An efficient co-located MIMO antenna for compact terminals
The limited volume of mobile handset and the phenomenon of chassis excitation complicate the design of multiple antennas for MIMO applications. In this work, a compact co-located dual-antenna system implemented on one edge of a 100 mm by 40 mm chassis is proposed for operation below 1 GHz. The dual-antenna structure includes a folded monopole to excite the fundamental electric dipole mode of the chassis and a coupled loop working at its own fundamental magnetic dipole mode. In this way, angle and polarization diversities are achieved. In order to overcome the coupling induced by the close proximity between the feed lines of the two antennas, the phase of the feed current on the folded monopole can be optimized to achieve an isolation of above 20 dB. The phase optimization approach can also be applied to other multi-antenna systems that has similar coupling problem from the proximity of feeds. Moreover, to compensate for the narrowband property, the loop antenna can be made tunable to cover a large bandwidth. Good MIMO performance, in terms of capacity and multiplexing efficiency, is attained with the proposed antenna system. The co-located dual antenna prototype was fabricated and its performance was verified in measurements.
- Technology and Engineering
5th COST IC1004 Management Committee Meeting
- EIT_ANTCHN Antenna-Channel Harmonization for Throughput Enhancement in Advanced Mobile Terminals
- Radio Systems
- Electromagnetic theory