On the Conductive Loss of High- Frequency Reconfigurable Antennas for LTE Frequencies

Intrinsically narrowband and highly tunable systems are a promising way to address the bandwidth challenge of long-term evolution. However, narrowband antennas exhibit low efficiencies. This communication details the loss mechanism of narrowband antennas by investigating the contribution of the resistance of the tuner, the soldering tin, and the conductivity of the antenna material. It shows that conductive loss from the nonperfect electric conductor becomes the main source of loss for certain {Q} values. This loss is intrinsic to the antenna manufacturing and cannot be mitigated even with the best conductor, i.e., silver. Therefore, conductive loss poses a limit to narrowband antennas and to tuning range.