Mobile Phased Antenna Array @ 6 GHz with Digitally Tunable Capacitor Phase Shifters

This paper evaluates the performance of the digitally tunable capacitor phase shifter, mounted on a phased antenna array, in the frequency range from 5 to 6 GHz. It is based on the WS1042, a single-chip, fully-integrated tunable RF capacitor featuring four high resolution, tunable MEMS capacitors under control of a MIPI RFFE serial interface. The design of the phased antenna array consists of four quarter wavelength dipoles printed on the short edge of an FR4 substrate. Simulations including 70° and 105° phase shift demonstrated that the array can steer a beam wider than 80° and 100° respectively with a maximum gain of 7 dBi. The measurements, carried out in the MVG SG24, confirm that the prototype allows to reach the same scan angle observed in the simulations, but highlight a significant decrease in gain of 5 dB, due to the loss introduced by the four phase shifters and the port divider.