Publications
A laser system for detecting shipping in the approach zone at Logan Airport
Summary
Summary
Runway 4-R at Logan Airport cannot now be used with full effectiveness because of tall ships passing through the runway's approach clearance zone. The key to utilizing the full length of Runway 4-R at Logan Airport for longer periods of time is to establish a channel surveillance system that would...
Transponder Test Program Plan
Summary
Summary
Released to sponsor only
Concept formulation studies of the control aspects of the fourth generation air traffic control system, interim report
Summary
Summary
To develop plans for a viable ATC system over the next 25 years a whole spectrum of studies can be conducted, each concerned with a different time frame. The spectrum, when laid out over time, is bracketed by two extreme cases. 1. One extreme is analysis of the present ATC...
An airborne traffic situation display system
Summary
Summary
An airborne traffic situation display system which could be used as an adjunct to the evolving National Airspace System/Automatic Radar Control Terminal System (NAS/ARTS) is described. In the proposed system, a contemporary realization of an old concept, the NAS/ARTS data are broadcast. A small digital computer in an aircraft then...
A theory of multiple antenna AMTI radar
Summary
Summary
This note presents a detailed mathematical analysis of a multiple-antenna AMTI radar system capable of detecting moving targets over a significantly wider velocity range than is achievable with a single-antenna system. The general system configuration and signaling strategy is defined, and relationships among system and signaling parameters are investigated. A...
Propagation phenomena affecting satellite communications systems operating in the centimeter and millimeter wavelength bands
Summary
Summary
The theories describing the effects of the troposphere on satellite communication systems operating in the microwave region are reviewed. The results of computations based upon the theories and atmospheric models are presented and compared with available experimental data. From the model computations it is seen that rain causes the major...
Radar meteorological applications of automatic film reading
Summary
Summary
The data recording of storm information as detected by a weather radar has been customarily made on photographic film. Research radars and an occasional U. S. Weather Bureau radar are fitted with scope cameras to record the radar plan position indicator (PPI) display. Over the past 15 years a large...
Predictive coding in a homomorphic vocoder
Summary
Summary
Application of a type of predictive coding to the channel signals of a homomorphic vocoder has produced sizable bit rate reductions. With only slight degradation in speech quality, reduction (for the spectral envelope information) from 7800 to 4000 bits/s was achieved. A technique for obtaining the formant frequencies from the...
A cockpit situation display of selected NAS/ARTS data
Summary
Summary
By the mid-1970's, the evolving NAS/ARTS ground environment will provide the air traffic controllers with high quality computer-processed traffic situation displays. We believe it would be useful, particularly in busy terminal areas, to display some of this data in the cockpit. Systems with this objective have been constructed and flight...
Measurement of clear air turbulence in the lower stratosphere using the Millstone Hill L-Band Radar
Summary
Summary
Radar measurements of thin turbulent layers in the clear atmosphere have been extensively reported in the literature and have recently been summarized by Hardy and Katz (1969). The majority of the thin turbulent layer detections reported have been for layers in the lower troposphere. Using the high power radar facilities...