Antenna analyzer is a device used for measuring the input impedance of antenna systems in radio electronics applications. In radio communications systems, including amateur radio, an antenna analyzer is a common tool used for troubleshooting antennas and feedlines as well as fine tuning their performance. 

Antenna bridges have long been used in the broadcast industry to tune antennas. A bridge is available which measures complex impedance while the transmitter is operating, practically a necessity when tuning multi tower antenna systems. In more recent times the direct reading network analyzers have become more common.