JP3521866B2 - Power distributor - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a power distributor,
In particular, it relates to a T-type power distributor used in a microwave monolithic integrated circuit (MMIC) or the like.

[0002]

2. Description of the Related Art A T-type power divider is used as a power divider that divides a microwave band input signal into two on a strip line.

In a conventional power divider of this type, as shown in FIG. 6, a branch point 8 connected to an input side strip line 1 having a characteristic impedance is connected to output side strip lines 2 and 3. The / 4 wavelength transformers 4 and 5 are connected to each other with the center line 6 of the input side stripline 1 as a boundary.

In the operation of this conventional power divider, the input signal in the microwave band incident from the input side strip line 1 and the input side strip line 1 and the transformer 4 of 1/4 wavelength,
At the connection portion with 5, the respective electric power is taken out to the output side strip lines 2 and 3 at a power distribution ratio according to the impedance ratio of the output side strip lines 2 and 3 viewed from the branch point 8. At this time, the microwave band input signal input to the input side stripline 1 is 1/4
Due to the function of the wavelength transformers 4 and 5, reflection is suppressed and distributed to the output side strip lines 2 and 3.

However, this conventional power distributor is
At the connection of the T-type distributor, a quarter-wave transformer 4,
Since the connection step 9 of 5 is set on the center line 6 of the input-side strip line 1, the connection step 9 disturbs the distribution of the electromagnetic field, so that it is viewed from the input-side strip line 1 at the operation center frequency of the input signal. Return loss is -15d
There is a problem that it is about B and is not sufficient.

[0006]

In the conventional power divider described above, the return loss seen from the input side strip line is caused by the disturbance of the distribution of the electromagnetic field at the connection portion of the T-type divider at the operating center frequency of the input signal. There is a drawback that is not enough.

An object of the present invention is to provide a power distributor with a small return loss by reducing the disturbance of the distribution of the electromagnetic field at the connection part of the T-type distributor in order to eliminate such conventional drawbacks. Especially.

[0008]

The power distributor of the present invention comprises:
A power divider that bifurcates an input signal in the microwave band, the first divider having an input-side strip line having a characteristic impedance and first and second output-side strip lines and being connected to face each other. And a second output-side strip line, via a first and second quarter-wave transformer having a line width according to the power distribution ratio, to a branch point on the center line of the input-side strip line. It is characterized by being connected respectively.

[0009]

The first and second quarter-wave transformers have different line widths depending on the split power distribution ratio, provided that they match the characteristic impedance of the input-side strip line. It is characterized by being set to.

Further, when the first and second quarter-wave transformers are respectively connected to branch points on the center line of the input side strip line, the connection step due to the different line widths is Within the range of the line width of the input side strip line from the center line, it is set to be displaced in either direction of the first and second output side strip lines.

Further, the first and second quarter transformer wavelength of, when connected respectively to the branch point of the center line of the input-side strip line, wherein the different connection by line widths step portion It is characterized by being configured so as to have a slope in the range of the line width of the input-side strip line.

Further, a strip conductor composed of a strip line and a transformer constituting the power distributor is formed on one surface of the dielectric substrate, and is composed of a double-sided substrate having the other surface as a ground conductor. There is.

Further, a strip conductor comprising a strip line and a transformer constituting the power distributor is a first ground conductor, a first dielectric substrate, the strip conductor, a second dielectric substrate, and a second dielectric substrate. It is characterized in that it is composed of a triplate substrate formed by stacking the ground conductors in this order.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of a power distributor of the present invention.

The present embodiment shown in FIG. 1 is a power divider that divides an input signal in the microwave band into two and has an input side strip line 1 and output side strip lines 2 and 3 having characteristic impedance. The output-side strip lines 2 and 3 connected in opposition to each other are connected to the center line of the input-side strip line 1 via the quarter-wave transformers 4 and 5 each having a line width corresponding to the power distribution ratio. 6 are connected to branch points 8 respectively.

When the quarter wavelength transformers 4 and 5 are connected to the branch point 8 on the center line 6 of the input-side strip line 1, a connection step 9 with a different line width is formed from the center line 6. Within the range of the line width of the input side strip line 1, it is set to be displaced in the direction of the output side strip line 3.

Next, the operation of the power distributor of this embodiment will be described in detail with reference to FIG.

In FIG. 1, the input-side strip line 1 and the output-side strip lines 2 and 3 form a line width having a characteristic impedance of 50 ohms on the dielectric substrate to be formed, and have a microwave width of the input microwave band. The signal is branched at the branch point 8 and power is transmitted to a circuit or the like having the same characteristic impedance, which is connected to the subsequent stage.

The quarter-wave transformers 4 and 5 are connected with the common center line 7 as a reference, and the impedance when the input-side strip line 1 to the output-side strip lines 2 and 3 are connected in parallel. , Input side strip line 1
The line width is determined so as to match the characteristic impedance of. The line widths of the two transformers 4 and 5 are set to different widths corresponding to the power distribution ratio.

FIG. 2 shows the return loss characteristic as the electrical characteristic of the power distributor of the present embodiment having the above-mentioned configuration.

In the example of FIG. 2, the quarter-wave transformer is
Connection steps 9 with different line widths are set to be shifted from the center line 6 of the input side strip line 1 to the output side strip line 2 side by approximately 90% of one side line width of the input side strip line 1.

As shown in FIG. 2, in this embodiment, as compared with the conventional example in which the connection step 9 of the quarter wavelength transformers 4 and 5 is set on the center line 6 of the input side strip line 1. 10d
It was obtained that the degree of improvement was about B. In this way, the input signal in the microwave band input to the input-side strip line 1 is on the center line 6 of the input-side strip line 1 and the connection step 9 due to the different line widths of the quarter-wave transformers. Is affected by the distribution of the electromagnetic field, and the effect is that the return loss characteristics cannot be obtained sufficiently.

As shown in FIG. 3, contrary to FIG. 1, the connection step 9 extends from the center line 6 of the input side strip line 1 to approximately 90% of one side line width of the input side strip line 1 on the output side strip. The same result as in FIG. 2 could be obtained also when the line was shifted to the side of the line 1.

Further, as shown in FIG. 4, also in the case where the connection step 9 is replaced and set so as to have an inclination 10 within the line width of the input side strip line 1,
The same result as in FIG. 2 was obtained.

As described above, the quarter wavelength transformers 2 and 3 are provided on the extension line of the input side strip line 1.
To reduce the disturbance of the distribution of the electromagnetic field on the extension line of the input side strip line 1 by shifting the connection step 9 due to the different line widths of the input side strip line 1 from the center line 6 of the input side strip line 1. As a result, the return loss can be improved.

The above embodiment is not limited to the T-type distributor composed of a double-sided board (not shown) whose one side is a ground conductor using a strip line, and, for example, as shown in FIG.
First layer ground conductor 52, second layer T-type distributor 51, third layer
It can also be applied to the triplate substrate 100 in which the ground conductors 53 of layers are sequentially stacked with the dielectric material sandwiched therebetween.

[0028]

As described above, according to the power distributor of the present invention, in the power distributor that splits the input signal in the microwave band into two, the line width is divided into four quarters according to the power distribution ratio. There is an effect that the return loss can be improved by shifting the connection step of the one-wavelength transformer from the center line of the input-side strip line or by giving an inclination to reduce the disturbance of the electromagnetic field distribution.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a power distributor of the present invention.

FIG. 2 is a diagram showing a return loss characteristic comparing a power distributor according to the present embodiment with a conventional example.

FIG. 3 is a configuration diagram showing another embodiment of the power distributor of the present invention.

FIG. 4 is a configuration diagram showing still another embodiment of the power distributor of the present invention.

FIG. 5 is a configuration diagram in which a triplate substrate is used in the power distributor of the present invention.

FIG. 6 is a configuration diagram showing an example of a conventional power distributor.

[Explanation of symbols]

1 Input side stripline A few output strip lines 4, 5 transformer 6, 7 center line 8 branch points 9 connection steps 10 tilt

Continuation of the front page (56) Reference JP-A-10-4305 (JP, A) JP-A-46-3618 (JP, A) JP-A-2002-76760 (JP, A) L. I. PARAD, et. al, S print-Tee Power Divider, IEEE Trans. Microwave Theory and Techniques, Jan. 1965, pp. 91-95 (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01P 5/12 H01P 5/02 603

Claims (5)

(57) [Claims] 1. A power divider that branches an input signal in the microwave band into two and has an input-side strip line having characteristic impedance and first and second output-side strip lines, and is connected to face each other. The first and second output-side strip lines that are formed are connected via first and second quarter-wave transformers having line widths according to the power distribution ratio,
When connected to the branch points on the center line of the input side strip line respectively , the line widths differ according to the power distribution ratio.
The connection step from the center line to the input side strip line
Within the width of the track, the first and second output side switches
A power distributor characterized by being set to be displaced in either direction of a trip line . 2. A power distributor for dividing an input signal in the microwave band into two, which has an input side strip line having characteristic impedance and first and second output side strip lines, and is connected to face each other. The first and second output-side strip lines that are formed are connected via first and second quarter-wave transformers having line widths according to the power distribution ratio,
When connected to the branch points on the center line of the input side strip line respectively , the line widths differ according to the power distribution ratio.
The connection stepped portion of the line width of the input side strip line is
A power distributor characterized by being set to have a slope within a range . 3. The first and second quarter-wave transformers have different line widths depending on the split power distribution ratio, provided that they match the characteristic impedance of the input-side strip line. The power distributor according to claim 1 or 2, wherein the power distributor is set to. 4. A strip conductor comprising a strip line and a transformer constituting the power distributor is formed on one surface of a dielectric substrate, and is composed of a double-sided substrate having the other surface as a ground conductor. The power distributor according to claim 1 or 2. 5. A strip conductor comprising a strip line and a transformer which constitute the power distributor comprises a first ground conductor, a first dielectric substrate, the strip conductor, a second dielectric substrate and a second dielectric substrate. 2. A triplate substrate formed by stacking ground conductors in this order.
Alternatively, the power distributor according to 2.