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

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

Introduction --Background Improve payload efficiency in space- and air-borne cases; ease the deployment and maintainance Fig.2 Space- & Air-Borne case Fig.1 Base station antenna

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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

L/C-DBDP Unit Cell --Measured Data Conclusion Table I. Measured results of L/C DBDP unit cell specification Overlapped Structure Half Perforated Structure L band (1.25GHz) C band (5.3GHz) Bandwidth (MHz) 219 790 166 802 Bandwidth (%) 17.6 15 13 15.8 polarization Dual-linear polar Isolation (dB) 17 19 21 X polarization (dB) -23 -25 -30 Gain (dB) 9.9 13.4 9.7 10.3 1st SLL (dB) -- -15(E) / -21(H) -5(E) / -13(H)

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

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

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

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

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

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

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

Q & A Thanks !