23 dBi gain patch panel antenna
According to literature, a 4x4 or 5x5 patch antenna array can achieve similar gain numbers.
But make sure to use a very low loss substrate. On standard FR4, you will never reach such gain because larger arrays then mean larger distribution networks, and the loss in the distribution network will become excessive on FR4.
can you please give an example or some reference?
To get this relative high gain with an antenna array at 2.4GHz you may need many days (or maybe weeks) of research and simulations using expensive EM simulators. Would be even harder if you don't have much experience in this domain.
But if you just need an antenna to use, and don't need to learn how to make it, maybe it worth to buy a cheap (S10) Yagi antenna made for this band:
https://www.aliexpress.com/item/4000...chweb201603_53
The gain may not be 25dBi but for S10 you get more dB's than you expect.
There are numerous antenna types to consider. One easy way is a prime focus parabolic reflector. Gains from 20 dBi to 40 dBi and above are often seen given sufficient space. A horn is another possibility although it would be on the high (large) size of what is usually done.
A yagi-uda array might also be a suitable solution. You might even find examples in the ARRL and "Microwaves101" sites.
Keep in mind that gain and size are directly related.
If you really have to have a patch array there may be suitable commercial versions available. That would not be my first choice because of the associated design complexity but the situation might dictate that path. Again, gain and size are directly related.