JPH01232801A - Power distributer - Google Patents

Abstract

PURPOSE:To facilitate the design of the distribution ratio, to attain stable quality and to reduce the cost by setting the width of a slit to form plural output parts dividedly from a tapered middle part to be wider in a range of not deteriorating the reflecting characteristic when viewed from the input part. CONSTITUTION:A microwave radiated from an input terminal P1 in a power distributer is outputted distributedly to output terminals P2-P5 by a distributing ratio in response to the input impedance of an output part 7. Moreover, the impedance matching between input and output terminals is taken by the tapered middle part 6. Through the constitution above, since the width of the end of the slit 8 at the input terminal side is selected to be as wide as possible in a range where the reflecting characteristic of the input terminal P1 is not deteriorated, that is, 1.5-3.5times the thickness of a dielectric base 2, the mutual effect of the output parts 7 is neglected and the effect of electric field concentration due to fringing at the side face of a strip conductor 3 is obtained similarly by the four output parts 7. Thus, the microwave is distributed equally regardless of the arrangement of the output parts 7 by making the width of the line of all the output parts 7 equal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power divider on a transmission line mainly used in microwaves.

[Prior art] Fig. 5 shows, for example, MrCROIIIAVE JOURNA.
L, NOVEMBER1986, PP, 147-151
1 is a configuration diagram showing a conventional power distributor shown in FIG. In the figure, 1 is a flat ground conductor, 2 is a dielectric substrate of approximately the same shape superimposed on the ground conductor 1, and 3 is a strip conductor provided on the dielectric substrate 2. A microstrip line 4 is constituted by the body substrate 2 and the strip conductor 3. The strip conductor 3 extends in a substantially triangular shape from one end of the dielectric substrate 2 to the other end,
An input section 5 having approximately the same width provided at one end of the dielectric substrate 2
A tapered middle part 6 which extends to the input part 5 and has a curved outline and is divided by three narrow slits 80 which extend to the middle part 6 and divide the middle part 6 into four parts. Four output parts 7 reaching the other end of the body board 2
The end surface side of the input section 5 becomes the microwave input terminal P1, and the end surface side of each output section 7 becomes the output terminal P1.
2 to P5. In addition, 9 is an isolation resistor, and it is inside each narrow slit 80 or each slit 80.
1 from the input terminal P1 side of each slit 80.
/4 wavelength position.

Next, the operation will be explained. Microwaves incident from the input terminal P1 pass through the microstrip line 4 and propagate radially through the tapered intermediate portion 6.

Further, the tapered intermediate portion 6 is divided into four parts by a narrow slit 80 cut halfway toward the output portion 7, and taken out to each of the output terminals P2 to P5.

At this time, microwaves are distributed and extracted to each of the output terminals P2 to P5 at a power ratio corresponding to the input impedance of each output terminal P2 to P5 as viewed from the input terminal Pl side of the tapered intermediate portion 6. The tapered intermediate part 6 has a characteristic impedance from the input terminal P1 side to the output terminals P2 to P5, and at the connection part with the output part 7, the impedance is equal to the impedance due to the parallel connection of the four output parts 7 at this connection part. Has characteristic impedance. In this way, in the above power distributor, impedance matching between the input and output terminals is achieved by the tapered intermediate portion 6, so that the microwave incident on the input terminal P1 is not reflected and is transmitted to each of the output terminals P2 to P41fi.
be taken care of. In addition, each output terminal P seen from the input terminal P1 side
The input impedance ratios of P2 to P5 are affected not only by the strip conductor width of each output section 7 but also by fringing on the side surface of the strip conductor 3. In the tapered intermediate portion 6, electric fields are concentrated on both sides due to the influence of fringing. On the other hand, each slit 80 provided from the tapered intermediate portion 6 to each output portion 7 is cut approximately radially from the input terminal P side, and the axial direction approximately coincides with the direction of the current.
Moreover, since the slit width is narrow, electric field concentration on the side surface of the strip conductor facing each slit 80 does not occur much. Therefore, when the tapered intermediate portion 6 is divided into equal widths by the slits 80, the output portions 7 on both ends are divided into the output portions 7 on the center side.
The impedance becomes lower, and the output terminals P2.
The power distributed to the central output terminals p3. It is larger than the power distributed to P. Therefore, input terminal P1
In order to equally distribute the microwaves incident on the output terminals P2 to P5, it is necessary to make the width of the output sections 7 on both ends narrower than the width of the output section 7 on the center side.

In addition, each output terminal P2 to P5 is connected to an isolation resistor 9.
Due to this function, a large return loss and mutual isolation between the output terminals are obtained. Each output terminal P2~
When microwaves with different amplitudes or phases are incident from P5, a potential difference is generated on both sides of the slit 80, and since the width of the slit 80 is narrow, the microwaves are outputted through the slit 80 even in a position where the isolation resistor 9 is not provided. This results in mutual coupling between the parts 7. Since the width of the slit 80 is narrow, the degree of coupling tends to vary due to slight differences in the slit width, requiring highly accurate processing.

[Problem to be solved by the invention] The conventional power divider is configured as described above, but
Because the width of the slit for dividing the output section from the tapered middle section is narrow, it is difficult to process the line with high precision, making it difficult to obtain stable quality, and the isolation characteristics between each output terminal are poor. In addition, in order to equally distribute microwaves to each output terminal, the width of the output section on both ends of each output section arranged in parallel should be narrower than the width of the other output sections. Therefore, there were problems such as difficulty in realizing an equal distributor with stable quality. In addition, there was a problem in that the cost was high due to the difficulty in designing and processing.

This invention was made to solve the above-mentioned problems, and it is easy to process the line, easy to design isolation between output terminals, and equally distribute microwaves with equal output width. It is easy to design the distribution ratio, and
The purpose is to obtain a power divider with stable quality at low cost.

[Means for Solving the Problems] In the power divider according to the present invention, the width of the slit for dividing and forming a plurality of output parts from the tapered intermediate part is set within a range where the reflection characteristics seen from the input part side are not deteriorated. This is a wide range of settings.

[Function] This invention focuses on the phenomenon that the electric field concentrates on the side surfaces of the strip conductor, resulting in low impedance due to the influence of fringing on the side surfaces of the strip conductor, and the reflection characteristics of the width of the slit when viewed from the input section side are degraded. By widening the line to the extent that it does not, processing of the line becomes easier and coupling between the output parts becomes smaller. In addition, if the widths of each output section are made equal, the input impedance of each output section as seen from the input section side will be the same regardless of the placement position of the output section, and the microwaves incident from the input terminal can be easily distributed equally. Designing the distribution ratio becomes easier,
Low cost and stable quality can be obtained.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram showing an embodiment using microstrip lines, and in the figure, 1 to 7, 9, P1 to P,
5 is the same as or equivalent to the conventional example shown in FIG. 5, and 8 is a wide slit according to the present invention for dividing and forming four output portions 7 from the tapered intermediate portion 6. The strip conductor 3 in this embodiment extends in a substantially triangular shape from one end of the dielectric substrate 2 to the other end, and connects to an input portion 5 of the same width provided at one end of the dielectric substrate 2. The input section 5 is connected to a tapered intermediate section 6 whose contour line is widened in a straight line and whose tip is an arc, and the intermediate section 6 is divided into four equal widths by three wide slits 8 from the distal end side. It is integrally constituted by four output parts 7 that extend radially with the same width from the center and reach the other end of the dielectric substrate 2. Therefore, the width of each slit 8 is narrowest at the end on the input terminal P1 side, but the width is made as wide as possible within the range described later without degrading the reflection characteristics at the input terminal P1. Further, the isolation resistor 9 is provided in the same slit 8 at a position 1/4 wavelength away from the input terminal P1 side end of each slit toward the output terminal side.

Next, the operation will be explained. In this power divider, as in the conventional example, the input terminal P! The microwaves incident thereon are distributed and outputted to the output terminals P2 to P5 at a distribution ratio according to the input impedance of the four output sections 7. Further, impedance matching between the input and output terminals is also achieved by the tapered intermediate portion 6 as in the conventional example.

By the way, when microwaves are incident from the input terminal P, the microwaves propagating through the adjacent output sections 7 have equal amplitude and equal phase within the cross section of the output section 7, so the electric field distribution is as shown in Fig. 2. It becomes like this. As shown in FIG. 2(a), when the intervals between the output parts 7 are narrow, that is, the narrow slits 80
In the conventional device, each output section 7 influences each other, so that electric field concentration on the side surface of the strip conductor 3 due to fringing hardly occurs. On the other hand, Fig. 2(b)
As shown in FIG. 2, when the distance between the output sections 7 is increased due to the wide slit 8 of the present application, the influence of each output section 7 on each other is reduced, and the electric field is concentrated on the side surface of the strip conductor 3, so that each output section 7 is Similarly, the impedance is low. Therefore, even if the width of the slit 8 is increased to the extent that the influence of each output section 7 on each other cannot be ignored, the electric field will be concentrated on the side surface of the strip conductor 3 by the increased width, and each output section 7 will have a low impedance. The characteristic impedance of the four output sections 7 connected in parallel does not change, and the reflection characteristics of the input terminal Pl hardly deteriorate. The maximum value of the slit width at which the overall characteristic impedance of the output section 7 does not change varies depending on the width of the strip conductor 3, but in the case of a microstrip line, this maximum value ranges from 1.5 to 1.5 of the thickness of the dielectric substrate 2. It is about 3.5 times.

In the power divider of this embodiment, the width of the input terminal side end of the slit 8 is set to a value as wide as possible without deteriorating the reflection characteristics of the input terminal P1, that is, 1.5 times the thickness of the dielectric substrate 2.
Since it is set to ~3.5 times, the influence of the output parts 7 on each other can be ignored, and the effect of electric field concentration due to fringing on the side surface of the strip conductor 3 can be similarly obtained in the four output parts 7.

Therefore, if the line widths of all the output sections 7 are made equal, the microwaves will be equally distributed regardless of the arrangement position of the output sections 7.

In addition, each output terminal P2 to P5 is connected to an isolation resistor 9.
Through this function, return loss and mutual isolation between the output terminals are obtained. In this power distributor, since the width of the slit 8 is wide, when microwaves are incident from the output terminal, the coupling between the output parts 7 through the slit 8 at a position other than the position where the isolation resistor 9 is provided can be ignored. Compared to the conventional example, it is easier to design considering the isolation between the output sections 7.

FIG. 3 is a block diagram of a power distributor according to another embodiment of the present invention, in which a dielectric plate 10 is stacked and closely attached to a strip conductor 3 having the same shape as that in FIG. A tri-plate line 40 is constructed by bonding the ground conductor 1a to the ground conductor 1a. The ground conductors 1 and 1a, the dielectric substrate 2, and the dielectric plate 10 arranged from above and below have substantially the same shape, and are stacked one on top of the other with the strip conductor 3 in between.

FIG. 4 is a block diagram showing still another embodiment of the present invention, in which strips of the same shape as the embodiment of FIG. Conductor 3a
and 3b are glued together to create a suspended strip line 40.
It constitutes 0.

These strip conductors 3a and 3b have substantially the same shape and are bonded to the dielectric substrate 2 so as to overlap each other, and the strip conductors 3a and 3b are separated from the inner wall of the ground conductor 1.

The width of the end of the slit 8 on the input terminal Pl side in the embodiments shown in FIGS. 3 and 4 is also made as wide as possible without degrading the reflection characteristics of the input terminal Pl. It is approximately 0.4 to 0.5 times the interval.

The embodiments shown in FIGS. 3 and 4 have the same operating principles and effects as the embodiment shown in FIG. 1.

In the above embodiment, the case of a 4-divider was explained, but a 2-3 distribution, or 5 or more distribution may be used, and the same effects as in the above embodiment can be obtained.

Furthermore, although the above-mentioned embodiment shows an example in which the isolation resistor 9 is provided, if isolation between output terminals is not required, the present invention may be applied to a case where no isolation resistor is provided.

Further, in the above embodiment, the case where the outline of the tapered intermediate portion 6 is a straight line has been described, but the invention can also be applied to a case where the outline is a curved line.

[Effects of the Invention] As described above, according to the present invention, the width of the slit for dividing and forming a plurality of output parts from the tapered intermediate part can be increased within a range that does not deteriorate the reflection characteristics seen from the input part side. This setting makes it easier to process the line, and allows you to design isolation between output terminals while ignoring the coupling between output terminals, resulting in equal distribution with equal output section width, making it easier to design the distribution ratio. There is an effect that a stable power divider with small variations in quality can be obtained at low cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a power divider according to an embodiment of the present invention, FIGS. 2(a) and (b) are diagrams showing the operating principle of the embodiment of FIG. 1, and FIG. FIG. 4 is a partially-missed block diagram showing a power divider according to another embodiment of the invention; FIG. 5 is a partially-missed block diagram showing a power divider according to still another embodiment of the invention; 1 is a configuration diagram showing a conventional power divider. 1.1a is a ground conductor, 2 is a dielectric substrate, and 3.3a. 3b is a strip conductor, 4 is a microstrip line,
40 is a triplate line, 400 is a suspension isolation resistor, 10 is a dielectric plate, Pl is an input terminal, Pz~P
5 is an output terminal. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] A ground conductor and a strip conductor are provided through a dielectric substrate, and the strip conductor is connected to an input portion provided at one end of the dielectric substrate, a tapered intermediate portion extending from the input portion and widening, and a tapered intermediate portion extending from the input portion to the intermediate portion. In a power divider consisting of a plurality of output sections that are continuous and divided by slits and reach the other end of the dielectric substrate, the width of the slits is set to be wide enough that the reflection characteristics seen from the input section side do not deteriorate. A power divider characterized by: