CN100411307C - Sending method and sending device - Google Patents

Abstract

The present invention relates to a transmission method and a transmission device for improving the linearity and power efficiency of a power amplifier in a wireless communication system. Disclosed is a transmission method and a transmission device that automatically adjust the delay amount of a delay device to reduce out-of-band distortion of a transmission signal without manual adjustment operations, thereby realizing accurate timing. In this transmission device, the first delay means adjusts control timing for controlling the voltage of the power amplifying means. The divider divides a part of the output of the power amplifier for feeding back. The distortion adjustment means calculates the distortion component of the transmission signal by using the signal fed back from the distributor, and automatically adjusts the delay amount of the first delay means to reduce the distortion component. Accordingly, less distortion and high power efficiency can be obtained without manual adjustment operations.

Description

Sending method and sending device

technical field

The present invention relates to a transmission method and a transmission device for improving the linearity and power efficiency of a power amplifier in a wireless communication system.

Background technique

A power amplifier of a transmitting device in a wireless communication system is the circuit that consumes the most power in the entire device, so it is desired to improve its power efficiency. In order to carry out large-capacity data transmission in recent years, wireless communication systems use high-speed broadband linear modulation signals, instead of using so-called C-class or D-class nonlinear amplifiers with high power efficiency, but to compensate (output maximum amplitude level and The difference in the output saturation power level) has an appropriate margin to use a so-called A-class or AB-class linear amplifier having poor power efficiency.

In order to improve the power efficiency of the transmitting apparatus, if the compensation is reduced, the distortion increases and the spectrum spreads, which may interfere with adjacent communication channels.

An example of a method for solving the problems of improving the power efficiency of a power amplifier and securing linearity is the Envelope Elimination and Restoration (EER: Envelope Elimination and Restoration) (Kahn, "Single-sideband transmission by envelope elimination and restoration", Proc. .IRE, July 1952, pp.803-806). The transmission device based on this method decomposes the transmission signal into an amplitude component and a phase component, and the phase component that becomes a constant envelope signal is amplified by a nonlinear amplifier with high power efficiency, and the power supply of the amplifier is controlled according to the amplitude component, thereby, Perform reconstruction of the amplitude component and phase component.

FIG. 7 is an example of the configuration of a conventional transmitter for envelope removal and restoration. The distributor 302 distributes the input transmission RF signal 301 to the amplitude limiting circuit 303 and the envelope detection circuit 306 . The amplitude limiting circuit 303 limits the amplitude of the signal distributed from the distributor 302 to obtain the phase component of the transmission RF signal 301 . The delay circuit 304 gives an appropriate delay to the output of the amplitude limiting circuit 303 .

The power amplifier 305 amplifies the output of the delay circuit 304 to a desired power value. The envelope detection circuit 306 performs envelope detection on the signal from the distributor 302 to obtain the amplitude component of the transmission RF signal 301 . The voltage control DC converter 307 outputs a voltage for controlling the power amplifier 305 based on the signal output from the envelope detection circuit 306 .

For example, when the power amplifier 305 is a FET (Field Effect Transistor), the voltage from the voltage control DC converter 307 controls the drain voltage of the power amplifier 305 to perform amplitude modulation. Through the above operations, the output of the power amplifier 305 becomes a signal reconstituted with an amplitude component and a phase component, and is transmitted from the antenna 308 .

The envelope tracking method is a known technique as another method for solving the problems of improving power efficiency and ensuring linearity. (Raab, "Power amplifiers and transmitters for RF and microwave" Raab, F.H.; Asbeck, P.; Cripps, S.; Kenington, P.B.; Popovic, Z.B.; Pothecary, N., Sevic, J.F.; Sokal, N.O.; Microwave Theory and Techniques, IEEE Transactions on, Volume: 50, Issue: 3, March 2002, Page(s): 814-826).

This method detects the amplitude component of the transmission RF signal by an envelope detector, and controls the voltage supplied to the power amplifier based on the detected amplitude component. Since the original transmission RF signal having not only the phase component but also the amplitude fluctuation is input to the power amplifier, the power amplifier must be a linear amplifier.

In such a conventional configuration, it is necessary to precisely match the timing of the voltage control with the transmission signal by means of a delay circuit. FIG. 8A shows a frequency spectrum of a transmission signal when there is a timing error in voltage control, and FIG. 8B shows a frequency spectrum when there is no timing error in voltage control.

When there is a timing error, as shown in FIG. 8A , a distortion component 401 is generated, causing performance degradation of the transmitted signal and interference to adjacent channels. When there is no timing error, as shown in FIG. 8B, a transmitted signal 402 without distortion can be obtained.

However, the above-mentioned timing adjustment is a manual adjustment operation, which is troublesome. In addition, the once-adjusted timing may not be able to follow changes in device characteristics due to subsequent temperature changes or aging changes.

Contents of the invention

The present invention provides a transmission method and a transmission device for realizing accurate timing by automatically adjusting the delay amount of a delay device to reduce out-of-band distortion components of a transmission signal without manual adjustment operations.

The transmission method of the present invention is a transmission method for performing voltage control of the power amplifying device according to the envelope amplitude of the transmission signal, distributes the output signal from the power amplifying device to the transmission signal and the feedback signal, and calculates the transmission signal by the feedback signal. Distortion component of the signal, transmission method that automatically controls the control timing of the voltage of the control power amplifying device to decrease.

According to the above method, the delay amount of the delay device can be automatically adjusted to reduce the out-of-band distortion component of the transmission signal without manual adjustment operation, so as to realize accurate timing.

The transmitting device of the present invention has: a first delay device for adjusting the control timing of the voltage of the power amplifying device; a distributor for distributing and feeding back the output of the power amplifying device; and a device for calculating the transmission signal using the signal fed back by the distributor The distortion component is a distortion adjusting means that automatically adjusts the delay amount of the first delay means in order to reduce the distortion component.

According to the above configuration, the delay amount of the delay means can be automatically adjusted to reduce the out-of-band distortion component of the transmission signal without manual adjustment operation, thereby realizing accurate timing.

Description of drawings

Fig. 1 is a block diagram of a transmission device according to a first embodiment of the present invention.

Fig. 2 is a block diagram of a transmission device according to a second embodiment of the present invention.

Fig. 3 is a block diagram of a transmission device according to a third embodiment of the present invention.

Fig. 4 is a block diagram of a transmission device according to a fourth embodiment of the present invention.

Fig. 5 is a block diagram of a transmission device according to a fifth embodiment of the present invention.

Fig. 6 is a block diagram of a transmission device according to a sixth embodiment of the present invention.

Fig. 7 is a block diagram of a conventional transmission device.

FIG. 8 is a diagram showing spectral characteristics of a transmission signal when there is a timing error in the voltage control of the power amplifier and when there is no timing error.

Detailed ways

Embodiments of the present invention will be described below using diagrams.

first embodiment

Fig. 1 is a block diagram of a transmission device according to a first embodiment of the present invention. The delay circuit 102 delays and outputs the input signal. The DA converter 103 converts the input signal into an analog signal. The frequency conversion circuit 104 up-converts the input signal into an RF signal. The power amplifier 105 amplifies the input signal. The amplitude calculation circuit 106 calculates and outputs the amplitude component of the input signal.

The delay circuit 107 delays the input signal. The DA converter 108 converts the input signal into an analog signal. The voltage control DC converter 109 outputs a voltage for controlling the power amplifier 105 based on the output from the DA converter 108 . The distributor 110 distributes the output from the power amplifier 105 to the antenna 111 and the frequency conversion circuit 112 .

The antenna 111 transmits the signal distributed by the distributor 110 . The frequency conversion circuit 112 converts the frequency of the signal distributed by the distributor 111 . The AD converter 113 converts the input signal into a digital signal. The out-of-band power calculation circuit 114 calculates the out-of-band power in the input signal. The delay amount calculation circuit 115 calculates and outputs the delay amount to reduce the out-of-band power obtained by the out-of-band power calculation circuit 114 .

In the above configuration, the operation of the transmission device will be described.

The delay circuit 102 delays the transmission baseband signal 101 only by the delay amount indicated by the delay amount calculation circuit 115 . The DA converter 103 converts the signal from the delay circuit 102 into an analog signal. The frequency conversion circuit 104 up-converts the signal from the DA converter 103 into a desired RF signal. The power amplifier 105 amplifies the signal from the frequency conversion circuit 104 to a desired power value.

Since the signal input to the power amplifier 105 is a linearly modulated signal accompanied by fluctuations in the envelope amplitude, a linear amplifier such as class A or class AB is used as the type of power amplifier.

On the other hand, the amplitude calculation circuit 106 calculates and outputs the amplitude component of the transmission baseband signal. The delay circuit 107 delays the amplitude component value output from the amplitude calculation circuit 106 by the delay amount instructed by the delay calculation circuit 115 . The DA converter 108 converts the signal from the delay circuit 107 into an analog signal. The voltage control DC converter 109 outputs a voltage for controlling the power amplifier 105 based on the output from the DA converter 108 .

For example, when the power amplifier 105 is a FET, its drain voltage or gate voltage is controlled by the voltage from the voltage control DC converter 109 .

The distributor 110 distributes the output from the power amplifier 105 to the antenna 111 and the frequency conversion circuit 112 . The antenna 111 transmits the signal distributed by the distributor 110 . The frequency conversion circuit 112 down-converts the signal distributed by the distributor 110 into a baseband signal or an IF signal. The AD converter 113 converts the signal from the frequency conversion circuit 112 into a digital signal.

The out-of-band power calculation circuit 114 calculates the out-of-band power in the signal from the AD converter 113 . The out-of-band power is, for example, an adjacent channel leakage power value or an adjacent channel leakage power ratio. When the adjacent channel leakage power ratio exceeds a predetermined value due to failure of the power amplifier 105 or the like, the operation of the device is stopped, thereby preventing abnormal signal transmission from the antenna.

The delay amount calculation circuit 115 calculates the delay amount to reduce the out-of-band power obtained by the out-of-band power calculation circuit 114, and outputs it to the delay circuits 102 and 107.

Therefore, because the delay amount calculation circuit 115 sets the delay amounts of the delay circuits 102, 107 so that the out-of-band power obtained by the out-of-band power calculation circuit 114 becomes small, and the power amplifier by the voltage control DC converter 109 is automatically performed. The control timing of 105 is adjusted, so that the present transmitting apparatus can obtain less distortion and high power efficiency.

In addition, the delay circuits 102 and 107 can be realized with a configuration of a buffer memory or a tapped delay line in necessary delay units. When using these to change the delay amount, the former is performed by changing the buffer amount, and the latter is performed by changing the tap coefficient.

2nd embodiment

Fig. 2 is a block diagram of a transmission device according to a second embodiment of the present invention.

The arithmetic circuit 218 is composed of an amplitude calculation circuit 202 and a phase calculation circuit 203 . The amplitude calculation circuit 202 calculates the amplitude component of the input transmission baseband signal 201 . The phase calculation circuit 203 calculates the phase component of the input transmission baseband signal 201 . The delay circuit 204 delays the output signal of the phase calculation circuit 203 .

The DA converter 205 converts the output of the delay circuit 204 into an analog signal. The voltage controlled oscillator 206 performs phase modulation based on the output of the DA converter 205 . The frequency conversion circuit 207 converts the frequency of the output of the voltage controlled oscillator 206 . The power amplifier 208 amplifies the output of the frequency conversion circuit 207 to a desired power value. The delay circuit 209 delays the output signal of the amplitude calculation circuit 202 .

The DA converter 210 converts the output signal of the delay circuit 209 into an analog signal. The voltage control DC converter 211 outputs a voltage for controlling the power amplifier 208 based on the output signal from the DA converter 210 . The distributor 212 distributes the signal from the power amplifier 208 to the antenna 213 and the frequency conversion circuit 214 . The antenna 213 transmits the signal from the distributor 212 .

The frequency conversion circuit 214 converts the frequency of the signal from the distributor 212 . The AD converter 215 converts the signal from the frequency conversion circuit 214 into a digital signal. The out-of-band power calculation circuit 216 calculates the out-of-band power in the input signal. The delay amount calculation circuit 217 calculates and outputs a delay amount in order to reduce the out-of-band power obtained by the out-of-band power calculation circuit 216 .

Next, the operation of the transmitting device in the above configuration will be described.

The arithmetic circuit 218 receives the transmission baseband signal 201, and calculates the amplitude component by the amplitude calculation circuit 202 and the phase component by the phase calculation circuit 203, respectively. The delay circuit 204 delays the phase component output from the phase calculation circuit 203 by the delay amount instructed by the delay calculation circuit 217 . The DA converter 205 converts the signal from the delay circuit 204 into an analog signal.

The voltage controlled oscillator 206 performs phase modulation based on the signal output from the DA converter 205 . The frequency conversion circuit 207 up-converts the output of the voltage controlled oscillator 206 into an RF signal. The power amplifier 208 amplifies the output of the frequency conversion circuit 207 to a desired power value. Since the signal input to the power amplifier 208 is a constant-envelope signal, the power amplifier 208 can use a non-linear amplifier such as class C or class D with excellent power efficiency.

On the other hand, the delay circuit 209 delays the amplitude component output from the amplitude calculation circuit 202 by the delay amount specified by the delay calculation circuit 217 . The DA converter 210 converts the signal from the delay circuit 209 into an analog signal. The voltage control DC converter 211 outputs a voltage for controlling the power amplifier 208 based on the signal output from the DA converter 210 .

For example, when the power amplifier 208 is a FET, amplitude modulation is performed by controlling the drain voltage of the power amplifier 208 using the voltage from the voltage control DC converter 211 . The distributor 212 distributes the output of the power amplifier 208 that has received the amplitude modulation to the antenna 213 and the frequency conversion circuit under the control of the voltage control DC converter 211 . The antenna 213 transmits the signal distributed by the distributor 212 .

The frequency conversion circuit 214 down-converts the signal distributed by the distributor 212 into a baseband signal or an IF signal. The AD converter 215 converts the signal from the frequency conversion circuit 214 into a digital signal. The out-of-band power calculation circuit 216 calculates the out-of-band power of the transmission signal included in the output of the AD converter 215 . As the out-of-band power, an adjacent channel leakage power value or an adjacent channel leakage power ratio can be used.

When the out-of-band power exceeds a predetermined value due to a failure of the power amplifier 208 or the like, the operation of the device is stopped to prevent abnormal signal transmission from the antenna 213 . The delay amount calculation circuit 217 calculates the delay amount in the direction in which the out-of-band power becomes smaller based on the output of the out-of-band power calculation circuit 216, and outputs it to the delay circuits 204 and 209.

Therefore, since the delay amount calculation circuit 217 sets the delay amounts of the delay circuits 204, 209 in order to reduce the out-of-band power obtained by the out-of-band power calculation circuit 216, and automatically performs the power output by the voltage control DC converter 211 Since the control timing of the amplifier 208 is adjusted, the present transmitting apparatus can obtain low distortion and high power efficiency.

3rd embodiment

Fig. 3 is a block diagram of a transmission device according to a third embodiment of the present invention.

The arithmetic circuit 518 is composed of an amplitude calculation circuit 502 and a phase calculation circuit 503 . The amplitude calculation circuit 502 calculates the amplitude component of the input transmission baseband signal 501 . The phase calculation circuit 503 calculates the phase component of the input transmission baseband signal 501 . The delay circuit 504 delays the output signal of the phase calculation circuit 503 .

The DA converter 505 converts the output of the delay circuit 504 into an analog signal. The voltage controlled oscillator 506 performs phase modulation based on the output of the DA converter 505 . The frequency conversion circuit 507 converts the frequency of the output signal of the voltage control oscillator 506 . The power amplifier 508 amplifies the output of the frequency conversion circuit 507 to a desired power value. The delay circuit 509 delays the output signal of the amplitude calculation circuit 502 .

The DA converter 510 converts the output signal of the delay circuit 509 into an analog signal. The voltage control DC converter 511 outputs a voltage for controlling the power amplifier 508 based on the output signal from the DA converter 210 . The distributor 512 distributes the signal from the power amplifier 508 to the antenna 513 and the frequency conversion circuit 514 . The antenna 513 transmits the signal from the distributor 512 .

The frequency conversion circuit 514 converts the frequency of the signal from the distributor 512 . The AD converter 515 converts the signal from the frequency conversion circuit 214 into a digital signal. The error component calculation circuit 516 calculates the error component between the output signal of the AD converter 515 and the transmission baseband signal 501 . The delay amount calculation circuit 517 calculates and outputs the delay amount in order to reduce the error component obtained by the error component calculation circuit 516 .

The transmission device according to the third embodiment of the present invention is configured such that the delay amount calculation circuit 517 calculates the delay amount based on the calculation result of the error component calculation circuit 516 . Therefore, descriptions of the same parts as those of the second embodiment will be omitted below, and the operations will be described focusing on the differences.

The processing from calculation circuit 518 to calculate the amplitude component and phase component of transmission baseband signal 501 until power amplifier 508 transmits from antenna 513 via distributor 512 is the same as in the second embodiment.

The frequency conversion circuit 514 down-converts the signal distributed by the distributor 512 into a baseband signal. The AD converter 515 converts the signal from the frequency conversion circuit 514 into a digital signal. The error component calculation circuit 516 inputs the output signal of the AD converter 515 and the transmission baseband signal 501, and calculates the error component between the two signals at each preset sampling time.

The delay amount calculation circuit 517 calculates the delay amount in the direction in which the error component becomes smaller based on the error component from the error component calculation circuit 516 , and outputs it to the delay circuits 504 and 509 .

Therefore, since the delay amount calculation circuit 517 sets the delay amounts of the delay circuits 504, 509 in order to reduce the error component obtained by the error component calculation circuit 516, and automatically performs the power amplifier by the voltage control DC converter 511 The control timing of 508 is adjusted, so the transmission device can obtain less distortion and high power efficiency.

Example 4

Fig. 4 is a block diagram of a transmission device according to a fourth embodiment of the present invention.

The arithmetic circuit 602 is composed of an amplitude calculation circuit 615 and a phase calculation circuit 616 . The amplitude calculation circuit 615 calculates the amplitude component of the input transmission baseband signal 601 . The phase calculation circuit 616 calculates the phase component of the input transmission baseband signal 601 . The DA converter 603 converts the output of the phase circuit 616 into an analog signal.

The filter 604 passes specific frequencies among the output signals of the DA converter 603 . The delay circuit 605 delays the output signal of the filter 604 . The phase modulation circuit 606 performs phase modulation based on the output of the delay circuit 605 . The power amplifier 607 amplifies the output of the phase modulation circuit 606 to a desired power level. The DA converter 608 converts the output signal of the amplitude calculation circuit 615 into an analog signal.

The filter 609 passes a specific frequency among the output signals of the DA converter 608 . The delay circuit 610 delays the output signal of the filter 609 . The amplitude modulation circuit 611 outputs the voltage for controlling the power amplifier 607 according to the output signal of the delay circuit 610 . The distributor 612 distributes the signal from the power amplifier 607 to the antenna 611 and the distortion detection circuit 614 .

The antenna 613 transmits the signal from the splitter 612 . The distortion detection circuit 614 detects the distortion of the signal from the distributor 612 and sets the delay amount of the delay circuits 605 , 610 .

Next, the operation of the transmitting device in the above configuration will be described.

The arithmetic circuit 602 receives the transmission baseband signal 601, and calculates the amplitude component by the amplitude calculation circuit 615 and the phase component by the phase calculation circuit 616, respectively. DA converter 603 converts the phase component output from phase calculation circuit 616 into an analog signal. The filter 604 passes specific frequencies among the outputs from the DA converter 603 and excludes unnecessary frequencies.

The delay circuit 605 delays the signal from the filter 604 by the delay amount set by the distortion detection circuit 614 . The phase modulation circuit 606 performs phase modulation based on the signal output from the delay circuit 605 . The power amplifier 607 amplifies the output of the phase modulation circuit 606 to desired power.

On the other hand, DA converter 608 converts the amplitude component output from amplitude calculation circuit 615 into an analog signal. The filter 609 passes specific frequencies among the outputs from the DA converter 608 and excludes unnecessary frequencies. The delay circuit 610 delays the signal from the filter 609 by the delay amount set by the distortion detection circuit 614 .

The amplitude modulation circuit 611 outputs a voltage for controlling the power amplifier 607 based on the signal output from the delay circuit 610 . An amplitude component appears in the output of the power amplifier 607 by the control voltage from the amplitude modulation circuit 611 .

The phase modulation circuit 606 is, for example, a voltage-controlled oscillator or a frequency conversion circuit employed in the first to third embodiments described above. In addition, the amplitude modulation circuit 611 is, for example, the voltage-controlled DC converter employed in the first to third embodiments described above.

The distributor 612 distributes the output of the power amplifier 607 to the antenna 613 and the distortion detection circuit 614 . The antenna 613 transmits the signal distributed by the distributor 612 .

Distortion detection circuit 614 detects the amount of distortion of the signal from distributor 612 . The detection of the distortion amount is carried out by the following method: the method of calculating the level of the distortion frequency component by performing digital processing such as Fourier transform on the demodulated transmission signal; or after converting the frequency of the transmission signal into an analog baseband signal, the Distortion components are filtered to perform level detection, etc. The delay circuits 605 and 610 vary the amount of delay according to the control signal output from the distortion detection circuit 614 .

The distortion detection circuit 614 sets the delay amount so that the detected distortion amount is reduced. The amount of delay is set by changing the amount of delay within an appropriate range first, storing the relationship between the amount of delay and the amount of distortion, and selecting a method of providing the amount of delay that reduces distortion based on the stored data. Alternatively, it may be set by a method of sequentially changing the amount of delay while measuring the distortion, and searching for a point where the amount of distortion shows the minimum value.

The present transmission device has been described in which delay circuits are provided on both paths of the amplitude component and the phase component. However, if it is known in advance which path has a large amount of delay, the delay circuit may be inserted into only one of the two paths.

The present transmitting apparatus has been described in which delay circuits 605 and 610 are connected to the subsequent stages of filters 604 and 609 . However, it is also possible for the filters 604 , 609 to include the function of the delay circuits 605 , 610 .

The filters 604 and 609 operate as low-pass filters smoothing the outputs of the DA converters 603 and 608, so by changing the element values of the circuits constituting the low-pass filters, the delay amount of the signal passing through the band can also be changed.

Therefore, the present transmitting apparatus can reduce the distortion generated by the power amplifier and obtain high power efficiency by controlling the delay amount of the amplitude component or the phase component of the transmission signal so as to reduce the distortion amount of the transmission output.

Example 5

Fig. 5 is a block diagram of a transmission device according to a fifth embodiment of the present invention.

The arithmetic circuit 704 is composed of an amplitude calculation circuit 719 and a phase calculation circuit 720 . The amplitude calculation circuit 719 calculates the amplitude component of the input transmission baseband signal 701 . The phase calculation circuit 720 calculates the phase component of the input transmission baseband signal 701 . The switch 702 is composed of a linked switch 702A and a switch 702B.

The switch 702A switches and outputs the output of the amplitude calculation circuit 719 and the signal from the frequency-time-varying chirp signal source 703 . The switch 702B switches and outputs the output of the phase calculation circuit 720 and the signal from the chirp signal source 703 . DA converter 705 converts the output of switch 702B into an analog signal. The filter 706 passes a specific frequency among the output signals of the DA converter 705 .

The delay circuit 707 delays the output signal of the filter 706 . The carrier signal source 709 outputs a carrier signal with a constant frequency. The phase modulation circuit 708 mixes the output of the delay circuit 707 and the signal of the carrier signal source 709 to generate a phase modulation signal. Power amplifier 710 amplifies the output of phase modulation circuit 708 to a desired power level. DA converter 711 converts the output signal of switch 702A into an analog signal.

The filter 712 passes a specific frequency among the output signals of the DA converter 711 . The delay circuit 713 delays the output signal of the filter 712 . The amplitude modulation circuit 714 outputs a voltage for controlling the power amplifier 710 according to the output signal of the delay circuit 713 . The distributor 715 distributes the signal from the power amplifier 710 to the antenna 716 and the frequency conversion circuit 717 .

The antenna 716 transmits the signal from the splitter 715 . The frequency conversion circuit 717 converts the frequency of the signal from the distributor 715 from the signal of the carrier signal source 709 . The frequency component detection circuit 718 controls the delay amounts of the delay circuits 707 and 713 based on the output signal of the frequency conversion circuit 717 .

Next, the operation of the transmission device in the above configuration will be described.

In this transmission device, when adjusting the delay amount of the delay circuits 707 and 713, the input signals to the DA converters 705 and 711 are switched from the output signal from the arithmetic circuit 704 to the signal from the chirp signal source 703 through the switch 702. signal of. The chirp signal input to DA converter 705 passes through DA converter 705 , filter 706 and delay circuit 707 from switch 702B as a first chirp signal.

The phase modulation circuit 708 mixes the first chirp signal output from the delay circuit 707 and the carrier signal output from the carrier signal source 709 . Power amplifier 710 amplifies the output of phase modulation circuit 708 to a desired power level.

On the other hand, the chirp signal input to DA converter 711 passes through DA converter 711 , filter 712 and delay circuit 713 from switch 702A as a second chirp signal. The amplitude modulation circuit 714 controls the bias voltage of the power amplifier circuit 710 based on the second chirp signal output from the delay circuit 713 . As a result, the power amplifier 710 outputs a signal in which the first chirp signal and the second chirp signal are mixed.

The output signal of the power amplifier 710 is distributed by a distributor 715 , and a part of the signal is input to a frequency conversion circuit 717 . The frequency conversion circuit 717 mixes the sum signal from the divider 715 and the carrier signal from the carrier signal source 709 to obtain a signal having a frequency component of the difference between the first chirp signal and the second chirp signal.

The first chirp signal and the second chirp signal are mixed in the power amplifier 710. When there is no delay difference between the path of the amplitude component and the phase component, since signals of the same frequency are mixed, the output of the frequency conversion circuit 717 is A signal with only a DC component. On the other hand, when there is a delay difference between paths, the output of the frequency conversion circuit 717 appears as a signal having an AC component.

Therefore, the frequency component detection circuit 718 detects the AC component, that is, the frequency component, from the output signal of the frequency conversion circuit 717, and adjusts the delays of the delay circuits 707 and 713 so that it becomes only the DC component. timing control. In addition, frequency conversion circuit 717 also includes a frequency component of the sum of the first and second chirp signals, but this component is unnecessary and suppressed by a low-pass filter.

Therefore, this transmitting apparatus uses a chirp signal instead of transmitting a baseband signal, detects the frequency component of the down-converted signal from the output of the power amplifier, and adjusts the delay amount of the delay circuit so that the frequency component is only a DC component. The timing between the paths of the amplitude component and the phase component is made to match. As a result, it is possible to realize a transmission device with high power efficiency that reduces distortion generated by the power amplifier.

sixth embodiment

Fig. 6 is a block diagram of a transmission device according to a sixth embodiment of the present invention.

The arithmetic circuit 804 is composed of an amplitude calculation circuit 821 and a phase calculation circuit 822 . The amplitude calculation circuit 821 calculates the amplitude component of the input transmission baseband signal 801 . The phase calculation circuit 822 calculates the phase component of the input transmission baseband signal 801 .

The chirp signal conversion circuit 820 converts the signal from the fixed frequency signal source 805 which has no temporal frequency change, and outputs the signal of the chirp signal source 803 . The switch 802 is composed of a linked switch 802A and a switch 802B. The switch 802A switches and outputs the output of the amplitude calculation circuit 821 and the signal from the chirp signal source 803 .

The switch 802B switches and outputs the output of the phase calculation circuit 822 and the signal from the chirp conversion circuit 820 . DA converter 806 converts the output of switch 802B into an analog signal. The filter 807 passes specific frequencies among the output signals of the DA converter 806 . The carrier signal source 809 outputs a carrier signal with a constant frequency.

The phase modulation circuit 808 mixes the signal of the carrier signal source 809 with the output of the filter 807 to generate a phase modulation signal. The power amplifier 810 amplifies the power of the phase modulation circuit 808 to a desired power level. DA converter 811 converts the output signal of switch 802A into an analog signal. The filter 812 passes a specific frequency among the output signals of the DA converter 811 .

The delay circuit 813 delays the output signal of the filter 812 . The amplitude modulation circuit 814 outputs a voltage for controlling the power amplifier 810 according to the output signal of the delay circuit 813 . The distributor 815 distributes the signal from the power amplifier 810 to the antenna 816 and the frequency conversion circuit 817 . The antenna 816 transmits the signal from the splitter 815 .

The frequency conversion circuit 817 converts the frequency of the signal from the distributor 815 based on the signal from the carrier signal source 809 . The phase comparison circuit 818 compares the phase of the output signal of the frequency conversion circuit 817 with the phase of the fixed frequency signal source 805 . The control signal filter 819 controls phase synchronization between the phase comparison circuit 818 and the delay circuit 813 .

Next, the operation of the transmission device in the above configuration will be described.

The basic operation of the transmission device is the same as that of the transmission device of the fifth embodiment. This transmitting apparatus uses the first chirp signal generated by the chirp signal source 803 and the second chirp signal which is output by the chirp conversion circuit 820 after mixing the signal of the fixed frequency signal source 805 and the first chirp signal.

The first chirp signal is output from the DA converter 811 to the signal path of the amplitude component, and the second chirp signal is output from the DA converter 806 to the signal path of the phase component. Here, there is no delay difference between the two paths, and if the two signals are mixed at the same timing in the power amplifier 810 , the output of the frequency conversion circuit 817 is a signal of the same frequency as the fixed frequency signal source 805 .

The signal having the same frequency as the fixed frequency signal source 805 is a signal having the same frequency as the frequency difference between the first and second chirp signals. Therefore, the phase comparison circuit 818 compares the phase of the output signal of the frequency conversion circuit 817 with the phase of the output signal of the fixed frequency signal source 805, and adjusts the delay amount of the delay circuit 813 so that the phase difference is a constant value, that is, the frequency is the same, thereby , you can control the timing between the two paths.

The delay circuit 813 is constituted by using circuit elements whose element values vary with the voltage of a varactor diode or the like, so that the amount of delay can be controlled by the voltage. At the same time, the control signal filter 819 is set as a loop filter to control the phase comparison circuit 818 and the delay. The phase synchronous operation among the circuits 813 enables timing adjustment of the amplitude component and the phase component mixed in the power amplifier 810 by phase synchronous control.

The frequency difference between the first and second chirp signals output by the frequency conversion circuit 817 can also be brought into agreement with the frequency of the fixed frequency signal source 805 by the value of the signal path delay difference of the amplitude component and the phase component. However, it can be avoided by appropriately setting the frequency change of the chirp signal according to the estimated delay difference of the signal path.

In addition, the transmission device has been described with the case where the delay circuit 813 is provided on the path of the amplitude component. However, when the signal propagation time of the path of the phase component is fast, a delay circuit is provided on the path of the phase component.

Therefore, instead of transmitting the modulated signal, this transmission device uses two chirp signals with a constant frequency difference, phase synchronization control of the signal down-converted from the carrier frequency signal from the output of the power amplifier, and phase synchronization to make the above-mentioned frequency difference the same. By controlling the signal delay amount of the amplitude component or phase component of the transmitted modulation signal, in the power amplifier, the timing of the mixed amplitude component and phase component can be automatically matched, thereby reducing the distortion generated by the power amplifier and obtaining high performance. power efficiency.

As described above, the transmitting device of the present invention is configured to detect the distortion component of the output signal from the power amplifying device, and automatically control the control timing of the voltage of the power amplifying device to reduce the distortion component, so that the reduction can be realized at the same time. Distortion of transmitted signals and improvement of power efficiency of a power amplification device.

Claims (14)

1. a sending method is characterized in that: be the voltage-controlled sending method of carrying out power amplifier device according to the envelope amplitude that sends signal; To distribute to from the output signal of above-mentioned power amplifier device and send signal and feedback signal, calculate the distortion composition of above-mentioned transmission signal by above-mentioned feedback signal, the control of the voltage of the above-mentioned power amplifier device of control control automatically regularly so that described distortion composition reduce.

2. sending method according to claim 1 is characterized in that: above-mentioned distortion composition is the out-of-band power of above-mentioned transmission signal.

3. a dispensing device is characterized in that: have: control the 1st deferred mount regularly of adjusting the voltage of power controlling amplifying device; Be used to distribute and feed back the distributor of the output of above-mentioned power amplifier device; With, to utilize by the signal that above-mentioned distributor fed back and calculate the distortion composition that sends signal, the retardation of automatically adjusting above-mentioned the 1st deferred mount is so that the distortion adjusting device that above-mentioned distortion composition reduces.

4. dispensing device according to claim 3 is characterized in that: above-mentioned distortion composition is the out-of-band power of above-mentioned transmission signal.

5. dispensing device according to claim 4 is characterized in that: have:

Calculate the magnitude determinations device that sends the baseband signal amplitude;

Control the voltage-operated device of the bias voltage that offers above-mentioned power amplifier device according to the output of above-mentioned the 1st deferred mount;

The 2nd deferred mount of exporting to Yu postponing to above-mentioned transmission baseband signal;

With the output transform of above-mentioned the 2nd deferred mount is the 1st frequency-transposition arrangement of RF signal;

With the signal transformation of above-mentioned feedback is the 2nd frequency-transposition arrangement of baseband signal or IF signal; With

According to the output of above-mentioned distortion adjusting device, be adjusted at above-mentioned the 1st deferred mount and the 2nd deferred mount give with retardation so that the retardation calculation element that the out-of-band power that is calculated by above-mentioned distortion adjusting device reduces;

Above-mentioned the 1st deferred mount is exported to and postpone above-mentioned magnitude determinations device,

Above-mentioned voltage-operated device is controlled above-mentioned bias voltage according to the output of above-mentioned the 1st deferred mount,

Above-mentioned power amplifier device amplifies the output of above-mentioned the 1st frequency-transposition arrangement,

Above-mentioned distortion adjusting device calculates above-mentioned out-of-band power according to the output of above-mentioned the 2nd frequency-transposition arrangement.

6. dispensing device according to claim 5 is characterized in that: above-mentioned out-of-band power is an adjacent channel leakage power.

7. dispensing device according to claim 6 is characterized in that: when the output of above-mentioned distortion adjusting device surpasses the value of regulation, stop the action of this dispensing device.

8. dispensing device according to claim 5 is characterized in that: when the output of above-mentioned distortion adjusting device surpasses the value of regulation, stop the action of this dispensing device.

9. dispensing device according to claim 5 is characterized in that: have:

Calculate the phase calculation device of above-mentioned transmission baseband signal phase place; With

According to the output of above-mentioned the 2nd deferred mount, the voltage controlled oscillator of output phase modulation signal;

Above-mentioned the 2nd deferred mount is exported to and postpone above-mentioned phase calculation device,

Above-mentioned the 1st frequency-transposition arrangement is the RF signal with the output transform of above-mentioned voltage controlled oscillator.

10. dispensing device according to claim 9 is characterized in that: above-mentioned out-of-band power is an adjacent channel leakage power.

11. dispensing device according to claim 10 is characterized in that: when the output of above-mentioned distortion adjusting device surpasses the value of regulation, stop the action of this dispensing device.

12. dispensing device according to claim 9 is characterized in that: when the output of above-mentioned distortion adjusting device surpasses the value of regulation, stop the action of this dispensing device.

13. dispensing device according to claim 3 is characterized in that: have:

The voltage controlled oscillator of the carrier signal of phase modulated is carried out in generation by the phase component that sends baseband signal; With

Delay is transfused to the 3rd deferred mount to the signal of the above-mentioned phase component of above-mentioned voltage controlled oscillator;

Above-mentioned distortion adjusting device is adjusted the retardation of above-mentioned the 3rd deferred mount with above-mentioned the 1st deferred mount.

14. dispensing device according to claim 13 is characterized in that: the 1st filter of the signal that above-mentioned the 3rd deferred mount is the above-mentioned phase component of bandwidth constraints,

Above-mentioned the 1st deferred mount is the 2nd filter of the signal of the above-mentioned amplitude composition of bandwidth constraints,

Above-mentioned distortion adjusting device changes the characteristic of passing through of above-mentioned the 1st filter or the 2nd filter and comes the control lag amount.

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