How to reduce the first sidelobe level of microstrip antenna array

hello
best for all


I designed a 2X2 microstrip antenna array but the first sidelobe level was very high and the gain of the array was about 13 db.(I have attached hfss file)

1-its side lobe level is too high
How I can reduce the dide lobe level


2- there is multi gain method in hfssT which one is the gain that we measure in real antenna test
3- is there any method too measure sidelobe level in hfss?

thanks

no one want to answer me?

how much is high the side lobe, please attach a jpg of the beam

Hi

I did not look in the file but decreasing SLL is usually achieved by tapering the amplitude of the array factors.

One way to reduce side / back lobes are by fine tuning the reflectors' angles and sizes. (basically the ground plane has to be modified to get the most appropriate results).

You could also use a coupler alongwith the antenna to reduce side lobes or even completely remove the sidelobes !

You may use absorbers around the antenna and fine tune the same so that you achieve as low SLL though they are expensive as compared to the above methods.

I think that 2x2 array is a very small array and the first side lobe is essentially a "grating lobe", that according to your inter-element spacing is more or less inside the visible space, thus at array factor level you cannot do anything ! The only thing is acting on the radiating element pattern that finely tuned can reduce the grating lobe.

Placing your elements closer together will help. try it!