Small printed log-periodic array, matched with an active non-foster network

The design of a small printed-log-periodic antenna, loaded with an active matching network, for multiband applications is presented. A well-known, low-cost and low-profile antenna is re-engineered for including an additional impedance bandwidth in the lower UHF-band. The design method includes the use of the recently introduced sensitivity parameter Sens in order to find a suitable location for a transistor-based non-Foster network, realized with a Negative Impedance Converter (NIC).