Accession Number : AD0784817

Title :   The Weighted Least Squares with Constraint Parameters as Applied to Circular and Hyperbolic Positioning.

Descriptive Note : Technical rept.,

Corporate Author : ROME AIR DEVELOPMENT CENTER GRIFFISS AFB NY

Personal Author(s) : Ellis, George A. ; Thomas, Windsor S.

Report Date : JUN 1974

Pagination or Media Count : 109

Abstract : An evaluation of the performance of circular (Range-Only) and hyperbolic (Range-Difference) position location systems was undertaken with respect to accuracy in the location of a cooperative or uncooperative ground-based emitter and the parameters which affect it. The system performance was evaluated using the Weighted Least Squares Adjustment with Constraint Parameters. The matrix representation of this technique was programmed for the RADC TTS/645. In the circular system a 15.3% improvement in the Distance Measuring Equipment (DME) emitter's positional accuracy was noted when the number of Relay Aircraft (A/C) range measurements increased from two to six. In the hyperbolic system, the emitter could be located to within a standard deviation of 140 feet when the range propagation error was 15 Parts Per Million (PPM). There was no need for the three A/C to maintain a synchronous pattern if the radii of the circles which the aircraft are flying are less than 15 NM. Employing the above-mentioned statistical analysis, the merits of each system (the Range-Only and Range-Difference measurement techniques) were independently evaluated within the confines of a specified scenario. In addition, the computational program may easily and readily be modified to encompass a specific system employing these measurement techniques. (Author)

Descriptors :   *POSITION(LOCATION), ERRORS, POSITION FINDING, DISTANCE MEASURING EQUIPMENT, LEAST SQUARES METHOD, SYSTEMS ANALYSIS, COMPUTER PROGRAMS.

Subject Categories : Target Direction, Range and Position Finding

Distribution Statement : APPROVED FOR PUBLIC RELEASE