A Microstrip Antenna Array for Indoor Wireless Dynamic Environments

A planar microstrip antenna array with a Butler matrix has been implemented to form a microstrip antenna array that has narrow beamwidth, circular polarization, and polarization diversity. This microstrip antenna array improves the system performance in indoor wireless dynamic environments. A circularly polarized microstrip antenna array is designed such that it consists of four identical linearly polarized patches. A 2 times 2 planar microstrip antenna array and a 4 times 4 Butler matrix have been designed and simulated using advanced design system and Matlab software. The measured results show that a combination of a planar microstrip antenna array and a 4 times 4 Butler matrix creates four beams; two of these beams have right-hand circular polarization and the other two have left-hand circular polarization.