JPS5853767Y2 - power combiner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency power combiner for communication, and more particularly to a power combiner that combines three input powers.

Conventionally, this type of power combiner has a circuit as shown in Figures 1 and 2, with struts and limp lines formed on a printed circuit board, but this type of power combiner is designed to prevent wrap-around between input terminals. The resistors used for this purpose needed to be proportional to the combined power and had a large withstand power.

However, resistors with high power resistance need to have a heat dissipation effect, so the structure is such that the resistance element is placed between the ground plane and an insulating plate, and capacitance is formed between the resistance element and the ground plane, and high-frequency current However, there was a drawback in that this flowed into the ground plane through the resistive element, resulting in loss.

To explain Fig. 1, Fig. 1 is a Wilkinson type synthesizer, 1, 2.3 are input terminals, 4 is an output terminal, 8
, 9.10 is a resistor, and 18 is a quarter wavelength transmission line.

As is well known, the input and output impedance is Z.

Then, the characteristic impedance of the transmission line 18 is to the r row,
Resistor 8゜9.100 resistance value is Zo, input terminal 1
When only power is applied, resistor 9 has 4/9 of the input power.
, and resistors 8 and 10 each consume one-ninth of the input power.

Therefore, the resistor must be able to withstand that amount of power.

Also, power is applied to three input terminals, input terminals 1, 2 .
If the points 3 are at the same potential and phase, no current should flow through each resistor, but if the input power or phase of the three input terminals changes, current will flow through each resistor. Put it away.

Furthermore, as shown in FIG. 3, it is necessary to use a resistor with good heat dissipation as shown in FIG.

FIG. 4 is a side view of the resistor shown in FIG. 3.

This resistor includes a resistance element 23, an insulating plate 24, and a heat sink 25.
It has a structure that includes an input/output terminal 26, and the heat dissipation plate is grounded to a body or the like to improve heat dissipation.

For this reason, a capacitance is formed between the resistive element and the ground, and the higher the withstand power, the larger the area of the resistive element, and the larger the capacitance.

Also, Figure 2 shows a power combiner that first combines the power supplied to terminals 1 and 2, and then combines the power supplied to terminal 3. In the figure, 19,20°21.22 is τ Wavelength transmission lines 11, 19, and 12 are resistors.

The object of the present invention is to provide a power combiner that uses resistors with low power resistance and that improves the above-mentioned drawbacks.

According to the present invention, the power applied to the first input terminal 1 is distributed by a Wilkinson type distribution circuit, and then the power applied to the second and third input terminals 2 and 3 is combined with the Wilkinson type combining circuit. By further composing these using a Wilkinson-type synthesis circuit, it is possible to use a resistor with a power resistance that is approximately two-fifths that of the configuration shown in Figure 1 and one-half that of the configuration shown in Figure 2. A power combiner that has become possible is obtained.

Next, the present invention will be described in detail with reference to the drawings showing an embodiment of the present invention.

FIG. 5 is a diagram showing an embodiment of the present invention, in which power from input terminal 1 is divided into two, and the divided power is combined with power from terminals 2 and 3, respectively.

The respective combined powers are finally combined in the wavelength line 17 and output from the output terminal 4.

Here, 13, 14, 15°16 are τ wavelength lines, and 5
, 6.7 is a resistor.

Table 1 shows Figure 1 when the input/output impedance is zo,
The characteristic impedance of each transmission line and the resistance value of each resistor in FIGS. 2 and 5 are shown.

Next, Table 2 shows the power consumption per 2° of each resistor depending on the presence or absence of input from the three input terminals, assuming that each input power is 300W.

As explained above, in the present invention, by configuring as shown in FIG. 5, it is possible to use a resistor with low power resistance, and it is also possible to manufacture a combiner with low loss.

Table 2 shows that the circuit of the present invention allows the use of resistors with smaller power resistance.

[Brief explanation of drawings]

Figures 1 and 2 are diagrams showing conventional circuit diagrams, Figure 3 is a plan view of the resistor, Figure 4 is a side view of the resistor shown in Figure 3, and Figure 5 is a diagram of the resistor of the present invention. In the figure, 1, 2, 3...input terminals, 4...
...Output terminal, 5, 6, 7, 8, 9, 10, 11
. 12...Resistor, 13,14,15.16,1
7゜18.19,20...T wavelength line.

Claims (1)

[Claims for Utility Model Registration] A power combiner that combines three inputs; 1st (7)
Characteristic impedance ρjidingZ that receives input. A Wilkinson-type distribution circuit that includes two transmission lines (z: input/output impedance of the power combiner) and divides the first input into two; and a characteristic impedance C1 that receives the second input. and a characteristic impedance Z connected to the output end of the transmission line with characteristic impedance Z. a transmission line with a characteristic impedance 2Zo that receives one output from the distribution circuit, and a characteristic impedance Z. , 2Zo resistance value 2 inserted at the input end of the transmission line
zo resistance, and the characteristic impedance zo, 2Zo
a Wilkinson type first combining circuit that takes out a combined output from a connection point of the output end of the transmission line; a transmission line with a characteristic impedance of 0 to receive a third input; and the transmission line of characteristic impedance of 0 to 0; A transmission line with a characteristic impedance of 2° connected to the output end of the line, and a characteristic impedance 2 which receives the other output from the distribution circuit.
It includes a transmission line of Zo and a resistor of resistance value 2Zo inserted into the input end of the transmission line with characteristic impedance zo and 2zO, and outputs a composite output from the connection point of the output end of the transmission line with characteristic impedance zo and 2ZQ. A Wilkinson-type second synthesis circuit to be extracted: a characteristic impedance fΣZ receiving the outputs of the second and second synthesis circuits, respectively; two transmission lines and a characteristic impedance aZ. The resistance value 2z inserted at the input ends of the two transmission lines of
2 with a characteristic impedance hZo.
a Wilkinson-type third combining circuit that takes out a combined output from a connection point between output ends of two transmission lines, and takes out the combined power of the three inputs from the third combining circuit. vessel.