JPS5917707A - Frequency modulator controlled with dielectric resonator - Google Patents

Abstract

PURPOSE:To eliminate the mutual direct interference between a modulating part and an oscillating part and to prevent the generation of the excitation of the waveguide mode, by screening the modulating part, the oscillating part, etc. independently of one another. CONSTITUTION:The oscillating part and the modulating part are stored in respective cases 5 and 4 having a common wall 12, and the width of each cases 5 and 4 is made equal to or shorter than the half wavelength of the oscillation frequency. A notch is provided to a part of each of cases 5 and 4, and a dielectric resonator 1 is arranged so as to be coupled electromagnetically with an oscillation output line 2 and an induction line 3 through notches, and the resonator 1 is constituted so as to be covered with a resonator case 6 whose one side is equal to or shorter than the half wavelength of the oscillation frequency. Consequently, the direct coupling between the oscillating part and the modulating part and the excitation of the waveguide mode in cases 5 and 4 are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microphone n-wave frequency modulator, and more particularly to a frequency modulator controlled by a dielectric resonator.

Conventionally, this type of dielectric resonator controlled frequency modulator includes an oscillation output line connected to the output of an oscillation element that oscillates microwaves, a dielectric resonator electromagnetically coupled to the oscillation output line, and a dielectric resonator connected to the dielectric resonator. The electromagnetically coupled guide wires are arranged flat on the same substrate and housed in a common case to form the following structure.

The dielectric resonator is excited by passing a modulation signal onto the guide wire, and the oscillation frequency is modulated by coupling the modulation signal to the oscillation output line via the dielectric resonator. However, in the conventional modulator described above, the oscillation output line, the dielectric resonator, and the guide line are arranged in a plane, so the size of the case that accommodates them becomes large. As a result, a waveguide mode is excited within the case, which has the drawback of unexpectedly adversely affecting modulation linearity. Another disadvantage is that adjustment becomes difficult due to adverse effects such as mutual interference between the oscillation section and the modulation section.

An object of the present invention is to solve the above-mentioned conventional drawbacks and to
It is an object of the present invention to provide a dielectric resonator-controlled frequency modulator in which oscillation parts and the like are individually shielded to eliminate mutual direct interference and excitation of a waveguide mode does not occur.

The modulator of the present invention includes an oscillation output line connected to the output of a microwave oscillation element, a dielectric resonator electromagnetically coupled to the output line, and an inductive line electromagnetically coupled to the dielectric resonator. In the dielectric resonator controlled frequency modulator, the oscillation part case surrounds the oscillation output line and has a width and height of half a wavelength or less, and the width and height of the guide line surrounds the guide line. The following modulation unit cases are provided, and parts of both cases are arranged as a common wall or adjacent to each other, and the oscillation unit case and the modulation unit case can each be electromagnetically coupled to a part of the dielectric body. The dielectric resonator is arranged in a position where it can be electromagnetically coupled to the oscillation output line and the guide wire through the notch, and the dielectric resonator and the notch are on one side. It is characterized by being covered with a resonator case whose length is less than half a wavelength.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1(a) is a plan view showing an embodiment of the present invention, and FIG. 1(b) is a cross-sectional view taken along the line A-A'. That is, the oscillating unit case 5 and the modulating unit case 4 share the partition wall 12, and are formed to cover the upper and lower surfaces of the partition wall 12, respectively. A strip line 2 which is an oscillation output line is formed on an insulating layer of a predetermined thickness on the upper surface of the partition wall 120 in the figure, an oscillation element 7 is connected to one end of the strip line 2, and the other end passes through the case 5. and is connected to the output connector 8.

That is, the strip line 2 and the oscillation element 7 are surrounded by the case 5. The width and height of the case 50 are set to be less than a half wavelength of the oscillation frequency. On the other hand, a strip line 3, which is a guide wire, is formed on the lower surface of the partition wall 12 in the figure, and is surrounded by a case 4. Case 4 and case 5 share a partition wall 12. One end of the strip line 3 is open or short-circuited, and a varactor diode (not shown) is connected to the other end, and a modulation signal is applied from the outside via a choke coil or the like. A notch is provided at substantially the center in the longitudinal direction of the cases 4 and 5 on the same side (front side in the figure), and the dielectric resonator 1 is supported by a support base 11 on the front side thereof. Dielectric resonator IC; ↓, the strip lines 2 and 3 are magnetically coupled through the notch. The size of the notch is about % wavelength of the oscillation frequency. The notch and the dielectric resonator 1 are -
It is remembered that the resonator case 6 has a side length of less than a half wavelength of the oscillation frequency. The support base 11 is fixed to the inner wall of the case 6 and holds the resonator 1 in a predetermined position. In this embodiment, since the width, height, etc. of the cases 4, 5, and 6 are formed to be less than half a wavelength, the waveguide mode is not excited, and the strip lines 2 and 3 are not shielded by the partition wall 12. Therefore, there is no direct connection. The modulated signal sent to the stripline 3 is electromagnetically coupled to the resonator 1 through the notch in the case 4, and the resonator 1 is electromagnetically coupled to the stripline 2 through the notch in the case 5. be done. Therefore, a frequency modulation signal controlled to have an oscillation frequency corresponding to the modulation signal is outputted via the connector 8.

Note that the bias circuit 1 frequency adjustment mechanism of the dielectric resonator is the same as the conventional one, and although a description thereof will be omitted, since the above-mentioned various types of interference are prevented, the adjustment becomes easy.

FIG. 2(a) is a plan view showing another embodiment of the present invention, and FIG. A coaxial trap is formed, and the coaxial outer conductors 9 and 10 are arranged adjacent to each other vertically in the figure.In this case, the coaxial outer conductors 9 and 10 are
Each serves as an oscillation unit case and a modulation unit case. Both ends of the outer conductor 9 in the longitudinal direction are closed, the left end of the center conductor in the drawing projects outward and is connected to the connector 8, and the right end of the center conductor in the drawing is connected to the oscillation element 7.

A cutout is provided approximately in the center of the outer conductors 9 and 10 in the longitudinal direction, and the f'i9 electric resonator 1 is held on a support base 11 and placed in front of the cutout in the drawing. The shape of the dielectric resonator l is arbitrary, but it goes without saying that it is arranged in a convenient direction so that it can be electromagnetically coupled to both center conductors via the notch.

In this case, although the oscillating part case and the modulating part case do not have a common wall, it goes without saying that the same effect can be achieved by the same operation as in the above-described embodiment.

As described above, in the present invention, the oscillation section and the modulation section are housed in a case having a common wall, the width of each case is formed to be less than half a wavelength of the oscillation frequency range, and the width of each case is A notch is provided in a part of the resonator, and the dielectric resonator is arranged so as to be electromagnetically coupled to the oscillation output line and the guide line through the notch, and the length of one side is the oscillation frequency. Since the configuration is suitable for a resonator case of half a wavelength or less, there is an effect of preventing direct coupling between the oscillating section and the modulating section and preventing waveguide mode from being excited in each space. That is, an easily adjustable frequency modulator is provided that is free from adverse effects due to waveguide mode propagation and mutual interference between the oscillation section and the modulation section. Note that when the oscillation section and the modulation section are formed coaxially, the same effect can be achieved by using the coaxial outer conductors as the oscillation section case and the modulation section case and arranging both cases adjacent to each other.

[Brief explanation of the drawing]

FIG. 1(a) is a plan view showing one embodiment of the present invention;
b) is a sectional view taken along A-A', FIG. 2(a) is a plan view showing another embodiment of the present invention, and FIG. 2(b) is a sectional view taken along A-A'
FIG. In the figure, 1... dielectric resonator, 2.3... strip line, 4... modulation section case, 5... oscillation section case, 6... resonator case, 7... oscillation element , 8・
...Connector, 9, 10... Coaxial outer conductor, 11...
- Resonator support stand, 12... partition wall. Representative Patent Attorney Sumi 1) Toshi So Figure 1 (a) Figure 1 (b) 12C. Figure 2 (aI +A' 2152 Figure (1))

Claims (1)

[Claims] an oscillation output line connected to the output of the microwave oscillation element;
The dielectric resonator control frequency modulator includes a dielectric resonator that is electromagnetically coupled to the output line, and a modulation section that includes a four-wire conductor that is electromagnetically coupled to the dielectric resonator. An oscillating unit case surrounding the output line and having a width and height of less than half a wavelength is provided, and a modulating unit case surrounding the guide line and having a width and height of less than half a wavelength, and a part of both cases is used as a common wall. Alternatively, the oscillating unit case and the modulating unit case may each be provided with a notch that can be electromagnetically coupled to the electric body, and the dielectric resonator may be connected to the dielectric resonator through the notch. the dielectric resonator and the notch are covered with a resonator case having a side length of half a wavelength or less. Features of dielectric resonator controlled frequency modulator.