Accession Number:

ADA010112

Title:

Experimental Validation of PALM - A System for Precise Aircraft Location

Descriptive Note:

Technical note

Corporate Author:

MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Report Date:

1975-04-29

Pagination or Media Count:

120.0

Abstract:

A ground based system to precisely locate aircraft in three dimensions based on transponder replies has been designed. Field tests have been conducted to validate the design of the elevation performance. This document reports on the principle of operation, experimental hardware and field test of the Precision Altitude and Landing Monitor PALM. The key features incorporated in the PALM design include a no new avionics required, i.e., uses standard aircraft transponder b high accuracy position data, i.e., a 1- mrad 0.06 degrees rms error in elevation and in azimuth c broad airspace coverage, e.g., 40 degrees in elevation, 120 degrees in azimuth expandable to 360 degrees and several 10s of miles in range and d low life cycle equipment cost. The high accuracy in the difficult airport multipath environment is a direct result of a a newly developed antenna synthesis procedure, b the development of adaptive multipath suppression techniques, and c the use of digital signal processing. The program, to date, has focused on an experimental evaluation of the elevation performance. The electronics required for the tests have been built into a self-powered van to facilitate experiments at remote airports. The actual flight test data demonstrated experimental errors on the order of 1 mrad moreover, as predicted by theory, the resulting errors were essentially independent of elevation angle. Potential applications for the PALM position data include parallel approach monitoring, independent altitude monitoring, andor performance assurance monitoring of landing guidance systems.

Subject Categories:

  • Air Navigation and Guidance

Distribution Statement:

APPROVED FOR PUBLIC RELEASE