1. Improved aperture-coupled microstrip antenna
By Mohamed Morsy

2. Aperture coupled antenna

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

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

5. Radiation Pattern

6. Radiation pattern after increasing the aperture’s length

7. After adding metal sheet at the bottom substrate

8. Radiation pattern after adjusting the stub

9. Radiation pattern after adding metal sheet at the substrate and adjusting the stub match

10. S11

11. conclusion
Using coplanar patch antenna is not a good choice in case of aperture coupled microstrip patch antenna
although it has low radiation loss, less dispersion and high efficiency it will act as a reflector to the aperture slot radiation which radiates on both sides of the ground plane resulting in huge amount of back radiation that destroys the antenna functionality
Depending only on stacked slot coupled antenna will give better results in terms of radiation pattern

12. Future work Using new innovation of aperture coupled microstrip antenna that gives better radiation pattern

13. THANKS
Merry-Christmas
Questions?