need help in desigining microstrip antenna.

[vishal_sonam]

Hello.
I need to design microstrip antenna with these dimensions 60.6mm x 55.5mm on FR4 and my requirements are gain and directivity should be higher than 6dBi and efficiencies should be higher than 90 %, the feed can be microstrip or coaxial.
i have used microstrip line feeding but i m not getting gain and directivity higher than 6 dBi,
so please somebody help me
i will be very thankful to you.
regards

 

[volker_muehlhaus]

on FR4 and my requirements are gain and directivity should be higher than 6dBi and efficiencies should be higher than 90 %

This is physically not possible.

 

[vishal_sonam]

why not possible?
please kindly give me the reason.
thanks

 

[volker_muehlhaus]

why not possible?

The gain of path antennas is limited by physics.
In addition, using FR4 substrate reduces gain because of high dielectric losses in the substrate.

 

[vishal_sonam]

can you elaborate more about physics, actually i m gaining my knowledge in antenna so i need the logic behind everything.
because practical knowledge about the tools is not enough and i think i should have theoretical knowledge about the antenna.

 

[volker_muehlhaus]

Why don't you get a good antenna book first, before starting simulations?
This way, you can learn what you can expect from the different antenna types.