1. Junjie Wu, Jianyu Yang, et.al. Univ. of Electro. Sci. & Tech. of China
First Result of Bistatic Forward-looking SAR with Stationary Transmitter
Junjie Wu, Jianyu Yang, et.al.
Univ. of Electro. Sci. & Tech. of China

2. Contents Introduction System Setup
Experimental result of stationary transmitter BFSAR
Current work

3. May, 12th, Sichuan
Mar, 11th, Tohuku

4. 1.Introduction Forward-looking Backward-looking Squint-looking
Side-looking
Squint-looking
Backward-looking

5. 1.Introduction Forward-looking radar imaging： Obstruction warning
Scene matching guidance
Self-landing
Self-navigation
Materials and/or troop dropping
Forward looking radar
Forward Squint SAR
Forward Squint SAR
Boresight SAR
Boresight SAR

6. Why can not SAR work in forward-looking mode?
1.Introduction
Why can not SAR work in forward-looking mode?

7. Monostatic SAR Iso-range and Iso-Doppler lines
1.Introduction
SAR imaging conditions：
Iso-range and Iso-Doppler lines —
there is enough separation angle----2D resolution
sole intersection----No ambiguity
Monostatic SAR Iso-range and Iso-Doppler lines
Monostatic SAR imaging area：
Iso-range and Iso-Doppler lines are orthogonal
Sole intersection

8. Monostatic SAR Iso-range and Iso-Doppler lines
1.Introduction
Monostatic SAR forward-looking area：
Iso-range and Iso-Doppler lines are parallel
Double intersections
Monostatic SAR Iso-range and Iso-Doppler lines
Monostatic SAR：can not image the forward-looking area

9. Separate the transmitter and receiver
1.Introduction
What can we do?
Separate the transmitter and receiver
Bistatic

10. Bistatic SAR Iso-range and Iso-Doppler lines
1.Introduction
Bistatic SAR forward-looking area：
Iso-range and Iso-Doppler lines are not parallel
Sole intersections
Bistatic SAR Iso-range and Iso-Doppler lines
Bistatic SAR：
can image the forward-looking area of the receive station

11. 1.Introduction BFSAR with two moving platforms
Transmitter Side-looking or Squint
Receiver forward-looking
Transmitter
Side-looking
Spaceborne transmitter——Airborne receiver
Airborne transmitter——Airborne receiver
Receiver
Forward-looking
Reconnaissance
Self-navigation
Air-drop

12. Spaceborne transmitter side-looking Airborne receiver backward-looking
1.Introduction
BFSAR
FGAN-Germany
Spaceborne/airborne bistatic backward-looking experiment ( )
Spaceborne transmitter side-looking
Resolution：1-3m Area: 3×5km
Airborne receiver backward-looking

13. 1.Introduction Stationary Transmitter (ST) BFSAR
Transmitter----high tower, mountain, geostationary satellite, stratosphere low speed airship…
Receiver----airborne
Forward-looking Receiver
Reconnaissance
Self-navigation
Air-drop

14. 1.Introduction (a) monostatic FSAR (b) ST-BFSAR
Imaging principle of ST-BFSAR
(a) monostatic FSAR
(b) ST-BFSAR

15. 2.System Setup target Vector Signal Generator Agilent 8267D
Stationary Transmitter
Vector Signal Generator
Agilent 8267D
target
Vehicle-borne Moving Receiver
Wideband signal receiver

16. 2.System Setup Carrier Frequency: 9.6GHz Bandwidth: 80MHz PRF: 500Hz
System parameters
Carrier Frequency: 9.6GHz
Bandwidth: 80MHz
PRF: 500Hz
Pulse Width: 20us
Receiver velocity: 7m/s

17. Upward forward-looking Downward forward-looking
2.System Setup
Downward-looking angle is too small
Target
Upward forward-looking
Downward forward-looking
Equivalent

18. 2.System Setup

19. 3. Experimental results
Slow time domain
Doppler domain

20. Imaging result of ST-BFSAR
3. Experimental results
Imaging result of ST-BFSAR

21. 4.Current Work A A A A C O O O C O B B B
2D spatial variance

22. Keystone-based azimuth nonlinear Chirp Scaling imaging algorithm
4.Current Work
Keystone-based azimuth nonlinear Chirp Scaling imaging algorithm
Keystone transform:
Correct the linear range walk of all targets
----remove the variance of range migration
NLCS:
Equalize the FM rates of all targets
---- remove the variance of azimuth FM rate

23. Thank you