METHOD FOR IDENTIFYING A FACILITY ON THE GROUND OR AT SEA

• US 20120050088A1
• Filed: 09/23/2009
• Published: 03/01/2012
• Est. Priority Date: 09/23/2008
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Provost, Claude, Schoendorff, Bertrand
• Granted Patent: US 8,610,618 B2
• Time in Patent Office: Days
• US Class Current: 342/45
• CPC Class Codes: G01S 13/765 with exchange of information between interrogator and responder
• CPC Class Codes: G01S 13/767 Responders; Transponders teaching or practice apparatus for gun-aiming or gun-laying using reflecting targets or active targets F41G3/26
• CPC Class Codes: G01S 13/78 discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe G01S13/75, G01S13/79 take precedence
• CPC Class Codes: G01S 13/781 Secondary Surveillance Radar [SSR] in general

Abstract

The present invention includes a method for identifying a facility on the ground or at sea, the method being implemented on an airborne responder linked to at least two antennas, the method including a step of choosing a first transmission antenna and a step of transmitting an interrogation message from the chosen antenna. The method further includes testing whether a response has been received by the responder, and, if at least one response signal is received by at least one of the antennas, choosing a transmission antenna as a function of the response signal or signals received. If no response message is received, a different transmission antenna is chosen from the antenna that transmitted the last interrogation message. The method is repeated from the step of transmitting the interrogation message.

Claims

1. A method for identifying a facility on the ground or at sea, the method being implemented on an airborne responder linked to at least two antennas, said method comprising:

a step of choosing a first transmission antenna;

a step of transmitting at least one interrogation message from the chosen antenna (104);

testing whether a response signal answering the interrogation message has been received by the responder;

if at least one response signal is received by at least one of the antennas of the responder, identifying the response signal or signals, and choosing a transmission antenna as a function of said response signals received;

if no response signal is received, choosing a different transmission antenna from the antenna that transmitted the last interrogation message (108); and

repeating the method from the step of transmitting the interrogation message or messages.

2. The method of identification as claimed in claim 1, wherein, when at least one response signal has been received by at least one of the antennas of the responder, the transmission antenna chosen is, from among said antennas, that which has led, for the majority of the response signals received, to the best link budget.

3. The method of identification as claimed in claim 1, wherein, during each iteration of the method, a test step is executed to decide whether an interrogation message need or need not still be transmitted.

4. The method of identification as claimed in claim 3, wherein the stopping of the transmission of the interrogation messages is decided by the test step when a fixed number N of messages has already been transmitted.

5. The method of identification as claimed in claim 1, wherein the stopping of the transmission of the interrogation messages is triggered by a clock signal.

6. The method of identification as claimed in claim 1, wherein, when a transmission antenna has been chosen after at least one response signal has been received by at least one of the antennas of the responder, then the transmission antenna is no longer changed until the last interrogation message has been transmitted.

7. The method of identification as claimed in claim 1, wherein the interrogation messages are transmitted from an IFF responder on the frequency dedicated to the transmissions of IFF responses.

8. The method of identification as claimed in claim 1, wherein the interrogation messages are transmitted from an IFF responder on the frequency 1090 MHz.

9. An airborne responder linked to at least two antennas, a first antenna being placed above the fuselage of the aircraft equipped with the responder, the second antenna being placed under said fuselage, the responder implementing the identification method as claimed in claim 1.

10. The responder as claimed in claim 9, wherein the antennas are linked to the responder for transmitting an interrogation message on the frequency 1090 MHz.