Accession Number : AD0729358

Title :   All-Weather, Low-Level Navigation.

Descriptive Note : Semi-annual rept. no. 3, Oct 70-Apr 71.

Corporate Author : OHIO UNIV ATHENS DEPT OF ELECTRICAL ENGINEERING

Report Date : AUG 1971

Pagination or Media Count : 57

Abstract : During this reporting period a second Rubidium clock stabilized low-frequency transmitting station was mechanized with a phase-locked loop synthesizer to permit a flyable demonstration of a precision all-weather, low-level navigation system using passive, direct-ranging techniques. Phase measurements of the respective transmitter carriers are optimally obtained by means of two maximum likelihood receivers with an onboard clock. A General Automation SPC-12 digital computer provides coordinate conversion to an x-y position format, a route storage capability, and execution of a flight director algorithm. Extension and additions to the theoretical maximum likelihood receiver work provides a comprehensive comparison of this technique with the conversational phase-locked loop for phase estimation purposes. A special display-conventional terminal was designed and fabricated to provide a flexible and useful means of communicating with the SPC-12 computer both in the laboratory and during airborne exercises. Novel time and memory conserving computer software is also discussed. (Author)

Descriptors :   *NAVIGATION COMPUTERS, *ALL WEATHER AVIATION, SYSTEMS ENGINEERING, RADIO RECEIVERS, LOW PASS FILTERS, SIGNAL TO NOISE RATIO, ATOMIC CLOCKS, CIRCUITS, RANGE FINDING, ADAPTIVE CONTROL SYSTEMS, MATHEMATICAL MODELS, TRANSFER FUNCTIONS, DATA STORAGE SYSTEMS.

Subject Categories : Navigation and Guidance
      Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE