Automatic tuning of multicavity filters of microwave signals
View Patent ↗The system for the automatically tuning of multicavity filters of high frequency signals, by means of screws sticking out from the lid of the plate incorporating said cavities, comprises a robotized movement imparting subsystem SUB- 1 A, a measuring subsystem SUB- 2 M for the extraction of the transfer characteristic, a subsystem SUB- 3 C to compare said measured values to reference parameters, a subsystem SUB- 4 G for the generation of said reference parameters, and a subsystem SUB- 5 CO enslaved to said SUB- 4 G and SUB- 1.
1. A system to automatically tune multicavity filters of high frequency (HF) signals, comprising:
at least one filter body with a plate which includes said cavities and is crossed by metallic tuning screws having heads sticking out of said plate and stems penetrating into one of said cavities, said system including:
at least one arm for coupling and moving said tuning screws to adjust the resonant frequency of each corresponding cavity;
a subsystem (SUB- 1 A) of driving and robotized movement of said screws as well for the regulation of the entity of their penetration inside the cavity, consisting of at least one frictioning device (MF- 1 ) and at least one fine tuning regulation device (MRS- 2 );
a measuring subsystem (SUB- 2 MI) for the real time measurement of scatter parameters S 1 , S 2 . . . Si, . . . SN (N being the number of tuning screws), the measuring subsystem comprising a VNA (Vectorial Network Analyzer), adapted to measure the real-time frequency response of an under-test filter (DUT);
a subsystem SUB- 3 C for comparing the values S 1 , S 2 . . . Si, . . . SN measured by SUB- 2 MI with parameters of reference Sri generated by a reference parameter-generating subsystem SUB- 4 G;
and a subsystem (SUB- 5 ) comprising a controller (CONT) enslaved to SUB- 4 G for controlling the means included in SUB- 1 A and SUB- 5 , wherein the subsystem SUB- 3 C compares the real-time frequency response from SUB- 2 MI with a reference frequency response recorded in a non-volatile memory of SUB- 4 G and feeds the results of the comparison as MSE (Mean Square Errors) to the controller (CONT) of SUB- 5 .
2. The system according to claim 1 , in which the robotized subsystem (SUB- 1 A) includes two coaxial arms.
3. The system according to claim 1 , in which the subsystem SUB- 5 receives said MSE and controls the subsystems SUB- 1 A and SUB- 4 G.
4. The system according to claim 1 , in which the subsystem SUB- 4 G includes a reference parameter generator ( 6 ) and an algorithm generator ( 5 ).
5. The system according to claim 4 , in which said reference parameter generator ( 6 ) includes at least:
a measurement tool for measuring reference parameters Sr 1 , Sr 2 . . . Sr . . . SrN from a perfectly-tuned reference unit; and
a storage device for storing the measured reference parameters Sr 1 , Sr 2 . . . Sri . . . SrN.
6. The system according to claim 1 , wherein said at least one frictioning device is a screw driver.
7. The system according to claim 1 , wherein a single arm is used to couple and move all of said tuning screws.
8. A system to automatically tune multicavity filters of high frequency (HF) signals, comprising:
at least one filter body with a plate which includes said cavities and is crossed by metallic tuning screws having heads sticking out of said plate and stems penetrating into one of said cavities, said system including:
at least one arm for coupling and moving said tuning screws to adjust the resonant frequency of each corresponding cavity;
a subsystem (SUB- 1 A) of driving and robotized movement of said screws as well for the regulation of the entity of their penetration inside the cavity, consisting of at least one frictioning device (MF- 1 ) and at least one fine tuning regulation device (MRS- 2 );
a measuring subsystem (SUB- 2 MI) for the real time measurement of scatter parameters S 1 , S 2 . . . Si, . . . SN (N being the number of tuning screws);
a subsystem SUB- 3 C for comparing the values S 1 , S 2 . . . Si, . . . SN measured by SUB- 2 MI with parameters of reference Sri generated by a reference parameter-generating subsystem SUB- 4 G, the reference parameter-generating subsystem SUB- 4 G comprising a reference parameter generator ( 6 ) and an algorithm generator ( 5 ) comprising a processor for loading the scatter parameters S 1 , S 2 . . . Si . . . SN measured by SUB- 2 MI and determining a difference (δ ε ) between a current measurement of one of said scatter parameters (ε 1 ) and a prior measurement of one of said scatter parameters (ε 0 ) while a corresponding tuning screw is being inserted, wherein when δ ε is less than 0 the tuning screw is inserted and when δ ε is less than a threshold (lim ε), insertion of the corresponding tuning screw is stopped;
and a subsystem (SUB- 5 ) comprising a controller (CONT) enslaved to SUB- 4 G for controlling the means included in SUB- 1 A and SUB- 5 .