JP2004282594A - Power controller and power control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smooth change of transmission power even in high output power and to suppress a spread of a transmission spectrum and spurious radiation while preventing the increase of circuit scale. <P>SOLUTION: First, a gain of a gain control amplifier 120 is smoothly lumped up (ST1000). Then, a timing control part 140 performs control so as to operate a power amplifier 130 in prescribed timing. At this time, the gain of the gain control amplifier 120 is lowered by a fixed gain value of the power amplifier 130 at the same time as the start of an operation of the power amplifier 130 (ST1100). After that, the gain of the gain control amplifier 120 is smoothly lumped up again (ST1200) during the operation of the power amplifier 130 and the final output power reaches desired transmission power. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power control device and a power control method, and more particularly to a power control device and a power control method for controlling power of a transmission signal in wireless communication.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a transmission device used in a wireless communication system, in order to control transmission power of a transmission signal, a gain control amplifier that variably controls a gain and amplifies an input signal and amplifies the input signal with a constant gain. A configuration including two amplifiers including a power amplifier may be adopted (for example, see FIG. 1 of Patent Document 1).
[0003]
In a transmission device including a gain control amplifier and a power amplifier, transmission power control is performed by combining gain control by the gain control amplifier and control of operation / stop of the power amplifier. At this time, the gain control amplifier smoothly changes the gain, thereby also smoothly changing the output power. On the other hand, in the power amplifier, only the operation / stop control is performed, so that the output power changes stepwise.
[0004]
By using a combination of amplifiers having different amplification characteristics in this way, the transmission power of the transmission signal is amplified to a desired power without a change in output power deviating from a certain standard.
[0005]
More specifically, as shown in FIG. 8 (a) ~ (c) , first, at time t _1, power amplifier starts to operate to amplify the transmission signal at a constant gain (FIG. 8 (c) ), then the time t ₁ after the gain control amplifier amplifies the transmission signal while smoothly changing the gain (Figure 8 (b)). As a result, the transmission power of the transmission signal changes as shown in FIG. 8A and is amplified to the desired power.
[0006]
[Patent Document 1]
JP-A-5-175771
[Problems to be solved by the invention]
By the way, especially in a transmission device that performs burst transmission, it is necessary to smoothly change transmission power at the time of rising or falling of transmission. This is because an abrupt change in transmission power causes a spread of transmission spectrum and spurious radiation.
[0008]
In the transmission device described above, the output power changes stepwise by the operation / stop control of the power amplifier, so that the transmission power does not change smoothly as shown in FIG. In this case, if the final transmission power is relatively low, the gain of the power amplifier can be relatively low, so that the spread of the transmission spectrum and spurious radiation can be suppressed to a certain level or less.
[0009]
However, when the final transmission power becomes high, the above-described transmission device has a problem that the spread of the transmission spectrum and the spurious radiation cannot satisfy the standards specified in, for example, the wireless communication system. In order to satisfy this criterion, the power amplifier is capable of continuously controlling the gain, the dynamic range of the gain control amplifier is widened, and the power of the transmission signal in the stage preceding the two amplifiers is made variable. It is conceivable to adopt a configuration, but in any case, there is a problem that a component and a circuit scale are increased.
[0010]
The present invention has been made in view of such a point, and it is possible to prevent a circuit size from becoming large, to smooth a change in transmission power even at a high output power, and to suppress the spread of a transmission spectrum and spurious radiation. It is an object to provide a control device and a power control method.
[0011]
[Means for Solving the Problems]
A power controller according to the present invention includes a first regulator that amplifies or attenuates signal power by changing a gain, and a second regulator that amplifies or attenuates signal power by a fixed gain value by switching operation / stop. And a controller for controlling operation timings of the first adjuster and the second adjuster, wherein the controller switches operation / stop of the second adjuster and simultaneously sets the first adjuster. Is discontinuously changed by the fixed gain value.
[0012]
According to this configuration, the second adjuster that switches the operation / stop to change the signal power by the fixed gain value switches the operation / stop and simultaneously fixes the gain of the first adjuster that can change the gain. Since the change is discontinuously changed by the gain value, the discontinuous change of the signal power accompanying the switching of the operation / stop of the second adjuster can be canceled by the change in the gain of the first adjuster, thereby increasing the circuit scale. , The change in signal power can be smoothed even at high output power, and the spread of transmission spectrum and spurious radiation can be suppressed.
[0013]
The power control device of the present invention employs a configuration in which the controller discontinuously reduces the gain of the first regulator by the fixed gain value at the same time that the second regulator starts operating.
[0014]
According to this configuration, the gain of the first adjuster is discontinuously reduced at the same time as the operation of the second adjuster is started, so that a discontinuous change in signal power at the time of rising power can be prevented.
[0015]
The power control device of the present invention employs a configuration in which the controller continuously changes the gain of the first regulator except when switching the operation / stop of the second regulator.
[0016]
According to this configuration, the gain of the first adjuster is continuously changed except when the operation / stop of the second adjuster is switched, so that the final signal power can always be continuously changed.
[0017]
The power control device of the present invention further includes an acquisition unit that acquires a parameter related to wireless transmission of a signal whose power has been adjusted by the first adjustment unit and the second adjustment unit, and the control unit includes: A configuration is adopted in which the timing of switching the operation / stop of the second adjuster is adjusted according to the acquired parameters.
[0018]
According to this configuration, the timing of switching the operation / stop of the second adjuster is adjusted according to the parameter related to the wireless transmission, so that more appropriate power control can be performed according to an external factor.
[0019]
The power control device of the present invention is configured such that the acquisition unit acquires, as parameters, at least one of a group consisting of a temperature, a transmission frequency for wirelessly transmitting a signal, a modulation scheme, and a desired transmission power. Take.
[0020]
According to this configuration, since any one of the temperature, the transmission frequency for wirelessly transmitting the signal, the modulation scheme, and the desired transmission power is used as a parameter, when performing transmission power control in wireless communication, More appropriate transmission power control can be performed according to the state.
[0021]
The power control device of the present invention further includes a monitor that monitors whether the second regulator has actually switched operation / stop, and wherein the controller has a function that the second regulator actually operates / stops. Only when the stop is switched, the gain of the first adjuster is discontinuously changed by the fixed value.
[0022]
According to this configuration, it is monitored whether or not the second adjuster has actually switched the operation / stop, and only when the second adjuster has actually switched, the gain of the first adjuster is discontinuously changed. Even if the switching of the operation / stop of the second regulator is delayed due to the presence of a capacitive load in the power supply of the regulator, the gain of the first regulator can be changed discontinuously at accurate timing. .
[0023]
A wireless communication device according to the present invention has a configuration including the power control device according to any of the above.
[0024]
According to this configuration, the same operation and effect as the power control device according to any of the above can be realized in the wireless communication device.
[0025]
A power control method according to the present invention includes a first regulator having a variable gain and a second regulator having a fixed gain value that is always constant. A power control method used in a power control device that controls signal power by switching operation / stop of a regulator, comprising: continuously changing a gain of the first regulator; The method further comprises the steps of discontinuously changing the gain of the first adjuster by the fixed gain value at the same time as switching the stop, and continuously changing the gain of the first adjuster again.
[0026]
According to this method, the second regulator that switches the operation / stop to change the signal power by the fixed gain value switches the operation / stop and simultaneously changes the gain of the first regulator discontinuously by the fixed gain value. Since the gain of the first adjuster is continuously changed except when the operation / stop of the second adjuster is switched, the discontinuous change of the signal power accompanying the change of the operation / stop of the second adjuster is determined by the first change. The change can be offset by the change in gain of the adjuster, and the change in signal power can be smoothed even at high output power, and the spread of transmission spectrum and spurious radiation can be suppressed, while preventing an increase in circuit scale.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
The gist of the present invention is that the gain control amplifier continuously changes the gain while the power amplifier is stopped, and then lowers the gain of the gain control amplifier once at the start of the operation of the power amplifier. Is to change it.
[0028]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0029]
(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a power control device according to Embodiment 1 of the present invention. The power control device illustrated in FIG. 1 includes a D / A conversion unit 100, a modulation unit 110, a gain control amplifier 120, a power amplifier 130, a timing control unit 140, and a transmission antenna 150.
[0030]
D / A conversion section 100 performs D / A conversion on transmission data.
[0031]
The modulator 110 modulates the analog signal obtained by the D / A conversion to obtain a modulated signal.
[0032]
The gain control amplifier 120 amplifies the modulation signal under the control of the timing control unit 140. The gain control amplifier 120 can smoothly change the output power by continuously changing the gain.
[0033]
The power amplifier 130 amplifies the output signal from the gain control amplifier 120 under the control of the timing control unit 140. Since the gain of the power amplifier 130 is set to a fixed value (hereinafter, this value is referred to as “fixed gain value”), the control by the timing control unit 140 only switches the operation / stop of the power amplifier 130. That is, the power amplifier 130 changes the output power discontinuously.
[0034]
The timing control unit 140 controls the gain control amplifier 120 and the power amplifier 130 to operate each amplifier at an appropriate timing. A method of controlling the gain control amplifier 120 and the power amplifier 130 by the timing control unit 140 will be described later in detail.
[0035]
The transmission antenna 150 transmits a transmission signal whose power is amplified by the gain control amplifier 120 and the power amplifier 130 to a desired transmission power.
[0036]
Next, a method of controlling the operation timings of the two amplifiers in the power control device configured as described above will be described with reference to FIGS.
[0037]
First, the transmission data is D / A-converted by the D / A conversion unit 100 to become an analog signal. This analog signal is modulated by the modulator 110, and the obtained modulated signal is input to the gain control amplifier 120.
[0038]
Thereafter, the gain control amplifier 120 and the power amplifier 130 are controlled by the timing control unit 140 in accordance with the flowchart shown in FIG.
[0039]
That is, first, the gain of gain control amplifier 120 is smoothly ramped up (ST1000). Then, at a predetermined timing, the timing control section 140 controls the power amplifier 130 to operate. At this time, at the same time as the operation of the power amplifier 130 starts, the gain of the gain control amplifier 120 is reduced by the fixed gain value of the power amplifier 130 (ST1100).
[0040]
As described above, when the operation of the power amplifier 130 is started, the gain of the gain control amplifier 120 is once discontinuously reduced by the fixed gain value so that the final signal of the signal that has passed through the two amplifiers with the operation of the power amplifier 130 is started. It is possible to prevent the output power from changing stepwise.
[0041]
Thereafter, during the operation of the power amplifier 130, the gain of the gain control amplifier 120 is smoothly ramped up again (ST1200), and the final output power reaches the desired transmission power.
[0042]
Accordingly, if the desired transmission power is equal to or less than the sum of the dynamic ranges of the gain control amplifier 120 and the power amplifier 130, these two amplifiers operate as if they were one high-output gain control amplifier. Output power can be changed smoothly. Further, such an operation is performed in a configuration in which only a circuit for appropriately controlling the operation timing of the conventional gain control amplifier and power amplifier is additionally provided, so that the circuit scale does not increase.
[0043]
FIGS. 3A to 3C are diagrams showing the time variation of the final output power, the gain of the gain control amplifier 120, and the gain of the power amplifier 130. FIG.
[0044]
Gain of the gain control amplifier 120 shown in FIG. 3 (b), will smoothly up from time t _1, at time t ₂ when the power amplifier 130 starts operating, once by a fixed gain value fraction of the power amplifier 130 noncontiguous Is falling. Then, at the same time t _2, the power amplifier 130 starts to operate, the gain as shown in FIG. 3 (c) is up to the non-continuous. Thus, mutually offset discontinuous change in gain of the two amplifiers, the final output power, as shown in FIG. 3 (a), do not change stepwise even at time t _2.
[0045]
The time _{t 2} later, one gain of the power amplifier 130 is constant at a fixed gain value (FIG. 3 (c)), the gain of the gain control amplifier 120, going up again smoothed (FIG. 3 (b)) .
[0046]
As a result, the final output power that has passed through the two amplifiers always changes smoothly and reaches the desired transmission power, as shown in FIG.
[0047]
As described above, according to the present embodiment, the gain of the gain control amplifier is smoothly changed while the power amplifier is stopped, and the gain of the gain control amplifier is fixed at the time when the operation of the power amplifier is started. The gain is reduced by the gain value, and then the gain of the gain control amplifier is changed smoothly again.This prevents the circuit size from increasing and smoothes the change in the transmission power even at high output power, thereby expanding the transmission spectrum and spurious radiation. Can be suppressed.
[0048]
(Embodiment 2)
A feature of the second embodiment of the present invention is that the operation timings of the gain control amplifier and the power amplifier are adjusted according to parameters related to power control, such as temperature and desired transmission power.
[0049]
FIG. 4 is a block diagram showing a configuration of a power control device according to Embodiment 2 of the present invention. In the power control device shown in the figure, the same parts as those in the power control device shown in FIG. 4 includes a D / A converter 100, a modulator 110, a gain control amplifier 120, a power amplifier 130, a timing controller 140a, a transmission antenna 150, and a parameter output unit 200.
[0050]
The parameter output unit 200 outputs parameters such as a temperature, a transmission frequency, a modulation scheme, and a desired transmission power to the timing control unit 140a.
[0051]
The timing control unit 140a adjusts the operation start timing of the power amplifier 130 according to the parameter output from the parameter output unit 200. Further, the timing control unit 140a controls the gain control amplifier 120 until the adjusted operation start timing of the power amplifier 130. Other operations are the same as those in the first embodiment.
[0052]
As described above, according to the present embodiment, since the operation start timing of the power amplifier is adjusted according to the parameters related to the power control, transmission power control can be performed more appropriately.
[0053]
(Embodiment 3)
The feature of the third embodiment of the present invention is that the operation state of the power amplifier is monitored to prevent the timing of decreasing the gain of the gain control amplifier and the operation start timing of the power amplifier from shifting.
[0054]
FIG. 5 is a block diagram showing a configuration of a power control device according to Embodiment 3 of the present invention. In the power control device shown in the figure, the same parts as those in the power control device shown in FIG. The power control device illustrated in FIG. 5 includes a D / A conversion unit 100, a modulation unit 110, a gain control amplifier 120, a power amplifier 130, a timing control unit 140b, a transmission antenna 150, and a monitoring unit 300.
[0055]
The monitoring unit 300 monitors the operation state of the power amplifier 130, and when the power amplifier 130 starts operating, notifies the timing control unit 140b of the fact.
[0056]
When notified of the start of the operation of the power amplifier 130 from the monitoring unit 300, the timing control unit 140b lowers the gain of the gain control amplifier 120 by the fixed gain value.
[0057]
In the first embodiment, when a capacitive load exists in the power supply of power amplifier 130, the actual operation start is delayed even if timing control section 140 controls power amplifier 130 to operate at a predetermined timing. there is a possibility. If the gain of the gain control amplifier 120 is reduced by a fixed gain value even though the operation start is delayed, the final output power will fluctuate greatly.
[0058]
Therefore, in the present embodiment, the monitoring unit 300 monitors the operating state of the power amplifier 130 so that the gain of the gain control amplifier 120 is reduced by the fixed gain value when the power amplifier 130 actually starts operating. To
[0059]
Next, a method of controlling the operation timings of the two amplifiers in the power control device configured as described above will be described with reference to FIGS.
[0060]
First, the transmission data is D / A-converted by the D / A conversion unit 100 to become an analog signal. This analog signal is modulated by the modulator 110, and the obtained modulated signal is input to the gain control amplifier 120.
[0061]
Thereafter, the gain control amplifier 120 and the power amplifier 130 are controlled by the timing control unit 140b according to the flowchart shown in FIG. In the flowchart shown in FIG. 2, the same parts as those in the flowchart shown in FIG.
[0062]
First, the gain of gain control amplifier 120 is smoothly ramped up to the fixed gain value of power amplifier 130 (ST1000). Then, at a predetermined timing, the timing control section 140b controls the power amplifier 130 to operate.
[0063]
At this time, monitoring section 300 monitors whether or not power amplifier 130 has actually started operation (ST2000). If operation has not started, gain control amplifier 120 continues to ramp up the gain smoothly. . On the other hand, when power amplifier 130 actually starts operating, the gain of gain control amplifier 120 is reduced by the fixed gain value of power amplifier 130 (ST2100).
[0064]
Thereafter, during the operation of the power amplifier 130, the gain of the gain control amplifier 120 is smoothly ramped up again (ST1200), and the final output power reaches the desired transmission power.
[0065]
In this way, the operation state of the power amplifier 130 is monitored, and the gain control amplifier 120 performs a smooth ramp-up until the power amplifier 130 actually starts operating. However, the final output power does not change stepwise.
[0066]
FIGS. 7A to 7C are diagrams showing the temporal changes of the final output power, the gain of the gain control amplifier 120, and the gain of the power amplifier 130. FIG.
[0067]
Gain of the gain control amplifier 120 shown in FIG. 7 (b), will smoothly up from time t _1, even after the time t ₂ to the timing controller 140b controls to initiate the operation of the power amplifier 130, the time t _It goes up smoothly until ₂ '. This is because, as shown in FIG. 7 (c), a power amplifier 130, also at time t ₂ to the timing controller 140b controls to initiate the operation of the power amplifier 130, he actually starts operating not, _'because the power amplifier 130 starts to operate at, from time t ₂ the time t _2' time t ₂ during is continued for gain control amplifier 120 is controlled to raise smoothly the gain. Therefore, the final output power, as shown in FIG. 7 (a), is not also changed stepwise at time t ₂ and time t _{2 '.}
[0068]
After the time t ₂ ′, the gain of the power amplifier 130 is fixed at a fixed gain value (FIG. 7C), while the gain of the gain control amplifier 120 increases smoothly again (FIG. 7B). ).
[0069]
As a result, the final output power that has passed through the two amplifiers always changes smoothly and reaches the desired transmission power, as shown in FIG.
[0070]
Thus, according to the present embodiment, the operating state of the power amplifier is monitored, the gain is smoothly changed by the gain control amplifier until the power amplifier actually operates, and the power amplifier actually starts operating. At this point, the gain of the gain control amplifier is reduced by the fixed gain value, and then the gain of the gain control amplifier is smoothly changed again. , The change in transmission power can be smoothed even at high output power, and the spread of transmission spectrum and spurious radiation can be suppressed.
[0071]
In the above embodiment, the description has been given of the case where the transmission power rises. However, the present invention is not limited to this and can be applied to the case where the transmission power falls.
[0072]
Specifically, first, after the gain of the gain control amplifier is smoothly decreased, the operation of the power amplifier is stopped, and at the same time, the gain of the gain control amplifier is increased by the fixed gain value of the power amplifier. Thereafter, the gain of the gain control amplifier may be ramped down again.
[0073]
【The invention's effect】
As described above, according to the present invention, while preventing an increase in circuit scale, it is possible to smoothly change the transmission power even at a high output power, and to suppress the spread of the transmission spectrum and spurious radiation.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a power control device according to a first embodiment of the present invention. FIG. 2 is a flowchart illustrating an operation of the power control device according to the first embodiment. FIG. FIG. 4 is a block diagram showing a configuration of a power control device according to Embodiment 2 of the present invention. FIG. 5 is a block diagram showing a configuration of a power control device according to Embodiment 2 of the present invention. FIG. 6 is a flowchart showing the operation of the power control apparatus according to the third embodiment. FIG. 7 is a diagram showing an example of the time change of the power in the third embodiment. FIG. 8 is the power in the conventional transmitting apparatus. Diagram showing an example of the time change of the symbol
Reference Signs List 100 D / A conversion section 110 Modulation section 120 Gain control amplifier 130 Power amplifiers 140, 140a, 140b Timing control section 150 Transmission antenna 200 Parameter output section 300 Monitoring section

Claims (8)

A first regulator that amplifies or attenuates signal power by changing a gain;
A second regulator for amplifying or attenuating signal power by a fixed gain value by switching between operation and stop;
A controller for controlling operation timing of the first adjuster and the second adjuster,
The controller is
A power control device, wherein the power of the first regulator is changed discontinuously by the fixed gain value at the same time that the operation / stop of the second regulator is switched. The controller is
The power control apparatus according to claim 1, wherein the gain of the first regulator is discontinuously reduced by the fixed gain value at the same time as the second regulator starts operating. The controller is
2. The power control device according to claim 1, wherein the gain of the first regulator is continuously changed except when the operation / stop of the second regulator is switched. An acquisition unit that acquires a parameter related to wireless transmission of a signal obtained by adjusting power by the first adjustment unit and the second adjustment unit,
The controller is
The power control device according to claim 1, wherein a timing of switching operation / stop of the second adjuster is adjusted according to the acquired parameter. 5. The apparatus according to claim 4, wherein the acquisition unit acquires at least one of a group consisting of a temperature, a transmission frequency for wirelessly transmitting the signal, a modulation scheme, and a desired transmission power as parameters. Power control device. A monitor that monitors whether the second adjuster has actually switched operation / stop,
The controller is
2. The power control device according to claim 1, wherein the gain of the first adjuster is discontinuously changed by the fixed value only when the second adjuster actually switches operation / stop. 3. A wireless communication device comprising the power control device according to claim 1. It has a first adjuster whose gain is variable and a second adjuster whose gain is always a fixed gain value, and changes the gain of the first adjuster and switches the operation / stop of the second adjuster. A power control method used in a power control device that controls signal power by:
Continuously changing the gain of the first regulator;
Switching the operation / stop of the second adjuster and simultaneously changing the gain of the first adjuster discontinuously by the fixed gain value;
Changing the gain of the first regulator continuously again;
A power control method comprising:

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