System for processing directional signals

Abstract

A system for calculating the bearing of a signal source, with a directional antenna, provides corrections for distortion, such as due to a small fuselage of the monitoring aircraft and the elevation angle of an intruder aircraft with respect to the monitoring aircraft. A correction is applied to the bearing estimate that is based on relevant factors, such as the fuselage size and the elevation angle of the intruder aircraft. The correction can be calculated or applied through the use of a look-up table, which may be either pre-selected or selected after calculation of the elevation angle of the intruder aircraft.

Description

[0001] 1. Field of the Invention[0002] The present invention generally relates to processing signals received with a directional antenna, and more particularly, to identifying the bearing of a signal source based on signals received with a directional antenna.[0003] 2. Description of the Related Art[0004] As technology in air transportation has evolved, the demands on the members of the flight deck have become increasingly severe. To avoid flight path conflicts, the flight deck crew monitors considerable aircraft status information for multiple surrounding aircraft at a time when air traffic is dramatically increasing. Higher aircraft speeds magnify the burden by reducing the time in which the flight deck crew can respond to threatening situations.[0005] To assist the flight deck crew and enhance safety, several systems have been and are being developed. Many aircraft carry transponders (e.g., mode S, mode C, mode A) by which one aircraft can communicate to a second aircraft both it...

AI Technical Summary

Problems solved by technology

As technology in air transportation has evolved, the demands on the members of the flight deck have become increasingly severe.

Various factors, however, may degrade the accuracy of the bearing estimate.

For example, monitoring aircraft having small fuselages may detect transponder signals differently than larger aircraft, which may degrade the bearing estimate accuracy.

Consequently, the model illustrated in FIG. 2 is not as accurate with aircraft that have small fuselages, such as those aircraft with a radius of fuselage curvature smaller than 64 inches.

This displacement may degrade the accuracy of the bearing estimate.

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