L/C Dual-Band Dual-Polarized Shared Aperture Array

1. L/C Dual-Band Dual-PolarizedShared Aperture Array COMP 901 / ITEC 810 Final Report Author: Zhu SUN (42251087) Supervisor: Prof. Karu Esselle Date: 13/06/2012

2. Outline Introduction Theoretical Analysis L/C-DBDP Half Perforated Unit Cell L/C-DBDP Overlapped Unit Cell L/C-DBDP Half Perforated Full Array Conclusion

3. Introduction--Background Fig.2 Space- & Air-Borne case Fig.1 Base station antenna

4. Introduction--Literature Review Fig.4 Overlapped Structure [2] Fig.3 Perforated Patch [1] Fig.5 Interleaved Structure [3] • L. L. Shafai, W. A. Chamma, M. Barakat, P. C. Strickland, and G. Séguin, “Dual-band dual-polarized perforated microstrip antennas for SAR applications”, IEEE Trans. Antennas Propagat., vol. 48, no. 1, pp.58-66, Jan. 2000. • M. Moghaddam, et al, “A Dual Polarized UHF/VHF Honeycomb Stacked-Patch Feed Array for a Large-Aperture Space-borne Radar Antenna”, Aerospace Conf. 2007, pp.1-10 • X. Qu, S.S. Zhong, Y.M. Zhang and W. Wang, “Design of an S/X dual-band dual-polarised microstrip antenna array for SAR applications”, IET Microw. Antennas Propag., vol.1, no.2, pp. 513–517, 2007.

5. Theoretical Analysis--expression explanation (I) Fig.6 Field Distribution & Equivalent M-current

6. Theoretical Analysis--expression explanation (II) • Perforation has similar effect as shorten radiation edge • From Transmission Line Model, equivalent circuit parameters [4] can be written as: • ; Q factor can be expressed as: , where Conclusion: bandwidth scales with radiation edge width 4. H.Pues, etal, “Accurate transmission-line model for the rectangular microstrip antenna”, Microwaves, Optics and Antennas, IEE Proceedings H, vol.131, no.6, pp.334-340

7. Theoretical Analysis--simulation result (I) Non-Perforated Half-Perforated Fully-Perforated Fig.7 Comparison of three structures

8. Theoretical Analysis--simulation result (II) • Bandwidth decreases with the increase of perforations Fig.8 Simulated bandwidth of three structures

9. L/C-DBDP Half Perforated Unit Cell--Configuration • Reduce Perforation Number • Lower Profile • Trade off in Bandwidth • Moderate Complexity Fig.9 Configuration of “half-perforated” unit cell

10. L/C-DBDP Half Perforated Unit Cell--Inter-band Coupling Fig.10 coupling from C element to L element Fig.11 coupling from L element to C element

11. L/C-DBDP Half Perforated Unit Cell--Fabrication & Measurement Top View Bottom View Fig.13 Antenna Under Measurement Side View Fig.12 Fabricated Half-Perforated Unit Cell

12. L/C-DBDP Half Perforated Unit Cell--Measurement Results (I) VSWR VSWR VSWR Isolation Isolation Fig.14 L band Measured Port Parameters Fig.14 L band Measured Port Parameters Fig.14 L band Measured Port Parameters

13. L/C-DBDP Half Perforated Unit Cell--Measurement Results (II) Fig.15 L band Measured Radiation Pattern

14. L/C-DBDP Half Perforated Unit Cell--Measurement Results (III) VSWR VSWR VSWR Isolation Isolation Fig.16 C band Measured Port Parameters Fig.16 C band Measured Port Parameters Fig.16 C band Measured Port Parameters

15. L/C-DBDP Half Perforated Unit Cell--Measurement Results (IV) Fig.17 C band Measured Radiation Pattern

16. L/C-DBDP Overlapped Unit Cell--Configuration (I) Fig.18 Configuration of “overlapped” unit cell

17. L/C-DBDP Overlapped Unit Cell--Configuration (II) Fig.19 Vertical transfer method

18. L/C-DBDP Overlapped Unit Cell--Fabrication & Measurement Fig.20 Fabricated Overlapped Unit Cell

19. L/C-DBDP Overlapped Unit Cell--Measurement Results (I) S Parameters S Parameters Radiation Pattern Radiation Pattern Fig.21 L band Measured Results

20. L/C-DBDP Overlapped Unit Cell--Measurement Results (II) S Parameters Radiation Pattern Fig.22 C band Measured Results

21. L/C-DBDP Unit Cell--Measured Data Conclusion Table I. Measured results of L/C DBDP unit cell

22. L/C-DBDP Half Perforated Full Array--Sidelobe Level Calibration Perspective View Side View Simulated Radiation Pattern Fig.23 Raised Ground & SLL Calibration

23. L/C-DBDP Half Perforated Full Array--Configuration Perspective View Top View Fig.24 Configuration of Half Perforated Full Array

24. L/C-DBDP Half Perforated Full Array--Simulated Results L band C band Fig.25 Simulated S-Parameters of full array

25. L band cavity SMA via hole Metal Perturbation with via hole SMA connector L/C-DBDP Half Perforated Full Array--Layout (I) Aluminum Plate Upper Surface Aluminum Plate downside

26. L/C-DBDP Half Perforated Full Array--Layout (II) L driven patch & C driven patch C Parasitic Patch

27. L/C-DBDP Half Perforated Full Array--Layout (III) L Perforated Parasitic Patch

28. Conclusion • Theoretically explain relationship between bandwidth and perforation • Design and fabricate a L/C “half perforated” unit cell • Design and fabricate a L/C “overlapped” unit cell • An L/C “half perforated” full array is designed and under fabrication

29. Q & A Thanks !