A reconfigurable antenna with omnidirectional and directional patterns for MIMO systems

In this paper, we propose a novel pattern reconfigurable planar antenna for employment in a 2×2 multiple input, multiple output (MIMO) system. By switching between the microstrip elements, the antenna can generate a single omnidirectional mode or four directional modes. The design has been tuned for a frequency of 3.8 GHz and has a bandwidth of at least 400 MHz, depending on the configuration. The flexibility in directional and omnidirectional operation, in concert with the wide operating bandwidth, makes this antenna an ideal candidate for future MIMO systems. This paper presents the antenna array architecture as well as simulated return loss and mutual coupling.