Antenna matching circuit optimization including stop band definitions

Antennas can be made more broadband, efficient and selective using external matching circuits. The matching circuits can be easily optimized for maximal performance. In the design of matching circuits using real components that include losses it is important to optimize the efficiency of the matching circuit, not the impedance match as such. The selectivity of the antenna can be increased by specifying stop band criteria. In the optimization there is a trade-off between the passband and stop band performance so that the target levels of these bands have to be selected carefully.