JP2000059114A - Frequency adjusting device for nrd guide millimeter wave band oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To vary the resonator length of a ceramic resonator without varying ceramic thickness and to finely adjust a frequency with high precision by providing a mechanism which varies the resonator length nearby the ceramic resonator which is installed so that it is coupled with an NRD guide. SOLUTION: A screw 39 penetrating upper and lower conductor plates 37 and 38 is provided nearby the ceramic resonator 32 and rotated to vary the interval between the uppers and lower conductor plates 37 and 38, so that the oscillation frequency is controlled with precision of several KHz. Namely, the ceramic resonator 32 is constituted by sandwiching a ceramic disk 32a of a hard dielectric with high Q vertically between 'TEFLONR' disks 32b and 32c of soft dielectrics with a low dielectric constant. Therefore, frequency variation is large due to variation in the thickness, but variation in the thickness of the disk 32a is small since it is hard. The disks 32b and 32c have small frequency variation with the thickness and large thickness variation. Consequently, the oscillation frequency can be adjusted to a desired frequency with precision of several KHz through the rotation of the screw 39.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frequency adjusting device for an NRD-guided millimeter-wave band oscillator constituting an upconverter, a radar device, or a digital transceiver for communication between computers.

[0002]

2. Description of the Related Art Utilization of millimeter wave radio waves in the 35 GHz band, 60 GHz band, and the like has been studied, and its practical use has attracted attention.
It is known that an NRD guide formed by inserting a rectangular dielectric strip into a cut-off parallel plate waveguide is advantageous as a transmission line of a millimeter wave band such as a 35 GHz band and a 60 GHz band. As shown in FIG. 7, the NRD guide is made of aluminum arranged in parallel at predetermined intervals above and below,
A rectangular rod-shaped dielectric strip 63 having a height a and a width b is placed between an upper conductor plate 61 and a lower conductor plate 62 having a thickness of about 4.0 mm and made of a good conductor or non-magnetic material such as copper or brass. Arranged and configured. As the dielectric strip 63, a high-frequency and low-loss specific dielectric constant such as a millimeter-wave band is 3.0 or less, for example, 2.04 Teflon, 2.1 polyethylene, 2.5
Assuming that a free space wavelength of a signal frequency is λ ₀ , a dielectric strip line 6 is used.
Height a of 3, near the width b of a = 0.45λ ₀ is the dielectric constant When epsilon _r,

[0003]

(Equation 1)

[0004] is set. In the 60 GHz band, when Teflon is used as the dielectric strip, the height a =
2.25 mm, width b = 2.5 mm, 55 GH
A single mode operating band is obtained from z at 65.5 GHz.

A millimeter-wave band oscillator applied to such an NRD guide is described in, for example, “60 GHz using NRD guide.
z-band FM gun oscillator ”IEICE Transactions on Communications (C-
I), Vol. J77-CI, No. 11, pp59
2-598 (November 1994). As shown in FIG. 8, the millimeter-wave band oscillator is an NRD constructed by inserting a rectangular dielectric strip into a cut-off parallel plate waveguide.
Using a guide, 60 GHz is obtained with an InP gun diode or a GaAs gun diode. As shown in FIG. 8B, the Gunn diode 64 is screwed and fixed inside a brass metal piece 65 that has been subjected to a λ / 4 step low-pass filter in order to suppress leakage of millimeter waves.
It is loaded horizontally between 6,67. Gun diode 6
As shown in FIG. 8C, a bias voltage to 4 is applied through a λ / 4 microstrip low-pass filter 69 formed by etching on a Teflon substrate 68 having a thickness of 0.13 mm adhered on the metal piece 65. Is done. The oscillation output from the Gunn diode 64 is guided to an NRD guide 73 via a metal strip resonator 72 in which a metal strip 71 is formed on a Teflon substrate 70, as shown in FIG. The oscillation frequency of the metal strip resonator 72 can be determined by the width c and length d of the metal strip 71 and the thickness e of the Teflon substrate 69. In this document, the thickness e of the Teflon substrate 70 is 0.265 mm, the width c of the metal strip 71 is 1.4 mm, and the length d is 1.5 mm.
From 2.5GHz to 63mm
Hz, and almost covers the band of the NRD guide in the 60 GHz band, and the oscillation output is 130 mW or more.

[0006] Also, "Self-injection Gunn Oscillator Using Non-radiative Dielectric Line", Transactions of the Institute of Electronics, Information and Communication Engineers (C-
I), Vol. J72-CI, No. 1, pp532
-58 (January 1989) is a gun diode 75 screwed to a metal piece 74 as shown in FIG.
The oscillation output from N is supplied to N through a metal strip resonator 76.
In a millimeter-wave band oscillator that leads to a dielectric strip 77 constituting an RD guide, a dielectric disk resonator 78 is installed near the dielectric strip 77 in a band-rejected manner and a part of the output is injected back. Dielectric disk resonator 7
8 discloses a structure of a self-injection gun oscillator that synchronizes a Gunn diode oscillator. Dielectric disk resonator 7
Reference numeral 8 denotes a ceramic having a diameter of 3.5 mm and a relative dielectric constant of 24.5 sandwiched between polyfoam or Teflon having a relative dielectric constant of 1.03 from above and below, and the thickness of the ceramic, the dielectric strip 77 and the dielectric disk resonance. G and z of the vessel 78
A method of controlling the oscillation output and the oscillation frequency by changing the direction position is disclosed.

Japanese Unexamined Patent Publications Nos. 6-177649 and 6-177650 disclose an exploded perspective view in FIG. 10A, a plan view of a printed circuit board in FIG.
As shown in the plan view of the mounted state in (c), the gun diode 81 mounted on the metal piece 80 is exposed to the front side of the printed board 82 through the through hole 83 of the printed board 82,
A first bias supply line 84 having a Gunn diode 81 formed on the surface of a printed circuit board 82 and a rectangular metal pattern 85
And an NRD guide millimeter-wave oscillator in which a varactor diode 88 is connected between the rectangular metal pattern 85 and the second bias supply line 86. The frequency of the NRD guide millimeter-wave band oscillator is roughly adjusted from 57.5 GHz to 61.8 GHz by the vertical and horizontal dimensions f and h of the rectangular metal pattern 85, and between the Gunn diode oscillator and the dielectric strip 86 constituting the NRD guide. It is described that the fine adjustment is performed by the metal strip resonator 87 installed.

[0008]

Since the above-mentioned NRD guide millimeter wave oscillator oscillates in a free-running state, the oscillation frequency drifts due to ambient temperature, applied voltage, and the like. In order to improve this, the gun oscillator of FIG. 9 has a dielectric disk resonator 78 composed of high-Q ceramics side-coupled near a dielectric strip 77 constituting an NRD guide. The oscillation frequency during self-running is
± 0.5% of the resonance frequency of the ceramic constituting
In the case of a slight deviation, the oscillation output is pulled into the resonance frequency of the ceramic, and the oscillation output returns to the Gunn diode 75 with the phase noise removed. Due to this self-injection effect, the Gunn diode oscillator oscillates stably in synchronization with the resonance frequency of the ceramic.

Therefore, when adjusting the oscillation frequency of the Gunn diode oscillator, the gap g between the dielectric strip 77 and the dielectric disk resonator 78 and the shape of the ceramic may be changed. And desired characteristics were obtained. However, as shown in FIG. 11 (horizontal axis is the thickness t of the ceramic, vertical axis is the frequency), the thickness t of the ceramic changes only by 10 μm at most, and the frequency changes by 400 MHz as shown in FIG. And is in a very critical relationship, several KH
It was difficult to control the resonance frequency with the accuracy of z.

Japanese Patent Application Laid-Open Nos. Hei 6-177649 and Hei 6-177650 disclose that coarse adjustment is performed by using the vertical and horizontal dimensions f and h of the rectangular metal pattern 85 and fine adjustment is performed by using the metal strip line 87. I have.

However, the above-described metal strip line 71
Of adjusting the frequency according to the width c, length d and the thickness e of the Teflon substrate 72, the method of changing the distance g between the dielectric strip 77 and the dielectric disk resonator 78, and the method of adjusting the ceramic thickness t The method of changing the frequency by the vertical and horizontal dimensions f and h of the rectangular metal pattern 85 and the metal strip resonator 87 can be determined through trial manufacture and experiment in the design stage of the Gunn diode oscillator, but it is adjusted after the product is assembled. It is not a possible means.

An object of the present invention is to provide a frequency adjusting device for an NRD-guided millimeter-wave band oscillator which can solve the above-mentioned problems.

[0013]

According to a first aspect of the present invention, there is provided a frequency adjusting device for an NRD guide millimeter wave band oscillator, comprising a millimeter wave oscillator and an oscillating signal supplied from the millimeter wave oscillator. Guide comprising a dielectric strip inserted between conductive plates, and a ceramic resonator installed to be side-coupled to the NRD guide
A frequency adjusting device for a guide millimeter wave band oscillator, comprising a mechanism for changing a resonator length of the ceramic resonator near the ceramic resonator. By having this feature, the present invention can change the resonator length of the ceramic resonator without changing the thickness of the ceramic after assembling the millimeter wave oscillator, and fine-tune the frequency with high accuracy. Can be.

According to a second aspect of the present invention, in the frequency adjusting apparatus for an NRD-guided millimeter-wave band oscillator, the mechanism for changing the resonator length of the ceramic resonator comprises a mechanism for changing the interval between the conductor plates. It is characterized by. According to this feature, the resonance length of the ceramic resonator resonates at a frequency at which the distance between the conductor plates is an integral multiple of a half wavelength, so that the oscillation frequency can be adjusted.

According to a third aspect of the present invention, in the frequency adjusting apparatus for an NRD-guided millimeter-wave band oscillator, the mechanism for changing the interval between the conductor plates comprises a screw penetrating the conductor plates. . With this feature, the oscillation frequency can be adjusted by turning the screw with a screwdriver while looking at the monitor, and the oscillation frequency can be finely and accurately adjusted to a desired frequency. The screw is installed near the ceramic resonator, and changes the distance between the upper and lower conductor plates near the ceramic resonator, and thus can effectively adjust the oscillation frequency of the millimeter wave oscillator.

According to a fourth aspect of the present invention, there is provided a frequency adjusting apparatus for an NRD guide millimeter-wave band oscillator, wherein a ceramic resonator is relatively hard and a dielectric material having a high dielectric constant is in the middle, and the upper and lower portions are relatively soft and low. It is characterized by a structure sandwiched between dielectric materials having a dielectric constant. Due to this feature, even when the distance between the conductor plates is changed, the thickness of the dielectric material having a relatively low dielectric constant changes mostly, and the thickness of the dielectric material having a relatively high dielectric constant changes only slightly. do not do. Therefore, the change rate of the resonance frequency of the ceramic resonator is small,
The oscillation frequency can be controlled with an accuracy of several KHz.

A frequency adjusting device for an NRD guide millimeter wave band oscillator according to claim 5 of the present invention is provided in an NRD guide transmitter and an NRD guide receiver for up-converting a CS television signal and a BS television signal, respectively. It is characterized by. With this feature, NRD guide transmitter and NR
The difference in oscillation frequency between the NRD guide millimeter wave band oscillators incorporated in each D guide receiver can be suppressed to ± 1 MHz or less, and the signal can be reliably reproduced.

[0018]

(Embodiment) FIG. 1 shows an NR of the present invention.
FIG. 1 is a block diagram of a transceiver that uses a frequency adjusting device of a D-guide millimeter-wave band oscillator in an NRD-guided multi-channel television signal transmission system. A BS analog television broadcast wave 1 and a CS digital television broadcast wave 2 transmitted from satellite broadcasting are received by a BS antenna 3 and a CS antenna 4, respectively. The BS television broadcast wave is frequency-converted to 1.035 to 1.335 GHz on all 15 channels,
TV broadcast waves use vertical polarization and horizontal polarization, and use 7 channels per polarization, for a total of 14 channels, 1.293 to 1.54.
The frequency is converted to 8 GHz and input to the block converter 5. The block converter 5 converts the vertical polarization into 1.385 to 1.625 GHz and the horizontal polarization into 1.655 to 1.895 GHz so that the vertical and horizontal polarizations of the CS television signal can be mixed with the BS television signal. 1.035 to 1.895G for BS and CS television signals
Rearranged into one IF signal of Hz. This IF signal is I
The signal is supplied from the F signal output terminal 7 to the NRD guide transmitter 6.

The NRD guide transmitter 6 has an oscillation frequency of 5
Oscillation signals from the Gunn diode oscillator 8 set in the 9 GHz band are transmitted to the NRD guide circulators 9, 10.
, And is input to the up-converter 11 composed of a Schottky barrier diode. The up-converter 11 includes the Gunn diode oscillator 8
Is mixed with the IF signal input from the block converter 5 to up-convert the IF signal into a 60 GHz band signal. The frequency-converted signal passes through the band-pass filter 12 and is a sum signal of 60 GHz.
Only the band signal is transmitted to the transmitting antenna 13. The 58 GHz band signal, which is the difference signal, is reflected without passing through the band-pass filter 12, and is reflected by the NRD guide circulators 9, 1 and 2.
It is guided by 0 to the non-reflective end 14, where it is absorbed.

60 GH transmitted from the transmitting antenna 13
The z charged wave is received by the receiving antenna 1 of the NRD guide receiver 15.
6 and input to the balance mixer 18 via the NRD guide directional coupler 17. The 59 GHz band oscillating signal from the Gunn diode oscillator 19 is applied to the balance mixer 18 to perform down-conversion, convert it to the original IF signal, and output it. The IF signal is divided by the divider 20 into a BS television signal and a CS television signal, and input to the CS tuner 21 and the BS tuner 22. After the BS television signal passes through the BS tuner 22, it is divided into a HDTV and a general BS television signal by the divider 2.
3, each of which has a television receiver 24,
25 and 26, and the video is reproduced. Where CS
Since the input signal frequency bands of the tuner and the BS tuner are set in accordance with the frequency arrangement of the block converter used on the transmission side, an NRD guide transmitter and an NRD guide receiver are required to reliably reproduce the signal. Must be equal to or less than ± 1 MHz. In addition,
It is also possible to add a VHF / UHF band terrestrial television broadcast signal to the embodiment of FIG. 1 and simultaneously upconvert and transmit the signal. In this case, the IF signal of the terrestrial television broadcast signal is preferably rearranged in the 2 GHz band which is a higher frequency side than the BS television signal and the CS television signal.

The specific structure of the NRD guide transmitter 6 is configured as shown in a plan view shown in FIG. 2A and a three-dimensional view shown in FIG. 2B, and the same parts as those in FIG. It is shown as follows. The Gunn diode 28 is mounted on the side surface of the metal piece 27 having an H-shaped cross-section by being enclosed in a cylindrical ceramic package and applying a bias voltage thereto via a microstrip line having a λ / 4 choke pattern. A 60 GHz band oscillation signal is obtained from the Gunn diode oscillator 8. This oscillation signal is guided to the NRD guide 31 via the metal strip resonator 29. Here, it is desirable to insert a mode suppressor 31a at the tip of the NRD guide 31 in contact with the metal strip resonator 29 in order to suppress unnecessary modes generated at the coupling portion. The metal strip resonator 29 has a desired frequency of 5
It is adjusted to the 9 GHz band. In this embodiment, 58.36G
Hz or 59.15 GHz.

A ceramic resonator 32 having a high Q for frequency stabilization is arranged near the NRD guide 31 so as to be side-coupled, and the ceramic resonator 32 operates with the direction of the interval between the upper and lower conductor plates as the resonator length. To stabilize the frequency. The ceramic resonator 32 has a high Q ceramic disk 32a in the middle and is vertically sandwiched between Teflon disks 32b and 32c. The ceramic disk 32a is located at the center of the upper and lower conductor plates to eliminate radiation. The resonance frequency of the ceramic disk 32a can be increased by reducing the thickness t, thereby shortening the resonator length. When the thickness is set to 0.47 mm, the resonance frequency becomes 59 GHz. This ceramic resonator 32 has NR
The distance g from the D guide 31 was set to 1.35 mm, and the standing wave ratio was set to 2.

The oscillation signal input to the NRD guide 31 is guided by the NRD guide circulators 9 and 10 toward the up-converter 11 and input. NRD guides 33 and 34 are inserted between the NRD guide circulators 9 and 10 and between the NRD guide circulator 10 and the up-converter 11, respectively, and connect between them.
When the oscillation signal output is set to 13 mW, 11 dBm is input to the up converter 11.

The up-converter 11 receives the BS television signal and the CS television signal from the terminal 30 in a range of 1.035 to 1.0.
An IF signal rearranged to 895 GHz is input, and the frequency is converted here. A terrestrial television broadcast signal rearranged in the 2 GHz band may be added to the IF signal. The frequency-converted sum signal and difference signal pass through the NRD guide circulator 10 and the NRD guide 35 to the band-pass filter 12. Bandpass filter 12
Has a center frequency of 60.625 GHz, a bandwidth of 2 GHz,
It consists of a 0.5 dB ripple three-stage Chebyshev filter, passes only the sum signal, and transmits it to the transmitting antenna 13. When the output of the sum signal and the difference signal of the up-converter 11 is 0 dBm, the output of the sum signal at the output of the band-pass filter 12 is 0 dBm. The difference signal that cannot pass through the band-pass filter 12 is reflected, guided by the NRD guide circulators 9 and 10 to the non-reflection end 14 via the NRD guide 36, and absorbed.

The specific structure of the NRD guide receiver 15 is as follows.
It is configured as shown in the plan view of FIG. 3A and the three-dimensional view of FIG. 3B, and the same parts as those in FIG. 1 are denoted by the same reference numerals.
The 60 GHz charged wave received by the receiving antenna 16 is NR
3 dB NR constituted by curved D guides 41 and 45
It is divided into two through the D guide directional coupler 17.
The radius of curvature and the angle of curvature are r = 10 m by the NRD guide 41.
m, θ = 110 degrees, and the NRD guide 45 is r = 43 mm. The NRD guide 45 can be formed by a straight line. 60 GHz charged wave is NRD guide directional coupler 1
After being divided into two by 7, the balance mixer 18a,
18b. The balance mixers 18a and 18b have a structure in which detection is performed by the two Schottky barrier diodes 18c and 18d, thereby increasing the detection sensitivity. Teflon chips 18e and 18f are attached to the front surfaces of the mounts of the Schottky barrier diodes 18c and 18d to protect the Schottky barrier diodes 18c and 18d from being broken. Schottky barrier diode 18
A high-dielectric-constant thin film is attached on the back of the mounts c and 18d, and the Schottky barrier diode 18 having a small resistance
c, 18d, NRD guide 4 with high impedance
1, 45. The thickness of the high dielectric constant thin film is λ / 4. Further, Teflon chips 18g and 18h are attached after the high dielectric constant thin film to further improve the matching with the NRD guide.

59 GH from Gunn diode oscillator 19
The z oscillation signal is applied to the balance mixer 18 through the NRD guide directional coupler 17 by the NRD guide 45,
Then, it is down-converted and the original IF signal is
Get 2

In this NRD guide receiver 15,
The Gunn diode oscillator 19 has a Gunn diode mounted on a metal piece 43, similarly to the Gunn diode oscillator 8 of the NRD guide transmitter 6, and an oscillation signal from the Gunn diode oscillator 19 passes through a metal strip resonator 44 to the NRD.
Guided by guide 45. It is preferable to insert a mode suppressor 46 at the tip of the NRD guide in order to suppress an unnecessary mode generated at a coupling portion with the metal strip resonator 44. Similar to the ceramic resonator 32 of the NRD guide transmitter 6, a ceramic resonator 47 for frequency stabilization is arranged near the NRD guide 45 so as to be side-coupled. The frequency is stabilized by operating with the direction as the resonator length. The ceramic resonator 47 is constituted by sandwiching a high-Q ceramic disk in the middle with a Teflon disk on the upper and lower sides, so that the ceramic disk is located in the middle of the upper and lower conductor plates to eliminate radiation. The ceramic disk has a thickness t of 0.47 mm and a resonance frequency of 59 mm.
GHz. The distance between the ceramic resonator 47 and the NRD guide 45 was set to 1.35 mm, and the standing wave ratio was set to 2.

The ceramic resonator 32 provided in the NRD guide transmitter 6 and the ceramic resonator 47 provided in the NRD guide receiver 15 can use alumina or the like as a substitute for a ceramic disk, and as a substitute for a Teflon disk. Polyethylene, polystyrene,
Boron nitride or the like can be used. The shape can be an ellipse, a triangle, or a square other than a circle, but a circle is easiest to manufacture. Further, the ceramic resonator may have a structure in which one of the upper and lower sides is supported by a Teflon disk so that the ceramic disk is in the middle of the upper and lower conductor plates, and the other is a space. In this case, the ceramic disk preferably has a dielectric constant close to infinity.

The Gunn diode oscillator 8 of the NRD guide transmitter 6 and the Gunn diode oscillator 19 of the NRD guide receiver 15 have the same structure as described above, and are close to the NRD guide for frequency stabilization. A ceramic resonator is provided. Here, the Gunn diode oscillator 8 of the NRD guide transmitter 6 will be described.
9 is also applied. FIG. 4 is a three-dimensional view showing the vicinity of the Gunn diode oscillator 8, the NRD guide 31, and the ceramic resonator 32 of the NRD guide transmitter 6, and FIG.
2 is a sectional view taken along line AA ′ of FIG. Gunn diode oscillator 8
Is composed of a self-injection-locked NRD gun oscillator whose oscillation frequency can be varied and controlled with an accuracy of several KHz.

As described above, the ceramic resonator 32 is composed of a relatively hard dielectric ceramic disk 32a having a high Q and a Teflon disk 32b, which is a soft dielectric having a lower dielectric constant than the ceramic at the top and bottom.
The ceramic disk 32a is located at the center of the upper and lower conductor plates so as to be sandwiched by 2c. The ceramic resonator 32 is formed in a circular shape, and its periphery is covered with a ring-shaped Teflon tube 32d made of a dielectric having a low dielectric constant. The Teflon tube 32d prevents the ceramic resonator 32 from losing its shape, and at the same time, prevents the influence of humidity due to dew condensation and the like inside the NRD guide transmitter and the NRD guide receiver. The resonance frequency of the ceramic resonator 32 is determined by the interval between the upper and lower conductor plates including the direction of the interval between the upper and lower conductor plates including the thickness t as the resonator length, and the frequency at which this interval is electrically an integral multiple of half a wavelength. Resonates at Since the ceramic resonator 32 resonates at _TE20δ , the ceramic disk 32a can be thinned to increase the resonance frequency. While adjusting the overall height of the ceramic resonator 32 to 2.25 mm between the upper and lower conductor plates, the resonance frequency is adjusted by thinning the ceramic disk 32a and thickening the Teflon disks 32b and 32c. Ceramic disk 32a
Is 0.47 mm thick to obtain a resonance frequency in the 59 GHz band.

The ceramic resonator 32 has the NRD guide 3
The distance g between 1 and the ceramic resonator 32 is determined at a position where the standing wave ratio becomes 2. At this time, g was 1.35 mm. In addition, the distance z from the mode suppressor end face of the NRD guide 31 to the center of the ceramic resonator 32 was set at a position where the ceramic resonator 32 rocks. The locking positions were 6.0 mm and 6.5 mm as shown in FIG. At the time of locking, even if the frequency axis (SPAN) of the spectrum analyzer was set to 50 kHz, no change in the oscillation frequency was observed and the waveform was beautiful.

The upper conductor plate 3 is located near the ceramic resonator 32.
7. A screw 39 penetrating the lower conductor plate 38 is provided. The screw is provided at a position where the resonance electromagnetic field is so small as to be negligible. The electromagnetic field distribution in the radial direction of the ceramic resonator is attenuated by a change in e- ^pr , where r [m] is the coordinate in the radial direction, and p [Np / m] is the lateral attenuation constant analyzed by the electromagnetic field theory. Therefore, in general, the distance r is set such that the attenuation of the electromagnetic field in the radial direction of the ceramic resonator satisfies 8.686 pr ≧ 30 dB. In this embodiment, the screw 3 is placed on a line passing through the ceramic resonator 32 in the vertical direction from the NRD guide 31.
9 are arranged. It is desirable to provide a nut outside the lower conductor plate 38 to increase the tightening. When the screw 39 is rotated by a driver or the like, the distance between the upper conductor plate 37 and the lower conductor plate 38 near the ceramic resonator 32 changes, and the oscillation frequency can be controlled with an accuracy of several KHz. That is, when the distance between the upper and lower conductor plates is changed, the resonator length of the ceramic resonator 32 is changed, but the frequency change with respect to the thickness of the ceramic disk 32a is greatly changed due to a high relative dielectric constant. On the other hand, in the Teflon disks 32b and 32c, the relative dielectric constant is low, and the resonance electromagnetic field is exponentially attenuated inside the ceramic disk 32a. Therefore, even if the thickness changes, the change in the resonator frequency is small. . Further, the ceramic disk 32a is relatively hard, and the Teflon disk 32
Since b and 32c are relatively soft, the Teflon disk 3
The thicknesses of the ceramic disks 32b and 32c change greatly, while those of the ceramic disk 32a hardly change. Therefore,
Turn the screw while looking at the monitor to increase the oscillation frequency by several K
It can be adjusted to a desired frequency with an accuracy of Hz.
After the adjustment, stop the screw rotation so that the frequency does not change unnecessarily. As a result, the NRD guide transmitter 6 and the NR
The IF frequency difference of the D guide receiver 15 can be set to several KHz, and the signal can be reliably reproduced.

The shape of the screw can be variously modified. In short, any structure can be used as long as the distance between the upper and lower conductor plates can be adjusted, and various structures such as a lever, a gear and the like can be used. It is desirable that a mechanism for adjusting the interval between the upper and lower conductor plates is provided not only on one side of the ceramic resonator 32 but also on both sides thereof so as to change the thickness of the ceramic resonator evenly.

Although the above embodiment has been described with reference to an up-converter, the present invention is not limited to this, and a POS terminal communication system, a train millimeter wave communication, The present invention can be applied to a frequency adjusting device of an NRD guide millimeter wave band oscillator that constitutes a millimeter wave ID system, a traffic information beacon, a wireless camera (FPU), and the like.

[0035]

As described above, according to the present invention,
After assembling the millimeter-wave oscillator, the resonator length of the ceramic resonator can be changed, and the frequency can be finely adjusted with high accuracy by changing the thickness of the Teflon disk. Further, according to the present invention, resonance occurs at a frequency at which the distance between the conductor plates is an integral multiple of a half wavelength, so that the oscillation frequency can be adjusted. Further, according to the present invention, the oscillation frequency can be adjusted by turning the screw with a screwdriver while looking at the monitor, and the oscillation frequency can be finely and precisely adjusted to a desired frequency. The screw is installed near the ceramic resonator, and changes the distance between the upper and lower conductor plates near the ceramic resonator, and thus can effectively adjust the oscillation frequency of the millimeter wave oscillator. Further, according to the present invention, when the distance between the conductor plates is changed, the thickness of the dielectric having a low dielectric constant changes mostly, and the thickness of the ceramic is slight. Therefore, the change in the resonance frequency of the ceramic resonator is small, and the oscillation frequency can be controlled with an accuracy of several KHz. Also according to the invention, the NRD guide transmitter and N
IF of NRD guide millimeter wave band oscillator of RD guide receiver
The frequency difference between the signals can be reduced to about ± 1 MHz, and the signals can be reliably reproduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a transceiver when the present invention is applied to an NRD guide multi-channel TV signal transmission system.

FIG. 2 is a configuration diagram of an NRD guide transmitter.

FIG. 3 is a configuration diagram of an NRD guide receiver.

FIG. 4 is a partial perspective view of a frequency adjusting device of an NRD guide millimeter wave band oscillator.

FIG. 5 is a sectional view taken along line A-A ′ of FIG. 4;

FIG. 6 is a characteristic diagram of frequency and output when the position z of the ceramic resonator is changed.

FIG. 7 is a configuration diagram illustrating an NRD guide.

FIG. 8 is an explanatory diagram of a configuration of a frequency adjusting device of an NRD guide millimeter wave band oscillator.

FIG. 9 is a structural diagram of a frequency adjusting device of a conventional NRD guide millimeter wave band oscillator.

FIG. 10 is a configuration explanatory diagram of another conventional frequency adjusting device for an NRD guide millimeter wave band oscillator.

FIG. 11 is a diagram showing the relationship between the thickness of a ceramic disk and the frequency.

[Explanation of symbols]

 31, 33, 34, 35, 36 NRD guide 32 Ceramic resonator 32a Ceramic disk 32b, 32c Teflon disk 32d Teflon tube 37, 38 Conductor plate 39 Screw

Claims (5)

[Claims] A millimeter-wave oscillator; an NRD guide to which an oscillation signal is supplied from the millimeter-wave oscillator; a dielectric strip inserted between conductor plates arranged in parallel;
What is claimed is: 1. A frequency adjusting device for an NRD-guided millimeter-wave band oscillator comprising a ceramic resonator disposed to be coupled to a guide, comprising a mechanism for changing a resonator length of the ceramic resonator near the ceramic resonator. A frequency adjusting device for an NRD guide millimeter wave band oscillator. 2. The frequency adjustment of the NRD guide millimeter-wave oscillator according to claim 1, wherein the mechanism for changing the resonator length of the ceramic resonator comprises a mechanism for changing the interval between the conductor plates. apparatus. 3. A mechanism for changing an interval between the conductor plates,
3. The frequency adjusting device for an NRD guide millimeter wave band oscillator according to claim 2, comprising a screw penetrating the conductor plate. 4. The ceramic resonator according to claim 1, wherein said ceramic resonator has a structure in which a relatively hard dielectric material having a high dielectric constant is placed in the middle and a dielectric material having a relatively soft upper and lower dielectric constant is sandwiched therebetween. 2. The frequency adjusting device of the NRD guide millimeter wave band oscillator according to 1. 5. The NRD guide millimeter-wave oscillator frequency adjusting device according to claim 1, provided in an NRD guide transmitter and an NRD guide receiver for up-converting a CS television signal and a BS television signal, respectively. Frequency adjusting device for NRD guide millimeter wave band oscillator.