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This paper describes the temporal response of an acoustooptic spectrum analyzer to pulse-modulated cw signals. The detected waveforms from a real-time photodetector array are analyzed as a function of pulse width, weighting function parameters, and relative photodetector to spectral centroid location. The input pulse envelope is modified in the forms of signal duration stretching, the appearance of a flattop, multiple humps, and longer rise and fall times. Various schemes are discussed on the determination of the pulse width from the detected waveform.

A general analysis is presented of an interferometric acoustooptic signal processor for simultaneous direction finding and spectrum analysis. Topics include amplitude window weighting function, scaling factor, error tolerance analysis, linear periodic vs aperiodic arrays, and comparison between microwave and optical antenna array far-field patterns. Finally a specific design example is given of synthesizing an optimum array.

This paper examines the instantaneous Fourier power spectrum for different types of radar signals such as cw, pulse-modulated cw, and linear FM signals using an acoustooptic spectrum analyzer. The effects on the time-integrated output intensity distribution, due to the truncation of the propagating acoustic signal by the finite aperture width of the Bragg cell and the amplitude weighting on the signal, are also analyzed. Some experimental results on pulse-modulated cw and linear FM signals are presented and then compared to theory.