Accession Number : AD0720214

Title :   All-Weather, Low-Level Navigation.

Descriptive Note : Semi-annual rept. no. 2, 10 Apr-10 Oct 70.

Corporate Author : OHIO UNIV ATHENS DEPT OF ELECTRICAL ENGINEERING

Report Date : JAN 1971

Pagination or Media Count : 77

Abstract : The results of the successful, initial flight experiments and measurements involving the tuned radio frequency receiver and the maximum likelihood phase estimator of the all-weather, low-level navigation system are given. At low level, 80 miles from the transmitter, 10 degrees (100 feet at 263 KHz) of phase resolution were obtained with received signal levels less than 0.1 microvolt. Short range (4 miles) ground based measurements showed repeatability of one degree (10 feet at 263 KHz) for high received SNR conditions. A digital flight director design has been completed and indications from simulation studies are that it will provide increased capability to minimize error off-course without gyro feedback. Work has been done on programming the SPC-12 for airborne computations. This computer will be used with the receiving components to provide for a complete flyable system. All work is now converging on the goal of providing the government with a flying model which can be operated independent of its creators. With this model the efficacy of a low-level navigation system can be further evaluated. This report also discusses techniques developed for lane counting, narrow band filtering, receiver blanking to minimize spherics effects, frequency synthesis, low-frequency-beacon phase stability measurements and man-machine system considerations. (Author)

Descriptors :   *NAVIGATION COMPUTERS, *ALL WEATHER AVIATION, SYSTEMS ENGINEERING, POSITION FINDING, RANGE FINDING, LOW ALTITUDE, LOW PASS FILTERS, ADAPTIVE CONTROL SYSTEMS, GROUND POSITION INDICATORS, FLIGHT SIMULATORS, RADIO RECEIVERS, DISPLAY SYSTEMS.

Subject Categories : Air Navigation and Guidance

Distribution Statement : APPROVED FOR PUBLIC RELEASE