JPH04336801A - Automatic setting device for resonance frequency of resonator - Google Patents

Abstract

PURPOSE:To set a resonance frequency of a resonator to a desired setting value automatically with excellent precision by calculating the resonance frequency of the resonator and controlling the resonance frequency of the resonator based on the calculated resonance frequency. CONSTITUTION:An MPU 40 applies switching control to switches SW1, SW2 and receives data fm of an oscillated frequency measured by a frequency counter 35, and calculates an equivalent phase theta1 of a dielectric resonator 10 based on the received oscillating frequency data fm. Then the MPU 40 calculates a resonance frequency f0 of the dielectric resonator 10 based on a known load Q and the calculated equivalent phase theta1 of the dielectric resonator 10. The data is displayed on a CRT display device 41 and a pulse drive signal is outputted to a stepping motor 51 so that the resonance frequency f0 of the dielectric resonator 10 reaches a setting frequency f01 thereby implementing the automatic setting processing.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention automatically sets the resonant frequency of the resonator to the set frequency based on the frequency at which the resonant frequency of the resonator should be set (hereinafter referred to as set frequency), which is input in advance. The present invention relates to an automatic setting device for the resonant frequency of a resonator, and an automatic resonant frequency setting type resonator.

0002

2. Description of the Related Art FIG. 9 is a block diagram of a conventional self-tuning resonator proposed in Japanese Patent Application Laid-Open No. 1-105601.

In FIG. 9, this conventional self-tuning resonator includes an isolator 101 that allows an input high-frequency signal to pass in one direction and is provided with a reflected power coupling terminal 111, and an isolator 101 that passes an input high-frequency signal in one direction. a resonator 102 that operates as a bandpass filter that performs bandpass filtering;
A drive mechanism 103 that changes the resonant frequency of the resonator 102 by moving a resonant frequency adjustment element (not shown) in the resonator 102 and a high frequency signal output from the reflected power coupling element 111 of the isolator 101 The control circuit 104 detects the signal using the diode D1 and controls the drive mechanism 103 based on the detected signal.

In this self-tuning resonator, when a certain high frequency signal is passed through the resonator, the high frequency signal (
Hereinafter, this will be referred to as a reflected signal. ) is the level of the resonator 102
The control circuit 104 controls the drive mechanism 103 based on the reflected signal so that the level of the reflected signal becomes the minimum, utilizing the fact that the level of the reflected signal is minimized at the resonance frequency. Thereby, the center frequency of the bandpass filter, which is approximately equal to the resonant frequency of the resonator 102, can be tuned to the frequency of the high frequency signal passing through the isolator 101.

[0005]

[Problems to be Solved by the Invention] However, in the automatic tuning type resonator of the first conventional example described above, the above-mentioned tuning operation is performed by utilizing the fact that the level of the reflected signal is minimum at the resonant frequency of the resonator 102. For example, when the auto-tuning resonator shown in Fig. 9 is used in an antenna sharing device, if a wraparound signal from another channel is input to the auto-tuning resonator, the above tuning operation will be performed accurately. The problem was that it was not possible to do so.

A first object of the present invention is to solve the above-mentioned problems, and to provide a resonator that can automatically set the resonant frequency of a resonator to a desired setting value with better accuracy than in the conventional example. An object of the present invention is to provide an automatic setting device for the resonant frequency of a device.

A second object of the present invention is to provide an automatic resonant frequency setting type resonator that can automatically set the resonant frequency to a desired setting value with better accuracy than conventional examples. It is about providing.

[0008]

[Means for Solving the Problems] An automatic setting device for resonant frequency of a resonator according to claim 1 of the present invention is provided with an amplifying means, has a predetermined load Q, and is capable of changing the resonant frequency. an oscillation loop circuit electrically connected to the resonator and having a predetermined transmission phase; a frequency measurement means for measuring the oscillation frequency of an oscillation signal generated in the oscillation loop circuit; and an oscillation frequency measured by the frequency measurement means. and the transmission phase of the oscillation loop circuit and the load Q of the resonator.
calculation means for calculating the resonant frequency of the resonator based on the resonant frequency of the resonator based on the resonant frequency of the resonator calculated by the calculation means so that the resonant frequency of the resonator becomes a set frequency input in advance; The present invention is characterized by comprising a control means for controlling the resonant frequency of the resonator.

[0009] The automatic resonant frequency setting device of a resonator according to claim 2 is the resonator resonant frequency automatic setting device according to claim 1, wherein the resonator has an element constant that determines its resonant frequency. The control means includes an element constant changing means for changing the element constant of the frequency variable element of the resonator, and the resonance of the resonator calculated by the calculating means. Based on the frequency, the frequency variable element of the resonator is controlled by controlling the element constant changing means so that the absolute value of the difference between the calculated resonant frequency of the resonator and the set frequency is less than a predetermined value. and a frequency control means for controlling the resonant frequency of the resonator so that the resonant frequency of the resonator becomes the set frequency by changing the element constant of the resonator.

Furthermore, the resonant frequency automatic setting type resonator according to claim 3 of the present invention includes a resonator having a predetermined load Q and whose resonant frequency can be changed;
It is characterized by comprising the automatic setting device described above.

[0011]

[Operation] The automatic setting device for resonant frequency of a resonator according to claim 1 is provided with an amplifying means, electrically connected to a resonator having a predetermined load Q and capable of changing the resonant frequency. , an oscillation loop circuit having a predetermined transmission phase is provided, and the frequency measuring means measures the oscillation frequency of the oscillation signal generated in the oscillation loop circuit, and then
The calculating means calculates the resonant frequency of the resonator based on the oscillation frequency measured by the frequency measuring means, the transmission phase of the oscillation loop circuit, and the load Q of the resonator. Next, the control means controls the resonant frequency of the resonator so that the resonant frequency of the resonator becomes a preset frequency input based on the resonant frequency of the resonator calculated by the calculation means. This allows for a simple configuration and better accuracy than conventional examples.
The resonant frequency of the resonator can be automatically set to the set frequency.

Further, in the automatic setting device for resonant frequency of a resonator according to claim 2, in the automatic setting device for resonant frequency of a resonator according to claim 1, preferably, the resonator has a resonant frequency of The control means includes an element constant changing means for changing the element constant of the frequency variable element of the resonator, and a frequency variable element that is capable of changing an element constant that determines the Based on the resonant frequency of the resonator, the element constant changing means is controlled so that the absolute value of the difference between the calculated resonant frequency of the resonator and the set frequency is less than a predetermined value. and a frequency control means for controlling the resonant frequency of the resonator so that the resonant frequency of the resonator becomes the set frequency by changing an element constant of a variable frequency element of the resonator.

Furthermore, in the resonant frequency automatic setting type resonator according to claim 3 of the present invention, there is provided a resonator having a predetermined load Q and whose resonant frequency can be changed; A resonant frequency automatic setting type that can automatically set the resonant frequency of the resonator to the set frequency with a simple configuration and with better accuracy than conventional examples. A resonator can be constructed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An automatic setting device for resonant frequency of a dielectric resonator according to an embodiment of the present invention will be described below in the following order with reference to the drawings. (1) Configuration of automatic setting device for resonant frequency of dielectric resonator (2) Measuring principle of resonant frequency of dielectric resonator (3) Control flow of automatic setting process of automatic setting device (4) Modification example of drive mechanism (5) Other examples

The automatic setting device of this embodiment has a known load Q.
The dielectric resonator 10 having a resonant frequency to be set is electrically connected to an oscillation loop circuit including an amplifier 33, oscillated at an oscillation frequency fm, the oscillation frequency fm is measured, and the measured oscillation frequency is The resonant frequency f0 of the dielectric resonator 10 is determined based on fm and the set frequency f01 input in advance.
is automatically set to the set frequency f01.

(1) Configuration of automatic setting device for resonant frequency of dielectric resonator FIG. 1 is a block diagram of an automatic setting device for resonant frequency of a dielectric resonator 10 which is an embodiment of the present invention, and FIG. Figure 1
FIG. 2 is a vertical cross-sectional view of a dielectric resonator 10 and a shield case 13 housing it. Here, the dielectric resonator 10 has a known load Q (QL).

This automatic setting device has a filtering operation mode in which the dielectric resonator 10 operates as a bandpass filter;
It has two operation modes: an automatic setting mode in which automatic setting processing is performed to automatically set the resonant frequency f0 of the dielectric resonator 10 to the set frequency f01.

As shown in FIGS. 1 and 2, the dielectric resonator 11 of the cylindrical dielectric resonator 10 whose resonant frequency is to be set is located at the center of the cylindrical shield case 13. Support base 1 having the same linear expansion coefficient as the resonator 11
It is placed on 4. This dielectric resonator 11 is made of, for example, TiO2 as a main component and MgO, BaO, Zr.
The dielectric resonator 10 of this embodiment, which is a ceramic dielectric resonator mixed with an oxide such as O2, and includes the dielectric resonator 11, resonates from about 870 MHz to about 895 MHz in the fundamental mode TE01δ mode. frequency f
has 0. Further, inside the cylinder of the dielectric resonator 11, a cylindrical dielectric tuning element 12 is supported by a shaft 15 so as to be movable in the axial direction of the dielectric resonator 11. A microprocessor unit (hereinafter referred to as MPU) 40, which is a control circuit of the automatic setting device, outputs a predetermined number of drive pulse signals to the stepping motor 51 via the motor drive circuit 50, causing the stepping motor 51 to rotate. By transmitting the driving force to the shaft 15 via the drive mechanism 52, the shaft 15 is moved in the direction of arrow A1. By this movement of the shaft 15, the dielectric tuning element 12 is moved to the dielectric resonator 1.
By moving the dielectric resonator 10 within the gradient of the electric field, the resonant frequency f0 of the dielectric resonator 10 can be finely adjusted.

FIG. 4 is a graph showing the relationship between the position of the dielectric tuning element 12 of the dielectric resonator 10 of FIG. 2 and the resonant frequency f0 of the dielectric resonator 10. Here, g is the distance from the top surface of the dielectric tuning element 12 to the inside top surface of the shield case 13. As is clear from FIG. 4, by moving the dielectric tuning element 12 away from the top surface of the shield case 13, that is, by increasing the distance g, the resonant frequency f0 of the dielectric resonator 11 approximately changes with the distance g. changes in inverse proportion. Therefore, if the resonant frequency when the dielectric resonator 11 is at a certain position is f0, and the set frequency to be set in the dielectric resonator 10 is f01, then the resonant frequency f0 of the dielectric resonator 10 is set to the above set frequency. The distance lm that the dielectric tuning element 12 should be moved to set f01 is expressed by the following "Equation 1".

[0020]

[Equation 1] lm=k(f0-f01)

Here, k is a constant determined from the graph of FIG. In this embodiment, as will be described in detail later, a pulse drive signal with a number of pulses corresponding to the moving distance lm calculated using "Equation 1" is sent from the MPU 40 to the motor drive circuit 5.
0 to the stepping motor 51 to move the dielectric tuning element 12 in the dielectric resonator 10, thereby making the resonant frequency f0 of the dielectric resonator 10 approximately equal to the set frequency f01. , dielectric resonator 1
Automatic resonant frequency setting processing for 0 can be performed. In addition, the moving distance lm calculated using the above "Equation 1"
is a positive number, a pulse drive signal of positive polarity corresponding to the moving distance lm is input to the stepping motor 51, and at this time, the dielectric tuning element 12 is connected to the dielectric resonator 11.
As a result, the capacitance component of the dielectric resonator 10 increases, and its resonant frequency decreases. On the other hand, the moving distance l calculated using the above "Equation 1"
When m is a negative number, a pulse drive signal of negative polarity corresponding to the moving distance lm is input to the stepping motor 51, and at this time, the dielectric tuning element 12
1, thereby decreasing the capacitance component of the dielectric resonator 10 and increasing its resonant frequency.

FIG. 3 is a longitudinal sectional view of a drive mechanism 52 provided between the dielectric resonator 10 and the stepping motor 51.

As shown in FIG. 3, the drive mechanism 52 includes a shaft coupling 60, two feed screws 61, and two feed screws 61, which are provided concentrically with the shaft 15 and the shaft 51a of the stepping motor 51, respectively, in the drive mechanism housing 52h. 63. The shaft 15 of the dielectric resonator 10 is the feed screw 63
is interpolated and fixed. On the other hand, stepping motor 5
The shaft 51a of No. 1 is connected to the feed screw 6 via the shaft coupling 60.
It is connected to a shaft 61a formed concentrically with the cylindrical portion 61c of No. 1 and protruding from the end surface of the cylindrical portion 61c. The cylindrical portion 61c of the feed screw 61 is rotatably supported by a bearing 62 in a cylindrical portion 52hi inserted into and fixed to the housing 52h of the drive mechanism 52 so as to be concentric with the shaft 15. A screw formed on the inner surface of the cylindrical portion 61c of the feed screw 61 and a screw formed on the outer peripheral surface of the feed screw 63 are screwed together. The upper surface of the drive mechanism housing 52h and the lower surface of the shield case 13 are bonded to each other and integrated. As a result, when the feed screw 61 is rotated, the feed screw 63 moves in the longitudinal direction of the shaft 15 in response to the rotation, and at this time, the shaft 15 moves in the direction of arrow A1.

Note that the shaft 15 of the dielectric resonator 10 is applied in the direction toward the stepping motor 51 by a pressurizing spring inserted in the cylindrical portion 13a of the shield case provided on the opposite side of the drive mechanism 52. At the same time, rotation of the shaft 15 is prevented by the rotation stopper 90 inserted into the cylindrical portion 13a.

In the drive mechanism 52 configured as described above, when the stepping motor 51 is driven and its shaft 51a rotates, the rotational driving force is transmitted to the shaft coupling 60.
This is transmitted to the shaft 15 of the dielectric resonator 10 via the feed screw 61 and the feed screw 63, and the shaft 15 moves in the direction of arrow A1.

Returning to the explanation of FIGS. 1 and 2, the shield case 13 has an electromagnetic shield on the outer surface of a cylindrical casing made of ceramic having the same coefficient of linear expansion as the dielectric resonator 11. For this reason, it is constructed by baking silver electrodes. As shown in Figure 1, this shield case 1
The inner surfaces of the cylinders 3 and 9 apart from each other around the center of the cylinder.
For example, one-turn coils 21 and 22 for signal input/output are installed at four positions separated by an angle of 0 degrees so as to couple with the magnetic field H of the dielectric resonator 11 as shown in FIG.
, 23, 24 are provided. Here, coils 21 and 22 used in the filter operation mode are provided facing each other with the dielectric resonator 11 in between, and coils 23 and 24 used in the automatic setting mode are provided opposite to each other with the dielectric resonator 11 in between.
are placed facing each other with the two in between.

In the filter operation mode, the switch SW1 is turned on and the switch SW2 is turned off, and a signal in the approximately 800 MHz band output from the high frequency signal generator 1 is sent to the coil 21 via the input terminal T1 and the switch SW1. After being input to the dielectric resonator 10, the input signal is filtered by the dielectric resonator 10. The filtered signal is output from the coil 22 to the load 2 via the output terminal T2. On the other hand, in the automatic setting mode, the switch SW1 is turned off and the switch SW2 is turned on. At this time, the coils 23, 2
An oscillation signal is generated in an oscillation loop circuit that is connected between the two terminals and is configured such that oscillation conditions, which will be described in detail later, are satisfied. When switch SW2 is turned on, the oscillation loop circuit shown in FIG. Port 34a of sexual coupler 34,
The signal is output to the coil 23 via the transmission line connected between the terminals 34b and the switch SW2. Note that the two switches SW1 and SW2 mentioned above are connected to the MPU4, as will be described in detail later.
Switching is controlled by 0.

Ports 34a, 3 of the directional coupler 34
A port 34d that detects an oscillation signal, which is a traveling wave passing through the transmission line between 4b and 4b, is connected to a frequency counter 35, and a port 34d that detects a reflected wave passing through the transmission line.
c is terminated by a load 34e with a predetermined characteristic impedance. This frequency counter 35 is connected to the port 34
The frequency of the oscillation signal detected at point d is measured, and data fm of the measured frequency is output to the MPU 40. Further, a keyboard 42 for inputting the set frequency f01 is connected to the MPU 40, and when the set frequency f01 is input using the keyboard 42, the data is outputted from the keyboard 42 to the MPU 40.

The MPU 40 controls the automatic setting device and sets the resonance frequency f0 of the dielectric resonator 10 to the set frequency f.
A CPU (not shown) that executes an automatic setting process for automatically setting 01, a control program for controlling the automatic setting device, and data necessary for executing the above control program are stored. ROM (not shown) and RA used as working memory of the CPU
M (not shown), switches SW1, SW2, frequency counter 35, CRT display 41, and keyboard 4
2 and an input/output port circuit (not shown) connected to the motor drive circuit 50 and operating as an interface circuit. As will be described in detail later, this MPU 40 switches and controls the switches SW1 and SW2, and also controls the oscillation frequency data f measured from the frequency counter 35.
m is received, the transmission phase θ1 of the dielectric resonator 10 is calculated based on the received oscillation frequency data fm, and the transmission phase θ1 is calculated based on the known load Q (QL) of the dielectric resonator 10 and the transmission phase θ1 calculated above. Based on the resonant frequency f0 of the dielectric resonator 10
is calculated and these data are displayed on the CRT display 41.
The automatic setting process is performed by outputting a pulse drive signal to the stepping motor 51 so that the resonant frequency f0 of the dielectric resonator 10 becomes the set frequency f01.

(2) Principle of Measuring the Resonant Frequency of a Dielectric Resonator The oscillation conditions in the oscillation loop circuit shown in FIG. 1 are expressed by the following "Equation 2" and "Equation 3".

[0031]

[Formula 2] Re(A・β1)=1

[Equation 3] Im(A・β1)=0

[0032] Here, A is the amplification degree of the amplifier 33,
β1 is the amount of feedback in the oscillation loop circuit.

In the above oscillation loop circuit, the above ``Math.
” When the oscillation condition expressed by “Equation 3” is satisfied, an oscillation signal having a certain oscillation frequency fm is generated. The oscillation loop circuit shown in FIG. 1 in this embodiment has a predetermined transmission phase so that the above-mentioned "Equation 2" and "Equation 3" are satisfied.

In the above oscillation loop circuit, if the transmission phase of the devices and lines other than the dielectric resonator 10 at an arbitrary frequency fa close to the resonant frequency f0 of the dielectric resonator 10 is Θ1 [rad], the dielectric resonance The transmission phase θ1 of the device 10 is expressed by the following “Equation 4”.

[0035]

[Math 4]

Here, n is an integer, and the transmission phase Θ
1 is a device constant that can be measured in advance with a network analyzer or the like in the oscillation loop circuit.

As is clear from the above equation 4, by measuring the oscillation frequency fm in the oscillation loop circuit, the dielectric resonator 10 in the oscillation loop circuit can be
The transmission phase θ1 of can be determined.

When the resonant frequency of the resonator is f0, generally the following relationship as shown in Equation 5 holds between the transmission phase θ of the resonator and its load Q (QL).

[0039]

[Math 5]

Therefore, when the above oscillation loop circuit is applied to the above "Equation 5", the following "Equation 6" is obtained.

[0041]

[Math 6]

From the above "Equation 6", the resonant frequency f0 is determined by the following "
It is represented by the number 7.

[0043]

[Math 7]

Here, the dimensionless constant F1 is the following "Math. 8"
It is expressed as

[0045]

[Math. 8]

Therefore, after measuring the oscillation frequency fm of the oscillation signal generated in the oscillation loop circuit, the transmission phase θ1 of the dielectric resonator 10 is determined by substituting the measured frequency fm into the above ``Equation 4''. can be calculated. Next, after calculating the value of the constant F1 by substituting the calculated transmission phase θ1 and the known load Q (QL) of the dielectric resonator 10 into the above equation 8, the value of the constant F1 calculated above is calculated. The resonant frequency f0 of the dielectric resonator 10 can be calculated and measured by substituting the value into the above "Equation 7".

(3) Control flow of automatic setting processing of automatic setting device FIG. 5 is a flowchart showing a control flow of automatic setting processing in automatic setting mode of the automatic setting device of FIG.
The measurement flow of the automatic setting device will be explained with reference to .

First, in step S1, the set frequency f01 of the resonant frequency of the dielectric resonator 10 is set to
2, the data is input from the keyboard 42 to the MPU 40, and at this time the data is stored in the RAM. Next, in step S2, the switch S
W1 is turned off, switch SW2 is turned on, the automatic setting device is set to automatic setting mode, and the oscillation loop circuit is connected between coils 23 and 24. Furthermore, in step S3, the oscillation frequency fm of the oscillation signal generated in the oscillation loop circuit is measured by the frequency counter 35, and the data fm is stored in the RAM in the MPU 40.
is stored as the oscillation frequency fm.

Next, in step S4, the transmission phase θ1 of the dielectric resonator 10 is calculated by substituting the measured oscillation frequency fm into the above equation 4, and the calculated result is stored in the RAM. After substituting the above calculated transmission phase θ1 into the above “Equation 8” and calculating the value of the above constant F1,
The value of the constant F1 calculated above is substituted into the above "Equation 7" to calculate the resonant frequency f0 of the dielectric resonator 10, and the calculated result is stored in the RAM and displayed on the CRT display 41.

Next, in step S5, the dielectric tuning element 12 is determined using the above "Equation 1" based on the current resonance frequency f0 calculated in the above step S4 and the set frequency f01 input in the above step S1. The moving distance lm is calculated, and in step S6, a pulse drive signal corresponding to the calculated moving distance lm is outputted to the stepping motor 51 via the motor drive circuit 50. As a result, the dielectric tuning element 12 is moved by the movement distance lm calculated above. Further, in step S7, the oscillation frequency fm of the oscillation signal generated in the oscillation loop circuit is measured by the frequency counter 35, and the data fm is stored in the RAM in the MPU 40 at the oscillation frequency fm.
Then, in step S8, similarly to step S4, the resonant frequency f0 of the dielectric resonator 10 is calculated based on the oscillation frequency fm measured in step S7, and the calculated result is It is stored in the RAM and displayed on the CRT display 41.

Furthermore, in step S9, the absolute value of the difference between the current resonance frequency f0 calculated in step S8 and the set frequency f01 input in step S1 is calculated, and the absolute value is set to a predetermined value. is compared with the setting error Δf. Here, when the absolute value of the calculated difference is smaller than the setting error Δf (YES in step 9), assuming that the resonant frequency f0 of the dielectric resonator 10 roughly matches the setting frequency f01, step In S10, the switch SW2 is turned off and the switch SW1 is turned on to complete the automatic setting process and set the operation mode from the automatic setting mode to the filtering operation mode. On the other hand, the absolute value of the calculated difference is the setting error Δf
In the above case (NO in step 9), step S5
The process returns to Steps S5 to S8, and these processes are executed until the absolute value of the calculated difference becomes less than the setting error Δf in Step S9.

As explained above, the dielectric resonator 10 to be measured having a known load Q is electrically connected to the oscillation loop circuit including the amplifier 33 and oscillated at the oscillation frequency fm. The resonant frequency f of the dielectric resonator 10 is determined based on the measured oscillation frequency fm.
0 is calculated to measure the resonant frequency f0 of the dielectric resonator 10, so the resonant frequency f0 of the dielectric resonator 10 with a known load Q can be accurately measured with higher accuracy than in the conventional example. be able to. Furthermore, the distance lm to which the dielectric tuning element 12 should be moved is determined based on the accurately measured resonance frequency f0 and the pre-input set frequency f01.
Based on the calculated moving distance lm, the stepping motor 51 is driven to move the dielectric tuning element 12, and the resonant frequency f0 measured by the above calculation and the above pre-input setting are calculated using Equation 1. The above-described process is repeated until the absolute value of the difference from the frequency f01 reaches the predetermined setting error Δf, so that the dielectric resonator 10 resonates with improved accuracy with a relatively small error that is less than the setting error Δf. A process for setting the frequency f0 can be executed.

(4) Modified Example of Drive Mechanism FIG. 6 shows the drive mechanism 52 of the stepping motor 51 in FIG.
FIG. 6 is a vertical cross-sectional view (a) and a side view (b) showing a first modified example 52a of the drive mechanism housing 52a in FIG.
h, its cylindrical portion 52hi, and the details inside the dielectric resonator 10 are the same as those in FIG. 3, so they are omitted.

As shown in FIG. 6, the drive mechanism 52a of the first modification includes feed screws 63, 64 and bevel gears 67, 6.
8. The shaft 15 of the dielectric resonator 10 is inserted into the feed screw 63 and fixed, while the shaft 51a of the stepping motor 51 is inserted into the bevel gear 68 and fixed. The outer peripheral surface of the feed screw 64 is rotatably supported within the cylindrical portion 52hi of the drive mechanism housing 52h by a bearing 65, and the outer peripheral surface of the bevel gear 67 is rotatably supported within the drive mechanism housing 52h.
The inner circumferential surface of the feed screw 7 and the outer circumferential surface of the feed screw 65 are bonded and integrated. A thread formed on the inner circumferential surface of the feed screw 64 is threadedly engaged with a thread formed on the outer circumferential surface of the feed screw 63, and a thread formed on the outer circumferential side of the bevel gear 67 and a screw formed on the outer circumferential side of the bevel gear 68 are engaged with each other. The two screws are screwed together. In the drive mechanism 52a configured as described above, when the stepping motor 51 is rotated, the bevel gear 68 connected to the shaft 51a rotates, and accordingly the bevel gear 67 and the feed screw 64 rotate. Accordingly, the feed screw 63 rotates, and the shaft 15 moves in its longitudinal direction.

FIG. 7 is a side view (a) showing a second modified example 52b of the drive mechanism 52 of the stepping motor 51 in FIG.
and a vertical cross-sectional view (b). In FIG. 7, details of the drive mechanism housing 52h, its cylindrical portion 52hi, and the interior of the dielectric resonator 10 are omitted because they are the same as in FIG. 3.

As shown in FIG. 7, the drive mechanism 52b of the second modification includes feed screws 63, 70 and spur gears 72, 73.
Equipped with The shaft 15 of the dielectric resonator 10 is inserted into the feed screw 63 and fixed, while the shaft 51a of the stepping motor 51 is inserted into the spur gear 73 and fixed. The outer circumferential surface of the feed screw 70 is rotatably supported within the drive mechanism housing 52h by a bearing 71, and the inner circumferential surface of the spur gear 72 and the outer circumferential surface of the feed screw 70 are bonded and integrated. A screw formed on the inner circumferential surface of the feed screw 70 is threadedly engaged with a screw formed on the outer circumferential surface of the feed screw 63,
A screw formed on the outer peripheral surface of the spur gear 72 and a screw formed on the outer peripheral surface of the spur gear 73 are screwed together. In the drive mechanism 52b configured as described above, when the stepping motor 51 is rotated, the spur gear 73 connected to the shaft 51a rotates, and the spur gear 72 and the feed screw 70 rotate accordingly. Accordingly, the feed screw 63 rotates, and the shaft 15 moves in its longitudinal direction.

FIG. 8 is a side view (a) showing a third modification 52c of the drive mechanism 52 of the stepping motor 51 in FIG.
and a vertical cross-sectional view (b). In FIG. 8, details of the drive mechanism housing 52h, its cylindrical portion 52hi, and the inside of the dielectric resonator 10 are omitted because they are the same as in FIG. 3.

As shown in FIG. 8, the drive mechanism 52c of the third modification includes feed screws 63, 70 and a timing gear 8.
0,81, and a timing belt 82. The shaft 15 of the dielectric resonator 10 is inserted into and fixed to the feed screw 63, while the shaft 5 of the stepping motor 51 is inserted into the feed screw 63 and fixed.
1a is inserted into the timing gear 81 and fixed. The outer circumferential surface of the feed screw 70 is rotatably supported within the drive mechanism housing 52h by a bearing 71, and the inner circumferential surface of the timing gear 80 and the outer circumferential surface of the feed screw 70 are bonded and integrated. A screw formed on the inner circumferential surface of the feed screw 70 is threadedly engaged with a screw formed on the outer circumferential surface of the feed screw 63,
A timing belt 82 is stretched between timing gear 80 and timing gear 81. In the drive mechanism 52c configured as described above, when the stepping motor 51 is rotated, the timing gear 81 connected to the shaft 51a rotates, and accordingly, the timing gear 80 and the feed screw are connected via the timing belt 82. 70
rotates, the feed screw 63 rotates accordingly, and the shaft 15 moves in its longitudinal direction.

(5) Other Embodiments In the above embodiments, automatic resonant frequency adjustment for automatically setting the resonant frequency of the dielectric resonator 10 having a known load Q to a predetermined set frequency Although a setting device is described, the present invention is not limited thereto, and can be applied to other types of resonators with a known load Q, such as cavity resonators and semi-coaxial resonators.

[0060]

As described in detail above, according to the automatic setting device for resonant frequency of a resonator according to claim 1 of the present invention,
an oscillation loop circuit that is equipped with an amplification means, is electrically connected to a resonator that has a predetermined load Q and is capable of changing a resonant frequency, and has a predetermined transmission phase; and an oscillation signal generated in the oscillation loop circuit. a frequency measuring means for measuring the oscillation frequency of the resonator; and a calculation for calculating the resonant frequency of the resonator based on the oscillation frequency measured by the frequency measuring means, the transmission phase of the oscillation loop circuit, and the load Q of the resonator. and control means for controlling the resonant frequency of the resonator so that the resonant frequency of the resonator becomes a preset frequency input based on the resonant frequency of the resonator calculated by the calculating means. Therefore, there is an advantage that the resonant frequency of the resonator can be automatically set to the set frequency with a simple configuration and with better accuracy than the conventional example.

Further, in the resonant frequency automatic setting type resonator according to claim 3 of the present invention, the resonator having a predetermined load Q and whose resonant frequency can be changed, and the resonator according to claim 1 or 2 are provided. This resonant frequency automatic setting type resonator is equipped with an automatic setting device and can automatically set the resonant frequency of the resonator to the set frequency with a simple configuration and with better accuracy than conventional examples. can be configured.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an automatic setting device for resonant frequency of a dielectric resonator, which is an embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view of the dielectric resonator of FIG. 1 and a shield case housing it.

3 is a vertical cross-sectional view showing details of the dielectric resonator of FIG. 1, a shield case housing the dielectric resonator, and a stepping motor drive mechanism.

FIG. 4 is a graph showing the relationship between the position of the dielectric tuning element of the dielectric resonator of FIG. 1 and the resonant frequency.

FIG. 5 is a flowchart showing automatic setting processing of the automatic setting device of FIG. 1;

6 is a longitudinal sectional view and a side view showing a first modification of the stepping motor drive mechanism of FIG. 1. FIG.

7 is a side view and a longitudinal sectional view showing a second modification of the stepping motor drive mechanism of FIG. 1. FIG.

8 is a side view and a longitudinal sectional view showing a third modification of the stepping motor drive mechanism of FIG. 1. FIG.

FIG. 9 is a block diagram of a conventional self-tuning resonator.

[Explanation of symbols]

10... Dielectric resonator, 11... Dielectric resonator, 12... Dielectric tuning element, 23, 24... Coil, 33... Amplifier, 34... Directional coupler, 35... Frequency counter, 40... Microprocessor unit (MPU) ), 42...
Keyboard, 51...Stepping motor, SW2...Switch.

Claims (3)

[Claims] 1. An oscillation loop circuit comprising an amplifying means, electrically connected to a resonator having a predetermined load Q and capable of changing a resonant frequency, and having a predetermined transmission phase; and the oscillation loop circuit. a frequency measuring means for measuring the oscillation frequency of an oscillation signal generated in the resonator; and a frequency measuring means for measuring the oscillation frequency of the oscillation signal generated in the resonator, based on the oscillation frequency measured by the frequency measuring means, the transmission phase of the oscillation loop circuit and the load Q of the resonator. a calculating means for calculating a frequency; and controlling the resonant frequency of the resonator so that the resonant frequency of the resonator becomes a preset frequency input based on the resonant frequency of the resonator calculated by the calculating means. 1. An automatic resonant frequency setting device for a resonator, comprising a control means. 2. The resonator includes a frequency variable element capable of changing an element constant that determines a resonant frequency, and the control means changes the element constant of the frequency variable element of the resonator. Based on the element constant changing means and the resonant frequency of the resonator calculated by the calculating means, the absolute value of the difference between the calculated resonant frequency of the resonator and the set frequency becomes less than a predetermined value. The element constant changing means is controlled to change the element constant of the frequency variable element of the resonator, thereby controlling the resonant frequency of the resonator so that the resonant frequency of the resonator becomes the set frequency. 2. The automatic setting device according to claim 1, further comprising frequency control means. 3. A resonant frequency automatic setting type resonator comprising a resonator having a predetermined load Q and capable of changing the resonant frequency, and the automatic setting device according to claim 1 or 2. vessel.