how substrate reduce antenna size

hi all,

I deal with design an on-chip patch antenna (20GHz) for an array antenna. However, I'd like to reduce its size (not use traditional patch antenna shape anymore).

Could you please suggest me some methods to reduce patch antenna size?

Thanks so much

Use high DK substrate

Hi,

First you can use a dielectric substrate with higer epsilon.

or you can use another techniques such as fractal antennas.

Hi,
well increase in dielectric strength is a solution, but u need to optimize with bandwidth requirement. higher epsilon lesser BW and also low radiation efficiency.

Irfan

Yes , I agree with you, using high epsilon material will reduce the size but it will decrease the directivity of the antenna because it propotional to the antenna effctive area.

thanks all of you.

Agree that high epsilon material will reduce the size but decrease antenna directivity.

However, I will design on-chip antenna, so impossible to change the epsilon. What I mean is the shape of antenna.

I already try to connect a ground via at the antenna corner to reduce 1/4 size. Is there any other methods ?

Fractal antenna is another solution I think.

add slits or slots to the antenna, make electric current longer.

Edmund

use meandering instead regular shapes

thanks for all of your reply.
I used meandering to make electric current longer and it works. :)

u find the answer but u can use the mtm higp (high impedance ground plane ) for reduce the antenna size and take much gain ,propagete far away

I research this topic ,ı have source but need further application for my thesis

@iceman13: do you research on onchip patch antenna?
I'm dealing with onchip patch antenna for array antenna controller purpose. I just focus on the controller circuit and that why I'm not good at antenna design. If possible, we can discuss for exchange our applicaions together.

ok well not controller circuit just aspecially HIGP design and varyous antenna type which perfecy match with higp.

the best antenna close to a patch is the annular ring (also called loop) antenna. patch antenna resonates at λ/2 distance. for loop antenna this is approximately λ/4.

if you make the width of the transmission line in loop antenna narrow, you can make its size smaller and smaller (since the currents flow approximately from the middle of transmission line).

if you make the width larger, it is better for bandwidth. in the limit, as the width increases, the loop antenna would behave like a patch.

you can think of meandering as making the loop longer and longer. the problem is, as you meander more and more, in a compact space, the transmission lines couple to each other. also bandwidth is usually small. and of course, currents usually cancel each other resulting in lower gains.

Hi, I know its been very long but by meandering, you increase the loops of your antenna? Did the antenna increase in length as well? So far I've increased the substrate of my antenna but i didn't get a big reduce in the size. Thanks.