High gamma electronic tuner
View Patent ↗An RF electronic impedance tuner uses multiple PIN diodes, Varactors or MOSFETs, mounted in a low loss slab-line, between the bottom surface of the center conductor and ground, are DC controlled individually and spaced appropriately along the slab-line in order to generate maximum Gamma and bandwidth. The electronic tuner is combined with a slide screw tuner, using the same slab-line in various configurations, before, after or sharing the same slab-line section, mounted on top of each-other. Calibration on a VNA allows high Gamma and harmonic tuning.
1. Impedance tuner comprising a slotted airline (slab-line) with an input (test) port and an output (idle) port, a center conductor between the ports, and grounded vertical metallic walls;
and a multitude of remotely controlled electronic RF switches mounted on the center conductor of the slab-line,
whereby the switches are connected between the bottom of the center conductor and RF ground, and are appropriately spaced along the slab-line and are individually controlled by a tuner controller,
whereby the controller comprises an electronic control board, a switch control matrix and control software.
2. The tuner as claim 1 , whereby the switches are PIN diodes.
3. The tuner as in claim 1 , whereby the switches are MOSFET transistors.
4. The tuner as in claim 3 , whereby the transistor's drain terminal is connected to the center conductor, the source terminal is connected to ground and the gate terminal is connected to control.
5. The tuner as in claim 1 , whereby the switches are variable capacitors (Varactors).
6. The tuner as in claim 1 , whereby the switches are placed along the center conductor of the slab-line at individual distances to each other, said distances being selected in order for the tuned points to approach maximum coverage of reflection factors over the Smith chart and over a wide frequency range, when the switches are toggled between ON and OFF in a multitude of permutations.
7. Impedance tuner comprising
a) a slotted airline (slab-line) having an input (test) port and an output (idle) port, a center conductor between the ports and two grounded metallic walls,
b) an electro-mechanical tuner and c) an electronic tuner,
whereby
the electro-mechanical tuner comprises at least one adjustable reflective probe (slug) capacitively coupled with the center conductor and being insertable into the slot of the slab-line, approaching the center conductor from the top and movable parallel to the axis of the slab-line;
and whereby
the electronic tuner comprises a multitude of remotely controlled electronic switches, connected between the bottom of the center conductor and RF ground,
said reflective probe and electronic switches sharing sections of the center conductor, the reflective probe approaching from the top and the electronic switches attached to the bottom of the center conductor respectively.
8. The tuner as in claim 7 , whereby the reflective probe's horizontal and vertical positions are remotely controlled by a tuner controller using stepper motors and appropriate control gear and software.
9. The tuner as in claim 7 , whereby the reflective probe is manually controlled using micrometric screws and gear.