Radar system for aircraft

• US 20090174590A1
• Filed: 05/31/2006
• Published: 07/09/2009
• Est. Priority Date: 06/01/2005
• Status: Active Grant

• Current Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Original Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Inventors: Van Gent, Ronald Nikola Huib Willem, Huizing, Albert Gezinus
• Granted Patent: US 8,184,037 B2
• Time in Patent Office: Days
• US Class Current: 342/27
• CPC Class Codes: G01S 13/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G01S 13/426 Scanning radar, e.g. 3D radar G01S13/66 takes precedence
• CPC Class Codes: G01S 13/52 Discriminating between fixed and moving objects or between objects moving at different speeds
• CPC Class Codes: G01S 13/536 using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves
• CPC Class Codes: G01S 13/56 for presence detection presence detection using near field arrangements G01V3/00, e.g. G01V3/08, G01V3/12; burglar, theft or intruder alarms with electrical actuation G08B13/22 - G08B13/26
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/72 for two-dimensional tracking, e.g. combination of angle and range tracking, track-while-scan radar
• CPC Class Codes: G01S 13/933 of aircraft or spacecraft
• CPC Class Codes: G01S 2013/0245 Radar with phased array antenna
• CPC Class Codes: H01Q 21/061 Two dimensional planar arrays
• CPC Class Codes: H01Q 21/20 the units being spaced along or adjacent to a curvilinear path slotted waveguide arrays H01Q21/005; circularly or helically slotted waveguides H01Q21/0062

Abstract

Radar system for providing an aircraft with a facility for in use at least detecting another aircraft in at least one monitorable zone within a region surrounding of that aircraft, wherein the system comprises for each monitorable zone at least one subsystem comprising one transmitter for sending an electro-magnetic probe signal and at least one receiver for receiving a reflection of that probe signal, wherein the transmitter is arranged to send the probe signal in a direction that is static with respect to that aircraft.

Claims

1. Radar system for an aircraft for in use at least detecting another airborne object within a region surrounding the aircraft, wherein the system comprises at least one subsystem comprising:

at least one transmitter for transmitting an electromagnetic probe signal;

a phased array of receivers for simultaneously receiving reflections of the transmitted probe signal and for generating receiving signals which each represent a received reflection of the probe signal; and

a signal processing unit for processing each of the receiving signals for obtaining information about a detected airborne object within the region surrounding the aircraft, wherein the subsystem is arranged to transmit by means of the transmitter the probe signal such that the probe signal covers a zone of interest which is static with respect to the aircraft and wherein the subsystem is arranged to detect by means of the phased array of receivers and the signal processing means an airborne object in the zone of interest.

2. Radar system according to claim 1, wherein the subsystem is arranged to transmit the probe signal such that the probe signal continuously covers the zone of interest.

3. Radar system according to claim 1, wherein the signal processing unit is arranged to determine a direction relative to the aircraft, from which direction the received reflection of the probe signal originates, irrespective of the position of the detected airborne object within the zone of interest so that the zone of interest is observed as a whole.

4. Radar system according to claim 1, the signal processing unit is arranged to determine the direction relative to the aircraft, from which direction the received reflection originates, while the receivers and/or the signal processing unit refrain from scanning the zone of interest so that the zone of interest is observed as a whole.

5. Radar system according to claim 1, wherein the signal processing unit is arranged to use digital multiple beam forming for determining the direction relative to the aircraft, from which direction the received reflection originates.

6. Radar system according to claim 1, wherein the signal processing unit is arranged to perform a Fast Fourier Transform on a receiving signal for forming digital multiple beams.

7. Radar system according to claim 1, wherein the direction of the probe signal is static relative to the aircraft.

8. Radar system according to claim 1, wherein the signal processing means are arranged for obtaining information of a direction of a detected airborne object relative to the aircraft in at least one dimension.

9. Radar system according to claim 8, wherein the signal processing means are arranged for obtaining information of a direction of a detected airborne device relative to the aircraft in at least two dimensions.

10. Radar system according to claim 1, wherein the at least one subsystem is arranged to transmit the probe signal having a constant frequency.

11. Radar system according to claim 1, wherein the at least one subsystem is arranged to transmit the probe signal having a Frequency Modulated Continuous Wave (FMCW).

12. Radar system according to claim 11, wherein the signal processing means are arranged to determine a position of a detected airborne object relative to the aircraft.

13. Radar system according to claim 1, wherein the signal processing means are arranged for obtaining information about a velocity of a detected airborne object relative to the aircraft on the basis of doppler information in the reflections of the probe signal.

14. Radar system according to claim 1, wherein the transmitter of the at least one subsystem comprises a solid state transmitter.

15. Radar system according to claim 1, wherein each receiver of the at least one subsystem comprises a single-chip receiver.

16. Radar system according to claim 1, wherein the at least one subsystem is arranged such that in a first mode at least a probe signal having a constant frequency is transmitted and in a second mode at least a probe signal having a Frequency Modulated Continuous Wave is transmitted.

17. Radar system according to claim 16, wherein the subsystem is arranged such that if in the first mode an airborne object is detected, the airborne object is further detected in the second mode.

18. Radar system according to claim 17, wherein the subsystem is arranged such that if in the first mode an airborne object is detected which approaches the aircraft, the airborne object is further detected in the second mode to switch from the first mode to the second mode.

19. Radar system according to claim 11, wherein the at least one subsystem is arranged to transmit the probe signal comprising the Frequency Modulated Continuous Wave wherein the Frequency Modulated Continuous Wave comprises a frequency pattern which repeats itself in time.

20. Radar system according to claim 1, wherein the radar system comprises a plurality of subsystems for monitoring a first zone in front of the aircraft and at least a second zone that is either behind the aircraft, above the aircraft, or below the aircraft.

21. Aircraft, in particular an unmanned aircraft, provided with a radar system according to claim 1.

22. Radar system according to claim 12, wherein the at least one subsystem is arranged to transmit the probe signal comprising the Frequency Modulated Continuous Wave wherein the Frequency Modulated Continuous Wave comprises a frequency pattern which repeats itself in time.

23. Radar system according to claim 16, wherein the at least one subsystem is arranged to transmit the probe signal comprising the Frequency Modulated Continuous Wave wherein the Frequency Modulated Continuous Wave comprises a frequency pattern which repeats itself in time.

24. Radar system according to claim 17, wherein the at least one subsystem is arranged to transmit the probe signal comprising the Frequency Modulated Continuous Wave wherein the Frequency Modulated Continuous Wave comprises a frequency pattern which repeats itself in time.