JPS6360607A - Two-band microwave receiver - Google Patents

Abstract

PURPOSE:To receive a two-band microwave signal through a waveguide by connecting a 1st rectangular waveguide having a 1st width and 2nd rectangular waveguide having a 2nd width to the post-stage of a horn via a tapered matching circuit sequentially. CONSTITUTION:A rectangular waveguide 2 is connected to the post-stage of a circular/rectangular conversion waveguide 1. The rectangular width l1 of the waveguide 2 has a size through which a two-band low frequency microwave is able to pass. Then the waveguide 2 is connected to a rectangular waveguide 4 via a tapered matching circuit 3. The width l2 of the rectangular waveguide 4 has a size through which a two-band high frequency band is able to pass. Thus, microwaves of high and low frequency bands are extracted separately from both the waveguides 2, 4 respectively. Thus, a two-band microwave signal is received through one waveguide.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a two-band microwave receiving device capable of receiving microwave signals of two bands with one waveguide.

(Prior art) For example, in satellite broadcasting in the United States, 3.7 to 4.2 GH
Television broadcasting and the like are performed using microwave bands such as the C band of Z and the Ku band of 11.7 to 12.2 GHz.

These microwave signals are reflected and focused on, for example, a parabolic surface, and are received by a receiving device disposed at the focal point of the parabolic surface.

Here, a device for receiving two-band microwave signals such as C-band and Ku-band consists of a waveguide 1 for receiving a C-band microwave signal and a K-band microwave signal as shown in FIG.
A waveguide 2 for receiving a U-band microwave signal is arranged close to the focal point of a parabolic surface 3.

(Problems to be Solved by the Invention) The conventional two-band microwave receiving device described above requires waveguides 1 and 2 for each of the C band and Ku band. There was a problem that the device as a whole was expensive. Furthermore, since the two waveguides 1.2 are placed near the focal point of the parabolic surface 3, both must be placed slightly away from the focal point, which makes it difficult to efficiently input microwave signals. Can not. Furthermore, since the two waveguides 1.2 are disposed close to each other, there is a problem in that the design of the horn for matching the incident waves is restricted.

An object of the present invention was to solve the problems of the conventional two-band microwave receiving device described above, and to make it possible to receive two-band microwave signals with one waveguide. An object of the present invention is to provide a two-band microwave receiving device that has the following characteristics.

(Means for Solving the Problem) In order to achieve the above object, the two-band microwave receiving device of the present invention includes a first rectangular guide having a first width at the rear stage of the horn into which the microwave signal is incident. A second rectangular waveguide having a second width narrower than the first width is connected to the rear stage of the first rectangular waveguide through a matching circuit whose width becomes narrower in a tapered manner. Then, the microwave signal in the low frequency band is extracted from the first rectangular waveguide, and the microwave signal is extracted from the second rectangular waveguide.
It is configured to extract microwave signals in high frequency bands from the rectangular waveguide.

(Function) A first rectangular waveguide with a first width and a second rectangular waveguide are installed after the horn.
A second rectangular waveguide with a width of Furthermore, microwaves having a higher predetermined frequency or higher can pass through the second rectangular waveguide with a second width. By extracting microwave signals in a lower frequency band than the first rectangular waveguide and extracting microwave signals in a higher frequency band than the second rectangular waveguide, one waveguide can generate two bands. Each microwave signal can be extracted separately.

(Description of Embodiments) Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 1 is a partially cutaway external perspective view of an embodiment of the two-band microwave receiving device of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. FIG. 2 is a perspective view of the two-band microwave receiving device shown in the figure placed at the focal point of a parabolic surface.

In FIGS. 1 and 2, a circular rectangular conversion waveguide 1 is provided as a horn into which a microwave signal is incident, and a first rectangular waveguide having a first width is provided downstream of the circular rectangular conversion waveguide 1. A wave tube 2 is connected by a flange. The rectangle at the rear end of the circular-rectangular conversion waveguide 1 and the rectangle at the tip of the first rectangular waveguide 2 match, and the first width 21 is the same as the rectangle at the rear end of the circular-rectangular conversion waveguide 1. The dimensions are set so that microwaves in the lower frequency band (C band) can pass through. Furthermore, a matching circuit 3 is formed at the rear end of the first rectangular waveguide 2 to smoothly convert from the first width 11 to a narrower second width 12 in a tapered shape. A second rectangular waveguide 4 having a second width is flange-connected to the rear end of this matching circuit 3. The rectangle of this second rectangular waveguide 4 and the matching circuit 3? & The end rectangles match, and their second width 12 is the 2 that you are trying to receive.
The dimensions are set to be able to block the passage of the lower frequency band (C band) and to allow the passage of the higher frequency band (KU band).

Note that the heights of the first rectangular waveguide 2 and the second rectangular waveguide 4 are both approximately 22/2. In the first rectangular waveguide 2, a first pickup probe 5 is arranged perpendicularly at the center position in front of the matching circuit 3 by a length of 1/4 wavelength of the center frequency of the low frequency band. . Also,
A shorting plate 6 is disposed at the end of the rectangular waveguide 4 of i2, and a second pickup probe is installed perpendicularly to the central position in front of the shorting plate 6 by a length of 1/4 wavelength of the center frequency of the high frequency band. 7 are arranged.

The two-band microwave receiving device configured in this way is
As shown in FIG. 3, it is placed at the focal point of the parabolic surface 8.

Next, the operation of the two-band microwave receiving device will be explained. Only one waveguide is required, and it is placed at the focal point of the parabolic surface 8, so that the microwave signal is efficiently incident on the circular-rectangular conversion waveguide 1 as a horn. The first rectangular waveguide 2 functions as a bypass filter whose cutoff frequency is determined by the first width ILl, and allows microwaves in a low frequency band to be received and microwaves in a higher frequency band to pass therethrough. . Further, the second rectangular waveguide 4 functions as a bypass filter whose cutoff frequency is determined by the second width IL2, and allows microwaves in a high frequency band to be received and microwaves in a higher frequency band to pass therethrough. . Here, the matching circuit 3 of the first rectangular waveguide 2
functions as a short circuit plate that blocks the passage of microwaves in the low frequency band, and the first pickup probe 5, which is disposed at a position 1νf by a length of 1/4 wavelength from this short circuit plate, detects the low frequency band. A microwave signal is extracted. In addition, from the shorting plate 6 to the second rectangular waveguide 4,
A microwave signal in a high frequency band is extracted by a second pickup probe 7 placed in front by a length of four wavelengths.

Therefore, one waveguide can separately receive two bands of microwave signals, such as the C band and the U band, which have widely different frequencies. The microwave signals extracted by the first and second pickup probes 5.7 in this manner are converted into lower frequency signals by a low-noise frequency converter (not shown) and supplied to the subsequent circuit.

FIG. 4 is an external perspective view of another embodiment of the two-band microwave receiving device of the present invention. In FIG. 4, the same members as those in FIG. 1 are given the same reference numerals and redundant explanations will be omitted.

In FIG. 4, the difference from FIG. 1 is that the microwave signal in the low frequency band is extracted from the branch waveguide 8, which is E-branched from the first rectangular waveguide 2, and the microwave signal is extracted from the second rectangular waveguide. The rear end of the tube 2 is open, and a microwave signal in a high frequency band is extracted. These microwave signals are then converted into lower frequency signals by a frequency converter (not shown) and supplied to a subsequent circuit.

(Effects of the Invention) As explained above, according to the two-band microwave receiving device of the present invention, microwave signals of two bands can be separately extracted using one waveguide, which is different from the conventional one. The entire device can be constructed at a lower cost than other devices that require waveguides for each band. Moreover, since there is only one waveguide, the waveguide can be placed accurately at the focal point of the parabolic surface, and the microwave signal can be efficiently input, which is an excellent effect.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway external perspective view of an embodiment of the two-band microwave receiving device of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. FIG. 4 is a perspective view of the two-band microwave receiving device of FIG. 1 arranged at the focal point of a parabolic surface; FIG. The figure is an overall perspective view of a conventional two-band microwave receiving device. DESCRIPTION OF SYMBOLS 1: Circular-rectangular conversion waveguide, 2: First rectangular waveguide, 3: Matching circuit, 4: Second rectangular waveguide, 5: First pickup probe, 6: Shorting plate, 7: First 2 pickup probe.

Claims (2)

[Claims] (1) A first rectangular waveguide with a first width is connected to the rear of the horn into which the microwave signal is incident, and the width is tapered to become narrower after the first rectangular waveguide. A second rectangular waveguide having a second width narrower than the first width is connected through a circuit, a microwave signal in a low frequency band is extracted from the first rectangular waveguide, and a microwave signal in a low frequency band is extracted from the first rectangular waveguide. A two-band microwave receiving device characterized in that it is configured to extract a microwave signal in a high frequency band from a rectangular waveguide. (2) A first pickup probe is disposed perpendicularly in the center position of the first rectangular waveguide in front of the length of 1/4 wavelength of the center frequency of the low frequency band from the matching circuit. Extract the microwave signal of the frequency band,
A shorting plate is provided at the end of the second rectangular waveguide, and this second
A second pickup probe is disposed vertically at a central position in front of the short-circuit plate by a length of 1/4 wavelength of the center frequency of the high frequency band in the rectangular waveguide to detect the microwave signal of the high frequency band. 2. The two-band microwave receiving device according to claim 1, wherein the two-band microwave receiving device is configured to take out the following.