Micro strip patch directional antennas are an attractive solution for modern wireless systems due to their high gain and directivity. Being an attractive solution creates the need to design such devices for various application scenarios. We have addressed that need by designing, simulating, and testing a rectangular microstrip patch directional antenna at 5GHz. Antenna patch and ground plane were designed with the well-known guided wavelength equation. The antenna performance, in terms of return loss at -10dB, gain, bandwidth, and the radiation pattern was analyzed with a simulation model. The proposed antenna achieved an impedance bandwidth of 77.8MHz (from 4.9662GHz to 5.0440GHz) and a gain of 6.26dBi at 5GHz. The antenna performance was verified with a software defined radio platform. We found that the software radio measurements confirmed the key simulation results. Furthermore, the extensive use of simulation enabled us to develop both antenna and digital baseband algorithms in parallel.