Focus created, in 2000, the Programmable Harmonic Tuner (PHT) using Harmonic Rejection Resonators and in 2004 the wideband multi-carriage harmonic tuner concept (MPT), for which it holds several patents.
The PHT tuners are now discontinued but always supported.
Harmonic Tuners – MPT
- Two, three (or four) wideband probes, cascaded and independently movable inside the same slabline and
- Appropriate calibration and tuning routines
These tuners allow, among other, generating independent impedances at two, three (or four) harmonic frequencies, simultaneously and accurately. Impedances at other than harmonic frequencies F1, F2, can also be tuned, as long as they satisfy the relation F2 > 1.2*F1.
The most popular tuner types are
- the MPT (or MPT-Classic) with three probes (up to 3 frequencies) and
- the MPT-Lite with two probes (up to 2 frequencies).
- Protected by 6 US Patents