CN203193574U - Power amplifier with digital pre-distortion compensation combination cancellation function - Google Patents
Power amplifier with digital pre-distortion compensation combination cancellation function Download PDFInfo
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- CN203193574U CN203193574U CN 201320116025 CN201320116025U CN203193574U CN 203193574 U CN203193574 U CN 203193574U CN 201320116025 CN201320116025 CN 201320116025 CN 201320116025 U CN201320116025 U CN 201320116025U CN 203193574 U CN203193574 U CN 203193574U
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Abstract
The utility model discloses a power amplifier with a digital pre-distortion compensation combination cancellation function. The power amplifier comprises a digital pre-distortion unit circuit, an intermediate-frequency circuit, a small signal amplifying circuit, a first power divider, a driving and amplifying circuit, a reference signal adjusting circuit, a last stage amplifying circuit, a first combiner, a feedback detecting circuit and a signal processing and controlling circuit. According to the power amplifier, due to the fact that the digital pre-distortion unit circuit is added, meanwhile, due to the fact that two ways of output of the last stage amplifying circuit of the power amplifier can generate self-cancellation, compared with a traditional digital pre-distortion and Doherty circuit, higher efficiency and better lineation can be obtained, and the efficiency of the power amplifying can achieve 45-52%. The power amplifier has the advantages of being good in linearity indicator, high in efficiency index and low in hardware cost. Meanwhile, power amplifying work is reliable and stable.
Description
Technical field
The utility model relates to power amplifier, relates in particular to a kind of with digital pre-distortion compensation and close the power amplifier that the road offsets function.
Background technology
Current digital pre-distortion technology is widely used at wireless communication base station system, yet digital pre-distortion is subjected to the restriction of power amplifier saturation power, just can obtain the better linearity compensation effect at the power amplifier rollback by the situation of enough values, the compensation of digital pre-distortion simultaneously also has certain restriction, the distortion that power amplifier can not be produced all compensation is returned, if therefore can on the basis of digital pre-distortion compensation, further improve compensation ability, make power amplifier at rollback still less, be to be worth the problem discussed less than also obtaining better linearity under the condition of signal peak-to-average ratio particularly, the rollback of power amplifier more look younger concerning the efficient that can obtain just more high.
Summary of the invention
The purpose of this utility model is to provide a kind of and compensates and close the power amplifier that the road offsets function with digital pre-distortion, and this amplifier can be realized the high efficiency of the radiofrequency signal of mobile communication frequency range and high linear the amplification.
The utility model for realizing the technical scheme that the utility model purpose adopts is:
Provide a kind of with digital pre-distortion compensation and close the power amplifier that the road offsets function, comprise the intermediate-frequency circuit, small signal amplification circuit, first power splitter that connect successively, drive amplifying circuit, final stage amplifying circuit and mixer, wherein:
This power amplifier also comprises the reference signal regulating circuit, an input of described reference signal regulating circuit connects an output of described first power splitter, the output of described reference signal regulating circuit connects an input of described final stage amplifying circuit, and described final stage amplifying circuit comprises the multichannel final amplifier; Described final stage amplifying circuit is coupled out a part of signal from road final amplifier wherein, the undistorted signal of this part signal and described reference signal regulating circuit output subtracted each other obtain error signal, again error signal is carried out being injected into behind amplitude modulation and the phase modulation other final amplifier, the output of each road final amplifier is connected with described mixer, and the place carries out cancelling out each other of error signal at described mixer;
This power amplifier also comprises digital pre-distortion element circuit, feedback sense circuit and signal processing and control circuit;
The input of described digital pre-distortion element circuit inserts main signal, and an output of described digital pre-distortion element circuit connects the input of described intermediate-frequency circuit;
The input of described feedback sense circuit is connected with an output of described mixer, the signal that the output of described mixer is coupled out converts base band data to, and the output of described feedback sense circuit connects another input of described digital pre-distortion element circuit;
Described digital pre-distortion element circuit is according to the distortion of the calculated signals power amplifier of described feedback sense circuit output, and generation reverse distortion signal;
Described signal is handled and is connected with an output of described digital pre-distortion element circuit with the input of control circuit, described signal is handled and is connected with another input of described reference signal regulating circuit with an output of control circuit, and described signal is handled and is connected with another input of described final stage amplifying circuit with another output of control circuit.
Band digital pre-distortion described in the utility model compensation and closing in the power amplifier that the road offsets function, this power amplifier also comprises the peak clipping element circuit, the input of described peak clipping element circuit connects main signal, the peak-to-average force ratio of main signal is cut drop to below the preset value; An input of described digital pre-distortion element circuit connects the output of described peak clipping element circuit, by the main signal of described digital pre-distortion element circuit access through peak clipping.
Band digital pre-distortion described in the utility model compensation and closing in the power amplifier that the road offsets function, the error signal amplitude equal phase in the signal of two inputs of described mixer is opposite.
Band digital pre-distortion described in the utility model compensation and closing in the power amplifier that the road offsets function, the phase place of the main signal of two inputs of described mixer is identical, and the ratio of amplitude is 1:1 or 1:N.
The beneficial effect that the utility model produces is: power amplifier of the present utility model is owing to increased the digital pre-distortion element circuit, the two-way of final stage amplifying circuit output simultaneously can produce offseting certainly of error signal, add the Doherty circuit with respect to traditional digital pre-distortion and can access higher efficient and better linear, the efficient of power amplifier can reach 45-52%, of the present utility modelly possess simultaneously that linear index is good, efficiency index is high, realize the low advantage of hardware cost, can accomplish power amplifier reliable operation, stable simultaneously again.
Description of drawings
The utility model is described in further detail below in conjunction with drawings and Examples, in the accompanying drawing:
Fig. 1 is the compensation of the utility model embodiment band digital pre-distortion and closes the power amplifier circuit theory diagram that the road offsets function;
Fig. 2 is the structural representation one of final stage amplifying circuit among the utility model embodiment;
Fig. 3 is the structural representation two of final stage amplifying circuit among the utility model embodiment;
Fig. 4 is the structural representation one of final stage time-delay and amplifying circuit among the utility model embodiment;
Fig. 5 is the structural representation two of final stage time-delay and amplifying circuit among the utility model embodiment;
Fig. 6 is the structural representation of the utility model embodiment reference signal regulating circuit;
Fig. 7 is the structural representation one of final amplifier among the utility model embodiment;
Fig. 8 is the structural representation two of final amplifier among the utility model embodiment;
Fig. 9 is the structural representation three of final amplifier among the utility model embodiment.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explaining the utility model, and be not used in restriction the utility model.
As shown in Figure 1, the utility model embodiment band digital pre-distortion compensates and closes the power amplifier that the road offsets function, comprises the intermediate-frequency circuit 3, small signal amplification circuit 4, first power splitter 5, driving amplifying circuit 6, final stage amplifying circuit 8 and the mixer 9 that connect successively.Be the input A7 of the output terminals A 6 connection small signal amplification circuits 4 of intermediate-frequency circuit 3, the output terminals A 8 of small signal amplification circuit 4 connects the input A9 of first power splitter 5; One output terminals A 10 of first power splitter 5 connects the input A11 that drives amplifying circuit 6, and the output terminals A 12 that drives amplifying circuit 6 connects the main signal input A13 of final stage amplifying circuit 8;
This power amplifier also comprises reference signal regulating circuit 7, an input B2 of reference signal regulating circuit 7 connects an output B1 of first power splitter 5, and the output B4 of reference signal regulating circuit 7 is connected to the reference signal input B5 of final stage amplifying circuit 8.Final stage amplifying circuit 8 comprises the multichannel final amplifier; Final stage amplifying circuit 8 is coupled out a part of signal from road final amplifier wherein, the undistorted signal of this part signal and reference signal regulating circuit 7 outputs subtracted each other obtain error signal, again error signal is carried out being injected into behind amplitude modulation and the phase modulation other final amplifier, the output of each road final amplifier is connected with mixer 9, and 9 places carry out cancelling out each other of error signal at mixer.
This power amplifier also comprises digital pre-distortion element circuit 2, feedback sense circuit 10 and signal processing and control circuit 11;
The input A3 of digital pre-distortion element circuit 2 inserts main signal, and an output terminals A 4 of digital pre-distortion element circuit 2 connects the input A5 of intermediate-frequency circuit 3;
The input C8 of feedback sense circuit 10 is connected with an output of mixer 9, and the signal that the output of mixer 9 is coupled out converts base band data to, and the output of feedback sense circuit 10 connects another input of digital predistortion unit circuit 2;
Digital pre-distortion element circuit 2 is according to the distortion of the calculated signals power amplifier of feedback sense circuit 10 output C7 output, and generation reverse distortion signal;
Signal is handled and is connected with an output C1 (being control end) of digital pre-distortion element circuit 2 with the input C3 of control circuit 11, signal is handled and is connected with another input B3 of reference signal regulating circuit 7 with an output C4 of control circuit 11, and signal is handled and is connected with another input C6 (being control end) of final stage amplifying circuit 8 with another output C5 of control circuit 11.
Among the embodiment of the present utility model, this power amplifier also comprises peak clipping element circuit 1, and the input A1 of peak clipping element circuit 1 connects main signal, the peak-to-average force ratio of main signal is cut drop to below the preset value, to improve power amplification efficiency; An input A3 of digital pre-distortion element circuit 2 connects the output terminals A 2 of peak clipping element circuit 1, by the main signal of peak clipping element circuit 1 access through peak clipping.
In order to realize the elimination of error signal, the error signal amplitude equal phase in the signal of 9 two inputs of mixer is opposite.
Among the utility model embodiment, the phase place of the main signal of 9 two inputs of mixer is identical, and the ratio of amplitude is 1:1 or 1:N.
Working method of the present utility model is, the radiofrequency signal that is exaggerated is that main signal is input to peak clipping element circuit 1, the peak clipping that peak clipping element circuit 1 is realized signal, how many concrete peak clippings decided according to practical situations to, be admitted to digital pre-distortion element circuit 2 after the signal peak clipping and carry out digital pre-distortion, converted to analog signal and be mixed to radio circuit by intermediate-frequency circuit 3 then, amplified by small signal amplification circuit 4, be input to first power splitter 5 then, first power splitter 5 is divided into two-way with the signal that is exaggerated, wherein one road signal enters the amplifying circuit of back, another road signal is as there not being the clean signal of distortion to be input to reference signal regulating circuit 7, the output that drives amplifying circuit 6 is connected to final stage amplifying circuit 8, reference signal through 7 outputs of reference signal regulating circuit also is input to final stage amplifying circuit 8, final stage amplifying circuit 8 is made of N road final amplifier, wherein N is more than or equal to 2, error signal in the final two-way output signal of final stage amplifying circuit 8 is closed the road at mixer 9 places and is offseted, and closes the two-way error signal that the road offsets and has the advantages that the amplitude equal phase differs 180 °.The signal sampling that feedback sense circuit 10 will be come from mixer 9 outputs couplings is to base band, and baseband signal is input to digital pre-distortion element circuit 2, carry out the calculating of pre-distortion coefficients by digital pre-distortion element circuit 2, adjust pre-distortion coefficients according to result of calculation, make power amplifier obtain better linearity.This power amplifier has carried out under the condition that has offseted and obtained better linearity certainly of error signal at the final stage amplifying circuit, carry out the secondary linearisation by 2 pairs of these power amplifiers of digital pre-distortion element circuit again, thereby twice linearizing result superposes and makes this power amplifier obtain the favorable linearity effect.
As shown in Figure 2, be the theory diagram one of the final stage amplifying circuit 8 of the utility model embodiment, it is undertaken offseting for twice by three tunnel final stage amplifying circuits, to eliminate error signal better.Final stage amplifying circuit 8 comprises: second power splitter 15, first final amplifier 16, first coupler, 17, the first delayers 18, subtracter 19, the 3rd power splitter 20, the first error signal regulating circuit, 21, the second error signal regulating circuits, 22, the four power splitters 23, the time-delay of first final stage and the time-delay of amplifying circuit 25, the second final stages and amplifying circuit 24 and first mixer 26.The undistorted main signal through amplitude modulation and phase modulation of output is input in the subtracter 19 to subtract each other with output signal from first coupler 17 and obtains error signal from reference signal regulating circuit 7, and output signal contains error signal and main signal from first coupler 17.The signal processing can control the first error signal regulating circuit 21 with the output signal of control circuit 11 and the second error signal regulating circuit 22 carries out amplitude modulation and phase modulation.Carry out amplitude modulation and phase modulation respectively and be input to the time-delay of first final stage and amplifying circuit 25 through the first error signal regulating circuit 21 and the second error signal regulating circuit 22 from the two-way error signal of the 3rd power splitter 20 outputs, in the time-delay of second final stage and the amplifying circuit 24, the signal of first final amplifier, 16 outputs and the time-delay of second final stage are carried out the counteracting first time of error signal with the signal of amplifying circuit 24 outputs at first mixer, 26 places.Signal after offsetting the first time carries out the counteracting second time of error signal at mixer 9 places and the time-delay of first final stage with the signal of amplifying circuit 25 outputs again.
As shown in Figure 3, be the theory diagram two of the final stage amplifying circuit 8 of the utility model embodiment, it once offsets by two-way final stage amplifying circuit, to eliminate error signal.Final stage amplifying circuit 8 comprises second power splitter 27, first final amplifier 28, coupler 29, delayer 30, subtracter 31, error signal regulating circuit 32 and final stage time-delay and amplifying circuit 33 among this embodiment.The signal of exporting from the output of second power splitter 27 amplifies at first final amplifier 28, can produce distorted signal simultaneously, the signal that is exaggerated and distorted signal output to the input of coupler 29 from the output of first final amplifier 28, output to an input of subtracter 31 then from the coupled end of coupler 29, subtract each other with the undistorted main signal through amplitude modulation and phase modulation that from reference signal regulating circuit 7, outputs to subtracter 31 and obtain error signal; Error signal regulating circuit 32 is handled with signal and is connected with the output C5 of control circuit 11, the error signal of 32 pairs of subtracters of error signal regulating circuit, 31 outputs is carried out the adjusting of amplitude and phase place under its control, output to the coupled end of final stage time-delay and amplifying circuit 33 then, output to the input B7 of mixer 9 again after final stage time-delay and amplifying circuit 33 are delayed time and amplified, the signal of exporting with delayer 30 carries out the counteracting of error signal.
First final stage time-delay and amplifying circuit 25, the time-delay of second final stage and amplifying circuit 24 and final stage time-delay and amplifying circuit 33 concrete structures comprise second delayer 34, second final amplifier 35 and second coupler 36 as shown in Figure 4 and Figure 5.It has two kinds of implementations, wherein, one of implementation as shown in Figure 4, the output of second coupler 36 connects the input of second final amplifier 35, the output of second final amplifier 35 connects the input of second delayer 34.Implementation two as shown in Figure 5, the output of second delayer 34 connects the input of second final amplifier 35, the output of second final amplifier 35 connects the input of second coupler 36.
Be illustrated in figure 6 as the theory diagram of the reference signal regulating circuit 7 in the utility model, reference signal regulating circuit 7 comprises first amplitude modulator, first phase modulator, the 4th delay line and first prime amplifier.
The input that is input to first amplitude modulator from the main signal of the output B1 of first power splitter 5 output carries out amplitude modulation, the output of first amplitude modulator is connected to the input of first phase modulator, first phase modulator carries out phase modulation to the signal of input, the output of first phase modulator is connected to the input of the 4th delay line, the 3rd delay line carries out time delay to the signal of input, the output of the 3rd delay line is connected to the input of first prime amplifier, first prime amplifier amplifies the signal of input, and exports the signal that is exaggerated by output.Wherein signal is handled with the output signal of control circuit 11 and is controlled first amplitude modulator and first phase modulator.
Shown in Fig. 7,8,9, it is the structural representation of three kinds of embodiment of first final amplifier 16, second final amplifier 28 or the 3rd final amplifier 35.Among Fig. 7, first final amplifier 16, second final amplifier 28 or the 3rd final amplifier 35 comprise two amplifiers in parallel, and an end of its parallel connection connects power splitter, and the other end connects mixer; Among Fig. 8, three amplifiers of first final amplifier 16, second final amplifier 28 or 35 parallel connections of the 3rd final amplifier, an end of its parallel connection connects power splitter, and the other end connects mixer; Among Fig. 9, first final amplifier 16, second final amplifier 28 or the 3rd final amplifier 35 comprise four amplifiers in parallel, and an end of its parallel connection connects power splitter, and the other end connects mixer.Be understandable that to comprise N amplifier in parallel in first final amplifier 16, second final amplifier 28 or the 3rd final amplifier 35, N is natural number.
The utility model is that the power amplifier overall efficiency can reach more than the 45-52% under the condition of 10dB at the input signal peak-to-average force ratio, adaptivity is good simultaneously, under all temps condition, can keep good efficiency and linearity, concrete efficient is relevant with the power output of the peak-to-average force ratio that is exaggerated signal and power amplifier, owing to increased and offseted function, same power amplifier is amplifying under the identical signal conditioning, and rollback needs still less, thereby can obtain better efficient.Power amplifier is 40MHz at effective bandwidth of operation, and the carrier wave of signal can dispose arbitrarily in the 20MHz bandwidth of operation, for high linear amplification of maximum 12 carrier waves of GSM signal, IM3 under this condition (third order intermodulation) can reach-and more than the 65dBc.The utility model can be widely used in arrowband base stations in mobile communication system power amplifier.
Should be understood that, for those of ordinary skills, can be improved according to the above description or conversion, and all these improvement and conversion all should belong to the protection range of the utility model claims.
Claims (2)
1. one kind with digital pre-distortion compensation and close the power amplifier that the road offsets function, comprise the intermediate-frequency circuit (3), small signal amplification circuit (4), first power splitter (5), driving amplifying circuit (6), final stage amplifying circuit (8) and the mixer (9) that connect successively, it is characterized in that:
This power amplifier also comprises reference signal regulating circuit (7), an input of described reference signal regulating circuit (7) connects an output of described first power splitter (5), the output of described reference signal regulating circuit (7) connects an input of described final stage amplifying circuit (8), and described final stage amplifying circuit (8) comprises the multichannel final amplifier; Described final stage amplifying circuit (8) is coupled out a part of signal from road final amplifier wherein, should part signal and the undistorted signal of described reference signal regulating circuit (7) output subtract each other and obtain error signal, again error signal is carried out being injected into behind amplitude modulation and the phase modulation other final amplifier, the output of each road final amplifier is connected with described mixer (9), locates to carry out cancelling out each other of error signal at described mixer (9);
This power amplifier also comprises digital pre-distortion element circuit (2), feedback sense circuit (10) and signal processing and control circuit (11);
The input of described digital pre-distortion element circuit (2) inserts main signal, and an output of described digital pre-distortion element circuit (2) connects the input of described intermediate-frequency circuit (3);
The input of described feedback sense circuit (10) is connected with an output of described mixer (9), the signal that the output of described mixer (9) is coupled out converts base band data to, and the output of described feedback sense circuit (10) connects another input of described digital pre-distortion element circuit (2);
Described digital pre-distortion element circuit (2) is according to the distortion of the calculated signals power amplifier of described feedback sense circuit (10) output, and generation reverse distortion signal;
Described signal is handled and is connected with an output of described digital pre-distortion element circuit (2) with the input of control circuit (11), described signal is handled and is connected with another input of described reference signal regulating circuit (7) with an output of control circuit (11), and described signal is handled and is connected with another input of described final stage amplifying circuit (8) with another output of control circuit (11).
2. band digital pre-distortion according to claim 1 compensates and closes the power amplifier that the road offsets function, it is characterized in that, this power amplifier also comprises peak clipping element circuit (1), the input of described peak clipping element circuit (1) connects main signal, the peak-to-average force ratio of main signal is cut drop to below the preset value; An input of described digital pre-distortion element circuit (2) connects the output of described peak clipping element circuit (1), by the main signal of described digital pre-distortion element circuit (2) access through peak clipping.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320116025 CN203193574U (en) | 2013-03-14 | 2013-03-14 | Power amplifier with digital pre-distortion compensation combination cancellation function |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320116025 CN203193574U (en) | 2013-03-14 | 2013-03-14 | Power amplifier with digital pre-distortion compensation combination cancellation function |
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| CN203193574U true CN203193574U (en) | 2013-09-11 |
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| CN 201320116025 Withdrawn - After Issue CN203193574U (en) | 2013-03-14 | 2013-03-14 | Power amplifier with digital pre-distortion compensation combination cancellation function |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103219957A (en) * | 2013-03-14 | 2013-07-24 | 武汉正维电子技术有限公司 | Power amplifier with digital predistortion compensation and combiner offset function |
-
2013
- 2013-03-14 CN CN 201320116025 patent/CN203193574U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103219957A (en) * | 2013-03-14 | 2013-07-24 | 武汉正维电子技术有限公司 | Power amplifier with digital predistortion compensation and combiner offset function |
| CN103219957B (en) * | 2013-03-14 | 2016-08-10 | 武汉正维电子技术有限公司 | With digital predistortion compensation and the power amplifier of combiner offset function |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20130911 Effective date of abandoning: 20160810 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |