A reconfigurable printed monopole antenna for MIMO application

The new reconfigurable antenna array is demonstrated for multiple input multiple output (MIMO) communication systems. The antenna system consists of an array of two printed monopole antenna separated by a distance of 10.2 mm (of the lowest frequency band). Each of the dipoles can be reconfigured in length using PIN diode switches. This has been done by changing the switch state to either on or off mode. With the switch closed, the antenna operated at a lower frequency of 2.3 GHz, and to switch opened, the antenna operated at 3.5 GHz. The preference of reconfigurable antenna is that, the radiation characteristics are certain, since the resonance frequency is changed. Invasive Weed optimization(IWO) algorithm is used for the design and optimization of the single printed monopole antenna, to operate at these frequencies. This algorithm is then applied to design two channel MIMO antenna arrays for high degree of isolation. It is shown that good MIMO performance can be achieved even for small element spacing. The simulation results are presented.