Efficiency-Based Approach to Quantifying “Tuneability" Performance in Frequency-Agile Narrowband Antennas

Many communications systems require reconfigurable band access in compact form factors. Contemporary literature routinely reports `tuneability' (or frequency agility) in input response terms (S11), yet repeatable efficiency data were reported in <;40% of cases surveyed. Despite the low efficiencies associated with many tuneable narrowband antennas, e.g. electrically small antennas (ESAs), referenc...