JPH0680974B2 - Series power supply circuit - Google Patents

Description

TECHNICAL FIELD The present invention relates to a series feeding circuit which is one of feeding circuits for an array antenna.

[Conventional technology]

FIG. 3 shows a conventional series feeding circuit described on pages 222 to 224 of, for example, “Antenna Engineering Handbook” (published by The Institute of Electronics, Information and Communication Engineers, Ohmsha, Ltd.).
19 is a coupler, 31 to 38 are lines, 50 is a matching terminator, Po is an input / output terminal, P1 to P9 are distribution output terminals, and the couplers 11 to 19 are connected in series through the lines 31 to 38. There is.

In the series feeding circuit configured as described above, the electric waves incident on the terminal P0 are sequentially coupled to the couplers 11-
A necessary amount of electric power is taken out by the terminals 19 to the terminals P1 to P9, and the remaining electric power is absorbed by the matching terminator 50. At this time, the terminal
The phase distribution of the waves extracted to P1 to P9 is determined by the electrical length of the lines 31 to 38.

For example, if the electric lengths of the lines 31 to 38 are selected to be equal, the terminals P1 to
The phase difference between adjacent terminals of P9 is expressed by the following equation.

However, φ _{1 to} φ ₉ = phase of the wave extracted to terminals P1 to P9 λg = wavelength of lines 31 to 38 Lo = line length of lines 31 to 38 As can be seen from this formula, the wave extracted to terminals P1 to P9 Has a phase distribution with equal intervals and different phases.

Further, since the wavelength λg changes depending on the frequency and the phase difference between adjacent terminals also changes, it can be used as a power feeding circuit such as a frequency scanning antenna.

[Problems to be solved by the invention]

However, in the conventional series power feeding circuit, the couplers 11 to 19 are connected in cascade, so that the reflected waves from the couplers are superimposed.

For example, the reflection coefficient Γ of the series feeding circuit shown in FIG. 3 is expressed by the following equation when multiple reflection is ignored.

Here, Γ _{1 to} Γ ₉ : Reflection coefficient of couplers 11 to 19 C _{1 to} C ₉ : Coupling degree of couplers 11 to 19 (dB) For simplicity, C ₁ = C ₂ = ... = C ₈ = When _{C 9 = -9.5dB ... (3)} Γ 1 = Γ 2 = ...... = Γ 8 = Γ 9 = Γo ... (4) that becomes Γ = 5.9Γo ... (5). This value becomes larger as the number of distribution output terminals increases and the number of couplers increases.

Therefore, the conventional series power supply circuit has a problem that VSWR is significantly deteriorated when the number of distribution output terminals is large.

The present invention has been made to solve the above problems, and an object thereof is to obtain a series power supply circuit having a good VSWR with a relatively simple configuration.

[Means for solving problems]

The series feeding circuit according to the present invention is configured to alternately connect the couplers and the first lines in cascade, and obtain a distributed output from each coupler, or from each coupler and the line at the final end. A plurality of first series feeding circuits, a coupler, and a second
And a second series feed circuit configured to obtain a distributed output from each coupler and the line at the final end, and a plurality of distributed outputs of the second series feed circuit. Each of the terminals is connected to an input terminal of each of the plurality of first series feeding circuits, and the second of the second series feeding circuits is connected.
The line length of the line is equal to or longer than the total line length of the first line in the corresponding first series feeding circuit, and the input terminal of the second series feeding circuit is The input terminals of the entire circuit are used, and the distribution output terminals of the plurality of first series feeding circuits are used as the distribution output terminals of the entire circuit.

[Action]

In the present invention, each of the plurality of distribution outputs distributed by the second series power feeding circuit is individually distributed by each of the plurality of first series power feeding circuits and output to the outside. Becomes Therefore, the reflected waves in the plurality of first series feeding circuits on the output side are not superposed, and the couplers and the lines are simply cascaded alternately to obtain a plurality of distributed outputs of 4 or more. It is possible to reduce the reflection coefficient in the entire circuit as compared with the above circuit.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 to 3 are first series feeding circuits, 4 is second series feeding circuits, 11 to 21 are couplers, and 31 to 36. Is the first line, 37 and 38 are the second lines, 51 to 53 are matching terminators, P0 is the input terminal, and P1 to
P9 is a distribution output terminal of the first series power feeding circuits 1 to 3, P10 to P
12 is a distribution output terminal of the second series power feeding circuit 4, and P 13 is an input terminal of the coupler 21.

Thus, in the series power feeding circuit of this embodiment, the couplers 11 to 13 are
Is the first lines 31 and 32, the couplers 14 to 16 are the first lines 33 and 34,
The couplers 17 to 19 are connected in series via the first lines 35 and 36 to form first series feeding circuits 1 to 3 each having three distribution output terminals.

The couplers 20 and 21 are connected in cascade via a second line 37 having a line length three times as long as that of the first line, and a second line 38 is connected to this.
To form the second series feeding circuit 4.

Further, the input terminals of the first series power feeding circuits 1 to 3 are connected to the distribution output terminals P10 to P12 of the second series power feeding circuit 4, respectively. Then, the input terminal P0 of the second series power feeding circuit 4 becomes the input terminal of the entire circuit, and the distribution output terminals P1 to P3, P4 to P6, P7 to P8 of the first series power feeding circuits 1 to 3 respectively.
Serves as the distribution output terminal of the entire circuit. With the above configuration, a series power supply circuit having nine distributed output terminals, similar to the conventional series power supply circuit shown in FIG. 3, is configured.

Next, the function and effect of this embodiment will be described.

In the series feed circuit configured as described above, the wave incident on the terminal P0 is first provided with the required amount of power by the couplers 20 and 21 while being propagated through the lines 37 and 38 of the second series feed circuit 4. The electric power remaining at the terminals P10 and P11 is taken out at the terminal P12. The waves extracted to the terminals P10 to P12 are similarly power-distributed by the first series feeding circuits 1 to 3 and finally distributed to the terminals P1 to P9. At this time, the phase distribution of the waves extracted at the terminals P1 to P9 is determined by the electrical length of the lines 31 to 38.

For example, the track length of tracks 31 to 36 is Lo, and the track length of tracks 37 and 38 is
If it is 3Lo, the phase difference between the adjacent terminals of the terminals P1 to P9 is the same as that of the conventional series feeding circuit, and is represented by the first equation. Therefore, the series feeding circuit according to this embodiment can also be used as a feeding circuit for a frequency scanning antenna or the like, like the conventional series feeding circuit.

Then a reflection coefficient of the series feed circuit of the present embodiment but, for simplicity of explanation, the degree of coupling C ₁ -C ₁₁ and the reflection coefficient gamma ₁ to? ₁₁ of the coupler 11 to 21 conventional series feed As in the case of the circuit, the value of the following equation is used.

_{C 1 = C 2 = ...... =} C 11 = -9.5dB ... (6) Γ 1 = Γ 2 = ...... = Γ 11 = Γo ... (7) At this time, the reflection of the first series feed circuit 1-3 Coefficient Γ a ₁ ,
Γa ₂ and Γa ₃ have the following values.

Γa ₁ = Γa ₂ = Γa ₃ = 2.7Γo (8) In the coupler 21, the reflected waves of the series feed circuits 2 and 3 are coupled in phase with the terminal P13, and the reflected wave from the coupler 21 is also superimposed in phase. Then, the reflection coefficient Γb ₁ at the terminal P13 becomes the value of the following equation.

Similarly, the reflection coefficient Γ at the input end P0 is the value of the following equation.

As is clear from comparison of this value with the value of the fifth formula, in the series feeding circuit of the present embodiment, VS is larger than that in the conventional series feeding circuit.
Little deterioration of WR.

FIG. 2 shows another embodiment of the present invention.
The same reference numerals as those in the figure are the same. In the embodiment of FIG. 1 described above, the electric power remaining without being combined by the couplers 11, 12, 14, 15, 17, 18 was discarded to the matching terminators 51 to 53. It is taken out to terminals P3, P6, and P9 for effective use.

The operation in this case is similar to that of the series power feeding circuit shown in FIG.
The required amplitude distribution can be obtained by selecting the coupling degree of 2,14,15,17,18,20,21, and deterioration of VSWR can be suppressed as in the case of the series feed circuit of FIG.

In the above embodiment, each of the first series feeding circuits 1 to 3 and the second series feeding circuit 4 is cascaded with two or three couplers and two lines to obtain a distribution. Although the number of outputs is three, the present invention is not limited to this, and each of the plurality of first series power supply circuits on the output side of the entire circuit has If the number of the second series feeding circuits on the input side of the whole circuit is configured to be equal to or more than the number of the first series feeding circuits, the number of distributed outputs is the same as that of the conventional configuration. VSWR degradation can be reduced compared to a circuit that can obtain the same number of distributed outputs.

Further, in the above embodiment, the lines 37, 3 of the second series feeding circuit 4 are
The line length of 8 is 3L0, and the total line length of the lines in the corresponding first series feeding circuits 1 and 2 (L0 + L0 = 2L
0), but in the present invention,
The line lengths of these lines 37 and 38 correspond to the first
Total line length of the lines in the series feed circuits 1 and 2 (L0 + L0 = 2L0)
The same 2L0 may be used, and the same effect can be obtained in this case as well.

Further, in the above embodiment, the lines of the first series feeding circuits 1 to 3 are used.
The case where 31 to 36 have the same line length (L0) and the lines 37 and 38 of the second series feeding circuit 4 have the same line length (3L0) has been described, but in the present invention, these are different from each other. The line length may be the same, and the same effect can be obtained in this case as well. Further, in the above embodiment, the case where the coupling amount and the reflection coefficient of all the couplers 11 to 21 are equal to each other has been described, but in the present invention, these may be different from each other, and in this case, the same effect is obtained. Obtainable.

〔The invention's effect〕

As described above, according to the present invention, the couplers and the first lines are alternately connected in cascade, and from each coupler, or
A plurality of first series feeding circuits configured to obtain a distributed output from each coupler and the line at the final end, a coupler, and a second line are alternately cascaded, and each coupler and the final line are connected. A second series power supply circuit configured to obtain a distributed output from the end line, each of the plurality of distribution output terminals of the second series power supply circuit being connected to each of the plurality of first series power supply circuits. Connected to the input terminal of the second series feed circuit, and the line length of the second line of the second series feed circuit is equal to or equal to the total line length of the corresponding first line in the first series feed circuit. Since the input terminal of the second series feeding circuit is the input terminal of the whole circuit and the distribution output terminals of the plurality of first series feeding circuits are the distribution output terminals of the whole circuit, In comparison, it is possible to reduce the reflection coefficient in the entire circuit. As a result, there is an effect capable of suppressing the deterioration of VSWR.

[Brief description of drawings]

FIG. 1 is a block diagram showing a series feeding circuit according to an embodiment of the present invention, FIG. 2 is a block diagram showing another embodiment of the present invention, and FIG. 3 is a diagram showing a conventional series feeding circuit. 1-3 ... 1st series feeding circuit, 4 ... 2nd series feeding circuit, 11-21 ... Coupler, 31-36 ... 1st line, 37-
38 …… Second line, 50 ～ 53 …… Matching terminator, P1 ～ P13…
… Terminal. The same reference numerals in the drawings indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norio Takeuchi 8-1-1 Tsukaguchi Honcho, Amagasaki City, Hyogo Prefecture, Sanritsu Electric Co., Ltd. (56) Reference JP-A-57-127302 (JP, A) ) "Antenna Engineering Handbook" edited by The Institute of Electronics and Communication Engineers (Sho 55) Ohmsha P. 222-224

Claims (1)

[Claims] 1. A plurality of first and second lines configured to alternately connect the couplers and the first lines to obtain a distributed output from each of the couplers or from each of the couplers and the line at the final end. 1
A series feed circuit, a coupler, and a second line are alternately connected in cascade, and a second series feed circuit configured to obtain a distributed output from each coupler and the line at the final end is provided. Each of the plurality of distribution output terminals of the second series feeding circuit is connected to each input terminal of the plurality of first series feeding circuits, and the line length of the second line of the second series feeding circuit is Is equal to or longer than the total line length of the first line in the corresponding first series feeding circuit, and the input terminal of the second series feeding circuit is the input terminal of the whole circuit. And a distribution output terminal of the plurality of first series supply circuits as a distribution output terminal of the entire circuit.