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Showing papers by "Jeffrey H. Shapiro published in 1983"


Proceedings ArticleDOI
13 Dec 1983
TL;DR: In this paper, the results from a measurement program at the MIT Lincoln Laboratory aimed at verifying a mathematical system model for a compact coherent laser radar which incorporates the statistical effects of target speckle and glint, local oscillator shot noise, and propagation through atmospheric turbulence are reported.
Abstract: Previous studies have established a mathematical system model for a compact coherent laser radar which incorporates the statistical effects of target speckle and glint, local oscillator shot noise, and propagation through atmospheric turbulence. This paper reports results from a measurement program at the MIT Lincoln Laboratory aimed at verifying the foregoing model. Simultaneous laser radar returns and scintillation sensor measurements were collected over a one kilometer path in various turbulence conditions, with the radar observing either a glint object (retro-reflector) or a speckle object (flame-sprayed aluminum calibration plate). Three modes of laser radar operation were employed: full field-of-view scanning, reduced field-of-view scanning, and staring. The principal conclusions drawn from analyzing these data are as follows. First, beam jitter must be included in the system model. Second, the jitter-corrected retro-reflector returns do show turbulence induced lognormal scintillation. Third, turbulence-induced beam jitter is the cause for staring-mode speckle target decorrelation.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

7 citations


Proceedings ArticleDOI
13 Dec 1983
TL;DR: In this paper, the maximum likelihood (ML) processors and Cramer-Rao (CR) performance bounds are developed for short pulse, chirped pulse, sinusoidal amplitude-modulated pulse, and sinusoid frequency modulated pulse wave-forms.
Abstract: Coherent laser radars used for 3-D imaging and aerosol/pollutant sensing collect target returns which comprise a range-spread speckle process. This paper addresses a class of waveform design/waveform evaluation problems for such radars. The maximum-likelihood (ML) processors and Cramer-Rao (CR) performance bounds are developed for short pulse, chirped pulse, sinusoidal amplitude-modulated pulse, and sinusoidal frequency-modulated pulse wave-forms. All four of these waveforms are shown to have nearly identical ultimate range accuracies. However, range accuracy is not the only performance criterion of interest; range resolution, ambiguity, and anomaly must also be considered. Analysis and discussion of some of these aspects of waveform selection are included in the paper.

3 citations


Proceedings ArticleDOI
12 Jul 1983
TL;DR: Theoretical treatments of atmospheric wave propagation draw upon work on micrometeorology of the medium, and feed work on the design and performance analysis of communications and radar systems as discussed by the authors.
Abstract: Atmospheric electromagnetic wave propagation plays a crucial role in determining the performance of communication and radar systems that operate at millimeter through visible wave-lengths. Theoretical treatments of atmospheric wave propagation draw upon work on the micrometeorology of the medium, and feed work on the design and performance analysis of communications and radar systems. This paper will illustrate some of the features of the foregoing hierarchy, focusing on the interaction between the propagation and system analyses. Specific examples include: optical communication through atmospheric turbulence, coherent laser radar operation in atmospheric turbulence, and millimeter-wave communication through rain.

1 citations