Compact harmonic amplitude and phase controller

1. A harmonic RF attenuation and transmission phase controller (HAPC) having an input and an output port and transmission media between the ports;

whereby the transmission media comprises a cascade of slotted airline (slabline), at least two adjustable signal couplers (wave-probes) having a coupled port and an isolated port, multi-port signal combiner having at least two input ports and one combination port, flexible RF cables and characteristic impedance (Zo) terminations;

and whereby the slabline comprises two parallel conductive walls, a center conductor and one input and one idle port and has characteristic impedance Zo;

and whereby the wave-probes are inserted diametric from opposite sides into the slabline;

and whereby the signal traversing the slabline is coupled into each of the wave-probes;

and whereby the signal coupled into each wave-probe is injected into an associated input port of the signal combiner and the combined signal exits from the combination port into the output port of the HAPC,

and whereby the coupling factor of the wave-probes controls the amplitude and whereby the physical distance of the wave-probes from the input port controls the phase of the transmission factor of the HAPC at the fundamental and harmonic frequencies,

and whereby the total length of the slabline available for wave-probe horizontal movement is at least one wavelength at the lowest frequency of operation.

2. The HAPC of claim 1 , whereby each branch of the transmission media comprises one amplifier inserted between the coupled port of the wave-probe and the input port of the signal combiner.

3. The HAPC of claim 1 whereby the transmission media comprises one amplifier inserted between the combination port of the signal combiner and the output port.

4. The HAPC as in claim 1 , whereby

one port of the slabline is the input port, and whereby

the idle port of the slabline, and

the isolated ports of the wave-probes

are terminated with characteristic impedance (Zo).

5. The HAPC as in claim 4 , comprising at least two mobile carriages, having vertical axis each, the carriages being mounted diametric on top and bottom of the slabline and sliding independently horizontally along the slabline.

6. The HAPC as in claim 5 , whereby the wave-probes are attached to the vertical axis of the carriages and can be inserted independently diametric from opposite directions into the slot of the slabline and positioned at various distances from the center conductor.

7. The HAPC as in claim 6 , whereby the vertical axes are remotely controlled allowing independent adjustment of the coupling factors between the center conductor of the slabline and the wave-probes.

8. The HAPC as in claim 7 , whereby the carriages are remotely controlled.

9. The HAPC as in claim 4 , whereby the coupled ports of the wave-probes are connected to the input ports of the signal combiner using flexible RF cables and whereby the output port of the signal combiner is connected to the output port of the HAPC and whereby the isolated ports of the couplers are terminated with characteristic impedance (Zo).

10. The HAPC as in claim 4 or 9 , whereby Zo is 50 Ohms.

11. A calibration method for HAPC as in claim 10 , wherein the HAPC is connected to a pre-calibrated vector network analyzer (VNA) using RF cables and to a control computer using digital cables;

and scattering (s-) parameters are measured by the VNA between the input port and the output port of the HAPC at the fundamental frequency (Fo) and at least one harmonic frequency (N*Fo), for various settings of the coupling factors and the distances between the wave-probes and the input port, the settings being controlled by the computer, which is in operative communication with the VNA, whereby N=2, 3 . . . , in following steps:

a) all wave-probes are initialized (withdrawn from the slabline, reducing the coupling factors to negligible value) and s-parameters of the HAPC are measured and saved in a matrix [S00];

b) wave-probe 1 is inserted into the slabline in a number of steps Y1.j and for each Y1.j it is moved horizontally in a number of steps X1.i;

c) s-parameters [S1(X1.i,Y1.j)] are measured between the input and output ports and saved;

d) wave-probe 1 is initialized and step b) is applied to wave-probe 2 resulting in a matrix [S2(X2.i,Y2.j)];

e) step d) is applied to all other wave-probes, whereby all wave-probes are initialized except the wave-probe being controlled;

f) s-parameters of all wave-probes at all horizontal and vertical settings, except the wave-probe whose horizontal position is closest to the input port, are de-embedded using matrix [S00] −1 ;

g) permutations of all s-parameter matrices are created in computer memory and saved in calibration files for all selected frequencies for later use.

12. A tuning method for HAPC uses calibration data generated in claim 11 as follows:

a) s-parameters are loaded in memory for selected frequencies Fo, 2Fo, . . . NFo;

b) error function EF is generated comprising the sum of vector differences between target transmission factor S21.T(F) and calibrated transmission factor S21.C(F) for all selected frequencies F=Fo, 2Fo, . . . NFo;

c) a search algorithm through the s-parameter space selects the carriage positions X1, X2, . . . XN and vertical axis positions Y1, Y2, . . . YN corresponding to minimum error function EF in step b);

d) carriages and vertical axes are positioned as in step c).

13. Interpolated transmission factors S21(F).I at each frequency (F) are used in claim 12 , instead of calibrated ones.