Implementation of a Frequency-Agile MIMO Dielectric Resonator Antenna

The design and implementation of a two-port frequency-reconfigurable multiple-input multiple-output (MIMO) dielectric resonator antenna is described in detail. The frequency agility is achieved by the addition of reconfigurable parasitic slot loadings in proximity to the dielectric resonator block. Because of the orthogonality between the two radiating ports, the operating frequency of each port can be individually tuned without significantly affecting the frequency response of the other port. Hence, the proposed antenna can have two modes of operation: multifrequency mode and MIMO mode. In the multifrequency mode, the antenna ports can independently sweep through the frequency band of interest and look for nearby potential users. On the other hand, the antenna ports can be reconfigured into an MIMO antenna to boost up the capacity whenever heavy data traffic is required and the channel condition is appropriate. These capabilities make the antenna suitable for dynamic spectrum-access applications in cognitive radios.