A novel compact antenna for broadband MIMO

In this paper, a simple broadband antenna in a compact size is firstly proposed. Antenna configuration and its characteristics such as VSWR, radiation patterns, and gain have been explored and discussed. The measured results illustrate that the proposed antenna offers a bandwidth of over 50% for VSWR less than 2. It also has high cross-polarization levels, and good gains-varying from about 0.5 dBi to 4.5 dBi in the whole entire bandwidth. Moreover, we introduced some similar broadband antennas which also offer relative bandwidth of over 50% at different centre frequencies. These antennas can be easily obtained by adjusting some simple geometrical parameters without changing material or substrate´s thickness. Secondly, we propose a simple and compact two-port broadband array which is based on the elemental design. The mutual coupling of ports of the array is kept around -10 dB at the low frequence band and around -20 dB at the high frequence area of the array´s bandwidth. The proposed broadband antennas are promissing for wideband applications such as broadband MIMO systems.