1. Aperture-coupled Stacked Coplanar Patch Antenna Presented by: Mohamed Morsy Date: October 19,2006

2. Aperture coupled antenna

3. Recent developments related to aperture coupled microstrip antenna Demonstrated impedance bandwidths ranging from 5% to 50% Independent selection of antenna feed substrate material Two layer construction shields radiating aperture from feed network Increased substrate space for antenna elements and feed line Convenient integration for active arrays Theoretically zero cross polarization in principle planes

4. Back radiation and enhanced bandwidth width conflict By coupling the resonant patch to the slot near its resonant will result in increased bandwidth But this technique induces high back radiation The reason is due to the proximity of the resonance of the slot that radiates on both sides of the ground plane

5. Stacked Slot –Coupled Microstrip Antenna In order to overcome that problem we use stacked patches In this case the resonance of the slot is chosen to be far from the resonance of the patch

6. Coplanar Patch Antenna The coplanar waveguide, compared with the microstrip line, has advantages such as low radiation loss, less dispersion, uniplanar configuration

7. Aperture-Coupled Coplanar Patch Antennas CPA has almost the same performance as a MPA, or even better performance, if it is fed by an aperture cut on its background. It is known that the surface wave modes in the substrate have influences on the performances of an aperture-coupled microstrip patch antenna, so we usually hope to suppress the surface wave modes excited in the substrate to improve the performance of an antenna.

8. S11

9. VSWR Bandwidth(10.2GHz-10.7GHz)

10. Radiation efficiency Radiation efficiency=.95

11. Radiation Pattern

12. Stacked slot coupled coplanar patch antenna Side View Top view Є1=6.15, Є2= Є3=2.2

13. S11

14. Radiation Pattern

15. Radiation efficiency Max Radiation efficiency=.962,Peak gain=1.6043,Peak directivity=1.6679

16. Conclusion Using stacked slot coupled printed antennas resolve the conflict between enhanced bandwidth and back radiation Using coplanar patch antenna in addition to stacked coupled layers gives more improvement in terms of low radiation loss and less dispersion Hence increasing antenna efficiency, diving better front to back ratio

17. Future Work Designing(4-bits) integrated phase shifter Constructing aperture-coupled stacked coplanar patch antenna array Building high performance active array antenna

18. THANK YOU QUESTIONS?