JPS6040031Y2 - Signal branching and combining device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a signal branching/synthesizing device used, for example, for parallel synthesis of power amplifiers from HF band to VHF band.
Regarding branching and combining devices.

Generally, in high-power transistor transmitters such as broadcasting equipment, it is difficult to realize high-power transistors, and parallel synthesis of power amplifiers is adopted to provide a redundant system of power amplifiers. Frequently used.

Conventionally, 3dB couplers, Wilkinson type branching synthesizers, etc. have been commonly used for parallel synthesis of power amplifiers in the frequency band above VHFHF, but since the wavelength is longer in the frequency band below VHFHF, the above It is becoming extremely difficult to realize such a branch/combiner.

For this reason, a 180 degree hybrid branch/combiner as shown in FIG. 1 is often used for parallel synthesis of power amplifiers in frequency bands near the HF band.

That is, the signal applied to the unbalanced terminal 1 is divided into two parts by the balanced/unbalanced conversion transformer 2 between the balanced terminals 3, 4 and the ground, each with a phase difference of 180 degrees.

The in-phase component and unbalanced amplitude component between the balanced terminals 3 and 4 are detected by the in-phase component detection transformer 5 at the in-phase terminal 6.

The component appearing at this common mode terminal 6 is the resistor 7 for absorbing the common mode component.
be absorbed into.

Conversely, if signals with a phase difference of 180 degrees are added between the balanced terminals 3 and 4 and the ground, they are combined and can be taken out between the unbalanced terminal 1 and the ground.

In order for this 180-degree hybrid branch signal generator to operate as described above, the impedance between terminals 1, 3, 4, and 6 and the ground must be in a constant relationship.

That is, if the impedance between the unbalanced terminal 1 and the ground is R, the impedance between the balanced terminals 3 and 4 and the ground is R/
2, and the impedance between common-mode terminal 6 and ground is R/
4, so it cannot be used, for example, for parallel synthetic leather in a power amplifier in a system that is generally unified to a 50Ω system.

Further, three of these 180-degree hybrid branch combiners are combined to form a four-branch combiner as shown in FIG.

Now, if the impedance between the unbalanced terminal 1 and the ground is 500, the impedance between the balanced terminals 3 and 4, which are branch terminals, and the ground between the balanced terminals 3 and 4 and the ground will be 1/4 of 12.5Ω, respectively, and the input and output will match this impedance. It became necessary to create a power amplifier with impedance, and the cable and connector for connecting this power amplifier and the four-branch combiner had to be special, and maintenance and measurements were also very complicated.

The present invention eliminates the above-mentioned drawbacks and provides a four-branch combiner signal branching/combining device that uses multiple 180-degree hybrid branch combiners to make the impedance of the combining terminal and the four branch terminals the same value. The purpose is to

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 shows an embodiment of the present invention.

That is, the first 180 degree hybrid branch combiner 11 uses a 180 degree hybrid branch combiner as shown in FIG. 1, and the second 180 degree hybrid branch combiner 15 and the third 180 degree hybrid branch combiner The combiner 17 is constructed by connecting resistors 35 and 36 for absorbing negative phase components between the balance terminals 19 and 20, and between the balance terminals 21 and 22 of each 180-degree hybrid branch combiner as shown in FIG. A circuit is used that eliminates the unbalanced conversion transformer.

The unbalanced terminal 12 of the first 180-degree hybrid branch-combiner 11 is used as a composite terminal, and the balanced terminals 13 and 14 of the first 180-degree hybrid branch-combiner 11 are connected to second terminals, respectively.
In-phase terminal 16 of 180 degree hybrid branch combiner 15
and the in-phase terminal 18 of the third 180-degree hybrid branch combination device 17 are connected, and each balanced terminal 19° 20 of the second and third 180-degree hybrid branch combination device 15, 17 is connected.
This is a 4-branch combination device with 21 and 22 as branch terminals.

That is, in the first 180-degree hybrid branching unit 11, the unbalanced terminal 12 is connected to one end of the balanced/unbalanced conversion transformer 23, and the unbalanced terminals 13 and 14 are connected to the other end.

A common mode detection transformer 24 is connected between the balanced terminals 13 and 14.
is connected to the in-phase terminal 25, and the in-phase terminal 25 is connected to the connection point of the series-connected coils of the transformer 24.
5 is grounded via a common-mode component absorbing resistor 26.

An in-phase detection transformer 29 is connected to the balanced terminals 19 and 20 of the second 180-degree hybrid branch-combiner 15, and the in-phase terminal 16 is connected to the in-phase detection transformer 29.

A negative phase component absorbing resistor 35 is connected between the balanced terminals 19 and 20.

In the same way, the third 180-degree hybrid branch gaikaiki 1
An in-phase detection transformer 33 is connected to the balanced terminals 21 and 22 of 7, and this in-phase detection transformer 33 is connected to the in-phase terminal 1.
8 is connected.

A resistor 36 for absorbing a negative phase component is provided between the balanced terminals 21 and 22.
is connected.

Then, the second 180-degree hybrid branch-combiner 1 is connected to the balanced terminal 13 of the first 180-degree hybrid branch-combiner 11.
The in-phase terminal 16 of the third 180-degree hybrid branch combiner 17 is connected to the balanced terminal 14 of the first 180-degree hybrid branch combiner 11.

The balanced/unbalanced conversion transformer 23 and in-phase detection transformers 24, 29.33 may be transmission line type transformers such as coaxial cables, pair cables, or strip lines having a predetermined impedance. They may be connected in series.

Further, these coaxial cables or pair cables may be left in the air, passed through the core, or wound around the core.

Now, the balanced terminals 19, 20 and 21.22 which are branch terminals
Let R' be the impedance connected between each ground and the opposite phase component absorbing resistors 35 and 36 connected between each balance terminal 19 and 20 and between 21 and 22.

In this case, the impedance seen from each in-phase terminal 16 and 18 to the branch terminal side is R'/2.

Furthermore, the in-phase terminals 16 and 18 of these second and third 180-degree hybrid branch combiners 15 and 17 are connected to the first 180-degree hybrid combiner 15 and 17.
Since it is connected to the balanced terminals 13 and 14 of the 4-branch combination device 11, the in-phase component absorption resistor 26 between the in-phase terminal 25 and the ground becomes R'/4, which is the composite terminal of the 4-branch combination device. It can be seen that the impedance when looking from the unbalanced terminal 12 to the branch terminal side is R'.

That is, in this four-branch combining device, a signal applied to the unbalanced terminal 12, which is a composite terminal, is first transferred to the balanced terminal 13.1.
4, which appear as anti-phase branches in the second and third 1
In-phase terminal 1 of 80 degree hybrid branch combiner 15, 17
6.18, so the balanced terminal 1 which is a branch terminal
It will be in-phase branched to 9.20 and 21.22,
4 where the composite terminal and branch terminal have equal impedance
A branching and joining command device can be realized.

As described above, according to the present invention, it is possible to provide a signal branching and combining device in which the impedance of the combining terminals 19 and the branching terminals are equal from the band to the VHF band. can be facilitated.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing an example of a general 180-degree hybrid gathering device, Figure 2 is a circuit diagram showing a conventional four-branch gathering device, and Figure 3 is a circuit diagram showing an embodiment of the present invention. be. 11.15.17...180 degree hybrid branching device, 12...Unbalanced terminal, 13,14,
19.20,21,22...Balanced terminal, 16,
18.25...In-phase terminal, 23...Balanced unbalanced conversion transformer, 24,29,33...
In-phase component detection transformer, 26... Resistor for absorbing in-phase component, 35.36... Resistor for absorbing negative-phase component.

Claims (1)

[Scope of utility model registration request] a first having an unbalanced terminal, a common mode terminal and two balanced terminals;
180 degree hybrid branch signal generator, in-phase terminal and 2
The second type has two balanced terminals, and a resistor for absorbing a negative phase component is connected between the balanced terminals to eliminate the balanced/unbalanced conversion transformer.
a third 180 degree hybrid branch combiner, and a second 180 degree hybrid branch combiner connected to both balanced terminals of the first 180 degree hybrid branch combiner. Connect the in-phase terminals of the third 180 degree hybrid branch combiner, terminate the in-phase terminals of the first 180 degree hybrid branch combiner via a resistor, and The unbalanced terminal of the second. A signal branching and combining device in which each balanced terminal of the third 180-degree hybrid branching and combining device is used as a branching terminal.