WO2022062378A1

WO2022062378A1 - Pre-distortion system, radio frequency power amplifier system, tdd system and fdd system

Info

Publication number: WO2022062378A1
Application number: PCT/CN2021/088418
Authority: WO
Inventors: 李华鸿; 李军; 龚丽萍; 梁发兴
Original assignee: 浙江三维利普维网络有限公司; 三维通信股份有限公司
Priority date: 2020-09-28
Filing date: 2021-04-20
Publication date: 2022-03-31
Also published as: CN112290970A

Abstract

A pre-distortion system, a radio frequency power amplifier system, a TDD system and an FDD system. The pre-distortion system comprises a first switch (101), a digital pre-distortion unit (102), an analog pre-distortion unit (103), a second switch (104) and a feedback unit (106). The first switch (101) is used to selectively connect a radio frequency signal input terminal to one of the digital pre-distortion unit (102) and the analog pre-distortion unit (103). The second switch (104) is used to selectively connect one of the digital pre-distortion unit (102) and the analog pre-distortion unit (103) to a radio frequency power amplifier module (200). The feedback unit (106) is used to sample a feedback signal reflecting changes in a radio frequency signal outputted by the radio frequency power amplifier module (200), and feed the feedback signal into the analog pre-distortion unit (103) or the digital pre-distortion unit (102).

Description

Predistortion system, RF power amplifier system, TDD system and FDD system

Related applications

This application claims the priority of the Chinese patent application filed on September 28, 2020, the application number is 202011036875.9, and the invention name is "predistortion system, radio frequency power amplifier system, TDD system and FDD system", the entire contents of which are incorporated by reference in in this application.

technical field

The present application relates to the field of communication technologies, and in particular, to a predistortion system, a radio frequency power amplifier system, a TDD system and an FDD system.

Background technique

In modern communication systems, the linear modulation method is more and more widely used, therefore, it is necessary for the radio frequency system to have good linearity or linearity.

The linearization of the output of the radio frequency power amplifier system has become the focus of modern communication systems. In order to meet the linearization of the output of the radio frequency power amplifier system, the existing Anti-distortion in advance to compensate the nonlinear distortion generated by the power amplifier components, thereby improving the stability of the RF power amplifier system and widening the frequency width.

Pre-distortion systems include two categories: Digital Pre-Distortion (DPD) and Analog Pre-Distortion (APD). The pre-distortion systems of existing RF power amplifier systems generally use a single digital pre-distortion or The analog predistortion system has less flexibility; when faced with specific requirements for signal frequency and signal bandwidth, the existing predistortion system cannot meet the corresponding requirements.

Currently, no effective solution has been proposed for the problem that the single predistortion system in the related art has narrow adaptability to the signal frequency and signal bandwidth.

SUMMARY OF THE INVENTION

Embodiments of the present application provide a predistortion system, a radio frequency power amplifier system, a TDD system, and an FDD system, so as to at least solve the problem of narrow adaptability of a single predistortion system to signal frequency and signal bandwidth in the related art.

In a first aspect, an embodiment of the present application provides a predistortion system, the predistortion system includes a first switch, a digital predistortion unit, an analog predistortion unit, a second switch, and a feedback unit; wherein the first switch is used for selectively connecting the radio frequency signal input terminal to one of the digital predistortion unit and the analog predistortion unit; the second switch is used to selectively connect the digital predistortion unit to the analog predistortion unit One of the predistortion units is connected to the radio frequency power amplifier module; the input end of the feedback unit is connected to the output end of the radio frequency power amplifier module, and the output end of the feedback unit is respectively connected to the digital predistortion unit and the analog predistortion unit unit, the feedback unit is configured to sample a feedback signal reflecting the change of the radio frequency signal output by the radio frequency power amplifier module and selectively feed the feedback signal to one of the analog predistortion unit and the digital predistortion unit.

Optionally, the predistortion system further includes a main control unit, the main control unit is respectively connected to the first switch, the second switch, the analog predistortion unit and the digital predistortion unit, wherein ,

The main control unit is at least used to control the first switch to selectively connect the radio frequency signal input terminal to one of the digital predistortion unit and the analog predistortion unit, and to control the second switch to selectively Connect one of the digital predistortion unit and the analog predistortion unit to the radio frequency power amplifier module, and control the analog predistortion unit to perform predistortion processing and control on the radio frequency signal input to the analog predistortion unit The digital predistortion unit performs predistortion processing on the radio frequency signal input to the digital predistortion unit.

Optionally, the predistortion system further includes a DSP unit, the input end of the DSP unit is connected to the output end of the feedback unit, and the output end of the DSP unit is connected to the main control unit and the main control unit respectively. The digital predistortion unit; wherein the DSP unit is at least configured to perform digital signal processing on the feedback signal correspondingly output by the feedback unit.

Optionally, the feedback unit includes a first coupler and a third switch, wherein the first coupler includes a first input end, a first output end and a second output end, and the third switch includes a seventh port, eighth port and ninth port, the first input end is connected to the output end of the radio frequency power amplifier module, the first output end is connected to the radio frequency signal output end, and the second output end is connected to the first Seven ports, the eighth port is connected to the analog predistortion unit, and the ninth port is connected to the DSP unit; wherein, the first coupler is used for sampling feedback reflecting the change of the radio frequency signal output by the radio frequency power amplifier module signal, the third switch is used to selectively connect the seventh port with one of the eighth port and the ninth port, so that the feedback signal is fed into the analog predistortion unit and one of the DSP units.

Optionally, the analog predistortion unit includes a first signal acquisition unit, a first predistortion unit, a delay circuit unit, and a correction signal output unit, and the first signal acquisition unit is provided with a second input terminal and a third output. terminal and a fourth output terminal, the correction signal output unit is provided with a third input terminal, a fourth input terminal and a fifth output terminal, the second input terminal is connected to the third port of the first switch, the first The three output terminals are connected to the input terminal of the delay circuit unit, the fourth output terminal is connected to the input terminal of the first predistortion unit, and the output terminal of the first predistortion unit is connected to the third input terminal, The output end of the delay circuit unit is connected to the fourth input end, and the fifth output end is connected to the fifth port of the second switch; wherein, the first signal acquisition unit is used for the input radio frequency signal Sampling is performed, and the sampled first sampling signal is sent to the first predistortion unit; the first predistortion unit is used for generating a correction signal according to the first sampling signal; the delay circuit unit is used for The input radio frequency signal is time-delayed; the correction signal output unit is configured to couple and superimpose the radio frequency signal delayed by the time delay circuit unit and the correction signal.

Optionally, the first signal acquisition unit includes a second coupler, and/or the correction signal output unit includes a third coupler.

Optionally, the first switch and the second switch are both SPDT radio frequency microwave electronic switches; and/or the third switch is a SPDT radio frequency microwave electronic switch.

In a second aspect, an embodiment of the present application provides a radio frequency power amplifier system, the radio frequency power amplifier system includes a predistortion system and a radio frequency power amplifier module, an input end of the predistortion system is connected to a radio frequency signal input end, and an input end of the predistortion system is connected to a radio frequency signal input end. The output end is connected to the input end of the radio frequency power amplifier module, and the output end of the radio frequency power amplifier module is connected to the output end of the radio frequency power amplifier system, wherein the predistortion system includes the predistortion system of the first aspect.

Optionally, the radio frequency power amplifier module includes a plurality of cascaded radio frequency amplifying units, and each of the radio frequency amplifying units includes at least one radio frequency amplifier, wherein the radio frequency amplifier is used for outputting an output terminal along the predistortion system. The output RF signal is amplified.

In a third aspect, an embodiment of the present application provides a TDD system, including a first radio frequency power amplifier system, a first isolator, a first antenna, a fourth switch, and a first power amplifier uplink; the first isolator includes a first isolator Five input ends, a sixth output end and a seventh output end, the fourth switch includes a tenth port, an eleventh port and a twelfth port, the input end of the first radio frequency power amplifier system is connected to the radio frequency signal input end, The output end of the first radio frequency power amplifier system is connected to the fifth input end, the sixth output end is connected to the first antenna, the seventh output end is connected to the tenth port, and the eleventh port The input end of the uplink of the first power amplifier is connected, and the twelfth port is pulled down to the ground, wherein the first radio frequency power amplifier system includes the radio frequency power amplifier system of the second aspect.

Optionally, the fourth switch includes a single-pole double-throw radio frequency microwave electronic switch, and/or the first power amplifier uplink includes a radio frequency amplifier.

In a fourth aspect, an embodiment of the present application provides an FDD system, including a second power amplifier downlink and a second power amplifier uplink arranged in parallel; wherein the second power amplifier downlink includes a second radio frequency connected in sequence A power amplifier system and a second isolator, the output end of the second radio frequency power amplifier system is connected to the input end of the second isolator, and the second radio frequency power amplifier system includes the radio frequency power amplifier system described in the second aspect; the The second power amplifier uplink includes a radio frequency amplifier.

Compared with the related art, the present application provides a predistortion system, a radio frequency power amplifier system, a TDD system and an FDD system. The predistortion system includes a first switch, a digital predistortion unit, an analog predistortion unit, a second switch and a feedback unit; the first switch is used to selectively connect the radio frequency signal input end with one of the digital predistortion unit and the analog predistortion unit; the second switch is used to selectively connect one of the digital predistortion unit and the analog predistortion unit One is connected to the radio frequency power amplifier module; the input end of the feedback unit is connected to the output end of the radio frequency power amplifier module, the output end of the feedback unit is respectively connected to the digital predistortion unit and the analog predistortion unit, and the feedback unit is used to sample and reflect the radio frequency signal output by the radio frequency power amplifier module The changing feedback signal is selectively fed into the analog predistortion unit or the digital predistortion unit. By controlling the first switch and the second switch to switch on, the digital predistortion unit or the analog predistortion unit is connected with the RF power amplifier module, which is suitable for predistortion of different frequencies and signal bandwidths, and realizes the analog predistortion system and the digital predistortion system. Switching within the same power amplifier module solves the problem of narrow adaptability of a single predistortion system to signal frequency and signal bandwidth, making the RF power amplifier system adapt to multi-band and multi-standard modulation methods, and maintain the linearity of the output signal.

The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below in order to make other features, objects and advantages of the application more apparent.

Description of drawings

1 is a schematic structural diagram of a connection between a predistortion system and a radio frequency power amplifier module according to an embodiment of the present application;

2 is a schematic structural diagram 1 of the connection between a predistortion system and a radio frequency power amplifier module according to a preferred embodiment of the present application;

FIG. 3 is a second structural schematic diagram of the connection between a predistortion system and a radio frequency power amplifier module according to a preferred embodiment of the present application;

4 is a schematic diagram of a topology structure of the connection between a predistortion system and a radio frequency power amplifier module according to a preferred embodiment of the present application;

5 is a schematic structural diagram of a radio frequency power amplifier system according to an embodiment of the present application;

6 is a schematic structural diagram of a TDD system according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of an FDD system according to an embodiment of the present application.

detailed description

In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application. In addition, it will also be appreciated that while such development efforts may be complex and lengthy, for those of ordinary skill in the art to which the present disclosure pertains, the techniques disclosed in this application Some changes in design, manufacture or production based on the content are only conventional technical means, and it should not be understood that the content disclosed in this application is not sufficient.

Reference in this application to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor a separate or alternative embodiment that is mutually exclusive of other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

Unless otherwise defined, the technical or scientific terms involved in this application shall have the usual meanings understood by those with ordinary skill in the technical field to which this application belongs. Words such as "a", "an", "an", "the" and the like mentioned in this application do not denote a quantitative limitation, and may denote the singular or the plural. The terms "comprising", "comprising", "having" and any of their variants referred to in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or process comprising a series of steps or modules (units) The apparatus is not limited to the steps or units listed, but may further include steps or units not listed, or may further include other steps or units inherent to the process, method, product or apparatus. Words like "connected," "connected," "coupled," and the like referred to in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "plurality" referred to in this application means greater than or equal to two. "And/or" describes the association relationship between associated objects, indicating that there can be three kinds of relationships. For example, "A and/or B" can mean that A exists alone, A and B exist at the same time, and B exists alone. The terms "first", "second", "third", etc. involved in this application are only to distinguish similar objects, and do not represent a specific order for the objects.

The various technologies described in this application can be used in various wireless communication systems, such as 2G, 3G, 4G, 5G communication systems and next-generation communication systems, such as the Global System for Mobile communications (GSM for short), Code Division Multiple Access (CDMA) system, Time Division Multiple Access (TDMA) system, Wideband Code Division Multiple Access Wireless (WCDMA), frequency Frequency Division Multiple Access (Frequency Division Multiple Addressing, referred to as FDMA) system, Orthogonal Frequency Division Multiple Access (Orthogonal Frequency-Division Multiple Access, referred to as OFDMA) system, Single-Carrier FDMA (SC-FDMA) system, General Packet Radio Service ( General Packet Radio Service, referred to as GPRS) system, Long Term Evolution (Long Term Evolution, referred to as LTE) system, 5G New Radio (New Radio, referred to as NR) system and other such communication systems.

The predistortion system and the radio frequency power amplifier system provided in this application can be integrated into a base station, a radio remote unit (Radio Remote Unit, RRU for short), or any other network element equipment that needs to perform radio frequency transmission and reception. A base station in this application may be a device in an access network that communicates with wireless terminals over the air interface through one or more sectors. The base station can be used to convert received air frames and Internet Protocol (IP) packets to each other, and act as a router between the wireless terminal and the rest of the access network, where the rest of the access network can include IP The internet. The base station may also coordinate attribute management of the air interface. For example, the base station may be a base station (Base Transceiver Station, abbreviated as BTS) in GSM or CDMA, a base station (Node B) in WCDMA, or an evolved base station (evolutional Node B, abbreviated as eNB) in LTE or e-Node B), and may also be a generation Node B in 5G NR (referred to as gNB for short), which is not limited in this application. Before describing and illustrating the embodiments of the present application, the related technologies used in the present application are described as follows:

Pre-distortion is to pre-distort the input signal by inserting a pre-distortion module (PD) with the opposite characteristics of the characteristic response of the power amplifier element between the input signal and the power amplifier element (PA), and then send it to the power amplifier element. In order to compensate for AM-AM (amplitude distortion) and AM-PM (phase distortion) generated by nonlinear power amplifier components, the input and output of the entire pre-distortion module (PD) and power amplifier (PA) cascade circuit present a linear relationship.

Digital pre-distortion (Digital Pre-Distortion, DPD) is mainly used to pre-distort the signal whose single carrier is a wideband signal (5MHz-100MHz). The digital pre-distortion is pre-distorted by the integrated DPD algorithm.

Analog pre-distortion (Analog Pre-Distortion, APD) is mainly used to pre-distort the signal whose single carrier is a narrowband signal (200KHz~5MHz). Meanwhile, analog predistortion is mainly used in radio frequency predistortion.

A digital signal processing chip (Digital Signal Processor, DSP) is a unique microprocessor, a device that processes a large amount of information with digital signals. In mobile communication products, it is usually used to cooperate with DPD to realize the algorithm function of signal nonlinear compensation.

The embodiment of the present application provides a predistortion system. FIG. 1 is a schematic structural diagram of the connection between a predistortion system and a radio frequency power amplifier module according to an embodiment of the present application. As shown in FIG. 1 , the predistortion system 100 includes a first switch 101, a digital predistortion unit 102, an analog predistortion unit 103, a Two switches 104 and a feedback unit 106; wherein, the first switch 101 is used to selectively connect the radio frequency signal input terminal RF-IN to one of the digital predistortion unit 102 and the analog predistortion unit 103; the second switch 104 is used for Selectively connect one of the digital predistortion unit 102 and the analog predistortion unit 102 to the radio frequency power amplifier module 200; the input end of the feedback unit 106 is connected to the output end of the radio frequency power amplifier module 200, and the output end of the feedback unit 106 is respectively connected to the digital predistortion unit. The distortion unit 102 and the analog predistortion unit 103, and the feedback unit 106 is used to sample the feedback signal reflecting the change of the radio frequency signal output by the radio frequency power amplifier module 200 and selectively feed it into one of the analog predistortion unit 103 and the digital predistortion unit 102 .

Optionally, the first switch 101 includes a first port, a second port and a third port; the second switch 104 includes a fourth port, a fifth port and a sixth port; the first port is connected to the radio frequency signal input terminal RF-IN , the second port is connected to the input of the digital predistortion unit 102, the output of the digital predistortion unit 102 is connected to the fourth port, the third port is connected to the input of the analog predistortion unit 103, and the output of the analog predistortion unit 103 The first switch 101 connects the first port with the second port, so that the RF signal input terminal RF-IN is connected with the digital predistortion unit 102, and the second switch 104 The fourth port is connected with the sixth port, and the digital predistortion unit 102 is connected with the radio frequency power amplifier module 200; The second switch 104 is connected to connect the fifth port with the sixth port, so that the analog predistortion unit 103 is connected to the radio frequency power amplifier module 200 .

Optionally, the first switch 101 and the second switch 104 are both single-pole double-throw radio frequency microwave electronic switches.

In the embodiment of the present application, when the first switch 101 connects the first port with the second port, and the second switch 104 connects the fourth port with the sixth port, the radio frequency signal input terminal RF-IN is connected to the digital signal through the first switch 101 The predistortion unit 102, the digital predistortion unit 102 is connected to the radio frequency power amplifier module 200 through the second switch 104, the output of the radio frequency power amplifier module 200 is connected to the feedback unit 106, the radio frequency signal input terminal RF-IN, the first switch 101, the digital predistortion unit 102 and The second switch 104 corrects the digital pre-distortion algorithm based on the signal fed back by the feedback unit 106 to form a corresponding digital pre-distortion link; the first switch 101 connects the first port with the third port, and the second switch 104 connects the fifth port with the When the sixth port is connected, the RF signal input terminal RF-IN is connected to the analog predistortion unit 103 through the first switch 101 , the analog predistortion unit 103 is connected to the RF power amplifier module 200 through the second switch 104 , and the output of the RF power amplifier module 200 is connected to the feedback unit 106 , the RF signal input terminal RF-IN, the first switch 101 , the analog predistortion unit 103 and the second switch 104 , and the analog predistortion algorithm is corrected based on the signal fed back by the feedback unit 106 to form an analog predistortion link.

It should be noted that the digital predistortion unit 102 in this embodiment of the present application stores a corresponding DPD algorithm, and the DPD algorithm cooperates with the radio frequency power amplifier module 200 to adaptively maintain the output linearity of the radio frequency power amplifier module 200 . The analog predistortion unit 103 cooperates with the radio frequency power amplifier module 200 through an internal analog predistortion link to adaptively maintain the output linearity of the radio frequency power amplifier module 200 .

In the embodiment of the present application, the digital predistortion unit 102 is implemented by an integrated digital processing chip, wherein the integrated digital processing chip is configured with a DSP function block, which can realize DPD correction, but because the integrated digital processing chip does not support DPD correction in the dedicated network frequency band Therefore, in the embodiment of the application, for a private network product in a special private network frequency band, it is necessary to realize signal correction through the APD function, so as to obtain the output linearity that meets the product requirements. The embodiment of the present application also implements narrowband signal correction through the APD function, which is used to solve the problem that the correction effect of the narrowband signal with the processing frequency of the DPD algorithm in the range of 200KHz-5MHz is not ideal. The predistortion system of the embodiment of the present application controls the first switch 101 It is switched on with the second switch 104 to realize the communication between the digital predistortion unit 102 or the analog predistortion unit 103 and the radio frequency power amplifier module 200, so as to apply the predistortion of different frequencies and signal bandwidths, and realize the analog predistortion system and the digital predistortion system. Switching within the same power amplifier module solves the problem of the narrow adaptability of a single predistortion system to signal frequency and signal bandwidth in the related art, making the RF power amplifier system adapt to multi-band and multi-standard modulation methods, keeping the output signal with good linearity Spend.

FIG. 2 is a schematic structural diagram 1 of the connection between the pre-distortion system and the radio frequency power amplifier module according to the preferred embodiment of the present application. As shown in FIG. 2 , the pre-distortion system 100 further includes a main control unit 105. The main control unit 105 is connected to the first switch 101 respectively. , the second switch 104, the analog predistortion unit 103 and the digital predistortion unit 102 are connected, wherein the main control unit 105 is at least used to control the first switch 101 to selectively connect the radio frequency signal input terminal (corresponding to the first port) with the digital predistortion unit 102. One of the distortion unit 102 (corresponding to the second port) and the analog predistortion unit 103 (corresponding to the third port) is connected, and the second switch 104 is controlled to connect the digital predistortion unit 102 (corresponding to the fourth port) and the analog predistortion unit 103 ( Corresponding to the fifth port), one of which is selectively connected to the radio frequency power amplifier module 200 (corresponding to the sixth port), and controls the analog predistortion unit 103 to perform predistortion processing on the radio frequency signal input to the analog predistortion unit 103 along the third port, and The digital predistortion unit 102 is controlled to perform predistortion processing on the radio frequency signal input to the digital predistortion unit 102 along the second port.

In the embodiment of the present application, the main control unit 105 outputs a switching instruction, controls the first switch 101 to connect the first port with the second port, and controls the second switch 104 to connect the fourth port with the sixth port, so that the radio frequency signal input end The RF-IN is connected to the digital predistortion unit 102 through the first switch 101, and the digital predistortion unit 102 is connected to the radio frequency power amplifier module 200 through the second switch 104, thereby forming a digital predistortion chain; at the same time, the digital predistortion unit 102 is connected by The stored DPD algorithm cooperates with the radio frequency power amplifier module 200 to adaptively maintain the output linearity of the radio frequency power amplifier module 200 .

In the embodiment of the present application, the main control unit 105 outputs a switching instruction, controls the first switch 101 to connect the first port with the third port, and controls the second switch 104 to connect the fifth port with the sixth port, so that the radio frequency signal input end The RF-IN is connected to the analog predistortion unit 103 through the first switch 101, and the analog predistortion unit 103 is connected to the RF power amplifier module 200 through the second switch 104, thereby forming an analog predistortion chain; at the same time, the analog predistortion unit 103 is connected through The internal analog predistortion link cooperates with the radio frequency power amplifier module 200 to adaptively maintain the output linearity of the radio frequency power amplifier module 200 .

It should be noted that, in this embodiment of the present application, the main control unit 105 includes but is not limited to one of the following: a single-chip microcomputer, a PFGA, and a DSP.

In this embodiment of the present application, the main control unit 105 is connected to the analog predistortion unit 103 through SPI serial communication, and is also connected to the digital predistortion unit 102 through SPI serial communication.

FIG. 3 is a second structural schematic diagram of the connection between the predistortion system and the radio frequency power amplifier module according to the preferred embodiment of the present application. As shown in FIG. 3 , the predistortion system 100 further includes a DSP unit 109 , and the input end of the feedback unit 106 is connected to the radio frequency power amplifier module 200 . The output end of the feedback unit 106 is connected to the analog predistortion unit 103 and the DSP unit 109 respectively. The DSP unit 109 is also connected to the main control unit 105 and the digital predistortion unit 102, wherein the feedback unit 106 is used for sampling and responding to the RF power amplifier. The changed feedback signal of the radio frequency signal output by the module 200 is selectively fed into one of the analog predistortion unit 103 and the DSP unit 109 ;

In the embodiment of the present application, the DSP unit 109, the module predistortion unit 103 and the main control unit 105 are all connected through SPI serial communication, and the main control unit 105 can control the DSP unit 109 to perform digital signal processing on the feedback signal and control the DSP unit 109 to communicate with Data interaction of the digital predistortion unit 102 .

In this embodiment of the present application, the feedback signal fed into the analog predistortion unit 103 is used as the feedback data support of the analog predistortion algorithm corresponding to the analog predistortion link inside the analog predistortion unit 103 .

In the embodiment of the present application, the feedback signal fed into the digital predistortion unit 102 is first fed into the DSP unit 109, the DSP unit 109 performs digital signal processing on the feedback signal, and the DSP unit 109 completes the digital signal processing and transmits it to the digital predistortion unit 102, and the processed feedback signal is used as the feedback data support of the digital pre-distortion algorithm stored in the digital pre-distortion unit 102, and at the same time, the digital pre-distortion algorithm can also be stored in the DSP unit 109. After integration, the digital pre-distortion unit 102 performs digital pre-distortion processing on the radio frequency signal to form data.

FIG. 4 is a schematic diagram of the topology of the connection between the predistortion system and the radio frequency power amplifier module according to the preferred embodiment of the present application. As shown in FIG. 4 , the feedback unit 106 includes a first coupler 107 and a third switch 108 , wherein the first coupler 107 includes a first input end, a first output end and a second output end, the third switch 108 includes a seventh port, an eighth port and a ninth port, the first input end is connected to the output end of the radio frequency power amplifier module 200, the first output end The terminal is connected to the RF signal output terminal RF-OUT, the second output terminal is connected to the seventh port, the eighth port is connected to the analog predistortion unit 103, and the ninth port is connected to the DSP unit 109; wherein, the first coupler 107 is used for sampling and responding to the RF power amplifier. The feedback signal of the RF signal change output by the module 200, the third switch 108 is used to selectively connect the seventh port with one of the eighth port and the ninth port, so that the feedback signal is fed into the analog predistortion unit 103 and the DSP correspondingly One of the units 109.

Optionally, the third switch 108 is a single-pole double-throw radio frequency microwave electronic switch.

Optionally, the analog predistortion unit 103 includes a first signal acquisition unit 11, a first predistortion unit 12, a delay circuit unit 13 and a correction signal output unit 14, and the first signal acquisition unit 11 is provided with a second input terminal, a first Three output terminals and a fourth output terminal, the correction signal output unit 14 is provided with a third input terminal, a fourth input terminal and a fifth output terminal, the second input terminal is connected to the third port, and the third output terminal is connected to the delay circuit unit 13 , the fourth output end is connected to the input end of the first predistortion unit 12, the output end of the first predistortion unit 12 is connected to the third input end, the output end of the delay circuit unit 13 is connected to the fourth input end, the fifth The output end is connected to the fifth port; wherein, the first signal acquisition unit 11 is used for sampling the input radio frequency signal, and transmits the sampled first sampled signal to the first predistortion unit 12; the first predistortion unit 12 is used for The correction signal is generated according to the first sampling signal; the time delay circuit unit 13 is used for delaying the input radio frequency signal; the correction signal output unit 14 is used for coupling and superposing the radio frequency signal delayed by the time delay circuit unit 13 and the correction signal .

Optionally, the first signal acquisition unit 11 includes a second coupler, and/or the correction signal output unit 14 includes a third coupler.

The following describes the working process of the predistortion system 100 according to the embodiment of the present application based on FIG. 4 :

When the predistortion system 100 uses a digital predistortion link to perform signal predistortion processing, the radio frequency power amplifier signal is connected to the radio frequency signal input terminal RF_IN, the first switch 101 connects the first port with the second port, and the radio frequency power amplifier signal passes through the first port and the second port. A switch 101 flows to the digital predistortion unit 102, after that, the second switch 104 connects the fourth port with the sixth port, and the digitally predistorted radio frequency signal flows to the radio frequency power amplifier module 200 through the second switch 104, and passes through the radio frequency power amplifier module. 200 is amplified and output along the RF signal output terminal RF_OUT; after the amplified RF signal passes through the first coupler 107, the output RF signal is sampled to obtain a feedback signal, and the feedback signal flows to the third switch 108, and the third switch 108 will The seventh port is connected to the ninth port, and after the feedback signal is transmitted to the DSP unit 109 , the DSP unit 109 uses the feedback signal as the feedback data support of the digital predistortion algorithm stored in the digital predistortion unit 102 . It should be noted that the digital predistortion algorithm may be stored in the digital predistortion unit 102 itself, or may be stored in the DSP unit 109. In this embodiment of the present application, the digital predistortion algorithm is stored in the DSP unit 106.

When the predistortion system 100 uses the analog predistortion link to perform signal predistortion processing, the radio frequency power amplifier signal is connected to the radio frequency signal input terminal RF_IN, the first switch 101 connects the first port with the third port, and the radio frequency power amplifier signal passes through the first port and the third port. A switch 101 flows to the analog predistortion unit 103, and the RF power amplifier signal flowing to the analog predistortion unit 103 is first coupled to the first predistortion unit 12 and the delay circuit unit 13 through the first signal acquisition unit 11, and the delay circuit unit 13 pairs The RF power amplifier signal undergoes a delay of 0 to 4 ns. The first predistortion unit 12 quantifies the RF power amplifier signal and generates a correction signal. The delayed RF power amplifier signal and the correction signal flow to the correction signal output unit 14 and are sent to the correction signal output unit by the correction signal output unit. 14 is superimposed and then flows to the second switch 104. After that, the second switch 104 connects the fifth port with the sixth port, and the analog predistorted radio frequency signal flows to the radio frequency power amplifier module 200 through the second switch 104 and passes through the radio frequency power amplifier module 200. After the amplification, it is output along the RF signal output terminal RF_OUT; after the amplified RF signal passes through the first coupler 107, the sampling of the output RF signal is completed, and a feedback signal is obtained, and the feedback signal flows to the third switch 108, and the third switch 108 converts the first The seventh port is connected to the eighth port, and after the feedback signal is transmitted to the first predistortion unit 12, the first predistortion unit 12 uses the feedback signal as the feedback data support for the analog predistortion performed by the first predistortion unit 12, wherein the radio frequency power amplifier signal When passing through the first signal acquisition unit 11 , the input RF power amplifier signal will be sampled, and the sampled signal will be input to the first predistortion unit 12 and used as the data support for the analog predistortion processing performed by the first predistortion unit 12 . The unit 12 performs quantization calculation on the sampled signal and outputs a corrected signal.

The embodiment of the present application provides a radio frequency power amplifier system. FIG. 5 is a schematic structural diagram of a radio frequency power amplifier system according to an embodiment of the present application. As shown in FIG. 5 , the radio frequency power amplifier system 300 includes a predistortion system 100 and a radio frequency power amplifier module 200 , and the input end of the predistortion system 100 is connected to the radio frequency signal input end RF -IN, the output end of the predistortion system 100 is connected to the input end of the radio frequency power amplifier module 200, and the output end of the radio frequency power amplifier module 200 is connected to the output end of the radio frequency power amplifier system 300 (refer to RF-OUT in FIG. 5), wherein the predistortion system The predistortion system 100 described above is included.

Optionally, the radio frequency power amplifier module 200 includes a plurality of cascaded radio frequency amplifier units 21, and each radio frequency amplifier unit 21 includes at least one radio frequency amplifier, wherein the radio frequency amplifier is used for the output of the radio frequency signal along the output end of the predistortion system 100. to zoom in.

It should be noted that, in the embodiments of the present application, the radio frequency amplifier includes but is not limited to a Doherty amplifier. At the same time, in the embodiment of the present application, the predistortion system 100 performs predistortion processing on the input RF power amplifier signals of different signal frequencies and signal bandwidths, and then performs amplification through the cascaded RF power amplifier modules 200. "Anti-distortion" compensates the nonlinear distortion of the radio frequency power amplifier module 200, so that the input and output of the radio frequency power amplifier system 300 exhibit a linear relationship, and the radio frequency power amplifier system 300 is adapted to multi-band and multi-standard modulation.

An embodiment of the present application provides a TDD system. FIG. 6 is a schematic structural diagram of a TDD system according to an embodiment of the present application. As shown in FIG. 6 , the TDD system includes a first radio frequency power amplifier system, a first isolator 401 , and a first antenna. 402, the fourth switch 403 and the first power amplifier uplink 404; the first isolator 401 includes a fifth input end, a sixth output end and a seventh output end, and the fourth switch 403 includes a tenth port, an eleventh port and The twelfth port, the input end of the first radio frequency power amplifier system is connected to the radio frequency signal input end RF-IN, the output end of the first radio frequency power amplifier system is connected to the fifth input end, the sixth output end is connected to the first antenna 402, and the seventh output end The tenth port is connected, the eleventh port is connected to the input end of the uplink 404 of the first power amplifier, and the twelfth port is pulled down to the ground, wherein the first radio frequency power amplifier system includes the above-mentioned radio frequency power amplifier system 300 .

Optionally, the fourth switch 403 includes a single-pole double-throw radio frequency microwave electronic switch, and/or the first power amplifier uplink 404 includes a radio frequency amplifier.

Optionally, the first isolator 401 can be a ring coupler.

An embodiment of the present application provides an FDD system. FIG. 7 is a schematic structural diagram of an FDD system according to an embodiment of the present application. As shown in FIG. 7 , the FDD system includes a second power amplifier downlink and a second power amplifier uplink set in parallel Circuit 501; wherein, the second power amplifier downlink includes a second radio frequency power amplifier system and a second isolator 502 connected in sequence, the output end of the second radio frequency power amplifier system is connected to the input end of the second isolator 502, and the second radio frequency power amplifier The system includes the above-mentioned radio frequency power amplifier system 300; the second power amplifier uplink 501 includes a radio frequency amplifier.

Those skilled in the art should understand that the technical features of the above embodiments can be combined arbitrarily. In order to simplify the description, all possible combinations of the technical features in the above embodiments are not described. However, as long as these technical features There is no contradiction in the combination of the above, and they should be considered to be within the scope of the description in this specification.

The above examples only represent several embodiments of the present application, and the descriptions thereof are relatively specific and detailed, but should not be construed as a limitation on the scope of the invention patent. It should be pointed out that for those skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the scope of protection of the patent of the present application shall be subject to the appended claims.

Claims

A predistortion system, characterized in that the predistortion system comprises a first switch, a digital predistortion unit, an analog predistortion unit, a second switch and a feedback unit; wherein,

the first switch is used for selectively connecting the radio frequency signal input terminal to one of the digital predistortion unit and the analog predistortion unit;

the second switch is used to selectively connect one of the digital predistortion unit and the analog predistortion unit to the radio frequency power amplifier module;

The input end of the feedback unit is connected to the output end of the radio frequency power amplifier module, the output end of the feedback unit is respectively connected to the digital predistortion unit and the analog predistortion unit, and the feedback unit is used for sampling and reflecting the The changed feedback signal of the radio frequency signal output by the radio frequency power amplifier module is selectively fed into one of the analog predistortion unit and the digital predistortion unit.
The predistortion system according to claim 1, wherein the predistortion system further comprises a main control unit, the main control unit is respectively connected with the first switch, the second switch, the analog predistortion unit and the The digital predistortion unit is connected where,

The main control unit is at least used to control the first switch to selectively connect the radio frequency signal input end to the digital predistortion unit or the analog predistortion unit, and to control the second switch to selectively connect the radio frequency signal input terminal to the digital predistortion unit or the analog predistortion unit. The digital predistortion unit or the analog predistortion unit is connected to the radio frequency power amplifier module, the analog predistortion unit is controlled to perform predistortion processing on the radio frequency signal input to the analog predistortion unit, and the digital predistortion unit is controlled to the input The radio frequency signal sent to the digital predistortion unit is subjected to predistortion processing.
The predistortion system according to claim 2, wherein the predistortion system further comprises a DSP unit, the input terminal of the DSP unit is connected to the output terminal of the feedback unit, and the output terminals of the DSP unit are respectively connected to The main control unit and the digital predistortion unit; wherein the DSP unit is at least configured to perform digital signal processing on the feedback signal correspondingly output by the feedback unit.
The predistortion system of claim 3, wherein the feedback unit includes a first coupler and a third switch, wherein the first coupler includes a first input terminal, a first output terminal, and a second output terminal , the third switch includes a seventh port, an eighth port and a ninth port, the first input end is connected to the output end of the radio frequency power amplifier module, the first output end is connected to the radio frequency signal output end, so The second output end is connected to the seventh port, the eighth port is connected to the analog predistortion unit, and the ninth port is connected to the DSP unit; wherein, the first coupler is used for sampling and reflecting the radio frequency The feedback signal of the radio frequency signal change output by the power amplifier module, the third switch is used to selectively connect the seventh port with one of the eighth port and the ninth port, so that the feedback signal corresponds to Feed into one of the analog predistortion unit and the DSP unit.
The predistortion system according to claim 1, wherein the analog predistortion unit comprises a first signal acquisition unit, a first predistortion unit, a delay circuit unit and a correction signal output unit, and the first signal acquisition unit is configured to There are a second input end, a third output end and a fourth output end, the correction signal output unit is provided with a third input end, a fourth input end and a fifth output end, the second input end is connected to the first The third port of the switch, the third output end is connected to the input end of the delay circuit unit, the fourth output end is connected to the input end of the first predistortion unit, and the output of the first predistortion unit terminal is connected to the third input terminal, the output terminal of the delay circuit unit is connected to the fourth input terminal, and the fifth output terminal is connected to the fifth port of the second switch; wherein, the first signal The acquisition unit is configured to sample the input radio frequency signal, and transmit the sampled first sampled signal to the first predistortion unit; the first predistortion unit is configured to generate a correction signal according to the first sampled signal; The time delay circuit unit is used for delaying the input radio frequency signal; the correction signal output unit is used for coupling and superposing the radio frequency signal delayed by the time delay circuit unit and the correction signal.
The predistortion system according to claim 5, wherein the first signal acquisition unit includes a second coupler, and/or the correction signal output unit includes a third coupler.
The predistortion system according to any one of claims 1 to 6, wherein the first switch and the second switch are both SPDT RF microwave electronic switches; and/or the third switch is SPDT RF microwave electronic switch.
A radio frequency power amplifier system, characterized in that the radio frequency power amplifier system includes a predistortion system and a radio frequency power amplifier module, the input end of the predistortion system is connected to a radio frequency signal input end, and the output end of the predistortion system is connected to the radio frequency The input end of the power amplifier module, and the output end of the radio frequency power amplifier module is connected to the output end of the radio frequency power amplifier system, wherein the predistortion system includes the predistortion system according to any one of claims 1 to 7 .
The radio frequency power amplifier system according to claim 8, wherein the radio frequency power amplifier module includes a plurality of cascaded radio frequency amplifier units, each of the radio frequency amplifier units includes at least one radio frequency amplifier, wherein the radio frequency amplifier is used to The radio frequency signal output along the output end of the predistortion system is amplified.
A TDD system, characterized in that it includes a first radio frequency power amplifier system, a first isolator, a first antenna, a fourth switch, and a first power amplifier uplink; the first isolator includes a fifth input end, a sixth an output end and a seventh output end, the fourth switch includes a tenth port, an eleventh port and a twelfth port, the input end of the first radio frequency power amplifier system is connected to the radio frequency signal input end, the first radio frequency power amplifier The output end of the system is connected to the fifth input end, the sixth output end is connected to the first antenna, the seventh output end is connected to the tenth port, and the eleventh port is connected to the first power amplifier The input end of the uplink, the twelfth port is pulled down to the ground, wherein the first radio frequency power amplifier system comprises the radio frequency power amplifier system of claim 8 or 9.
The TDD system of claim 10, wherein the fourth switch comprises a single pole double throw radio frequency microwave electronic switch, and/or the first power amplifier uplink comprises a radio frequency amplifier.
An FDD system, characterized in that it includes a second power amplifier downlink and a second power amplifier uplink arranged in parallel; wherein the second power amplifier downlink includes a second radio frequency power amplifier system and a second isolation system connected in sequence The output end of the second radio frequency power amplifier system is connected to the input end of the second isolator, and the second radio frequency power amplifier system comprises the radio frequency power amplifier system of claim 8 or 9; the second power amplifier is upstream The link includes radio frequency amplifiers.