How to realize high gain and lowSLL on microstrip antenna?

[gw_uestc]

Is it impossible,using mm-wave microstrip array, to implement <=1.5 degree and <=-20dB SLL?
if it is ,and how to do ?
and Can some one give me some help or refference example?

Best regard!

 

[rajesh_elex]

Re: How to realize high gain and lowSLL on microstrip antenn

For low side lobe level, you must use aperture or proximty coupling. Put the feed network for your array on a different layer than the radiating patches.

Microstrip antennas by D M Pozar is a good collection of papers in microstrip design.

 

[Azulykit]

Re: How to realize high gain and lowSLL on microstrip antenn

Hello,

You don't mention the shape of the array. A circular array will tend to have a lower SLL and you may consider tapering the amplitude illumination to further reduce the SLL. This will broaden the main beam so the overall sise may need to increase to narrow the beamwidth. I would review Kraus, Silver, Jasik and Hansen's books on the subject.

Good Luck

 

[juppydu]

Re: How to realize high gain and lowSLL on microstrip antenn

why not look at
h**p://web.tiscali.it/antenna_software/index.html for linear array synthesis ?

 

[nazanin]

Re: How to realize high gain and lowSLL on microstrip antenn

Is it impossible,using mm-wave microstrip array, to implement <=1.5 degree and <=-20dB SLL?
if it is ,and how to do ?
and Can some one give me some help or refference example?

Best regard!

for enhancement gain must use from array patch antenna.

 

[ghb]

are you looking for 1.5 3 dB beamwidth? if so you will probably run into an issue feeding so many elements in a typical mpa setup. the feeding arrangment must also be carefully thought of when trying to keep sll to a minimum (as mentioned above)

as far as reduced sll, i agree with azulykit. typically sll can be reduced with a tapered apeture distribution. as far as -20db .. this seems a bit aggressive, but i can't say if not achievable or not.

 

[Azulykit]

Re: How to realize high gain and lowSLL on microstrip antenn

Take a look at S. Silver, "Microwave Antenna Theory and Design" figures 6.1 Rectangular apertures and figure 6.2 for circular apertures. There is nothing really fancy going on here and you can see SLL below the -20 dB you need.

I would be more concerned about the 1.5 degree beamwidth. Is that in both planes? If so you are looking for an antenna with gain around 40 dBi and it will not be small.

The easiest way to get into that gain realm is with a reflector and if low SLL is an important issue you might want to consider an offset feed. Just an alternative to the microstrip array you are considering.