Synthetic load pull tuning probe and methods
View Patent ↗Multi-band remotely configurable synthetic tuning probes for slide screw impedance tuners allow combined larger frequency coverage beyond the capacity of existing tuning probes using the single horizontal and vertical axis mechanism of a prior art single probe, single band tuners. This is done by combining three tuning slugs, a center controlling slug and two dependent side slugs into a configurable synthetic tuning probe mounted in the single mobile tuner carriage and controlled using the same single vertical axis mechanism. The side slugs are spring-loaded towards and slide vertically independently on each other on both sides of the center slug and are lockable at distinct relative vertical positions. Their vertical position is controlled by the prongs of a fork permanently attached to the tuner slabline which hook on to the slide slugs separately.
1 . An automatically configurable synthetic tuning probe system for a load pull tuner, comprises:
the load pull tuner including a slabline with a center conductor linking two ports, a control port, and a neutral port, and at least one remotely controlled mobile carriage moving along the slabline and having a vertical axis mechanism which moves perpendicular to the slabline, wherein the vertical axis mechanism is configured to holds and being remotely controlled for the configuration of the synthetic tuning probe capacitively coupled with the center conductor;
the synthetic tuning probe including three parallelepiped tuning slugs with a front, a back and two side walls, wherein the three parallelepiped tuning slugs are formed by a center tuning slug confined between two side tuning slugs along the slabline, a first side slug towards the control port and a second side slug towards the neutral port, wherein the center tuning slug is positioned at the vertical axis and wherein the two side slugs slide on their side wall vertically against the side walls of the center slug and are lockable at distinct relative vertical positions using an interlock mechanism; and
the configuration of the synthetic tuning probe being remotely controlled and including:
studs protruding from the front and the back wall of each side of the two side slugs perpendicular to the slabline, and an unmovable horizontal fork being parallel to the slabline for controlling independently a vertical position of a side slug relative to the other slugs using only movement of the carriage and the vertical axis, and an automated procedure for controlling the vertical position of the two side slugs.
2 . The automatically configurable synthetic tuning probe system of claim 1 , wherein the unmovable horizontal fork being attached to the slabline close to the control port and having two horizontal prongs with a wide opening segment between the two prongs towards the control port and a narrow opening segment between the prongs towards the neutral port, wherein the narrow opening segment having the same width as the slugs and the wide opening segment having the same width as the slugs and the protrusion of the studs.
3 . The automatically configurable synthetic tuning probe system of claim 2 , wherein the automated procedure for configuring the synthetic tuning probe comprising the following steps of:
1) moving the carriage close to the control port;
2) controlling the vertical position of the side slugs configured:
2a) to control the vertical position of the first side slug, the carriage is moved close enough to the control port, for the first side slug to enter within reach of the narrow segment of the two prongs;
2b) to control the vertical position of the second side slug, the carriage is moved further closer to the control port, for the second side slug to enter within reach of the narrow segment of the prongs;
3) lowering or lifting the first side slug we engage the first side slug as in step 2a) and lower or lift the center slug until locked;
4) lowering or lifting the second side slug we engage the second side slug as in step 2b) and lower or lift the center slug until locked;
5) lowering or lifting the center slug relative to the side slugs, we engage both side slugs subsequently as in steps 2a) and 2b) and lower or lift the center slug until locked.
4 . The automatically configurable synthetic tuning probe system of claim 1 , wherein the interlock mechanism using sets of troughs centered vertically on the surface of the two side slugs facing the center slug and sets of spring-loaded steel balls protruding from either side wall of the center slug facing the two side slugs and aligned with the troughs, to allow, when lodged into the troughs, locking of the two side slugs against the center slug at distinct vertical positions.
5 . The automatically configurable synthetic tuning probe system of claim 1 , wherein the carriage and vertical axis of the load pull tuner are remotely controlled using stepper motors and gear.