Patent ID: 9047764
Filing Date: 2015-06-02
Classification: G08G

Abstract:
1. A method of alert calculation for an aircraft obstruction proximity warning system comprising: a step for detecting a hazardous flight situation capable of triggering an alert in a reactive mode, by analyzing a change of a current radio altitude signal measuring a distance between an aircraft and a nearest element situated beneath the aircraft, as a function of time during flight, and generating an alert when said change is considered abnormal, further comprising, prior to the step of detection, converting a first raw radio altitude signal into a second radio altitude signal which is used as an input signal by said step of detecting, said step of converting comprising frequency filtering of said first raw radio signal altitude in order to reduce an influence of obstacles on the radio altitude signal, said frequency filtering being defined by at least two filtering parameters: a gain parameter and a cut-off frequency, and said filtering parameters being calculated as a function of at least one parameter selected from the group consisting of type of aircraft mission, density of obstacles around the aircraft, and average speed of the aircraft over a brief period preceding an instantaneous time.