Bearing detection system
First Claim
1. A bearing detection system having at its detection end a directional antenna comprising three radially extending directional antenna elements arranged at a 120°
- angle to each other and defining therebetween three directional antenna sectors, the detection system having means for making amplitude comparison of receiving signals received by said three directional antenna elements and forming a three bit truth table formed by the strength of the three receiving signals against six directions including the three directions of the antenna elements and the three directions of the sectors between said antenna elements, wherein in the truth table the signal values corresponding to 000 and 111 are made as undetectable.
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Accused Products
Abstract
A bearing detection system used in an Airborne Collision Avoidance System. The detection end of the system is formed as a directional antenna having 3 directional antenna elements extending radially at a 120° angle with each other. The antenna element has an actual length corresponding to λ/8, wherein λ is the wavelength of the receiving wave, but the element has an effective length corresponding to λ/4 by the provision of an impedance matching plate and a back lobe suppression plate. Bearings of the incoming wave can be detected by means of relative strength of the receiving signal levels of the three antenna elements obtained by amplitude comparison and by forming 3 bit truth table for six directions including the 3 directions of the antenna and 3 boundary directions thereof by the strength of the receiving signal received by the three antenna elements.
12 Citations
5 Claims
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1. A bearing detection system having at its detection end a directional antenna comprising three radially extending directional antenna elements arranged at a 120°
- angle to each other and defining therebetween three directional antenna sectors, the detection system having means for making amplitude comparison of receiving signals received by said three directional antenna elements and forming a three bit truth table formed by the strength of the three receiving signals against six directions including the three directions of the antenna elements and the three directions of the sectors between said antenna elements, wherein in the truth table the signal values corresponding to 000 and 111 are made as undetectable.
- View Dependent Claims (2, 3, 4, 5)
Specification