WO2022083098A1 - Radio frequency power amplification module - Google Patents

Abstract

A radio frequency power amplification module. The functional units of the radio frequency power amplification module are respectively arranged on a first circuit board and a second circuit board; the first circuit board comprises a first physical connection structure and a first electrical interface, and the second circuit board comprises a second physical connection structure and a second electrical interface; the functional units of the radio frequency power amplification module comprise a final-stage power amplifier; the final-stage power amplifier is provided on the first circuit board; the first physical connection structure and the second physical connection structure are used for fixing the first circuit board and the second circuit board; and the first electrical interface and the second electrical interface are used for providing an electrical connection between the first circuit board and the second circuit board.

Description

RF power amplifier module

Related applications

This application claims the priority of the Chinese patent application filed on October 22, 2020, the application number is 202011137299.7, and the invention name is "a radio frequency power amplifier module", the entire contents of which are incorporated into this application by reference.

technical field

The present application relates to the field of communication technologies, and in particular, to a radio frequency power amplifier module.

Background technique

With the rapid development of cellular mobile communication technology, the demand for different systems GSM, CDMA, WCDMA, TD-SCDMA, LTE and NR, to different frequency bands 800MHz to 3800MHz, and to different power levels is increasingly diversified in the market segment. This brings new challenges to the iterative update of mobile communication product development. In the front-end circuit of the transmitter of the communication product, the power of the RF signal generated by the modulation oscillator circuit is very small, and it needs to go through a series of amplification—buffer stage, intermediate amplification stage, and final power amplification stage. After obtaining enough RF power, can be fed to the antenna and radiated out. In order to obtain a sufficiently large RF output power, a RF power amplifier module is used. Therefore, the RF power amplifier module, as an important part of various mobile communication products, has a wide range of applications.

Due to the interweaving of new and old RF power amplifier products, the wide range of product demands and the fast iteration speed of mobile communication products, engineers need to check the requirements of standard, frequency band, power, etc. one by one, and develop RF power amplifier module products that meet various combination requirements. At the same time, it will bring the problems of low material reusability, high cost and long development cycle of RF power amplifier products.

At present, no effective solution has been proposed for the problem of low material reusability of RF power amplifier products in related technologies.

SUMMARY OF THE INVENTION

Embodiments of the present application provide a radio frequency power amplifier module to at least solve the problem of low material reusability of radio frequency power amplifier products in the related art.

In a first aspect, an embodiment of the present application provides a radio frequency power amplifier module, and the functional units of the radio frequency power amplifier module are respectively arranged on a first circuit board and a second circuit board; wherein, the first circuit board includes a first physical connection structure and a second circuit board. an electrical interface, the second circuit board includes a second physical connection structure and a second electrical interface; the functional unit of the radio frequency power amplifier module includes a final-stage power amplifier, and the final-stage power amplifier is arranged on the first circuit board; the first connection structure and the second electrical interface; The second connection structure is used to fix the first circuit board and the second circuit board; the first electrical interface and the second electrical interface are used to provide electrical connection between the first circuit board and the second circuit board.

In some of the embodiments, other functional units of the functional units of the radio frequency power amplifier module except the final stage power amplifier are all disposed on the second circuit board.

In some of the embodiments, the radio frequency power amplifier module further includes: a mounting frame, the mounting frame includes a mounting base for adapting to the first physical connection structure and the second physical connection structure; the first circuit board is fixed to the first physical connection structure through the first physical connection structure. an installation frame, and the second circuit board is fixed to the installation frame through the second physical connection structure.

In some of these embodiments, the second circuit board includes one or more transmission signal conditioning units, wherein the transmission signal conditioning units are used to perform impedance transformation and/or phase conditioning on the transmission signal.

In some of the embodiments, the transmission signal conditioning unit includes multiple groups of pre-configured microstrip lines; the signal transmission lines used for transmitting signals are provided with interruption points, and the multiple groups of pre-configured microstrip lines are set at the interruption points, and are pre-configured. A gap exists between the input end and the output end of the configured microstrip line and the two ends formed by the interruption point of the signal transmission line, respectively.

In some of these embodiments, the transmission signal conditioning unit includes a plurality of preconfigured microstrip line units, wherein the plurality of microstrip line units includes a first microstrip line unit and a second microstrip line unit; There is an interruption point on the signal transmission line, the first microstrip line unit is arranged at the interruption point, and the input end and the output end of the first microstrip line unit respectively have a gap with the two ends formed by the interruption point of the signal transmission line; The two microstrip line units are arranged on the side of the first microstrip line unit relatively far from the signal transmission line, and the input end and the output end of the second microstrip line unit respectively exist with the two ends provided by the first microstrip line unit gap.

In some of the embodiments, the microstrip line unit includes a U-shaped microstrip line, the two ends of the U-shaped microstrip line are the input end and the output end of the microstrip line unit, and the first microstrip line unit is in the U-shaped microstrip line. Two ends are provided on both sides of the bottom of the microstrip line, and the input end and the output end of the second microstrip line unit respectively exist with the two ends provided on both sides of the bottom of the U-shaped microstrip line of the first microstrip line unit Gap; wherein, the bottom of the U-shaped microstrip line has no interruption point or has an interruption point.

In some of these embodiments, one or more standardized interfaces are provided on the second circuit board, each standardized interface for connecting a pin-compatible radio frequency filter, circulator, or coupler.

In some of the embodiments, the radio frequency power amplifier module includes a coupler, the coupler is disposed on the second circuit board, and the coupler is used for coupling the output signal of the final stage power amplifier; wherein, the coupler is a microstrip line coupler.

In some of the embodiments, the radio frequency power amplifier module includes a digital predistortion module and an analog predistortion module, wherein the digital predistortion module and the analog predistortion module are both disposed on the second circuit board.

Compared with the related art, in the radio frequency power amplifier module provided by the embodiments of the present application, a first circuit board and a second circuit board are respectively arranged in the functional units of the radio frequency power amplifier module; wherein, the first circuit board includes a first physical connection structure and The first electrical interface, the second circuit board includes a second physical connection structure and a second electrical interface; the functional unit of the radio frequency power amplifier module includes a final stage power amplifier, and the final stage power amplifier is arranged on the first circuit board; the first connection structure and The second connection structure is used to fix the first circuit board and the second circuit board; the first electrical interface and the second electrical interface are used to provide electrical connection between the first circuit board and the second circuit board, which solves the problem of RF power amplifier products. The problem of low material reusability reduces the cost of RF power amplifier products, shortens the development cycle, and eases the pressure on supply chain storage.

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

The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application. In the attached image:

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

2 is a schematic structural diagram of a U-shaped microstrip line according to an embodiment of the present application;

3 is a schematic structural diagram of a radio frequency power amplifier module according to an optional embodiment of the present application;

4 is a schematic structural diagram of a U-shaped microstrip line according to an optional embodiment of the present application;

5 is a schematic structural diagram in a DPD mode in a TDD system according to an optional embodiment of the present application;

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

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

FIG. 8 is a schematic diagram of separation of a PCB board of a final stage power amplifier from a main control board according to an optional embodiment of the present application.

Detailed ways

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 terms or scientific terms involved in this application shall have the ordinary 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 radio frequency power amplifier module provided in this embodiment may be integrated in a base station, a radio remote unit (Radio Remote Unit, RRU for short), or any other network element device that needs to perform radio frequency transmission and reception. A base station herein 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:

The microstrip line is a printed wire separated by a dielectric on the ground layer. It is a strip conductor (signal line) and is separated from the ground plane by a dielectric. The thickness, width, The distance between the trace and the ground layer and the dielectric constant of the dielectric determine the characteristic impedance of the microstrip line. If the thickness, width, and distance from the ground plane of the line are controllable, its characteristic impedance is also controllable. The propagation delay time per unit length of microstrip line depends only on the dielectric constant and has nothing to do with the line width or spacing.

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. , to compensate AM-AM (amplitude distortion) and AM-PM (phase distortion) generated by nonlinear power amplifier components, and finally make the input and output of the entire predistortion 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.

Time Division Duplexing: Time Division Duplexing (TDD), the transceiver shares a radio frequency point, and the uplink and downlink use different time slots for communication.

Frequency Division Duplexing: Frequency Division Duplexing (FDD), which uses different radio frequency frequencies to communicate.

pin to pin: refers to the same functional pins of the chip, and the chips can be interchanged.

This embodiment provides a radio frequency power amplifier module. FIG. 1 is a schematic structural diagram of a radio frequency power amplifier module according to an embodiment of the present application. As shown in FIG. 1, the radio frequency power amplifier module includes: a first circuit board 200, a second circuit board 100, The final stage power amplifier 201 , the first physical connection structure 203 , the first electrical interface 202 , the second physical connection structure 106 , the second electrical interface 105 , the transmission signal conditioning unit 103 and the mounting frame 300 . The first circuit board 200 includes a first physical connection structure 203 and a first electrical interface 202, the second circuit board 100 includes a second physical connection structure 106 and a second electrical interface 105; the functional unit of the radio frequency power amplifier module includes the final stage power The amplifier 201 and the final power amplifier 201 are arranged on the first circuit board 200; the first physical connection structure 203 and the second physical connection structure 106 are used to fix the first circuit board 200 and the second circuit board 100; the first electrical interface 202 And the second electrical interface 105 is used to provide electrical connection between the first circuit board 200 and the second circuit board 100 .

In this embodiment, other functional units except the final stage power amplifier 201 in the functional units of the radio frequency power amplifier module are all disposed on the second circuit board 100 .

In this embodiment, the radio frequency power amplifier module further includes: a mounting frame 300, the mounting frame 300 includes a mounting base 301 for adapting the first physical connection structure 203 and the second physical connection structure 106; the first circuit board 200 passes through the first physical connection structure 203 and the second physical connection structure 106. The physical connection structure 203 is fixed to the installation frame 300 , and the second circuit board 100 is fixed to the installation frame 300 through the second physical connection structure 106 .

In this embodiment, the second circuit board 100 includes one or more transmission signal conditioning units 103 , wherein the transmission signal conditioning units 103 are used to perform impedance transformation and/or phase adjustment on the transmission signal.

In some optional implementation manners, the position and number of the signal adjustment units 103 in the second circuit board 100 are not fixed, and can be optionally placed between the first gain adjustment unit 101 and the predistortion unit 102, and the first gain adjustment unit Before 101 , between the predistortion unit 102 and the transmission signal conditioning unit 103 and/or after the transmission signal conditioning unit 103 . In the above manner, impedance transformation and/or phase adjustment of the transmission signal is performed by adding a signal conditioning unit.

In this embodiment, the transmission signal adjustment unit 103 includes multiple groups of preconfigured microstrip lines; the signal transmission lines used for transmitting signals are provided with interruption points, and the multiple groups of preconfigured microstrip lines are set at the interruption points, and are pre-configured. A gap exists between the input end and the output end of the configured microstrip line and the two ends formed by the interruption point of the signal transmission line, respectively. Different microstrip line lengths are obtained by filling conductors at the gaps, and different carrier frequencies and carrier wavelengths are supported to pass through the transmission signal adjustment unit 103 .

In this embodiment, the transmission signal conditioning unit 103 includes a plurality of pre-configured microstrip line units, wherein the plurality of microstrip line units include a first microstrip line unit and a second microstrip line unit; There is an interruption point on the signal transmission line, the first microstrip line unit is arranged at the interruption point, and the input end and the output end of the first microstrip line unit respectively have a gap with the two ends formed by the interruption point of the signal transmission line; The two microstrip line units are arranged on the side of the first microstrip line unit relatively far from the signal transmission line, and the input end and the output end of the second microstrip line unit respectively exist with the two ends provided by the first microstrip line unit gap. The first microstrip line is obtained by filling the gap formed between the first microstrip line unit and the two ends of the signal transmission line, and the first microstrip line is obtained by filling the gap formed between the second microstrip line unit and the two ends of the first microstrip line unit. Two microstrip lines, the first microstrip line and the second microstrip line can support transmission signals through different carrier frequencies and carrier wavelengths.

In one of the optional embodiments, the microstrip line unit includes a U-shaped microstrip line. The schematic diagram of the structure of the U-shaped microstrip line is shown in FIG. 2 . The two ends of the U-shaped microstrip line are respectively the microstrip line unit. The first microstrip line unit provides two terminals on both sides of the bottom of the U-shaped microstrip line, and the input and output ends of the second microstrip line unit are respectively connected with the first microstrip line unit. There are gaps between the two ends provided on both sides of the bottom of the U-shaped microstrip line; wherein, the bottom of the U-shaped microstrip line has no interruption point or has an interruption point. The first U-shaped microstrip line is obtained by filling the gap formed by the U-shaped microstrip line of the first microstrip line unit and the two ends of the signal transmission line, and the U-shaped microstrip line of the second microstrip line unit is filled with the first U-shaped microstrip line. The gap formed by the two ends of the U-shaped microstrip line of the microstrip line unit is the second U-shaped microstrip line. The first U-shaped microstrip line and the second U-shaped microstrip line can support different carrier frequencies and The transmitted signal at the carrier wavelength.

In this embodiment, one or more standardized interfaces are provided on the second circuit board 100, and each standardized interface is used to connect the pin-compatible first gain adjustment unit 101, predistortion unit 102, primary power amplification unit 104 and feedback Unit 107, the first gain adjustment unit 101 includes a radio frequency filter, the feedback unit 107 includes a circulator and a coupler, the coupler is arranged on the second circuit board 100, and the coupler is used for coupling the output signal of the final stage power amplifier; wherein, the coupling The coupler is a microstrip line coupler. In the above manner, it is possible to support the coupling of signals when high-power signals pass through.

In an optional embodiment, the predistortion unit 102 includes a digital predistortion module and an analog predistortion module, wherein the digital predistortion module and the analog predistortion module are both disposed on the second circuit board 100 . The digital predistortion module is implemented by an integrated digital processing chip. The integrated digital processing chip is equipped with a DSP function block, which can realize DPD correction. In some cases, the integrated digital processing chip does not support DPD correction in the private network frequency band. Therefore, In the embodiment of the application, for a private network product in a special private network frequency band, the signal correction needs to be realized through the APD function, so that the output linearity that meets the product requirements can be obtained. The embodiment of the present application also realizes the narrowband signal correction through the APD function, which is used to solve the problem that the correction effect of the narrowband signal whose processing frequency is within the range of 200KHz to 5MHz by the DPD algorithm is not ideal.

FIG. 3 is a schematic structural diagram of a radio frequency power amplifier module according to an optional embodiment of the present application. As shown in FIG. 3 , in this embodiment, the second circuit board 100 is a main control board, and FIG. 8 is a final stage according to an optional embodiment of the present application. A schematic diagram of the separation of the PCB board of the power amplifier from the main control board, wherein 401 is the final stage power amplifier PCB board, and 402 is the main control board. The radio frequency power amplifier module further includes a second gain adjustment unit 109, the first gain adjustment unit 101 includes a radio frequency filter 18 and a digitally controlled attenuator 19; the predistortion unit 102 includes a microwave capacitor 11, a microwave capacitor 12, a microwave capacitor 13, a microwave capacitor 14, Microstrip delay line 15, directional coupler 16, directional coupler 17 and APD chip 110; feedback unit 107 includes microwave coupler 113, circulator 114, microwave switch 115 and load resistor 116, wherein microwave switch 115 includes 1, 2 and 3 ports. Through the above method, in the design of high-power RF power amplifier platform, flexible development and design are carried out by splitting a small part of the final stage power amplifier circuit. In the main control board, a large number of ultra-wideband RF chips are used for selection and package size. The passive frequency device design of the feet realizes the multi-standard, multi-band and multi-power level RF power amplifier requirements on the RF power amplifier technology platform to achieve a common PCB board and a common modular design, which greatly improves the material reuse of high-power RF power amplifier products. It can reduce the development cycle and cost, and ease the pressure on the supply chain storage.

In this embodiment, the downlink signal is connected to the downlink signal input port TX_IN. After the gain is adjusted by the radio frequency filter 18 and the numerically controlled attenuator 19, the microwave capacitor 11 and the microwave capacitor 12 are selected to enter the DPD mode, and the microwave capacitor 13 is selected to be welded. and microwave capacitor 14 into APD mode. In the above manner, the predistortion unit 102 adopts the coexistence of analog predistortion APD and digital predistortion DPD, with DPD as the main component to reduce costs, and APD as the auxiliary component to improve the adaptability of the predistortion scheme. APD has a strong ability to correct narrowband signals, and supplements the application scenarios where DPD is not competent. For example, in signal application scenarios such as GSM and NB-IOT with a single carrier bandwidth of 200K, and some private network frequency band applications that DPD cannot support, welding microwave capacitors are used in sampling signal input, correction signal output and feedback signal channels to reduce predistortion. Switch to APD mode.

In this embodiment, after impedance conversion and/or phase adjustment performed by the transmission signal adjustment unit 103, the signal is amplified by the primary power amplifying unit 104 and the final power amplifier 201 of the downlink main channel to reach the required power level, and then passes through the ring TDD and FDD systems can be switched through the selection of microwave switch 115, microwave capacitor 117 and microwave capacitor 118; in TDD mode, microwave switch 115 is connected to ports 1 and 3, and the downstream reflected signal is composed of The load resistor 116 receives; and when the microwave switch 115 is connected to ports 1 and 2, the upstream signal is connected to the upstream signal input port ANT, and the microwave capacitor 117 is selectively welded through the circulator 114. At this time, the signal is connected to the upstream main channel, and passes through the second After the gain adjustment unit 109 adjusts the signal gain, it reaches the upstream signal output port RX_OUT; and in the FDD mode, on the one hand, the microwave switch 115 is kept connected to ports 1 and 3, the downstream reflected signal is received by the load resistor 116, and the upstream signal is received by the load resistor 116. The upstream signal input port RX_IN is connected. After the microwave capacitor 118 is selected and welded, the signal is connected to the upstream main channel. In this embodiment, the feedback signal required for predistortion is collected by the microstrip directional coupler 115. If the microwave capacitor 111 is selected to be welded, the signal reaches the DPD feedback signal output port FB_DPD, and the signal will be connected to the external digital board DPD function module at this time. In; if the microwave capacitor 112 is selected to be welded, the signal is connected to the feedback port FB_APD of the APD chip. In the above manner, in the uplink receiving link, the microwave switch 115 is used as a mode switching device to adjust the direction of the uplink signal on the TDD link and the FDD link.

It should be noted that, in the embodiments of the present application, the main control unit 119 includes, but is not limited to, one of the following: a single-chip microcomputer, a PFGA, and a DSP.

It should be noted that, in this embodiment, the primary power amplifying unit 104 and the final power amplifier 201 constitute a radio frequency amplifier, and the radio frequency amplifier includes but is not limited to a Doherty amplifier. At the same time, in this embodiment, the predistortion system 102 performs predistortion processing on the input RF power amplifier signals of different signal frequencies and signal bandwidths, and then amplifies them through the cascaded RF amplifiers. Compensate the nonlinear distortion of the radio frequency amplifier, make the input and output of the radio frequency amplifier present a linear relationship, and make the radio frequency amplifier adapt to the modulation of multi-band and multi-system.

In this embodiment, the main control unit 119 is connected to the predistortion unit 102 through SPI serial communication.

In this embodiment, the transmission signal conditioning unit 103 includes a plurality of pre-configured microstrip line units, and the microstrip line units include U-shaped microstrip lines. The schematic structural diagram of the U-shaped microstrip line is shown in FIG. 2 . The two ends of the strip line are respectively the input end and the output end of the microstrip line unit. The first microstrip line unit provides two ends on both sides of the bottom of the U-shaped microstrip line. The input end of the second microstrip line unit The terminal and the output terminal respectively have gaps with two terminals provided on both sides of the bottom of the U-shaped microstrip line of the first microstrip line unit; wherein the bottom of the U-shaped microstrip line has no interruption point or has an interruption point. The first U-shaped microstrip line is obtained by filling the gap formed by the U-shaped microstrip line of the first microstrip line unit and the two ends of the signal transmission line, and the U-shaped microstrip line of the second microstrip line unit is filled with the first U-shaped microstrip line. The gap formed by the two ends of the U-shaped microstrip line of the microstrip line unit is the second U-shaped microstrip line. The first U-shaped microstrip line and the second U-shaped microstrip line can support different carrier frequencies and The transmitted signal at the carrier wavelength.

In this embodiment, in the second circuit board 100 , that is, in the main control board PCB, since the same PCB board needs to be used at different frequencies, the design problem of the radio frequency microstrip line with different frequencies is introduced. According to the line theory, the characteristic impedance formula of the RF microstrip line at different frequencies is as follows:

Among them, Z ₀ is the characteristic impedance of the printed circuit board microstrip line, ε _r is the dielectric constant of the insulating material, h is the distance between the printed circuit board microstrip line and the reference plane, and w is the printed circuit board microstrip line. width, t is the thickness of the printed circuit board microstrip line.

It can be found from the above formula that when the signal is transmitted on the microstrip line on the printed circuit board, the width of the microstrip line etched on the printed circuit board is not related to the carrier frequency of the transmitted signal. When the characteristic impedance of the radio frequency microstrip line is one Timing, the width of the microstrip line is determined by the PCB board and the board making process, which provides a theoretical basis for the common use of products with different frequencies on the main control board. Therefore, in this embodiment, the microstrip line on the main control board PCB is 50Ω. Characteristic impedance uniformly uses 1.1mm width microstrip line at different frequencies.

In addition, in the PCB design of the main control board, in some environments, such as the impedance conversion of the microstrip line or the adjustment of the phase of the transmission signal, the influence of the signal frequency and wavelength on the length of the microstrip line needs to be considered. At a specific frequency, a 1/4 wavelength microstrip line is required to be etched on the PCB board. At this time, it involves the need to etch microstrip lines of different lengths in the PCB at different frequencies. The formula of frequency and wavelength as follows:

Among them, λ is the wavelength of the carrier wave in the printed circuit board, C is the propagation speed of the microwave in a vacuum state, and ε _r is the dielectric constant of the insulating material. It can be found from the above formula that in the same printed circuit board, the carrier wave wavelength It is inversely proportional to the carrier frequency. When designing microstrip lines with different frequencies and special wavelength requirements, the corresponding lengths of the microstrip lines that need to be etched in the PCB are different. At this time, it is necessary to adopt a PCB layout compatible design method. .

In this embodiment, according to the above formula of frequency and wavelength, when a 1/4λ wavelength microstrip line is required, the length of the microstrip line to be etched at 0.9GHz, 1.8GHz, 2.6GHz and 3.5GHz is 21mm, 10.5mm, 7.27mm and 5.4mm, the corresponding 1/4λ wavelength microstrip line etching in the PCB is shown in schematic diagram 4, using conductors to fill gaps 27 and 28 to obtain 3.5GHz microstrip lines, using conductors to fill gaps 25, 26, 31 and 32 to get a 2.6GHz microstrip line, using conductors to fill gaps 25, 26, 21, 22, 33, and 34, to get a 1.8GHz microstrip line, using conductors to fill gaps 25, 26, 21, 22, 23, and 24, A 0.9GHz microstrip line is obtained. Through the above methods, microstrip lines suitable for different frequencies can be designed, which enhances the usability of the common board design of the main control board and PCB, and provides a theoretical guarantee for adapting to more product requirements.

An embodiment of the present application provides a DPD mode in a TDD system, and FIG. 5 is a schematic structural diagram in a DPD mode in a TDD system according to an embodiment of the present application. In the TDD system in the DPD mode, the downstream signal is connected to the main channel of the downstream signal after the microwave capacitor 11 and the microwave capacitor 12 are selectively welded, while the upstream signal is connected to the upstream signal input port ANT, and is connected to the port through the circulator and the microwave switch 115 After 1 and 2, the microwave capacitor 117 is selected to be welded and connected to the main channel of the upstream signal. After the DPD feedback signal is collected by the microstrip directional coupler 113, the microwave capacitor 111 is selected to be welded and reaches the DPD feedback signal output port FB_DPD. Access to the external digital board DPD function module.

An embodiment of the present application provides an APD mode in a TDD system, and FIG. 6 is a schematic structural diagram of an APD mode in a TDD system according to an embodiment of the present application. In the TDD system in the APD mode, after the downlink signal is selectively welded to the microwave capacitor 13, after the 0-4ns microstrip delay line 15, the microwave capacitor 14 is selectively welded back to the main channel of the downlink signal, wherein the APD input correction signal is coupled by the directional coupling After the APD feedback signal is collected by the microstrip directional coupler 113, the microwave capacitor 112 is selected to be welded, and the APD feedback signal input port FB_APD is connected to the APD feedback signal input port FB_APD. Inside the APD chip.

An embodiment of the present application provides an FDD system, and FIG. 7 is a schematic structural diagram of an FDD system according to an embodiment of the present application. In the DPD mode of the FDD system, keep the microwave switch 115 connected to ports 1 and 3, the downstream reflected signal is received by the load resistor 116, and the upstream signal is connected to the upstream signal input port RX_IN, and the microwave capacitor 118 is selected to be welded. At this time, the signal passes through the second After the gain adjustment unit 109 adjusts the signal gain, it reaches the uplink signal output port RX_OUT.

Those skilled in the art should understand that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, 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-mentioned embodiments 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 patent application. 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 (10)

1. A radio frequency power amplifier module, characterized in that the functional units of the radio frequency power amplifier module are respectively arranged on a first circuit board and a second circuit board; wherein, the first circuit board includes a first physical connection structure and a first electrical an interface, the second circuit board includes a second physical connection structure and a second electrical interface; the functional unit of the radio frequency power amplifier module includes a final-stage power amplifier, and the final-stage power amplifier is arranged on the first circuit board; The first physical connection structure and the second physical connection structure are used to fix the first circuit board and the second circuit board; the first electrical interface and the second electrical interface are used to provide the Electrical connection between the first circuit board and the second circuit board.
2. The radio frequency power amplifier module according to claim 1, wherein other functional units in the functional units of the radio frequency power amplifier module except the last stage power amplifier are all disposed on the second circuit board.
3. The radio frequency power amplifier module according to claim 1, wherein the radio frequency power amplifier module further comprises: a mounting frame, the mounting frame comprising a mounting for adapting the first physical connection structure and the second physical connection structure a base; the first circuit board is fixed to the installation frame through the first physical connection structure, and the second circuit board is fixed to the installation frame through the second physical connection structure.
4. The radio frequency power amplifier module according to claim 1, wherein the second circuit board comprises one or more transmission signal conditioning units, wherein the transmission signal conditioning units are used to perform impedance conversion and/or phase adjustment on the transmission signal .
5. The radio frequency power amplifier module according to claim 4, wherein the transmission signal adjustment unit comprises a plurality of groups of preconfigured microstrip lines; the signal transmission line used for transmitting signals is provided with an interruption point, and the plurality of groups of the preconfigured microstrip lines are provided with an interruption point. The strip line is set at the interruption point, and the input end and the output end of the preconfigured microstrip line respectively have a gap with the two ends formed by the interruption point of the signal transmission line.
6. The radio frequency power amplifier module according to claim 4, wherein the transmission signal conditioning unit comprises a plurality of pre-configured microstrip line units, wherein the plurality of microstrip line units comprises a first microstrip line unit and a second microstrip line unit A microstrip line unit; an interruption point is provided on the signal transmission line for transmitting signals, the first microstrip line unit is set at the interruption point, and the input end and the output end of the first microstrip line unit are respectively There is a gap with the two ends formed by the interruption point of the signal transmission line; the second microstrip line unit is arranged on a side of the first microstrip line unit relatively far away from the signal transmission line, and the first microstrip line unit There are gaps between the input end and the output end of the two microstrip line units and the two ends provided by the first microstrip line unit, respectively.
7. The radio frequency power amplifier module according to claim 6, wherein the microstrip line unit comprises a U-shaped microstrip line, and two ends of the U-shaped microstrip line are the input end and the input end of the microstrip line unit, respectively. The output end, the first microstrip line unit provides two ends on both sides of the bottom of the U-shaped microstrip line, and the input end and the output end of the second microstrip line unit are respectively connected with the first microstrip line unit. There are gaps between two ends provided on both sides of the bottom of the U-shaped microstrip line of the strip line unit; wherein, the bottom of the U-shaped microstrip line has no interruption point or has an interruption point.
8. The radio frequency power amplifier module according to claim 1, wherein one or more standardized interfaces are provided on the second circuit board, and each of the standardized interfaces is used to connect a pin-compatible radio frequency filter, circulator or coupler .
9. The radio frequency power amplifier module according to claim 1, wherein the radio frequency power amplifier module comprises a coupler, the coupler is arranged on the second circuit board, and the coupler is used for coupling the output of the final stage power amplifier signal; wherein, the coupler is a microstrip line coupler.
10. The radio frequency power amplifier module according to claim 1, wherein the radio frequency power amplifier module comprises a digital predistortion module and an analog predistortion module, wherein the digital predistortion module and the analog predistortion module are both arranged in the first Second circuit board.

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