This is a 2 × 2 patch antenna array designed for 2.425 GHz. It can be manufactured on a standard two-layer PCB using 1.6 mm thick FR-4.

One challenge is the relatively large variation in the dielectric constant of FR-4, typically between 4.2 and 4.8. This makes it difficult to predict the exact resonant frequency. For this reason, the project includes several slightly different versions that can be fabricated and tested to find the best match for the target frequency.

Files for simulation, PCB design, and manufacturing-ready Gerber files are included.