a 40 dB dynamic range. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1976
- Accession Number
- ADA030374
Entities
People
- T. M. Reeder
- T. W. Grudkowski
Organizations
- United Technologies Corporation