JPH021443B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an oscillation multiplier that performs frequency multiplication using oscillation semiconductor elements such as impact diodes and Gunn diodes.

Prior Art and Problems Figure 1 is a diagram for explaining a conventional waveguide type oscillation multiplier, in which a is a front view and b is a -b-- of figure a.
A sectional view taken along line b is shown. In the figure, 1 and 2 are waveguides, 3 is an oscillation element, and 4 is a disk-type resonator, respectively. In this oscillation multiplier, the disk-type resonator 4 oscillates at a resonant frequency determined by the disk diameter and excites the waveguide 1. Therefore, by making the other waveguide 2 a cut-off waveguide, the waveguide 2 Now only harmonics are coming out. However, this oscillation multiplier has poor frequency stability and has the disadvantage of being very expensive, requiring it to be placed in a constant temperature bath or stabilized by injection locking. In addition, in an oscillation multiplier built into a microwave integrated circuit, the housing of the fundamental wave oscillation part acts as a three-dimensional circuit, and especially at ultra-high frequencies such as the millimeter wave band, there are many high-order mode resonances for harmonics. This resulted in large fluctuations in output, which hindered broadband characteristics.

Purpose of the Invention In view of the above-mentioned conventional drawbacks, the present invention separates the fundamental wave oscillation part having a dielectric resonator and the output waveguide part provided with an oscillation semiconductor element to prevent harmonic current from flowing into the part. The object of the present invention is to provide an oscillation multiplier that ensures stability of operation.

Structure of the Invention According to the present invention, an oscillation semiconductor element, a microstrip line having a dummy load, a dielectric resonator that resonates with the fundamental wave, and a cut-off waveguide that blocks frequencies higher than the output frequency are provided. In the oscillation multiplier, the semiconductor element for oscillation is installed in the output waveguide, and the fundamental wave oscillator and the fundamental wave oscillator are connected to each other by a microstrip line via a cut-off waveguide. This is achieved by providing an oscillation multiplier characterized in that it is connected.

Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram for explaining the oscillation multiplier according to the present invention, and a is a plan view with the lid removed;
b is a cross-sectional view taken along line bb in figure a.

In the figure, 10 is a metal casing, 11 is a cavity formed in the metal casing, 12 is a cut-off waveguide, 13 is an output waveguide, 14 is a two-terminal semiconductor for Gunn diode oscillation, and 15 is a ceramic substrate. ,
16 is a microstrip line, 17 is a dummy load, 18 is a first dielectric resonator, 19 is a sub-resonant circuit, 20 is a varactor, 21 is a diode bias terminal, 22 is a varactor bias terminal, 2
Reference numeral 3 indicates a second dielectric resonator, 24 a frequency adjustment screw of the second dielectric resonator, and 25 a metal lid.

As shown in FIG. 2, this embodiment includes a metal casing 10,
It consists of a microwave circuit housed in the metal casing and a metal lid 25 that closes the cavity of the metal casing. and an output waveguide 13 are formed. In the cavity 11, there is a fundamental wave oscillation section that includes a microstrip line 16, a dummy load 17, a first dielectric resonator 18, a sub-resonant circuit 19, a varactor 20, etc. formed or mounted on a ceramic substrate. A second dielectric resonator 23 is installed in the cut-off waveguide 12, and a two-terminal semiconductor 14 for oscillation such as a Gunn diode is installed in the output waveguide 13. It is connected to the microstrip line 16 of the fundamental wave oscillation section with a gold ribbon. The distance l 3 between this two-terminal semiconductor 14 for oscillation and the first dielectric resonator ₁₈ is approximately λ _g /4.
(2n−1) (where λ _g is the wavelength of the fundamental wave and n is an integer)
It is said that The metal lid 25 also has a frequency adjustment screw (not shown) for the first dielectric resonator 18 and a second
A frequency adjustment screw 24 of the dielectric resonator 23 is provided.

In this embodiment configured as described above, the distance between the two-terminal semiconductor 14 for oscillation and the first dielectric resonator 18 is set to approximately λ _g /4 (2n-1), so that the fundamental wave oscillation part waves are oscillated. The first dielectric resonator 18 is also coupled to a sub-resonant circuit 19, and can be frequency modulated by a varactor 20. In addition, the cut-off waveguide 12 prevents harmonics from leaking from the output waveguide 13 into the fundamental wave oscillation section through the microstrip line 16 with the second dielectric resonator 23, thereby reducing the influence of higher-order mode resonance. Excluding. In addition, the 2-terminal semiconductor 1 for oscillation
The distance l ₂ between the resonator 4 and the second dielectric resonator 23 acts as a matching element for the output frequency, so if l ₂ is made variable, the output can be adjusted.

Note that even when the second dielectric resonator 23 is not present, the first dielectric resonator 18 acts as a capacitive susceptance for the output frequency, and the first dielectric resonator 1
There are few harmonics flowing into the fundamental wave oscillation section in which No. 8 is accommodated, and even if a radio wave absorber is placed in the fundamental wave oscillation section to absorb higher-order mode resonance, the loss of output power is small, and it is sufficiently practical. There is an advantage that the second dielectric resonator 23 is not required.

FIG. 3 is a diagram for explaining another embodiment. This embodiment is different from the previous embodiment shown in FIG. 2, except for the second dielectric resonator 23 in the cut-off waveguide 12, and the microstrip line 16 is provided with stubs 26, 26'. This is a band-elimination device that blocks only the output frequency and cancels the fundamental wave. In this example, the second
Since output harmonics can be blocked even without a dielectric resonator, output power loss can be reduced and operation can be stabilized. Furthermore, since it can be constructed using microstrip lines, it has the advantage of being realized at a low cost.

Figure 4 shows a case where a three-terminal semiconductor such as a field effect transistor is used as an oscillation semiconductor element.
This figure shows an example, and by grounding the drain D, it appears as a negative resistance when viewed from the gate G, so it can be used in the same way as a diode.

Effects of the Invention As described above in detail, the oscillation multiplier according to the present invention has a two-terminal semiconductor for oscillation disposed within the output waveguide, and a microstrip line between the two-terminal semiconductor for oscillation and the dielectric resonator that performs fundamental wave oscillation. A cut-off waveguide is placed between the two to block the output frequency, and operation stability is ensured by blocking the harmonics that leak into the fundamental wave oscillator through the microstrip line. The effect is great.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining a conventional waveguide type oscillation multiplier, FIG. 2 is a diagram for explaining an oscillation multiplier according to the present invention, and FIGS. 3 and 4 are diagrams for explaining other embodiments. It is a figure for explaining. In the drawing, 10 is a metal case, 11 is a cavity, 12 is a cut-off waveguide, 13 is an output waveguide, 14 is a two-terminal semiconductor for oscillation, 16 is a microstrip line, 17 is a dummy load, and 18 is a third waveguide. 1 is a dielectric resonator, 23 is a second dielectric resonator, and 25 is a metal lid.

Claims (1)

[Claims] 1. An oscillation semiconductor element, a microstripline having a dummy load, a dielectric resonator that resonates with the fundamental wave, a cut-off waveguide that blocks frequencies above the output frequency, and a cut-off waveguide that blocks the fundamental wave. In the oscillation multiplier comprising an output waveguide, the oscillation semiconductor element is installed in the output waveguide and connected to the fundamental wave oscillation part by a microstrip line via a cut-off waveguide. oscillation multiplier. 2. The oscillation multiplier according to claim 1, wherein the cut-off waveguide is provided with a second dielectric resonator that resonates at the output frequency.