HIGH-RESOLUTION SYNTHETIC APERTURE RADAR DEVICE AND ANTENNA FOR ONE SUCH RADAR

• US 20090079621A1
• Filed: 12/20/2006
• Published: 03/26/2009
• Est. Priority Date: 12/23/2005
• Status: Active Grant

• Current Assignee: Airbus Defence and Space GmbH
• Original Assignee: Astrium GmbH (Airbus SE)
• Inventors: Schaefer, Christoph, Grafmueller, Bernhard
• Granted Patent: US 8,013,778 B2
• Time in Patent Office: Days
• US Class Current: 342/25.A
• CPC Class Codes: G01S 13/904 SAR modes
• CPC Class Codes: G01S 13/9058 Bistatic or multistatic SAR

Abstract

The invention relates to a high-resolution synthetic aperture radar device (10) comprising at least one transmitting antenna (TX1-TX3) for producing and emitting radar pulses for scanning an object (12), a receiving antenna (14) for receiving the radar beams (20, 22, 24) emitted and reflected by an object, wherein the receiving antenna (14) has several sub-apertures (RX1-RX17) arranged along elevation, which form a minimum of azimuth apertures, wherein the high-resolution synthetic aperture radar device is embodied such that pulse signals (18) are emitted at irregular time intervals.

Claims

1-18. -18. (canceled)

19. A high-resolution synthetic aperture radar device comprising:

at least one transmitting antenna for producing radar beams for scanning an object;

a receiving antenna for receiving radar beams reflected by the object, the receiving antenna comprising several sub-apertures arranged in elevation,

wherein the radar beams include pulse signals emitted at irregular time intervals.

20. The high-resolution synthetic aperture radar device according to claim 19, wherein the sub-apertures are arranged to form fewer azimuth apertures than a high resolution wide swath synthetic aperture radar.

21. The high-resolution synthetic aperture radar device according to claim 19, further comprising a processor structured and arranged to process received radar echoes in azimuth with a resampling method.

22. The high-resolution synthetic aperture radar device according to claim 19, wherein the at least one transmitting antenna comprises at least two transmitting antennas operated simultaneously in a frequency multiplex.

23. The high-resolution synthetic aperture radar device according to claim 21, further comprising one respective receiving channel for each of the radar echoes.

24. The high-resolution synthetic aperture radar device according to claim 23, wherein the radar echoes in each respective receiving channel is processed by digital beam forming.

25. The high-resolution synthetic aperture radar device according to claim 24, wherein the respective receiving channels are structured and arranged to strictly separate a received radar echo from adjacent received radar echoes.

26. The high-resolution synthetic aperture radar device according to claim 25, further comprising a weighting factor unit structured and arranged to provide signals of the sub-apertures in a digital domain with time-dependent complex weighting factors.

27. The high-resolution synthetic aperture radar device according to claim 26, wherein the time-dependent complex weighting factors are formed so that an antenna diagram in the directions of other antenna diagrams obtains a zero.

28. The high-resolution synthetic aperture radar device according to claim 24, further comprising a space-time adaptive processor for the signals of the sub-apertures (RX-RX17).

29. The high-resolution synthetic aperture radar device according to claim 21, further comprising a processor structured and arranged to compress data obtained from the received radar echoes before transmission to a ground station.

30. The high-resolution synthetic aperture radar device according to claim 19, further comprising respectively one transmission module and front end for generating an antenna pattern and emitting a pulse for each of the at least one transmitting antennas.

31. The high-resolution synthetic aperture radar device according to claim 30, wherein the transmission modules and front ends are structured and arranged to emit transmitting chirps coherently and simultaneously.

32. The high-resolution synthetic aperture radar device according to claim 31, wherein each transmission module and front end is structured and arranged to respectively emit in a different frequency range.

33. The high-resolution synthetic aperture radar device according to claim 31, further comprising digital frequency filters to separate in terms of frequency the data streams produced from radar beams received.

34. The high-resolution synthetic aperture radar device comprising:

at least two transmitting antennas for producing radar beams for scanning an object,

wherein the at least two transmitting antennas are simultaneously operable in a frequency multiplex.

35. An antenna for the high-resolution synthetic aperture radar device according to claim 34, wherein

the at least two transmitting antennas are structured and arranged to emit respectively one radar beam in a microwave range;

and

a receiving antenna structured and arranged to receive reflected radar beams in the microwave range, and the receiving antenna in elevation comprising several sub-apertures that form fewer than three azimuth apertures.

36. The antenna according to claim 35, wherein the at least two transmitting antennas are arranged next to one another in elevation.

37. The antenna according to claim 35, wherein the receiving antenna is arranged next to the at least two transmitting antennas in elevation.

38. The antenna according to claim 35, wherein the sub-apertures form exactly one azimuth aperture.

39. The antenna according to claim 35, wherein a height of each sub-aperture in elevation is lower than the height of each transmitting antenna in elevation.

40. A method for a high-resolution synthetic aperture radar device, comprising:

producing radar beams for scanning an object;

receiving radar beams reflected by the object with a receiving antenna comprising several sub-apertures arranged in elevation; and

emitting pulse signals in the produced radar beams at irregular time intervals.