JP2522199B2 - Power amplifier - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power amplifier, and more particularly to distributing an input signal to N systems and amplifying the power for each system.
The present invention relates to a power amplification device that is then combined and output.

[0002]

2. Description of the Related Art As shown in FIG. 6, a conventional power amplifier device of this type includes a power distributor 2 for distributing an output signal from a signal source 1 to N systems (N is an integer of 2 or more), and a power distributor 2. Equal N system 8
Amplifiers 41 to 4 for amplifying each signal distributed to 1 to 8N
N, a power combiner 6 that combines the amplified outputs of the respective systems, and phase adjusters 31 to 3N that adjust the signal phases of the respective systems.

The signal from the signal source 1 is divided into equal power by the power divider 2 and is input to each of the amplifiers 41 to 4N via the phase adjusters 31 to 3N. Each amplifier 41
4N, the output signals from the phase adjusters 31 to 3N are amplified and supplied to the power combiner 6. In the power combiner 6, the respective inputs are combined and output.

In this combination, if the phases of the signals from the amplifiers 41 to 4N do not match at the input parts, reflected power occurs and the specified power is not output to the output of the power combiner 6. . Therefore, in order to make the phases from the signal source 1 to the input section of the power combiner 6 in-phase for all N systems,
First, the transmission line of the input section of the power combiner 6 is removed, the phase from the output section of the signal source 1 to the removed transmission line is measured, and the phase adjusters 31 to 3N are manually adjusted to have the same phase. The phase adjusters 31 to 3N are finely adjusted so that the maximum power can be obtained while observing the output power.

[0005]

In such a conventional power amplifying apparatus, the transmission line is removed for each system to adjust the phase of the signal of each system, and the phase is adjusted. Is increased (the number of N is increased), the number of work steps is increased, and it is difficult to perform accurate phase adjustment because of manual adjustment. Further, even when the phase of each amplification system gradually changes due to aging, there is a drawback that the same manual adjustment needs to be repeated.

It is an object of the present invention to provide a power amplification device which automatically and optimally adjusts the signal phase of each system.

[0007]

According to the present invention, a distribution means for distributing an input signal to N systems (N is an integer of 2 or more) and a corresponding system provided for each of these N system outputs. A power amplification device comprising N-system amplifying means for amplifying an output and a combining means for combining the amplified outputs of these N-systems, the system being provided corresponding to each of the N-systems and corresponding system from the combining means. And a phase control means for controlling the signal phase of each system so that the detected reflected power level of each system is within a preset level range. A power amplification device characterized by the above is obtained.

[0008]

The reflected power in the N system signal paths is detected by the directional coupler for each system, and the signal phase of each system is controlled according to each detected reflected power level, and the reflected power level is predetermined. It is automatically controlled so that it is within a small range.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, and the same parts as in FIG. 6 are designated by the same reference numerals. The signal from the signal source 1 is distributed to the N systems 81 to 8N by the power distributor 2 and is fed to the amplifier 41 via the phase adjusters 31 to 3N.
Input to 4N. These respective amplified outputs are combined by the power combiner 6 via the directional couplers 51 to 5N and derived as amplified outputs.

Each of the directional couplers 51 to 5N is a power combiner 6
Each reflected power of the own system at the input section of the phase control device 7 is extracted.
Respectively, and the phase adjustment of the phase adjusters 31 to 3N of each system is automatically performed according to the reflected power level of each system, and the reflected power level of each system is within a predetermined range. Will be controlled so that

Flow charts of the control operation in the phase controller 7 are shown in FIGS. First, Step 1
In 01 to 107, the reflected power levels of the respective input systems are all compared, and the system with the highest level is found. In each of the steps 101 to 107, “connection” is an abbreviation for “directional coupler”.

When it is determined in step 107 that the system with the maximum level is the first system, in step 108, the phase adjuster 31 of the first system is divided as desired within a range of ± 90 ° (for example, 10 ° each). And the reflected power levels in each phase are compared, and in step 109, the phase of the phase adjuster 31 when the reflected power level by the directional coupler 51 of the first system is minimized is determined. Select and fix.

When it is determined in step 107 that the system with the maximum level is the N-th system, step 110,
In step 111, the same processing as steps 108 and 109 is performed in the Nth system.

Next, in steps 112 to 116,
Next, the line with the highest level is found. Step 1
When it is determined in step 16 that the level of the second system is the next highest, steps 117 and 118 perform steps 108 and 109.
The same processing as the above is performed in the second system.

In step 119, the maximum level is found among the corresponding directional couplers for which the phase adjuster has not yet been adjusted, and in step 120, the corresponding phase adjuster is set in the range of ± 90 °. In the same manner as described above, the reflected power levels at the respective phases are divided by dividing by 10 °, for example, and the phase of the phase adjuster when it becomes the minimum is selected and fixed.

When the adjustment is completed in all the systems in step 121, it is determined in step 122 whether the reflected power level by each directional coupler is within a predetermined minute range. If so, the adjustment ends, but if not, the processing shown in the above steps is repeated again for fine adjustment.

In this way, if the reflected power levels of all the systems are within the minute range, the fine adjustment is completed, and the power combiner 6 can perform almost ideal in-phase combining and easily obtain the specified power. It will be.

The power distributor 2 is, as shown in FIG.
A transmission line having a characteristic impedance of 50Ω at the input part and each output part, and a length λ / 4 (λ is a wavelength) connecting the transmission line,
This is a so-called octopus-type power distributor composed of a transmission line having a characteristic impedance of 50 / N ^1/2 (Ω).
The output signal from the signal source 1 is evenly distributed to each output by the power distributor 2.

As shown in FIG. 4 (B), the power combiner 6 has an output part and an input part inverted from those in FIG. 4 (A). Line and output part with characteristic impedance of 50Ω, connecting them λ / 4, characteristic impedance 50 / N
It is an octopus foot type power divider composed of ^1/2 (Ω) transmission lines.

FIG. 5 is a block diagram showing another example of the power distributor and the power combiner, and the same effect can be obtained even if the power distributor or the power combiner is arbitrarily replaced in the above-mentioned example. This power distributor and power combiner are octopus-type power distributors and power combiners in which the input part and the output part are inverted, as in FIG. 4, and the output part of the power distributor and the input part of the power combiner. Length λ / 4, characteristic impedance 50N
^1/2 (Ω) transmission line is connected.

[0022]

As described above, according to the present invention, the reflected power generated at the input part of the power combiner is detected and the phase adjuster is automatically controlled so that the reflected power is minimized. This has the effect of enabling accurate and sharp phase adjustment and reducing the number of adjustment steps as compared with the case of manually adjusting the phase.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing a part of an operation flowchart of an embodiment of the present invention.

FIG. 3 is a diagram showing a part of an operation flowchart of an embodiment of the present invention.

FIG. 4A is a diagram showing an example of a power divider, and FIG. 4B is a diagram showing an example of a power combiner.

5A is a diagram showing another example of a power distributor, FIG.
FIG. 6 is a diagram showing another example of the power combiner.

FIG. 6 is a block diagram showing an example of a conventional power amplifier.

[Explanation of symbols]

 1 Signal Source 2 Power Distributor 31-3N Phase Adjuster 41-4N Power Amplifier 51-5N Directional Coupler 6 Power Combiner 7 Phase Controller 81-8N 1st-Nth System

Claims (4)

(57) [Claims] 1. Input system for N systems (N is an integer of 2 or more)
Power amplifier including a distributing means for distributing to the N system, an N system amplifying means provided corresponding to each of these N system outputs for amplifying an output of the corresponding system, and a synthesizing means for synthesizing these N system amplified outputs. In the apparatus, the detecting means is provided corresponding to each of the N systems and detects the reflected power level from the synthesizing means to the corresponding system, and the detected reflected power level of each of these systems is preset. And a phase control means for controlling the signal phase of each system so as to be within the level range. 2. The phase control means is provided for each of the N systems and adjusts the signal phase of the corresponding system, and each of the phase adjusters according to the reflected power level of the N system. The power amplification device according to claim 1, further comprising a controller that controls the above. 3. The controller controls the phase adjuster sequentially from a system having a higher level among the reflected power levels of the N systems so that the reflected power level of each system falls within the level range. The power amplification device according to claim 2, wherein 4. The power amplification device according to claim 1, wherein the detection means is a directional coupler.