Effect of antenna Q to the radiation efficiency of tunable antennas

Narrowband tunable antennas have gained interest as an alternative to wideband antennas in mobile applications. However, one of the key problems of tunable antenna systems are the increased losses and thus the reduced efficiency of the antenna systems. We will show using example antennas how the antenna Q (quality factor) and the component losses together determine the efficiency of the antenna system. Overall, narrowband antennas are much more sensitive to losses in the matching and tuning elements and thus low-loss tuning components should be used to get good performance.