Acousto-Optic Fourier Transform Devices for Surveillance Signal Processing

摘要

Acousto-optic techniques have been investigated for application to the Fourier-transform requirements of the Gemini surveillance concept. Acousto-optical computation of continuous and discrete Fourier transforms have been performed using a time-integrating architecture. Time-integration in conjunction with diode lasers and bulk optics can be used to produce inherently compact optical systems, and several compact processor concepts have been demonstrated. Performance parameters and tradeoffs have been analyzed for these processors, and present device limitations identified. 30 dB dynamic range has been demonstrated. Additional concepts for miniaturization, including application of integrated optics, are discussed. Multichannel operation will be required in Gemini, and the Fourier-transform devices developed here have been shown to be easily adaptable to multichannel operation. Two-channel operation has been demonstrated; several multichannel concepts have been evaluated, and one design is being implemented. (Author)