Fast Switched-Stub Impedance Tuner Reconfiguration for Frequency and Beam Agile Radar and Electronic Warfare Applications

Tunable matching networks using switched stubs show promise for real-time impedance matching in high-power radar and jamming applications based on the emerging developments of high-power switches. These self-tuning transmitter amplifiers will quickly maximize range upon changing operating frequency in a dynamically changing spectrum environment. In this paper, we present a fast tuning algorithm capable of maximizing the output power from a tuner with six switched stubs. The control of the tuner from a software-defined radio platform is demonstrated, and complete optimization for output power can be performed in under
$35 \ \mu\mathrm{s}$
following a change in operating frequency or antenna impedance. The algorithm is expected to be applicable to emerging high-power switches with similar reconfiguration times.