Tomohisa Kohiyama

Variable beamwidth shorted patch antenna array for indoor positioning

Variable beamwidth antennas can optimize the radio coverage of a transmitter for indoor positioning. In this study, we developed a small variable beamwidth antenna array suitable for indoor positioning that is comprised of electrically small shorted patch antennas and is adapted for use with the indoor messaging system (IMES). We did theoretical calculations and experimental measurements to examine the antenna properties. Our results showed that beamwidth variations from 40° to 65° can be obtained and that the boresight gain is adequate for use with IMES transmitters.

Electrically small shorted patch antenna array with switchable radiation patterns for indoor messaging system

A planar antenna array with switchable radiation patterns is presented for an indoor messaging system (IMES) transmitter. The antenna array comprises four electrically small shorted patch antennas, and can switch the radiation patterns between vertical and horizontal modes. The antenna properties were examined by performing theoretical calculations and experiments. A fabricated antenna array on a printed circuit board is as small as 124 mm by 124 mm, and the measurements demonstrate that two radiation patterns of vertical and horizontal modes are obtainable. We believe that the antenna array should improve the usability of the IMES transmitter.