阅读说明：本技术 一种功放发射机 (Power amplifier transmitter ) 是由 彭瑞敏 丁冲 张晓毅 王晖 秦天银 于 2020-06-03 设计创作，主要内容包括：本发明公开一种功放发射机,包括Outphasing信号分离电路、Doherty信号分离电路、第一加法器、第二加法器和功率放大电路,Outphasing信号分离电路对第一基带信号进行信号分离处理,并输出异相的第一路Outphasing分离信号和第二路Outphasing分离信号,Doherty信号分离电路对第二基带信号进行信号分离处理,并输出第一路Doherty分离信号和基于Doherty时域调整的第二路Doherty分离信号,第一加法器将第一路Outphasing分离信号和第一路Doherty分离信号相加,第二加法器将第二路Outphasing分离信号和第二路Doherty分离信号相加,并输入到功率放大电路进行功率放大,相对于现有的双输入工作模式架构,本发明无需在不同频点上满足同一种阻抗趋势,而是有两种不同的功放工作模式对应的阻抗趋势可选,简化电路结构,降低功放发射机的设计难度。(The invention discloses a power amplifier transmitter, which comprises an Outphasings signal separating circuit, a Doherty signal separating circuit, a first adder, a second adder and a power amplifying circuit, wherein the Outphasings signal separating circuit is used for carrying out signal separation processing on a first baseband signal and outputting a first path of Outphasings separating signal and a second path of Outphasings separating signal which are out of phase, the Doherty signal separating circuit is used for carrying out signal separation processing on a second baseband signal and outputting a first path of Doherty separating signal and a second path of Doherty separating signal which is adjusted based on a Doherty time domain, the first adder is used for adding the first path of Outphasings separating signal and the first path of Doherty separating signal, the second adder is used for adding the second path of Outphasings separating signal and the second path of Doherty separating signal and inputting the signals to the power amplifying circuit for power amplification, compared with the traditional double-input working mode framework, the power amplifier transmitter does not need to meet the same impedance trend on different frequency points, but has two selectable impedance trends corresponding to the two different power amplifying working modes, the circuit structure is simplified, and the design difficulty of the power amplifier transmitter is reduced.)

1. A power amplifier transmitter, comprising:

a first input terminal for inputting a first baseband signal;

a second input terminal for inputting a second baseband signal;

an Outphasing signal separation circuit, configured to connect the first input terminal to perform signal separation processing on the first baseband signal, and output a first Outphasing separation signal and a second Outphasing separation signal;

the Doherty signal separating circuit is used for being connected with the second input end to perform signal separation processing on the second baseband signal and outputting a first path of Doherty separating signal and a second path of Doherty separating signal based on Doherty time domain adjustment;

a first adder, configured to add the first outgoing separated signal and the first Doherty separated signal;

a second adder, configured to add the second outgoing separated signal and the second Doherty separated signal; and

and the power amplification circuit is used for supporting an outbound working mode in the frequency band of the first baseband signal and supporting a Doherty working mode in the frequency band of the second baseband signal, and is connected with the output ends of the first adder and the second adder so as to perform power amplification on the signals output by the first adder and the second adder.

2. The power amplifier transmitter of claim 1, wherein the power amplifier circuit comprises a first amplifier, a second amplifier and a third adder, wherein an input terminal of the first amplifier is connected to an output terminal of the first adder, an input terminal of the second amplifier is connected to an output terminal of the second adder, and output terminals of the first amplifier and the second amplifier are connected to an input terminal of the third adder.

3. The power amplifier transmitter of claim 1, further comprising:

the first digital predistortion unit is used for being connected with the first input end to carry out digital predistortion processing on the first baseband signal and then inputting the first baseband signal to the Outphasing signal separation circuit;

the second digital predistortion unit is connected with the second input end to perform digital predistortion processing on the second baseband signal and then input the second baseband signal to the Doherty signal separation circuit;

the output end of the first adder is connected to the power amplification circuit through the first digital-to-analog conversion unit; and

and the output end of the second adder is connected to the power amplification circuit through the second digital-to-analog conversion unit.

4. The power amplifier transmitter of claim 3, wherein the first digital predistortion unit is further configured to connect to the second input terminal to perform digital predistortion on the first baseband signal and the second baseband signal at the same time, and the second digital predistortion unit is further configured to connect to the first input terminal to perform digital predistortion on the first baseband signal and the second baseband signal at the same time.

5. The power amplifier transmitter of claim 1, wherein the Outphasing signal separation circuit comprises:

the first modulus taking unit is used for connecting the first input end and performing modulus taking processing on the first baseband signal;

the second modulus taking unit is used for connecting the second input end and performing modulus taking processing on the second baseband signal;

a first lookup table unit, storing first Outphasing information, the first lookup table unit being configured to connect the first modulo unit and the second modulo unit, and output a first Outphasing phase angle according to the first Outphasing information, a modulus value of the first baseband signal, and a modulus value of the second baseband signal;

a second lookup table unit, storing second Outphasing information, configured to connect the first modulo unit and the second modulo unit, and output a second Outphasing phase angle according to the second Outphasing information, a modulus value of the first baseband signal, and a modulus value of the second baseband signal;

a first multiplier, configured to connect the first input terminal and an output terminal of the first lookup table unit, multiply the first baseband signal by phase information represented by the first outgoing phase angle, and output the first outgoing separated signal; and

and the second multiplier is used for connecting the first input end and the output end of the second lookup table unit, multiplying the first baseband signal by the phase information represented by the second out-phasing phase angle and outputting the second out-phasing separation signal.

6. The power amplifier transmitter of claim 5, wherein the Outphasing signal separation circuit further comprises a first digital up-conversion unit and a second digital up-conversion unit, the first multiplier, the first digital up-conversion unit and the first adder are sequentially connected, and the second multiplier, the second digital up-conversion unit and the second adder are sequentially connected.

7. The power amplifier transmitter of claim 5, wherein the first lookup table unit and the second lookup table unit each store therein a two-dimensional lookup table (2D-LUT).

8. The power amplifier transmitter of claim 1, wherein the Doherty signal separating circuit further comprises a signal adjusting unit, the signal adjusting unit is configured to perform one or more adjustments of gain, phase and waveform on the second baseband signal, and the second baseband signal is processed by the signal adjusting unit to obtain the second Doherty separated signal.

9. The power amplifier transmitter of claim 8, wherein the Doherty signal separating circuit further comprises a third digital up-conversion unit and a fourth digital up-conversion unit, the second baseband signal is processed by the third digital up-conversion unit and then input to the first adder, and the second baseband signal is processed by the signal conditioning unit and processed by the fourth digital up-conversion unit and then input to the second adder.

10. The power amplifier transmitter of claim 1, wherein the first baseband signal comprises a plurality of first baseband signals with different frequency bands, the second baseband signal comprises a plurality of second baseband signals with different frequency bands, the number of Outphasing signal separation circuits is the same as that of the first baseband signals, and the number of Doherty signal separation circuits is the same as that of the second baseband signals.

Technical Field

The invention relates to the technical field of communication, in particular to a power amplifier transmitter.

Background

With the development of communication technology, the requirement for the efficiency index of a radio frequency Power Amplifier (PA) in the transmitter architecture of a communication base station is gradually increased, and the mode of supporting multiple carriers is already commonly applied in a communication network, so that the Power Amplifier, as the most important energy consuming device in the communication base station, needs to support signals of two or more frequency bands at the same time.

The existing dual-input power amplifier applies the same dual-input working mode in a broadband multi-frequency scene, so that the output matching circuit is required to meet the same impedance trend at different frequency points, and the design complexity of the matching circuit of the power amplifier is increased.

Disclosure of Invention

The embodiment of the invention mainly aims to provide a power amplifier transmitter, aiming at simplifying the structure of a matching circuit of a power amplifier and reducing the design difficulty of the power amplifier transmitter.

In order to achieve the above object, an embodiment of the present invention provides a power amplifier transmitter, including:

a first input terminal for inputting a first baseband signal;

a second input terminal for inputting a second baseband signal;

an Outphasing signal separation circuit, configured to connect the first input terminal to perform signal separation processing on the first baseband signal, and output a first Outphasing separation signal and a second Outphasing separation signal;

the Doherty signal separating circuit is used for being connected with the second input end to perform signal separation processing on the second baseband signal and outputting a first path of Doherty separating signal and a second path of Doherty separating signal based on Doherty time domain adjustment;

a first adder, configured to add the first outgoing separated signal and the first Doherty separated signal;

a second adder, configured to add the second outgoing separated signal and the second Doherty separated signal; and

and the power amplification circuit is used for supporting an outbound working mode in the frequency band of the first baseband signal and supporting a Doherty working mode in the frequency band of the second baseband signal, and is connected with the output ends of the first adder and the second adder so as to perform power amplification on the signals output by the first adder and the second adder.

The power amplifier transmitter provided by the embodiment of the invention is provided with an Outphasingsignal separation circuit for carrying out-of-phase signal separation processing on a first baseband signal to obtain a first Outphasingsignal and a second Outphasingsignal, a Doherty signal separation circuit for carrying out digital Doherty signal separation processing on a second baseband signal to obtain a first Doherty signal and a second Doherty signal, two paths of signals input to a power amplification circuit are obtained by adding the first Outphasingsignal and the first Doherty signal and adding the second Outphasingsignal and the second Doherty signal, the power amplification circuit outputs amplified radio-frequency signals in a combined way after frequency mixing processing, and compared with the traditional double-input working mode architecture, the power amplifier transmitter provided by the embodiment of the invention has two selectable impedance trends without meeting the same impedance trend on different trends, but has two selectable impedance trends corresponding to different power amplifier working modes, the circuit structure is simplified, and the design difficulty of the power amplifier transmitter is reduced.

Drawings

Fig. 1 is a circuit diagram of a dual-frequency concurrent input power amplifier transmitter according to an embodiment of the present invention;

fig. 2 is a circuit diagram of a power amplifier circuit according to an embodiment of the invention;

fig. 3 is a circuit diagram of a multi-frequency concurrent input power amplifier transmitter according to a second embodiment of the present invention;

fig. 4 is a circuit diagram of a power amplifier circuit according to a second embodiment of the present invention.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the following description, suffixes such as "module", "part", or "unit" used to denote elements are used only for facilitating the explanation of the present invention, and have no peculiar meaning in itself. Thus, "module", "component" or "unit" may be used mixedly.

Example one

As shown in fig. 1, the present embodiment provides a power amplifier transmitter, which includes

A first input terminal for inputting a first baseband signal;

a second input terminal for inputting a second baseband signal;

an Outphasing signal separation circuit 100, configured to connect to a first input end to perform signal separation processing on a first baseband signal, and output a first Outphasing separation signal and a second Outphasing separation signal;

a Doherty signal separating circuit 200, configured to be connected to the second input terminal to perform signal separation processing on the second baseband signal, and output a first path of Doherty separating signal and a second path of Doherty separating signal based on Doherty time domain adjustment;

a first adder 300, configured to add the first outgoing separated signal and the first Doherty separated signal;

a second adder 400, configured to add the second outgoing separated signal and the second Doherty separated signal; and

the power amplification circuit 500 is configured to support an Outphasing operation mode in a frequency band of the first baseband signal and support a Doherty operation mode in a frequency band of the second baseband signal, and the power amplification circuit 500 is connected to output ends of the first adder 300 and the second adder 400, so as to perform power amplification on signals output by the first adder 300 and the second adder 400.

In this embodiment, a description is given by taking a first baseband signal as Band1 and a second baseband signal as Band2 as an example, where a frequency Band of the first baseband signal Band1 and a frequency Band of the second baseband signal Band2 are different from each other, so that the power amplifier transmitter of this embodiment is a dual-frequency dual-input amplifier circuit, and can support an out phase operating mode in the frequency Band of Band1 and a Doherty operating mode in the frequency Band2, and therefore, the first baseband signal Band1 and the second baseband signal Band2 are amplified in the power amplifier circuit 500 in the out phase operating mode and the Doherty operating mode, respectively, and then are combined and output.

Based on this, an Outphasing signal separation circuit 100 and a Doherty signal separation circuit 200 which are matched are provided for the power amplification circuit 500, wherein Outphasing information corresponding to Band1 is stored in the Outphasing signal separation circuit 100, a first baseband signal Band1 outputs a first Outphasing separation signal and a second Outphasing separation signal after phase angle transformation in the Outphasing signal separation circuit 100, the Doherty signal separation circuit 200 is also divided into two paths to output, one path is directly output as a first Doherty separation signal, the other path outputs a second Doherty separation signal after being adjusted based on a Doherty time domain, the first Outphasing separation signal and the first Doherty separation signal are added through a first adder 300, and the second Outphasing separation signal and the second Doherty separation signal are added through a second adder 400 to obtain two paths of input of the power amplification circuit 500 respectively. Because the two paths of input of the power amplification circuit 500 work in different working modes, the same impedance trend is not required to be met at different frequency points, but the impedance trends corresponding to two different power amplification working modes are selectable, so that the circuit structure is simplified, and the circuit design difficulty and the circuit debugging complexity are reduced.

It can be understood that the first baseband signal Band1 and the second baseband signal Band2 which are concurrently input at double frequencies are frequency-divided at a digital end, for example, in an FPGA device, an input frequency is divided into two frequency bands based on an out-phasing operation mode and a Doherty operation mode supported by the power amplification circuit 500, and the power amplification performance of the conventional single-input Doherty is improved by using the out-phasing and double-input Doherty high efficiency characteristics.

Referring to fig. 2, to implement a dual-input combined output, the power amplification circuit 500 includes a third adder 510, a first amplifier PA1, and a second amplifier PA2, an input terminal of the first amplifier PA1 is connected to an output terminal of the first adder 300, an input terminal of the second amplifier PA2 is connected to an output terminal of the second adder 400, and output terminals of the first amplifier PA1 and the second amplifier PA2 are connected to an input terminal of the third adder 510. The power amplification circuit 500 is a dual-input dual-band power amplifier, and has a single-input single-output first amplifier PA1 and a single-output second amplifier PA2 built therein, and the two outputs of the first amplifier PA1 and the second amplifier PA2 are added by a third adder 510, so that power amplification of a dual-frequency concurrent input signal is realized.

In order to improve the efficiency of the power amplifier circuit 500 and reduce the distortion generated when the power amplifier circuit 500 operates in its non-linear region, the present embodiment employs digital predistortion to perform linearization processing on the first baseband signal Band1 and the second baseband signal Band2, and specifically, the power amplifier transmitter further includes:

a first digital predistortion unit DPD1, configured to be connected to the first input terminal to perform digital predistortion processing on the first baseband signal Band1 and input the processed signal to the Outphasing signal separation circuit 100;

a second digital predistortion unit DPD2, connected to the second input terminal, for performing digital predistortion on the second baseband signal Band2 and inputting the second baseband signal Band2 to the Doherty signal splitting circuit 200;

the first digital-to-analog conversion unit DAC1, the output terminal of the first adder 300 is connected to the power amplification circuit 500 through the first digital-to-analog conversion unit DAC 1; and

the output terminal of the second adder 400 is connected to the power amplifying circuit 500 through a second digital-to-analog converting unit DAC2, the second digital-to-analog converting unit DAC 2.

The baseband signal is digitized based on the digital predistortion technology, and the digital-analog signal conversion is performed at the output end to adapt to the working mode of the power amplifying circuit 500, so that the linearity of the whole system architecture is improved, and the efficiency of the power amplifying circuit 500 is improved.

In order to reduce the influence of the second baseband signal Band2 on the linearity of the first baseband signal Band1, the first digital predistortion unit DPD1 introduces the second baseband signal Band2 as an input on the basis of performing digital predistortion processing on the first baseband signal Band1, and similarly, the second digital predistortion unit DPD2 introduces the first baseband signal Band1 as an input on the basis of performing digital predistortion processing on the second baseband signal Band2 to reduce the influence of the first baseband signal Band1 on the linearity of the second baseband signal Band2, it is understood that in this embodiment, the output of the first digital predistortion unit DPD1 is a signal after the predistortion processing of the first baseband signal Band1, and the output of the second digital predistortion unit DPD2 is a signal after the predistortion processing of the second baseband signal Band 2. Obviously, for the two frequency bands of the first baseband signal Band1 and the second baseband signal Band2, the first digital predistortion unit DPD1 and the second digital predistortion unit DPD2 are both dual-frequency DPDs, and the output thereof is a single-channel output.

In one embodiment, in order to implement two-way Outphasing of Outphasing signal separation circuit 100, a lookup table storing Outphasing information needs to be provided in Outphasing signal separation circuit 100, and in particular, Outphasing signal separation circuit 100 includes:

a first modulus unit 130, configured to connect to the first input terminal and perform modulus processing on the first baseband signal Band 1;

a second modulus unit 140, configured to connect to a second input terminal and perform modulus processing on the second baseband signal Band 2;

a first lookup table unit storing first Outphasing information, the first lookup table unit being configured to connect the first modulus unit 130 and the second modulus unit 140, and output a first Outphasing phase angle according to the first Outphasing information, a modulus value of the first baseband signal Band1, and a modulus value of the second baseband signal Band 2;

a second lookup table unit, storing second Outphasing information, for connecting the first modulus unit 130 and the second modulus unit 140, and outputting a second Outphasing phase angle according to the second Outphasing information, the modulus value of the first baseband signal Band1 and the modulus value of the second baseband signal Band 2;

a first multiplier 110, configured to connect a first input terminal and an output terminal of the first lookup table unit, multiply the first baseband signal Band1 with phase information represented by a first out phase angle, and output a first out phase separation signal; and

a second multiplier 120, for connecting the first input terminal and the output terminal of the second lookup table unit, multiplying the first baseband signal Band1 by the phase information represented by the second out-phasing phase angle, and outputting a second out-phasing separation signal.

The first modulus unit 130 and the second modulus unit 140 respectively perform modulus calculation on the first baseband signal Band1 and the second baseband signal Band2 to obtain a modulus value of the two baseband signals, where the modulus value is significant in quantifying the influence between the two concurrent baseband signals on the architecture efficiency of the power amplification circuit 500; because the Doherty operating mode of the Band2 will affect the Outphasing angle on the Band1, the modulus values of the two baseband signals are respectively input to the first lookup table unit and the second lookup table unit, the outputs of the first lookup table unit and the second lookup table unit are corresponding Outphasing phase angles at each power amplitude of the baseband signals, the angles represent the high efficiency state of the power amplifying circuit 500, and the operating mode of the power amplifier can be adjusted corresponding to the first baseband signal Band1 and the second baseband signal Band2 according to the Outphasing information contained in the lookup tables, so that the efficiency of the power amplifier is improved; it can be understood that, since the modulus values respectively input to the two lookup table units are two, the lookup tables stored in the first lookup table unit and the second lookup table unit are two-dimensional, i.e., 2D-LUT.

In an embodiment, the Outphasing signal separation circuit 100 further includes a first digital up-conversion unit DUC1 and a second digital up-conversion unit DUC2, wherein the first multiplier 110, the first digital up-conversion unit DUC1 and the first adder 300 are sequentially connected, and the second multiplier 120, the second digital up-conversion unit DUC2 and the second adder 400 are sequentially connected. The first Outphasing separation signal and the second Outphasing separation signal are modulated to medium-high frequency through a digital up-conversion technology, so that the design difficulty can be reduced, the data volume and the transmission speed of baseband data can be reduced, and the subsequent processing is facilitated.

In an embodiment, to adjust the Doherty separation signal, the Doherty signal separation circuit 200 further includes a signal adjusting unit, where the signal adjusting unit is configured to perform one or more of gain, phase and waveform adjustment on the second baseband signal, and the second baseband signal is processed by the signal adjusting unit to obtain the second path of Doherty separation signal. The signal adjusting unit is used for offsetting the disadvantages of a traditional Doherty circuit, generally speaking, an auxiliary power amplifier in the traditional Doherty circuit is biased in a C type, once the bias state is determined, the opening position of the auxiliary power amplifier is determined, so that the efficiency of the auxiliary power amplifier is reduced and cannot reach an ideal state, one or more of gain, phase and waveform can be adjusted through the signal adjusting unit, and the working efficiency of Doherty is improved, and the theoretical basis is that the strategies of flexibly configuring the opening position, power distribution ratio, phase adjustment and the like of an auxiliary power amplifier in a dual-input Doherty power amplifier are achieved through digital end control to improve the efficiency and linearity of the Doherty power amplifier and make up the characteristics of the traditional single-input Doherty power amplifier; for example, the gain of the signal is adjusted, more power is injected into the auxiliary power amplifier through unbalanced power distribution, on one hand, the opening position of the auxiliary power amplifier is controlled, on the other hand, the power distribution ratio of the auxiliary power amplifier is controlled, and therefore the Doherty power amplifier efficiency is maximized on the basis of keeping linear performance; for another example, the phase of the signal is adjusted, and the phase matching degree is higher by adjusting the phases of the two paths; the adjustment may also be performed in other ways, which are not exemplified herein.

Similarly, the design of the Doherty signal splitting circuit 200 can be made simpler by digital up-conversion technology, and the Doherty signal splitting circuit further includes a third digital up-conversion unit DUC3 and a fourth digital up-conversion unit DUC4, wherein the second baseband signal Band2 is processed by the third digital up-conversion unit DUC3 and then input to the first adder 300, and the second baseband signal Band2 is processed by the signal conditioning unit and the fourth digital up-conversion unit DUC4 and then input to the second adder 400.

It can be understood that, the power amplifier circuit 500 is not limited to which frequency Band supports the outbound operating mode and which frequency Band supports the Doherty operating mode, and different frequency bands may be selected as the Band1 signal and the Band2 signal in consideration of the operating performance and operating parameters of other components in the circuit design and the efficiency of the mixed rf output.

Based on the dual-input power amplification circuit 500, the outbound signal separation circuit 100 and the Doherty signal separation circuit 200 are arranged in a matched manner, so that the circuit structure is simplified, the first baseband signal Band1 and the second baseband signal Band2 are subjected to frequency mixing output through the signal separation circuits of two different working modes, the condition that the same impedance trend is met at different frequency points is not considered, the impedance trends corresponding to the two different power amplification working modes are selectable, and the design difficulty of a power amplification transmitter is reduced.

In the second embodiment, the first embodiment of the method,

as shown in fig. 3 and 4, the present embodiment provides a power amplifier transmitter, which includes

A first input terminal for inputting a first baseband signal, wherein the first baseband signal includes a plurality of first sub-baseband signals having different frequency bands;

a second input terminal for inputting a second baseband signal, wherein the second baseband signal includes a plurality of second sub-baseband signals having different frequency bands;

an Outphasing signal separation circuit 100, configured to connect to a first input end to perform signal separation processing on a first baseband signal, and output a first Outphasing separation signal and a second Outphasing separation signal, where the number of the Outphasing signal separation circuits 100 is the same as that of the first baseband signal;

the Doherty signal separating circuit 200 is configured to be connected to the second input terminal to perform signal separation processing on the second baseband signal, and output a first path of Doherty separated signal and a second path of Doherty separated signal based on Doherty time domain adjustment, where the number of the Doherty signal separating circuit 200 is the same as that of the second sub-baseband signal;

a first adder 300, configured to add the first outgoing separated signal and the first Doherty separated signal;

a second adder 400, configured to add the second outgoing separated signal and the second Doherty separated signal; and

the power amplification circuit 500 is configured to support an Outphasing operation mode in a frequency band of the first baseband signal and support a Doherty operation mode in a frequency band of the second baseband signal, and the power amplification circuit 500 is connected to output ends of the first adder 300 and the second adder 400, so as to perform power amplification on signals output by the first adder 300 and the second adder 400.

In this embodiment, a case of multi-frequency concurrent input is described, where each first sub-baseband signal is represented by Band1 to Band, and each second sub-baseband signal is represented by Band +1 to Band, where m and n are positive integers greater than 1, it is obvious that each first sub-baseband signal corresponds to one frequency Band, that is, the frequency bands included in the first baseband signal are greater than 1, and each second sub-baseband signal corresponds to one frequency Band, that is, the frequency bands included in the second baseband signal are more than 1.

Each frequency Band of the first sub-Band signal corresponds to one outputting signal separating circuit 100, each frequency Band of the second sub-Band signal corresponds to one Doherty signal separating circuit 200, specifically, out-of-phase information in each outputting signal separating circuit 100 corresponds to different first sub-Band signals, Doherty time domain adjustment in each Doherty signal separating circuit 200 corresponds to different second sub-Band signals, after the first sub-Band signals Band1 to Band and the second sub-Band signals Band +1 to Band are processed by the outputting signal separating circuit 100 and the Doherty signal separating circuit 200, the first adder 300 adds all the first outputting separating signals and the first Doherty separating signals to obtain different first outputting separating signals, second outputting separating signals, first Doherty separating signals and second Doherty separating signals, and finally, through one input end of the input power amplifying circuit 500, all the second outputting separating signals and the second Doherty separating signals are added through the second adder 400, to the other input terminal of the power amplifying circuit 500.

Based on the above situation of multi-frequency concurrent input, in order to implement digital processing and frequency band separation, improve the efficiency of the power amplifier circuit 500, and reduce the distortion generated when the power amplifier circuit 500 operates in its non-linear region, this embodiment further includes:

a first digital predistortion unit DPD1, connected to the first input terminal, for performing digital predistortion processing on the first sub-baseband signals Band1 to Band, and then inputting the first sub-baseband signals Band1 to Band into the Outphasing signal separation circuit 100;

a second digital predistortion unit DPD2, configured to be connected to the second input terminal to perform digital predistortion on the second sub-baseband signals Bandm +1 to Bandn, and then input the second sub-baseband signals Bandm +1 to Bandn to the Doherty signal separation circuit 200;

the first digital-to-analog conversion unit DAC1, the output terminal of the first adder 300 is connected to the power amplification circuit 500 through the first digital-to-analog conversion unit DAC 1; and

the output terminal of the second adder 400 is connected to the power amplifying circuit 500 through a second digital-to-analog converting unit DAC2, the second digital-to-analog converting unit DAC 2.

The first digital predistortion unit DPD1 and the second digital predistortion unit DPD2 are multi-input single-output DPD devices, and the description of the linear influence between the input frequency bands refers to the first embodiment, and will not be repeated here.

Since the structure of the single Outphasing signal separation circuit 100 and the single Doherty signal separation circuit 200 are the same as the Outphasing signal separation circuit 100 and the Doherty signal separation circuit 200 in the first embodiment, the input and output processing for the first sub-Band signals Band1 to Band and the second sub-Band signals Band +1 to Band are similar, and the structure and the operation of the single Outphasing signal separation circuit 100 and the single Doherty signal separation circuit 200 are not described in detail in order to avoid repeated description.

It should be noted that, since the signals are added, the first adder 300 and the second adder 400 are actually formed by cascading a plurality of sub-adders, each of which adds two signals and outputs one signal to a next sub-adder, thereby forming the first adder 300 and the second adder 400.

Based on the first embodiment and the second embodiment, an embodiment of the present invention further provides a power amplifier transmitter, which includes the power amplifier transmitter in the first embodiment or the second embodiment, wherein the power amplifier transmitter employs the power amplifier transmitter, the Outphasing signal separation circuit 100 is configured to perform Outphasing signal separation processing on the first baseband signal to obtain a first Outphasing separation signal and a second Outphasing separation signal, the Doherty signal separation circuit 200 is further configured to perform digital Doherty signal separation processing on the second baseband signal to obtain a first Doherty separation signal and a second Doherty separation signal, the first Outphasing separation signal and the first Doherty separation signal are added, the second Outphasing separation signal and the second Doherty separation signal are added to obtain two signals input to the power amplification circuit 500, the power amplification circuit 500 performs mixing processing and then combines and outputs an amplified radio frequency signal, compared with the existing double-input working mode framework, the embodiment of the invention does not need to meet the same impedance trend on different frequency points, but has the impedance trends corresponding to two different power amplifier working modes which can be selected, thereby simplifying the circuit structure and reducing the design difficulty of the power amplifier transmitter.

The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, and are not to be construed as limiting the scope of the invention. Any modifications, equivalents and improvements which may occur to those skilled in the art without departing from the scope and spirit of the present invention are intended to be within the scope of the claims.