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Hayden, W. L.

Publications and source records attributed to Hayden, W. L..

NASA's flight-technological development program - A 650 Mbps laser communications testbed

A 650 Mbps laser communications testbed under construction for the development of flight qualifiable hardware suitable for near-term operation on geosynchronous-to-geosynchronous crosslink missions is presented. The program's primary purpose is to develop and optimize laser communications unique subsystems. Requirements for the testbed experiments are to optimize the acquisition processes, to fully simulate the long range (up to 21,000 km) and the fine tracking characteristics of two narrow-beam laser communications terminals, and to fully test communications performance which will include average and burst bit error rates, effects of laser diode coalignment, degradation due to internal and external stray light, and the impact of drifts in the optical components.

Hayden, W. L.

Spectral Analysis Program (SAP)

Program eliminates or reduces time-consuming aspects of computation of power spectrum for high-frequency communication system. This program was written in FORTRAN IV for UNIVAC 1230 or 1108 computer.

Detchmendy, D. M.

Compression and R-wave detection of ECG/VCG data

Application of information theory to eliminate redundant part of electrocardiogram or vectorcardiogram is described. Operation of medical equipment to obtain three dimensional study of patient is discussed. Use of fast Fourier transform to accomplish data compression is explained.

Hayden, W. L.

Development of spectral analysis math models and software program and spectral analyzer, digital converter interface equipment design

Spectral analyses of angle-modulated communication systems is studied by: (1) performing a literature survey of candidate power spectrum computational techniques, determining the computational requirements, and formulating a mathematical model satisfying these requirements; (2) implementing the model on UNIVAC 1230 digital computer as the Spectral Analysis Program (SAP); and (3) developing the hardware specifications for a data acquisition system which will acquire an input modulating signal for SAP. The SAP computational technique uses extended fast Fourier transform and represents a generalized approach for simple and complex modulating signals.

Hayden, W. L.

Spectral analysis program. Volume 1: User's guide

The spectral analysis program (SAP) was developed to provide the Manned Spacecraft Center with the capability of computing the power spectrum of a phase or frequency modulated high frequency carrier wave. Previous power spectrum computational techniques were restricted to relatively simple modulating signals because of excessive computational time, even on a high speed digital computer. The present technique uses the recently developed extended fast Fourier transform and represents a generalized approach for simple and complex modulating signals. The present technique is especially convenient for implementation of a variety of low-pass filters for the modulating signal and bandpass filters for the modulated signal.

Hayden, W. L.