JPH0352021Y2 - - Google Patents

Description

[Detailed explanation of the invention] (Field of industrial application) The invention is a frequency converter using a distributed constant circuit used in receivers, etc. More specifically, the invention is a frequency converter using a distributed constant circuit and a rattrace circuit using a distributed constant circuit and two diodes. The present invention relates to a single-balanced frequency converter configured using a stub for high frequency removal using a distributed constant line.

(Prior Art) A frequency converter (hereinafter referred to as a mixer) using a distributed constant circuit is generally used as a circuit for converting a microwave band signal into an IF signal.

3 and 4 are circuit configuration diagrams showing the configuration of this conventional mixer. FIG. 3 is an example of a single balance type mixer, and FIG. 4 is an example of an image redirect type mixer.

In FIG. 3, 20 is a rat trace circuit, 6
is a stub for high frequency removal, 51 and 52 are diodes, 93 is a signal input terminal, 94 is a local signal input terminal, and 81 is a signal output terminal.A curved distributed constant circuit pattern is drawn on a substrate such as ceramic. ing. In addition, in FIG. 4, 27 and 28 are single-balanced mixers, 1 is a hybrid ring circuit, 3 is an in-phase hybrid circuit, and 71 and 72 are single-balanced mixers.
is a matching resistor, 100 is a connection line, 92 is a high frequency signal input terminal, 91 is a local signal input terminal, 81,
82 is an IF signal output terminal, and the above-mentioned single-balanced mixer, hybrid ring circuit, etc. are also drawn as a pattern of a distributed constant circuit on a substrate made of ceramic or the like.

(Problems to be solved by the invention) As is clear from the respective diagrams, each of the above mixers has a circular pattern created by a distributed constant circuit that constitutes a rattrace circuit or a hybrid ring circuit that uses lines that are an integer multiple of 1/4 wavelength. It is formed into a shape.

Since these mixers often use 1/4 wavelength lines, the size occupied by the mixer depends on the frequency used, and becomes larger as the frequency becomes lower. In particular, image-redirect mixers require a plurality of patterns, which occupies a large area on the substrate.

For example, when used at 1.5 GHz in the UHF band, even if ceramic with a relative dielectric constant of about 10 is used for miniaturization, the quarter wavelength of a microstripline distributed constant circuit will be about 2 cm. This requires a circular pattern with a diameter of about 4 cm in the form of a rattrace circuit, and similarly a circular pattern with a diameter of about 2.6 cm in the case of a hybrid ring circuit.
Therefore, as shown in Figure 4, an image redirect mixer requires a plurality of these, so approximately
A 10cm ² board is required.

For the above reasons, conventional mixers have been an obstacle to miniaturization of equipment, and also have disadvantages in that large ceramic substrates are easily broken, making them difficult to manufacture and increasing costs.

An object of the present invention is to provide a mixer that is smaller in size than conventional mixers and that solves the above-mentioned drawbacks.

(Means for Solving the Problems) To achieve the above object, a mixer according to the present invention has a rattrace circuit formed by a ring-shaped line, a stub formed by a rectangular line, and a frequency In the converter, the rat trace circuit is configured by sequentially connecting first to sixth lines each having a length of 1/4 wavelength, and the first line and the fourth line are straight and extend on both sides of the stub, respectively. The second line, the third line, the fifth line, and the sixth line are arranged parallel to each other along the long sides of the rectangle, and the intervals between their own lines and the intervals between each line due to bending are the same as the lines. The bent shape is equal to the width, and the distance between the stub and the first line and the distance between the fourth line are the average value of the line width of the rat trace circuit and the line width of the stub. and the two diodes are connected between the stub and the first line and the fourth line, respectively.

In the above configuration, the purpose of the stub is to remove unnecessary high frequency components, and low impedance is required for that purpose, so the line width is wide.
Additionally, a length of 1/4 wavelength is required. In the present invention, in order to reduce the overall size of the mixer, the stubs are brought close to each other to a distance that does not occur due to mutual influence between the lines. In addition, the distance between the second and third lines that are bent, the distance between the fifth and sixth lines, and the distance between the bent own lines must be set to a distance that does not cause any influence between the lines. It is made close to the same width as the line.

With such a configuration, the shape of the mixer can be minimized.

(Example) Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is an embodiment of a mixer according to the present invention, and is a circuit diagram of a single-balanced mixer. In the figure, the rattrace circuit 20, which has a length of 6/4 wavelength, has six 1/4 wavelength lines connected in sequence to form an annular shape. 21 of the first track
and the second line 24 have a straight line shape and are arranged parallel to each other. The second, third, fifth and sixth lines 22, 23, 25 and 26 are each bent as shown in the figure. The corners of the bending points of each of these lines 22, 23, 25, and 26 are cut at 45 degrees, so that the bending points do not have any influence. In addition, each of these lines 22, 2
The distance between the own lines and the distance between each line due to the bending of the lines 3, 25, and 26 are made equal to the line width, thereby preventing the lines from influencing each other. 1st and 4th
A stub 6 arranged parallel to these lines between the lines 21 and 24 has a wide line width to reduce impedance and remove unnecessary high frequencies.

The distance between the first line 21 and the stub 6 and the fourth
The distance between the line 24 and the stub 6 is set as an average value of the line width of the stub 6 and the line width of the first line 21 so that no influence occurs between the lines. In addition, in this figure, the bending shapes of the second, third, fifth, and sixth lines are shown as an example.

Rat trace circuit 20 arranged in this way
By connecting diodes 51 and 52 to the stub 6 and the stub 6 as shown in the figure, a single balanced mixer is constructed.

The high frequency signal is inputted from the input end 93, is switched by a local signal inputted from the input end 94, becomes an IF signal, and is outputted from the output end 81.

FIG. 2 shows an application example of the mixer according to the present invention, and is an example of an image-reject type mixer. Single balanced mixer 2 shown in Figure 1
7 and 28 so that their long sides are lined up,
An in-phase hybrid circuit 3 with a linear pattern is arranged between them. In addition, the long side of the hybrid ring circuit 1 in a rectangular pattern is arranged so that the short sides of the single balanced mixers 27 and 28 are adjacent to each other, and the input/output impedance of the circuit is
They are connected by a connecting line 100 with an impedance equal to Z ₀ . 4 is a substrate, and 71 and 72 are matching resistors. The signal input from the high frequency signal input terminal 92 is switched by the local signal input from the local signal input terminal 91, and the signal is switched between the two IFs.
The signals are output from signal output terminals 81 and 82 and combined externally. As is clear from a comparison with FIG. 4, by making the mixer according to the present invention a part of the configuration, it is possible to construct an image redirect mixer that is smaller than the conventional mixer.

(Effects of the invention) As explained in detail above, according to the invention, the area occupied by the mixer can be significantly reduced by changing the rattrace circuit, which is a component of the mixer, from the conventional circular shape. In particular, when an image-redirect mixer is configured, the area is approximately 1/4 that of the conventional mixer. This is particularly effective in the UHF band, where the circuit size is relatively large. By making the mixer smaller in this way, the high frequency section of the receiver or the like can be made significantly smaller. Further, since the mixer substrate can be small, the substrate is less likely to break, and manufacturing is easier, resulting in lower costs.

[Brief explanation of the drawing]

Figure 1 is a circuit configuration diagram showing an example of the frequency converter according to the present invention, which is an example of a single-balanced mixer, and Figure 2 is a circuit configuration diagram showing an application example of the frequency converter according to the present invention. 3 and 4 are circuit diagrams of conventional frequency converters, showing examples of a single-balanced mixer and an image-rejected mixer, respectively. 1...Hybrid ring circuit, 3...In-phase hybrid circuit, 4...Substrate, 6...Stub, 2
0...Rat trace circuit, 21-26...1/4 wavelength line, 27, 28...Single balance mixer, 51, 52...Diode, 71, 72...
Matching resistor, 81, 82...IF signal output terminal, 9
1... Local signal input terminal, 92... High frequency signal input terminal, 100... Connection line.

Claims (1)

[Scope of utility model registration request] In a frequency converter including a rattrace circuit formed by a ring-shaped line, a stub formed by a rectangular line, and two diodes, the rattrace circuit includes first to sixth diodes each having a length of 1/4 wavelength. The first line and the fourth line are linear and are arranged parallel to each other along the long sides of the rectangle on both sides of the stub, and the second line and the third line are arranged in parallel along the long sides of the rectangle. The line, the fifth line, and the sixth line are bent so that the interval between their own lines and the interval between each line is equal to the line width, and the interval between the stub and the first line and the interval between the lines are equal to the line width. The distance between the two diodes and the fourth line is an average value of the line width of the rat trace circuit and the line width of the stub. A frequency converter characterized in that the frequency converter is connected between the two.