JP5120278B2 - Superconducting tunable filter device, nonlinear strain measuring device, nonlinear strain measuring method - Google Patents

Description

  The present invention relates to a superconducting tunable filter device, a nonlinear distortion measuring device, and a nonlinear distortion measuring method.

In recent years, with the shift to high-speed and large-capacity data communication such as next-generation mobile communication systems and broadband wireless access, effective use of frequencies has become indispensable.
In particular, in the transmission system of a radio base station, leakage power to adjacent channels is severely limited by the Radio Law. For this reason, there is an increasing demand for communication devices with small nonlinear distortion.
By the way, it is conceivable to use a so-called 2-tone method as a method for measuring nonlinear distortion of a sample (measurement object) such as a high-frequency device or a high-frequency component.

For example, as shown in FIG. 10, two fundamental wave signals having different frequencies f ₁ and f ₂ are input to the sample at equal levels. Intermodulation distortion (IMD) signals with frequencies 2f ₁ -f ₂ and 2f ₂ -f ₁ are generated on both sides of the fundamental wave signals with frequencies f ₁ and f ₂ due to the nonlinearity of the samples. These IMD signals are measured using a spectrum analyzer. Thereby, the nonlinear distortion of the sample is measured.

In this case, a fundamental wave signal having a level much higher than that of the IMD signal is input to the spectrum analyzer. Therefore, a normal attenuator (attenuator) having almost no frequency dependence is provided.
However, when an attenuator is provided, the IMD signal is attenuated together with the fundamental wave signal. In some cases, the IMD signal becomes a noise level of the spectrum analyzer, and it is difficult to measure the IMD signal with high accuracy. In particular, it is difficult to measure a slight distortion component such as passive intermodulation distortion (PIM) with high accuracy.

Therefore, it is conceivable to suppress the fundamental wave signal by providing a cancel circuit, branching the fundamental wave signal, adjusting the phase and amplitude of the branched signal, and synthesizing it with the fundamental wave signal.
When using a superconducting filter, in order to compensate for the intermodulation distortion generated in the superconducting filter, a distortion signal having a reverse characteristic of the intermodulation distortion expected to be generated in the superconducting filter is output from the superconducting filter. There is also a distortion compensation circuit that is combined with a signal to be synthesized.

JP 2004-032584 A

Furuno et al., “High-Tc Superconducting Microwave Device High Dynamic Range Nonlinear Strain Amplitude / Phase Measurement”, IEICE, IEICE Technical Report, SCE 2007-6, MW 2007-6 (2007-04), No. 1 27th to 30th pages

However, in the case where the cancellation circuit is provided to suppress the fundamental wave signal, the circuit for suppressing the fundamental wave signal is complicated, and phase adjustment is particularly difficult. For this reason, it is difficult to measure nonlinear distortion with high accuracy.
Moreover, the communication equipment is composed of parts having different nonlinear distortion levels such as semiconductor power amplifiers and cables. For this reason, it is essential to be able to measure distortion components with high accuracy and high dynamics in order to further reduce distortion and to separate distortion factors.

Further, in order to obtain optimum communication access, a plurality of systems, that is, communication devices corresponding to a plurality of frequency bands are desired. For this reason, it is also important to be able to measure distortion components with high accuracy in a wide frequency range.
Therefore, it is desirable to measure nonlinear distortion with high accuracy and high dynamicity in a wide frequency range with a simple configuration.

For this reason, this superconducting tunable filter device is formed of a dielectric substrate, a resonator pattern and input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a superconducting material on the back surface of the dielectric substrate. A band rejection superconducting filter comprising a ground layer having an opening for forming a filter characteristic having two reject bands, and a rod for tuning the reject bandwidth of the filter characteristic of the superconducting filter And a rod position adjusting means for adjusting the position of the rod with respect to the superconducting filter so that the size of the opening is adjusted .

The nonlinear distortion measuring apparatus is a nonlinear distortion measuring apparatus that inputs two basic signals of different frequencies to a sample and measures an intermodulation distortion signal generated by the nonlinearity of the sample, the basic signal output from the sample and the sample A superconducting tunable filter device that attenuates only the fundamental signal among the intermodulation distortion signals caused by the nonlinearity of the substrate is formed by a superconducting material on the surface of the dielectric substrate and the dielectric substrate. Band-rejection type comprising: a resonator pattern and an input / output feeder, and a ground layer formed of a superconducting material on the back surface of the dielectric substrate and having an opening for forming a filter characteristic having two reject bands Tuning of the superconducting filter, the reject band width of the filter characteristic of the superconducting filter A rod for it may be a requirement that comprises a rod for position adjustment means for the size of the opening to adjust the position of the rod relative to the superconducting filter as adjusted.

In this nonlinear distortion measurement method, two basic signals of different frequencies are input to a sample, a dielectric substrate, a resonator pattern and input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a dielectric substrate A band-rejection type superconducting filter comprising a ground layer having an opening for forming a filter characteristic having two reject bands, and rejecting the filter characteristic of the superconducting filter. A superconducting tunable filter device comprising a rod for tuning the bandwidth and a rod position adjusting means for adjusting the position of the rod relative to the superconducting filter so that the size of the opening is adjusted. Among the fundamental signal output from the signal and the intermodulation distortion signal caused by the nonlinearity of the sample Only to attenuate the issue, a nonlinear distortion measuring method for measuring the intermodulation distortion signal, and sets the frequency of the two basic signal according to the sample, depending on the frequencies of the two basic signal, superconducting tunable It is a requirement to adjust the center frequency and reject bandwidth of the filter characteristics of the filter device.

  Therefore, according to the present superconducting tunable filter device, non-linear strain measuring device, and non-linear strain measuring method, there is an advantage that non-linear strain can be measured with high accuracy and high dynamic in a wide frequency range with a simple configuration.

It is a schematic diagram which shows the structure of the superconductive tunable filter apparatus concerning this embodiment. It is a typical perspective view which shows the structure of the superconducting filter with which the superconducting tunable filter apparatus concerning this embodiment is equipped, and a plate. (A) is a schematic surface view showing a configuration of a superconducting filter provided in the superconducting tunable filter device according to the present embodiment, and (B) is provided in the superconducting tunable filter device according to the present embodiment. It is a typical back view which shows the structure of a superconductive filter. It is a figure which shows the characteristic of the superconducting filter with which the superconducting tunable filter apparatus concerning this embodiment is equipped. It is a schematic diagram which shows the structure of the superconductive tunable filter apparatus concerning this embodiment. It is a mimetic diagram showing composition of a nonlinear distortion measuring device provided with a superconductivity tunable filter device concerning this embodiment. (A) is a typical surface view showing a configuration of a modification of the superconducting filter provided in the superconducting tunable filter device according to the present embodiment, and (B) is a superconducting tunable filter device according to the present embodiment. It is a typical back view which shows the structure of the modification of the superconducting filter with which it is equipped. (A) is a schematic surface view showing a configuration of another modification of the superconducting filter provided in the superconducting tunable filter device according to the present embodiment, and (B) is a superconducting tunable according to the present embodiment. It is a typical back view which shows the structure of the other modification of the superconducting filter with which a filter apparatus is equipped. It is a typical perspective view which shows the structure of the modification of the superconducting tunable filter apparatus concerning this embodiment. It is a schematic diagram which shows the structure of the conventional nonlinear distortion measuring apparatus.

Hereinafter, a superconducting tunable filter device, a nonlinear distortion measuring device, and a nonlinear distortion measuring method according to the present embodiment will be described with reference to FIGS.
The nonlinear distortion measuring apparatus according to the present embodiment is a nonlinear distortion measuring apparatus including a superconducting tunable filter device as an elemental technology for advanced shared use of radio waves in a mobile communication system, for example.

As shown in FIG. 6, the present nonlinear distortion measuring apparatus inputs two basic signals having different frequencies f ₁ and f ₂ to a sample 50, and generates an intermodulation distortion signal (IMD signal; PIM) generated by the nonlinearity of the sample 50. Signal; frequency 2f ₁ −f ₂ , 2f ₂ −f ₁ ). The sample 50 is an object to be measured such as a high frequency device or a high frequency component.
This nonlinear distortion measuring apparatus includes a superconducting tunable filter apparatus 1 that attenuates only the fundamental signal among the fundamental signal output from the sample 50 and the intermodulation distortion signal generated by the nonlinearity of the sample. That is, this nonlinear distortion measuring apparatus includes the superconducting tunable filter apparatus 1 instead of the attenuator used in the conventional nonlinear distortion measuring apparatus.

For this reason, in the nonlinear distortion measurement method of this embodiment, two basic signals having different frequencies are input to the sample 50, and only the basic signal out of the basic signal and the intermodulation distortion signal output from the sample 50 is a superconducting tunable. The signal is attenuated by the filter device 1 and the intermodulation distortion signal is measured.
In particular, in the present embodiment, the frequencies of two basic signals output from the first signal source 2 and the second signal source 3 are set according to the sample 50, and the superconducting tuner is set according to the frequencies of the two basic signals. The bull filter device 1 can be tuned.

Here, tuning is performed by adjusting the center frequency and reject bandwidth of the filter characteristics of the superconducting tunable filter device 1.
Here, the center frequency of the filter characteristic of the superconducting tunable filter device 1 is a frequency at an intermediate position between the two reject bands of the filter characteristic. That is, the center frequency of the filter characteristic is an average frequency of the peaks of the two reject bands. Further, the reject bandwidth of the filter characteristic of the superconducting tunable filter device 1 is an interval between two reject bands (distance between peaks). That is, the reject bandwidth of the filter characteristic is the frequency difference between the peaks of the two reject bands.

  Note that the peak frequencies of the two reject bands of the filter characteristics are preferably matched to the frequencies of the two basic signals. In this case, the center frequency of the filter characteristic is the same as the frequency at the intermediate position between the two basic signals (the average frequency of the two basic signals). The reject bandwidth of the filter characteristic is the same as the interval between two basic signals (frequency difference between the two basic signals).

  Specifically, as shown in FIG. 6, the nonlinear distortion measuring apparatus includes a first signal source 2, a second signal source 3, a first power amplifier 4, a second power amplifier 5, a first isolator 6, and a second isolator 6. An isolator 7, a 3 dB coupler (coupler) 8, a third isolator 9, a superconducting tunable filter device 1, and a spectrum analyzer 10 are provided. A sample 50 is placed between the third isolator 9 and the superconducting tunable filter device 1.

Here, the first signal source 2 is a signal source for outputting a basic signal of frequency f _1.
The second signal source 3 is a signal source for outputting a basic signal of the frequency f _2.
The first power amplifier 4 is connected to the first signal source 2 and is a power amplifier that amplifies the basic signal having the frequency f ₁ .
The second power amplifier 5 is connected to the second signal source 3, a power amplifier for amplifying the fundamental signal frequency f _2.

The first isolator 6 is provided between the first power amplifier 4 and the 3 dB coupler 8.
The second isolator 7 is provided between the second power amplifier 5 and the 3 dB coupler 8.
The third isolator 9 is provided after the 3 dB coupler 8, that is, between the 3 dB coupler 8 and the sample 50.

The superconducting tunable filter device 1 is provided before the spectrum analyzer 10, that is, between the sample 50 and the spectrum analyzer 10.
Since this nonlinear distortion measuring apparatus is configured as described above, two basic signals of different frequencies f ₁ and f ₂ output from the first signal source 2 and the second signal source 3 are the first power amplifier. 4 and the second power amplifier 5, respectively, combined by a 3dB coupler 8, and input to the sample 50 at an equal level.

In this way, when two basic signals having different frequencies f ₁ and f ₂ are input to the sample 50, the sample 50 has intermodulation distortion at frequencies 2f ₁ −f ₂ and 2f ₂ −f ₁ due to its nonlinearity. Generate a signal. For this reason, two basic signals having different frequencies f ₁ and f ₂ and two intermodulation distortion signals (frequency 2f ₁ -f ₂ and 2f ₂ -f ₁ ) generated on both sides of the basic signal are obtained from the sample 50. Is output.

Of the two basic signals output from the sample 50 and the two intermodulation distortion signals, only two basic signals are attenuated by the superconducting tunable filter device 1.
Then, two intermodulation distortion signals are measured using the spectrum analyzer 10. Thereby, the nonlinear distortion of the sample 50 is measured.
The superconducting tunable filter device according to this embodiment will be described below with reference to FIG.

The superconducting tunable filter device includes a band rejection superconducting filter 11 and a tunable structure 12, as shown in FIG.
Here, as the tunable structure 12, a rod 13 and a plate 14 for tuning the superconducting filter 11, a position for adjusting the position of the rod 13 with respect to the superconducting filter 11 and the position of the plate 14 with respect to the superconducting filter 11. And adjusting means 15.

Here, the superconducting filter 11 is a band rejection type (notch type) filter that can sharply attenuate only two basic signals (fundamental wave signals).
In the present embodiment, as shown in FIGS. 1 to 3, the superconducting filter 11 includes a dielectric substrate 16, a resonator pattern 17 formed of a superconducting material on the surface of the dielectric substrate 16, and an input / output feeder 18. And a ground layer 19 formed of a superconducting material on the back surface of the dielectric substrate 16 and having an opening (slot) 19A. The superconducting filter 11 is also referred to as a filter substrate or a disk resonator.

Here, an MgO substrate is used as the dielectric substrate 16.
The dielectric substrate 16 is not limited to an MgO substrate (MgO single crystal substrate), and for example, a LaAlO ₃ substrate, a sapphire substrate, or the like may be used.
The resonator pattern 17, the input / output feeder 18 and the ground layer 19 are formed of a thin film (YBCO thin film) using a YBCO (Y-Ba-Cu-O) based superconducting material.

Here, the input / output feeder 18 is an input / output conducting wire for inputting / outputting a signal, and is composed of two orthogonal linear conducting wires as shown in FIG. One conducting wire extends to one end face (input end face) of the dielectric substrate 16, and the other conducting wire extends to another end face (output end face) orthogonal to one end face of the dielectric substrate 16.
Further, a disk pattern (disk structure; two-dimensional circuit pattern) is employed as the resonator pattern 17 in order to obtain good power durability and to minimize the distortion component from the superconducting filter itself. The disk pattern 17 is provided at a position where signals guided by the input / output feeder 18 are combined. However, the disk pattern 17 is formed so as not to contact the input / output feeder 18. The superconducting filter 11 having a disk pattern as the resonator pattern 17 is referred to as a disk type filter (planar circuit type filter).

When the disk pattern 17 is used, the center frequency of the filter characteristic of the superconducting filter 11 is determined by the diameter of the disk pattern 17. That is, by adjusting the diameter of the disk pattern 17, the center frequency of the filter characteristic of the superconducting filter 11 can be arbitrarily set.
Further, as shown in FIG. 3B, by providing an opening 19A in the ground layer 19, a reject filter (notch filter) having two reject bands (notches) is constituted by one disk resonator. (See FIG. 4). That is, the opening 19A formed in the ground layer 19 is an opening for forming a filter characteristic having two reject bands. Here, the opening 19 </ b> A of the ground layer 19 is located at a position of 45 degrees with respect to the two conductors constituting the input / output feeder 18 and a position corresponding to a position far from the input / output feeder 18 on the outer periphery of the disk pattern 17. It is preferable to provide in.

Then, the filter characteristics for attenuating only the fundamental signal of the fundamental signal and the intermodulation distortion signal output from the sample 50 are obtained by making the position of each reject band correspond to the frequencies f ₁ and f ₂ of the fundamental signal. be able to.
In this case, the reject bandwidth of the filter characteristic of the superconducting filter 11 is determined by the size of the opening 19A provided in the ground layer 19 (here, since it is a circular slot, the diameter).

For example, the rejection bandwidth can be increased by increasing the size of the opening 19A provided in the ground layer 19. On the other hand, the rejection bandwidth can be narrowed by reducing the size of the opening 19A provided in the ground layer 19.
Further, for example, by disposing the opening 19 </ b> A provided in the ground layer 19 inside the position corresponding to the outer periphery of the disk pattern 17, the reject bandwidth can be widened. On the other hand, by setting the opening 19A provided in the ground layer 19 outside the position corresponding to the outer periphery of the disk pattern 17, the reject bandwidth can be narrowed.

However, the center of the opening 19 </ b> A provided in the ground layer 19 is not overlapped with the center of the disk pattern 17. This is to prevent the resonance band, that is, the rejection band in the disk pattern 17 from becoming one. The size of the opening 19A provided in the ground layer 19 (here, the diameter is a circular slot) is preferably within λ / 4. This is because excessive resonance occurs. Note that λ _g is an intermediate wavelength between the two basic signals.

In particular, as described above, the conductor pattern portions such as the disk pattern 17, the input / output feeder 18, and the ground layer 19 are formed of the superconductor material as described above, thereby providing a very low loss and a steep reject band. The filter frequency characteristic is obtained.
For example, the frequency _f 1 of the two basic signal, if _{f 2} is in the vicinity of 5 GHz, the center frequency of the filter characteristic of the superconducting filter 11 is in the vicinity of 5 GHz, and the bandwidth and other includes the frequency _{f 1} of the first fundamental signal to resonate at two bands in a band including a fundamental signal of a frequency f _2, the disc pattern diameter, and may be set the size of the opening 19A provided on the ground layer 19.

Specifically, when the MgO substrate is used, if the diameter of the disk pattern 17 is about 11.1 mm and the diameter of the circular slot 19A of the ground layer 19 is 1 mm, 5 GHz of the signal input to the input / output feeder 18 Only basic signals of the frequencies f ₁ and f _{2 in} the vicinity are accumulated in the disk pattern 17. In other words, the signals f ₁ and f _{2 of} the basic signal coincide with the resonance frequency of the disk pattern 17 and are resonated and rejected by the disk pattern 17, while signals having frequencies outside the two bands (particularly intermodulation distortion signals). Is output as it is without resonating.

As a result, an attenuation of about 40 dB is obtained in the basic signal, and an excellent filter frequency characteristic (filter pass characteristic) having almost no loss outside the band including the frequencies f ₁ and f ₂ of the basic signal is obtained (see FIG. 4). ). For this reason, when the output signal from the sample 50 passes through the superconducting filter 11, the basic signal is attenuated by about 40 dB, but the intermodulation distortion signal is hardly attenuated (see FIG. 6). Therefore, it is possible to measure nonlinear distortion with high accuracy without the intermodulation distortion signal being buried in the noise level. That is, conventionally, measurement of nonlinear distortion has been possible only when the difference in signal level (signal amplitude difference) between the basic signal output from the sample 50 and the intermodulation distortion signal is about 80 dB. On the other hand, by using the superconducting filter 11, nonlinear distortion can be measured even when the difference between these signal levels is 120 dB or more. Therefore, nonlinear distortion can be measured with high performance and a wide dynamic range.

In this case, a YBCO superconducting material is used as the superconducting material, but the present invention is not limited to this.
For example, RBCO (R—Ba—Cu—O) based superconducting material, that is, RBCO based superconducting material using Nd, Sm, Gd, Dy, Ho instead of Y (yttrium) as R element (high temperature superconducting material). Conductive material) may be used. Also, BSCCO (Bi-Sr-Ca-Cu-O) -based superconductive material, PBSCCO (Pb-Bi-Sr-Ca-Cu-O) -based superconductive material, CBCCO (Cu-Bap-Caq-Cur-Ox, 1.5 <p <2.5, 2.5 <q <3.5, 3.5 <r <4.5) Other oxide superconducting materials such as superconducting materials (high temperature superconducting materials) It may be used. Further, a superconducting material (high temperature superconductor material) such as Nb or NbN compound may be used.

The rod 13 is a tuning rod for tuning the reject bandwidth of the filter characteristic of the superconducting filter 11.
Further, the plate 14 is a tuning plate for tuning the center frequency of the filter characteristic of the superconducting filter 11. The shape of the plate 14 is preferably circular.

Here, the rod 13 and the plate 14 are made of sapphire.
The material of the rod 13 and the plate 14 is not limited to this. For example, a dielectric material such as MgO, LaAlO ₃ , NdGaO ₃ , LSAT, LaSrGaO ₄ , LaGaO ₃ , YSZ, or TiO ₂ may be used. Further, for example, a magnetic material such as YIG may be used.

Further, as shown in FIGS. 1 and 5, the position adjusting means (position control means) 15 individually adjusts (controls) the position of the rod 13 and the position of the plate 14. For this reason, in this embodiment, the position adjusting means 15 includes a rod position adjusting means 15A and a plate position adjusting means 15B.
Here, the rod position adjusting means 15A includes a rod adjustment trimmer 20 (a fine adjustment variable element) connected to the rod 13 and a rod control means 21 for controlling the rod adjustment trimmer 20 (for example, linear introduction mechanism control). Mechanism).

The rod position adjusting means 15A adjusts the position of the rod 13 by controlling the rod adjusting trimmer 20 by the rod control means 21.
Here, the rod position adjusting means 15A adjusts the position of the rod 13 so that the size of the opening 19A provided in the ground layer 19 is adjusted. That is, the rod position adjusting means 15A adjusts the position of the rod 13 with respect to the opening 19A provided in the ground layer 19 of the superconducting filter 11. The rod control means 21 includes a driver circuit and a control circuit.

The plate position adjusting means 15 </ b> B includes a plate adjustment trimmer 22 connected to the plate 14 and a plate control means 23 for controlling the plate adjustment trimmer 22.
The plate position adjusting means 15B adjusts the position of the plate 14 by controlling the plate adjusting trimmer 22 by the plate control means 23.

  Here, the plate position adjusting means 15B adjusts the position of the plate 14 so that the distance between the plate 14 and the resonator pattern 17 is adjusted. That is, the plate position adjusting means 15B adjusts the position of the plate 14 with respect to the resonator pattern 17 of the superconducting filter 11. The plate control means 23 includes a driver circuit and a control circuit.

  Specifically, the above-described superconducting filter 11, rod 13 and plate 14 are accommodated in a package 24 as shown in FIG. And this package 24 is mounted on the cooling stage 26 in the vacuum vessel 25, as shown in FIG. For this reason, the superconducting filter 11 is mounted in the package 24 and mounted in the vacuum vessel 25. The cooling stage 26 is connected (directly connected) to a refrigerator 27 provided outside the vacuum vessel 25.

Thus, in the present embodiment, the superconducting tunable filter device includes the cooling device 28 including the refrigerator 27 and the cooling stage 26 directly connected to the refrigerator 27.
The cooling device 28 is for cooling the superconducting filter 11 so that the superconducting state of the superconducting filter 11 appears. As the refrigeration apparatus 28, for example, a helium gas circulation type small refrigeration apparatus may be used. The cooling device 28 may use nitrogen as a refrigerant.

The package 24 is provided with an input connector 29 and an output connector 30 as shown in FIGS.
Here, as shown in FIG. 5, the package 24 is mounted on the cooling stage 26 so that the input connector 29 is positioned forward and the output connector 30 is positioned upward. Further, the input connector 29 and the output connector 30 are respectively connected to the input / output feeder 18 of the superconducting filter 11 as shown in FIG.

Further, as shown in FIG. 5, the vacuum container 25 is provided with an input hermetic connector 31 and an output hermetic connector 32.
Here, an output hermetic connector 32 is provided on the upper surface of the vacuum vessel 25, and an input hermetic connector 31 is provided on the side surface of the vacuum vessel 25. The input hermetic connector 31 is connected to the sample 50, and the output hermetic connector 32 is connected to the spectrum analyzer 10.

Further, an input connector 29 provided on the package 24 and an input hermetic connector 31 provided on the vacuum vessel 25 are connected by a coaxial cable 33. Further, the output connector 30 provided in the package 24 and the output hermetic connector 32 provided in the vacuum vessel 25 are connected by a coaxial cable 34.
An output signal (including a basic signal and an intermodulation distortion signal) from the sample 50 is input to the superconducting filter 11 in the package 24 via the input hermetic connector 31, the coaxial cable 33, and the input connector 29. It has become so. Further, only the basic signal in the output signal from the sample 50 is attenuated by the superconducting filter 11 and is output to the spectrum analyzer 10 via the output connector 30, the coaxial cable 34, and the output hermetic connector 32. It is like that.

Further, as shown in FIG. 1, the rod 13 is movably provided in a rod opening 24 </ b> A formed in the package 24.
Here, as shown in FIG. 5, the package 24 has a cooling stage 26 such that one side surface provided with the rod opening 24 </ b> A and the rod 13 provided in the rod opening 24 </ b> A are positioned laterally. Mounted on top.

Then, as shown in FIG. 1, the ground layer 19 of the superconducting filter 11 is in contact with the inside of one side surface of the package 24, and the superconductivity is located at a position corresponding to the rod opening 24A formed in the package 24. The superconducting filter 11 is accommodated in the package 24 so that an opening (slot) 19A formed in the ground layer 19 of the filter 11 is located. Thereby, the rod 13 is inserted into and removed from the opening (ground side slot) 19 formed in the ground layer 19 of the superconducting filter 11, and the size of the opening 19 </ b> A is adjusted to thereby reject the filter characteristics. The width (f ₂ −f ₁ ) can be changed.

As described above, the rejection bandwidth of the filter characteristic can be changed to a wide band without deteriorating the notch characteristic, so that the nonlinear distortion can be measured with a high performance and a wide dynamic range in a wide frequency range.
Further, as shown in FIG. 5, the rod adjustment trimmer 20 connected to the rod 13 is located outside the package 24 and is provided outside the vacuum vessel 25 via a rod 35 having a relatively low thermal conductivity, for example. It is connected to the rod control means 21 (for example, a straight line introduction mechanism control mechanism).

Further, as shown in FIG. 1, the plate 14 is attached to a plate adjustment trimmer 22 movably provided in a plate opening 24 </ b> B formed in the package 24.
Here, as shown in FIG. 5, the package 24 is cooled so that the other side surface provided with the plate opening 24B and the plate adjustment trimmer 22 provided in the plate opening 24B are positioned laterally. It is mounted on the stage 26.

As shown in FIG. 1, the plate 14 accommodated in the package 24 is attached to the tip of the plate adjustment trimmer 22. Accordingly, the plate 14 is moved closer to or away from the resonator pattern 17 of the superconducting filter 11, and the distance between the plate 14 and the resonator pattern 17 is adjusted, whereby the center frequency [f ₀ = (F ₁ + f ₂ ) / 2] can be changed.

As described above, the center frequency of the filter characteristic (that is, the position of the two reject bands) can be changed in a wide band without deteriorating the notch characteristic, so that it is non-linear with high performance and a wide dynamic range in a wide frequency range. Can measure strain.
Here, the center frequency of the filter characteristic of the superconducting filter 11 is preferably in the range of 3 to 6 GHz in order to make use of the low loss of superconductivity. The tunable range can be up to octave, but about 10% (for example, when the center frequency is 5 GHz, a variable amount up to 500 MHz is easily realized.

Further, the plate adjusting trimmer 22 connected to the plate 14 extends to the outside of the package 24 as shown in FIG. Then, as shown in FIG. 5, the plate adjusting trimmer 22 is provided with a plate control means 23 (for example, linear introduction mechanism control) provided outside the vacuum vessel 25 through a rod 36 having a relatively low thermal conductivity, for example. Connected to the mechanism).
Here, a part of the position adjusting means 15 (15A, 15B) is provided in the vacuum container 25, and the remaining part of the position adjusting means 15 (15A, 15B) (especially the control means 21, 23) is disposed outside the vacuum container 25. However, the present invention is not limited to this. For example, all of the position adjusting means 15 (15A, 15B) may be provided in the vacuum vessel 25.

Therefore, according to the superconducting tunable filter device, the non-linear strain measuring device, and the non-linear strain measuring method according to the present embodiment, it is possible to measure the non-linear strain with high accuracy and high dynamic in a wide frequency range with a simple configuration. There is.
In the above-described embodiment, the rod 13 is connected to the rod adjustment trimmer 20 and the rod adjustment trimmer 20 is controlled by the rod control means 21 to adjust the position of the rod 13. It is not something that can be done.

  For example, the rod 13 is connected to a rod adjustment piezo element or a rod adjustment MEMS (Micro Electro Mechanical Systems) element, and the rod adjustment trimmer or the rod adjustment MEMS element is controlled by the rod control means to adjust the position of the rod 13. You may do it. That is, the rod position adjusting means is any one of a rod adjustment trimmer, a rod adjustment piezo element, and a rod adjustment MEMS element connected to the rod 13, and one of a rod adjustment trimmer, a rod adjustment piezo element, and a rod adjustment MEMS element. What is necessary is just to provide the control means for rods for controlling one. When the rod adjusting piezo element is used, the rod control means includes a piezo actuator.

Further, in the above-described embodiment, the plate 14 is connected to the plate adjustment trimmer 22 and the plate adjustment trimmer 22 is controlled by the plate control means 23 to adjust the position of the plate 14. It is not something that can be done.
For example, the plate 14 may be connected to a plate adjustment piezo element or a plate adjustment MEMS element, and the position of the plate 14 may be adjusted by controlling the plate adjustment trimmer or the plate adjustment MEMS element by the plate control means. That is, the plate position adjusting means is any one of a plate adjustment trimmer, a plate adjustment piezo element, and a plate adjustment MEMS element connected to the plate 14, and any one of the plate adjustment trimmer, the plate adjustment piezo element, and the plate adjustment MEMS element. What is necessary is just to provide the control means for plates for controlling one. When the plate adjusting piezo element is used, the plate control means includes a piezo actuator.

  In the above-described embodiment, the rod 13 and the plate 14 are connected to the trimmers 20 and 21, and the trimmers 20 and 21 are controlled by the control means 21 and 23 to adjust the positions of the rod 13 and the plate 14. However, the present invention is not limited to this. For example, a system using a wire may be used. As a wire system, for example, a wire may be attached to the rod 13 and the plate 14 and the positions of the rod 13 and the plate 14 may be adjusted. In this case, the position adjusting means is configured to include a wire.

In the above-described embodiment, a disk pattern is used as the resonator pattern 17 of the superconducting filter 11, but the present invention is not limited to this.
For example, as shown in FIG. 7A, two line patterns 37 and 38 constituting a resonator may be used as the resonator pattern of the superconducting filter 11. In this case, the two line patterns 37 and 38 (resonators) may be disposed adjacent to each other on the surface of the dielectric substrate 40. Here, they are disposed in parallel with a predetermined interval.

Here, it is preferable that the lengths of the two line patterns 37 and 38 are both λ _g / 2, and the distance between the line patterns 37 and 38 is λ _g / 4.
In this case, the input / output feeder 39 may be formed on one end side of the two line patterns 37 and 38 so as to extend in a direction orthogonal to the two line patterns 37 and 38. The input / output feeder 39 may be formed on the surface of the dielectric substrate 40 as a linear conducting wire extending from one end to the other end.

For example, the center frequency of the filter characteristics can be arbitrarily set by adjusting the lengths of the two line patterns 37 and 38.
Further, as shown in FIG. 7B, an opening 41A (here, a circular slot) provided in the ground layer 41 formed on the back surface of the dielectric substrate 40 is provided between the two line patterns 37 and 38. It may be provided at a position corresponding to the space.

For example, by increasing the size of the opening 41A provided in the ground layer 41, the reject bandwidth of the filter characteristics can be widened. On the other hand, the rejection bandwidth can be narrowed by reducing the size of the opening 41A provided in the ground layer 41.
Further, in order to reduce the distortion component from the superconducting filter itself as much as possible, the widths of the line patterns 37 and 38 may be increased.

  Further, for example, as shown in FIG. 8A, as the resonator pattern of the superconducting filter 11, two disk patterns 42 and 43 constituting the resonator may be used. In this case, two disk patterns 42 and 43 (disk resonators) may be disposed adjacent to the surface of the dielectric substrate 45. Here, the input / output is performed so that the distance between the center positions becomes a predetermined distance. They are arranged on both sides with the feeder 44 in between.

Here, the distance between the center positions of the two disk patterns 42 and 43 is preferably λ _g / 4. The input / output feeder 44 may be formed on the surface of the dielectric substrate 45 as a linear conducting wire extending from one end to the other end. Note that λ _g is an intermediate wavelength between the two basic signals.
For example, the center frequency of the filter characteristic can be arbitrarily set by adjusting the diameters of the two disk patterns 42 and 43.

  Further, as shown in FIG. 8B, an opening 46A (here, a circular slot) provided in the ground layer 46 formed on the back surface of the dielectric substrate 45 is provided between the two disk patterns 42 and 43. It may be provided at a position corresponding to the space. For example, the opening 46 </ b> A provided in the ground layer 46 may be provided at a position corresponding to an intermediate position between lines connecting the centers of the two disk patterns 42 and 43.

For example, by increasing the size of the opening 46A provided in the ground layer 46, the reject bandwidth of the filter characteristic can be widened. On the other hand, by reducing the size of the opening 46A provided in the ground layer 46, the reject bandwidth of the filter characteristics can be narrowed.
Further, for example, the rejection bandwidth of the filter characteristics can be narrowed by moving the opening 46A provided in the ground layer 46 away from the centers of the two disk patterns 42 and 43. That is, by moving the opening 46A provided at a position corresponding to the middle position of the line connecting the centers of the two disk patterns 42 and 43 in a direction orthogonal to the line, the reject bandwidth of the filter characteristic is increased. Can be narrowed. In short, by reducing the opening 46A provided in the ground layer 46 from the center of the two disk patterns 42 and 43 or approaching the center of the two disk patterns 42 and 43, the reject bandwidth can be narrowed or widened. You can do it.

Further, the configuration of the superconducting filter 11 is not limited to that of the above-described embodiment.
That is, for example, as shown in FIG. 9, the superconducting filter 11 is tuned with the waveguide 47, the bandwidth adjusting hole 48A used for tuning the rejection bandwidth of the filter characteristics, and the center frequency of the filter characteristics. It may be configured to include a cavity 48 having a center frequency adjusting hole 48B used for the purpose.

In this case, a bandwidth adjusting rod for tuning the reject bandwidth of the filter characteristic of the superconducting filter 11 and a center frequency adjusting rod for tuning the center frequency of the filter characteristic of the superconducting filter 11 are used.
Then, the position adjusting means adjusts the position of the bandwidth adjusting rod so that the size of the bandwidth adjusting hole 48A is adjusted, and at the same time adjusts the size of the center frequency adjusting hole 48B. The position of the frequency adjusting rod may be adjusted.

In particular, in order to minimize the distortion component from the superconducting filter itself, it is preferable to use a metal cavity using any one of the superconductor materials mentioned in the above embodiment.
Note that the present invention is not limited to the configurations described in the above-described embodiments and modifications, and various modifications can be made without departing from the spirit of the present invention.
Hereinafter, additional notes will be disclosed regarding the above-described embodiment and modifications.

(Appendix 1)
Band rejection type superconducting filter,
A rod for tuning the superconducting filter;
A superconducting tunable filter device comprising: a rod position adjusting means for adjusting the position of the rod with respect to the superconducting filter.

(Appendix 2)
Band rejection type superconducting filter,
A plate for tuning the superconducting filter;
A superconducting tunable filter device comprising plate position adjusting means for adjusting the position of the plate with respect to the superconducting filter.

(Appendix 3)
The superconducting filter includes a dielectric substrate, a resonator pattern and an input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a superconducting material formed on the back surface of the dielectric substrate. The superconducting tunable filter device according to appendix 1 or 2, further comprising: a ground layer having an opening for forming a filter characteristic having a reject band.

(Appendix 4)
A plate for tuning the center frequency of the filter characteristic of the superconducting filter;
A plate position adjusting means for adjusting the position of the plate with respect to the resonator pattern;
The rod is a rod for tuning the reject bandwidth of the filter characteristic of the superconducting filter,
The superconducting tunable filter device according to appendix 1 or 3, wherein the rod position adjusting means adjusts the position of the rod so that the size of the opening is adjusted.

(Appendix 5)
The superconducting filter has a waveguide, a bandwidth adjusting hole used for tuning the reject bandwidth of the filter characteristic, and a center frequency adjusting hole used for tuning the center frequency of the filter characteristic. And
The rod is a bandwidth adjusting rod for tuning the reject bandwidth of the filter characteristic of the superconducting filter, and a center frequency adjusting rod for tuning the center frequency of the filter characteristic of the superconducting filter. ,
The rod position adjusting means adjusts the position of the bandwidth adjusting rod so that the size of the bandwidth adjusting hole is adjusted, and adjusts the size of the center frequency adjusting hole. The superconducting tunable filter device according to appendix 1 or 3, wherein the position of the center frequency adjusting rod is adjusted.

(Appendix 6)
A cooling device for cooling the superconducting filter;
The superconducting tunable filter device according to any one of appendices 1 to 5, wherein the superconducting filter is mounted in a vacuum vessel.
(Appendix 7)
The rod position adjusting means includes any one of a rod adjustment trimmer, a rod adjustment piezo element, and a rod adjustment MEMS element connected to the rod, and the rod adjustment trimmer, the rod adjustment piezo element, and the rod adjustment MEMS element. The superconducting tunable filter device according to any one of appendices 1, 3 to 6, further comprising: a rod control means for controlling any one of the rods.

(Appendix 8)
The plate position adjusting means includes any one of a plate adjustment trimmer, a plate adjustment piezo element, and a plate adjustment MEMS element connected to the plate, and the plate adjustment trimmer, the plate adjustment piezo element, and the plate adjustment MEMS element. The superconducting tunable filter device according to any one of appendices 2, 4, and 6, comprising a plate control means for controlling any one of the plates.

(Appendix 9)
A non-linear distortion measuring apparatus that inputs two basic signals of different frequencies to a sample and measures an intermodulation distortion signal caused by the non-linearity of the sample,
A superconducting tunable filter device for attenuating only the fundamental signal among the fundamental signal output from the sample and an intermodulation distortion signal generated by nonlinearity of the sample;
The superconducting tunable filter device is
Band rejection type superconducting filter,
A rod for tuning the superconducting filter;
A non-linear strain measuring device comprising: a rod position adjusting means for adjusting the position of the rod with respect to the superconducting filter.

(Appendix 10)
Input two basic signals of different frequencies into the sample,
Attenuating only the fundamental signal among the fundamental signal output from the sample and the intermodulation distortion signal generated by the nonlinearity of the sample by a superconducting tunable filter device,
A non-linear distortion measurement method for measuring the intermodulation distortion signal,
Set the frequency of two basic signals according to the sample,
A non-linear distortion measuring method comprising adjusting a center frequency and a reject bandwidth of a filter characteristic of the superconducting tunable filter device according to the frequency of the two basic signals.

DESCRIPTION OF SYMBOLS 1 Superconductivity tunable filter apparatus 2 1st signal source 3 2nd signal source 4 1st power amplifier 5 2nd power amplifier 6 1st isolator 7 2nd isolator 8 3 dB coupler 9 3rd isolator 10 Spectrum analyzer 11 Band rejection type Superconducting filter 12 Tunable structure 13 Rod 14 Plate 15 Position adjusting means 15A Rod position adjusting means 15B Plate position adjusting means 16 Dielectric substrate 17 Resonator pattern 18 Input / output feeder 19 Ground layer 19A Opening (slot)
20 Rod Adjustment Trimmer 21 Rod Control Unit 22 Plate Adjustment Trimmer 23 Plate Control Unit 24 Package 24A Rod Opening 24B Plate Opening 25 Vacuum Container 26 Cooling Stage 27 Refrigerator 28 Cooling Device 29 Input Connector 30 Output Connector 31 Hermetic connector for input 32 Hermetic connector for output 33, 34 Coaxial cable 35, 36 Bar having relatively low thermal conductivity 37, 38 Line pattern 39 Input / output feeder 40 Dielectric substrate 41 Ground layer 41A Opening (slot)
42, 43 Disc pattern 44 Input / output feeder 45 Dielectric substrate 46 Ground layer 46A Opening (slot)
47 Waveguide 48 Cavity 48A Bandwidth adjustment hole 48B Center frequency adjustment hole 50 samples

Claims (4)

A dielectric substrate, a resonator pattern and an input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a filter characteristic having two reject bands formed of a superconducting material on the back surface of the dielectric substrate A band-rejection type superconducting filter comprising a ground layer having an opening for forming
A rod for tuning the reject bandwidth of the filter characteristics of the superconducting filter;
A superconducting tunable filter device comprising: a rod position adjusting means for adjusting the position of the rod with respect to the superconducting filter so that the size of the opening is adjusted . A plate for tuning the center frequency of the filter characteristics before Symbol superconducting filter,
The superconducting tunable filter device according to claim 1, further comprising plate position adjusting means for adjusting the position of the plate with respect to the resonator pattern . A non-linear distortion measuring apparatus that inputs two basic signals of different frequencies to a sample and measures an intermodulation distortion signal caused by the non-linearity of the sample,
A superconducting tunable filter device for attenuating only the fundamental signal among the fundamental signal output from the sample and an intermodulation distortion signal generated by nonlinearity of the sample;
The superconducting tunable filter device is
A dielectric substrate, a resonator pattern and an input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a filter characteristic having two reject bands formed of a superconducting material on the back surface of the dielectric substrate A band-rejection type superconducting filter comprising a ground layer having an opening for forming
A rod for tuning the reject bandwidth of the filter characteristics of the superconducting filter;
A non-linear strain measuring device comprising: a rod position adjusting means for adjusting a position of the rod with respect to the superconducting filter so that a size of the opening is adjusted . Input two basic signals of different frequencies into the sample,
A dielectric substrate, a resonator pattern and an input / output feeder formed of a superconducting material on the surface of the dielectric substrate, and a filter characteristic having two reject bands formed of a superconducting material on the back surface of the dielectric substrate A band-rejection type superconducting filter comprising a ground layer having an opening for forming a rod, a rod for tuning a reject bandwidth of a filter characteristic of the superconducting filter, and a size of the opening The basic signal output from the sample and the non-linearity of the sample by a superconducting tunable filter device comprising a rod position adjusting means for adjusting the position of the rod with respect to the superconducting filter to be adjusted to attenuate only the basic signal of the intermodulation distortion signal caused by,
A non-linear distortion measurement method for measuring the intermodulation distortion signal,
Set the frequency of two basic signals according to the sample,
A non-linear distortion measuring method comprising adjusting a center frequency and a reject bandwidth of a filter characteristic of the superconducting tunable filter device according to the frequency of the two basic signals.

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