SYNTHETIC APERTURE RADAR SYSTEM

• US 20150160337A1
• Filed: 05/08/2013
• Published: 06/11/2015
• Est. Priority Date: 05/08/2012
• Status: Active Grant

• Current Assignee: Secretary of State For Defence
• Original Assignee: Secretary of State For Defence
• Inventors: Muff, Darren George
• Granted Patent: US 9,696,422 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 13/74 Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
• CPC Class Codes: G01S 13/904 SAR modes
• CPC Class Codes: G01S 13/9058 Bistatic or multistatic SAR

Abstract

The present application is concerned with low cost, and generally broad bandwidth, synthetic aperture radar systems, and methods of producing synthetic aperture radar images.

Claims

1. A synthetic aperture radar system comprising a transmitter, an analogue repeater, and a ground based receiver, wherein:

the ground based receiver comprises an analogue to digital converter,

the transmitter is space-borne or airborne,

the analogue repeater is space-borne or airborne,

the synthetic aperture radar system is a bistatic radar system.

2. The synthetic aperture radar system of claim 1, where the analogue repeater is airborne.

3. The synthetic aperture radar system of claim 2, where the transmitter is space-borne.

4. The synthetic aperture radar system of claim 1 where the analogue repeater is adapted to operate at a frequency of at least 30 GHz, at least 40 GHz or at least 50 GHz.

5. The synthetic aperture radar system of claim 1, where the transmitter is adapted to operate in at least two frequency ranges including a first frequency band around 300 MHz and a second frequency band at at least 35 GHz.

6. The synthetic aperture radar system of claim 1, where the analogue repeater is adapted to operate at the Ka-band.

7. A method of producing a synthetic aperture radar image comprising:

transmitting an analogue signal from a space-borne or airborne transmitter to a surface to be imaged,

reflecting the analogue signal from the surface to a space-borne or airborne analogue repeater,

transmitting the analogue signal from the airborne analogue repeater to a ground based receiver,

converting the analogue signal received by the ground based receiver into a digital signal,

processing the digital signal to create the synthetic aperture radar image, wherein, the method is performed bistatically.

8. The method of producing a synthetic aperture radar image of claim 7, where the analogue repeater is airborne.

9. The method of producing a synthetic aperture radar image of claim 8, where the transmitter is space-borne.

10. The method of producing a synthetic aperture radar image of claim 7, where the analogue repeater operates at a frequency of at least 30 GHz, at least 40 GHz or at least 50 GHz.

11. The method of producing a synthetic aperture radar image of claim 7, where the transmitter is adapted to operate in at least two frequency ranges including a first frequency band around 300 MHz and a second frequency band at at least 35 GHz, and the step of transmitting the analogue signal is performed at at least one of the first and second frequency bands.

12. The method of producing a synthetic aperture radar image of claim 7, where the analogue repeater operates at the Ka-band.

13. The method of producing a synthetic aperture radar image of claim 7, where the step of processing the digital signal includes the step of first transmitting the digital signal across a network.