WO2022041286A1 - 一种Doherty功率放大器、印刷电路板及基站 - Google Patents

一种Doherty功率放大器、印刷电路板及基站 Download PDF

Info

Publication number
WO2022041286A1
WO2022041286A1 PCT/CN2020/112739 CN2020112739W WO2022041286A1 WO 2022041286 A1 WO2022041286 A1 WO 2022041286A1 CN 2020112739 W CN2020112739 W CN 2020112739W WO 2022041286 A1 WO2022041286 A1 WO 2022041286A1
Authority
WO
WIPO (PCT)
Prior art keywords
power amplifier
network
coupler
frequency band
phase compensation
Prior art date
Application number
PCT/CN2020/112739
Other languages
English (en)
French (fr)
Inventor
陈金虎
索海雷
孙益军
孙捷
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to PCT/CN2020/112739 priority Critical patent/WO2022041286A1/zh
Publication of WO2022041286A1 publication Critical patent/WO2022041286A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
    • H03F1/04—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in discharge-tube amplifiers
    • H03F1/06—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in discharge-tube amplifiers to raise the efficiency of amplifying modulated radio frequency waves; to raise the efficiency of amplifiers acting also as modulators
    • H03F1/07—Doherty-type amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers

Definitions

  • the present application relates to the field of communication technologies, and in particular, to a Doherty power amplifier, a printed circuit board and a base station.
  • Bandwidth expansion is a distinctive feature of wireless communication evolution, including more frequency division of frequency spectrum and wider signal bandwidth to support larger data transmission rate and data capacity.
  • the current wireless communication system is compatible with multiple wireless communication standards, and each wireless communication standard involves multiple operating frequency bands. Therefore, the frequency bands used by the wireless communication system are relatively fragmented and the frequency band is wider and wider. In order to meet the needs of various operators around the world, this also requires the developed wireless communication system to have the characteristics of broadband and multi-band, support multi-mode and multi-band, and the radio frequency module in the network equipment in the wireless communication system needs to have a mixture of low, medium and high RF capability of the frequency band.
  • the RF module can contain multiple power amplifiers ranging from 700/800/900MHz, 1800MHz, 2100MHz, 2600MHz to 3.5/4.9/5.8GHz.
  • the Doherty power amplifier is based on the principle of active load modulation, which can effectively improve the fallback efficiency, thereby improving the efficiency of the power amplifier, and has been widely used in network equipment.
  • Figure 1 shows the working principle diagram of the Doherty power amplifier
  • Figure 2 shows the efficiency curve diagram of the Doherty power amplifier.
  • the design core of the broadband and multi-frequency Doherty power amplifier lies in the broadband and multi-frequency characteristics that the input and output network needs to have.
  • Figure 3 shows a structure of a dual-frequency Doherty power amplifier in the prior art.
  • Frequency power division network, dual-frequency phase compensation network, dual-frequency impedance inverter network, and dual-frequency impedance transformation network are replaced to realize the design of dual-frequency Doherty.
  • it can only work in two frequency bands.
  • the power amplifier needs to work in more frequency bands, it needs to use a multi-band power division network, a phase compensation network, an impedance inverter network, and an impedance transformation network to replace each part, and Its power amplifier is not reconfigurable.
  • FIG. 4 shows a structure of a coupler-based Doherty power amplifier in the prior art, which is mainly used to adjust the short-circuit or open-circuit of the second output port of the coupler to realize the pulling characteristic of the Doherty power amplifier.
  • its working bandwidth is limited, it is difficult to take into account multiple frequency bands such as low frequency 700MHz, 800MHz, 900MHz and high frequency 3.5GHz, 5.8GHz, and it does not have reconfigurable characteristics.
  • the Doherty power amplifier in the prior art can achieve traction characteristics in multiple frequency bands, the structure is complex and does not have reconfigurable characteristics.
  • the present application provides a Doherty power amplifier, a printed circuit board and a base station, which are used to realize the traction characteristics of the Doherty power amplifier in multiple frequency bands, and have a simple structure and reconfigurable characteristics.
  • an embodiment of the present application provides a Doherty power amplifier, including:
  • a power amplifier unit including a first power amplifier and a second power amplifier, for respectively receiving input signals and performing power amplification processing on the input signals, wherein the first power amplifier is configured as a main power amplifier or an auxiliary power amplifier, and the second power amplifier is configured as a main power amplifier or an auxiliary power amplifier.
  • the power amplifier is configured as a main power amplifier and an auxiliary power amplifier of a different power amplifier type from the first power amplifier, and the auxiliary power amplifier performs active load pulling with the main power amplifier based on working states of different power input signals;
  • a combining unit including a first matching network, a second matching network, a coupler and a phase compensation network, for performing impedance matching when the Doherty power amplifier is located at a back-off point and a full power point, wherein the first matching The network or the second matching network and the phase compensation network satisfy a preset phase relationship;
  • the first matching network is configured to receive the amplified signal sent by the main power amplifier and input to the coupler
  • the second matching network is configured to receive the amplified signal sent by the auxiliary power amplifier and input to the coupler
  • the coupler configured to perform power synthesis on the amplified signal output by the main power amplifier and the amplified signal output by the auxiliary power amplifier, and send them to the impedance transformation network;
  • the phase compensation network configured to form the preset phase relationship based on a working frequency band of the Doherty power amplifier, wherein the working frequency band is at least one frequency band;
  • the impedance transformation network is connected to the rear-stage load, and is used for transforming the characteristic impedance of the Doherty power amplifier to an impedance matching the rear-stage load.
  • the Doherty power amplifier provided by the embodiment of the present invention includes a main power amplifier, an auxiliary power amplifier, a first matching network, a second matching network, a coupler, a phase compensation network, and an impedance transformation network, wherein the main power amplifier and the auxiliary power amplifier are used to convert the input signal into Power amplification, the auxiliary power amplifier performs active load pulling with the main power amplifier based on the working state of different power input signals; the coupler combines the matching unit and the phase compensation network that meet a certain phase relationship to complete the dual power impedance matching, that is, the Doherty power
  • the impedance of the amplifier at the back-off point and the impedance of the Doherty power amplifier at full power are matched to the characteristic impedance.
  • the amplified signals of the main power amplifier and the auxiliary power amplifier are power-combined through the coupler, and output to the impedance transformation network.
  • the transformation network transforms the characteristic impedance to the load impedance.
  • the characteristic impedance of the coupler is Z0, which satisfies the following formula:
  • R opt is the impedance of the main power amplifier biased under class B
  • V dd is the drain operating voltage of the main power amplifier
  • V knee is the knee voltage of the main power amplifier
  • P sat is the main power amplifier the saturated output power.
  • the characteristic impedance of the coupler is based on the above formula, and is optimized according to the impedance of the main power amplifier (auxiliary power amplifier) biased under class B, that is, the optimal impedance R opt , to determine the characteristic impedance Z0, To achieve optimal RF performance of Doherty power amplifiers.
  • the second output end of the coupler is connected to the phase compensation network, and the first output end of the coupler is connected to the impedance transformation network;
  • the first power amplifier is configured as a main power amplifier, and the second power amplifier is configured as an auxiliary power amplifier;
  • the first power amplifier is configured as an auxiliary power amplifier
  • the second power amplifier is configured as a main power amplifier
  • the first output end of the coupler is connected to the phase compensation network, and the second output end of the coupler is connected to the impedance transformation network;
  • the first power amplifier is configured as a main power amplifier, and the second power amplifier is configured as an auxiliary power amplifier;
  • the first power amplifier is configured as an auxiliary power amplifier
  • the second power amplifier is configured as a main power amplifier
  • the first preset frequency band, the second preset frequency band, the third preset frequency band, and the fourth preset frequency band are all different frequency bands.
  • the Doherty power amplifier by reasonably selecting the output port, switching the phase compensation network and the impedance transformation network, and combining the different configurations of the first power amplifier and the second power amplifier, the Doherty power amplifier can design various schemes, Achieve multi-frequency reconfigurability of Doherty power amplifiers.
  • the working frequency band is the first preset frequency band and/or the fourth preset frequency band:
  • the first matching network and the second matching network are the same network, and the network is equivalent to a microstrip network with characteristic impedance Z0 and phase ⁇ 1;
  • the phase compensation network is equivalent to a microstrip network with characteristic impedance Z0 and phase ⁇ 2, where ⁇ 2 is the phase angle corresponding to the first preset frequency band and/or the fourth preset frequency band, and the ⁇ 1 and ⁇ 2
  • ⁇ 2 is the phase angle corresponding to the first preset frequency band and/or the fourth preset frequency band
  • the set working frequency band is the second preset frequency band and/or the third preset frequency band:
  • the first matching network and the second matching network are the same network, and the network is equivalent to a microstrip network with characteristic impedance Z0 and phase ⁇ 1;
  • the phase compensation network is equivalent to a microstrip network with characteristic impedance Z0 and phase ⁇ 2, where ⁇ 2 is the phase angle corresponding to the second preset frequency band and/or the third preset frequency band, and the ⁇ 1 and ⁇ 2
  • ⁇ 2 is the phase angle corresponding to the second preset frequency band and/or the third preset frequency band
  • the Doherty power amplifier provided by the embodiment of the present invention only needs to design a phase compensation network to satisfy one of the above-mentioned two phase relationships, and configure the corresponding positions of the main power amplifier and the auxiliary power amplifier under different working frequency bands.
  • the main power amplifier is a class AB or class B power amplifier
  • the auxiliary power amplifier is a class C power amplifier.
  • the embodiments of the present application provide a printed circuit board, including the Doherty power amplifier described in the first aspect of the embodiments of the present application.
  • an embodiment of the present application provides a printed circuit board, which includes the following structures:
  • a first power amplifier a second power amplifier, a first matching network, a second matching network, a coupler, a first phase compensation network, a second phase compensation network, a first impedance transformation network, and a second impedance transformation network;
  • the output end of the first power amplifier is connected to the input end of the first matching network
  • the output end of the second power amplifier is connected to the input end of the second matching network
  • the output end of the first matching network The terminal is connected to the first input terminal of the coupler, and the output terminal of the second matching network is connected to the second input terminal of the coupler;
  • the circuit board also includes:
  • the printed circuit board provided by the embodiment of the present application reflects all possible circuit structures. When using it, the output port is reasonably selected, and the DC isolation is configured at the first and fourth soldering points or the second and third soldering points. Capacitor, switching the phase compensation network and impedance transformation network, combined with the different configurations of the main power amplifier and the auxiliary power amplifier, make one printed circuit board compatible with multiple working frequency bands, realize the multi-frequency reconfigurability of the Doherty power amplifier, and at the same time No additional insertion loss is introduced, making the RF performance of the circuit better.
  • the embodiments of the present application provide another printed circuit board, which includes the following structure:
  • a first power amplifier a second power amplifier, a first matching network, a second matching network, a coupler, a first phase compensation network, a second phase compensation network, a first impedance transformation network, and a second impedance transformation network;
  • the output end of the first power amplifier is connected to the input end of the first matching network, the output end of the second power amplifier is connected to the input end of the second matching network, and the output end of the first matching network
  • the terminal is connected to the first input terminal of the coupler, the output terminal of the second matching network is connected to the second input terminal of the coupler, and the second output terminal of the coupler is connected to the first phase compensation network.
  • the first output terminal is connected to the second phase compensation network;
  • the circuit board also includes:
  • the printed circuit board provided by the embodiment of the present application reflects all possible circuit structures. When using it, the output port is reasonably selected, and the DC blocking capacitor is configured at the fifth or sixth welding point.
  • the compensation network and the impedance transformation network are switched, combined with the different configurations of the main power amplifier and the auxiliary power amplifier, so that one printed circuit board can be compatible with multiple working frequency bands, and realize the multi-frequency reconfigurability of the Doherty power amplifier without introducing additional
  • the insertion loss of the circuit makes the RF performance of the circuit better.
  • an embodiment of the present application provides a base station, including the Doherty power amplifier described in the first aspect of the embodiment of the present application.
  • 1 is a schematic structural diagram of a Doherty power amplifier provided in the prior art
  • Fig. 2 is the working efficiency curve diagram of a kind of Doherty power amplifier provided in the prior art
  • FIG. 3 is a schematic structural diagram of a dual-frequency Doherty power amplifier provided in the prior art
  • FIG. 4 is a schematic structural diagram of a coupler-based Doherty power amplifier provided in the prior art
  • FIG. 5 is a schematic structural diagram of a small cell radio frequency module according to an embodiment of the present application.
  • FIG. 7 is a schematic structural diagram of another Doherty power amplifier provided by an embodiment of the present application.
  • FIG. 8 is a schematic structural diagram of another Doherty power amplifier provided by an embodiment of the present application.
  • FIG. 9 is a schematic structural diagram of yet another Doherty power amplifier provided by an embodiment of the present application.
  • FIG. 10 is a schematic structural diagram of yet another Doherty power amplifier provided by an embodiment of the present application.
  • 11 is an equivalent circuit diagram of a Doherty power amplifier provided by an embodiment of the application.
  • FIG. 13(a) is a graph showing the variation of the working efficiency of a Doherty power amplifier with input voltage according to an embodiment of the present application
  • FIG. 13(b) is a graph showing the variation of the plane current of the current source of the Main circuit and the Peak circuit with the input voltage of a Doherty power amplifier provided in an embodiment of the application;
  • FIG. 13(c) is a graph showing the variation of the plane voltage of the current source of the Main and Peak circuits with the input voltage of a Doherty power amplifier provided in an embodiment of the application;
  • FIG. 13(d) is a graph showing the variation of the current source plane impedance with the input voltage of the Main circuit and the Peak circuit of a Doherty power amplifier according to an embodiment of the present application;
  • FIG. 14 is a schematic structural diagram of a printed circuit board provided by an embodiment of the application.
  • 15 is a schematic structural diagram of another printed circuit board provided by an embodiment of the application.
  • FIG. 16 is a schematic structural diagram of another printed circuit board provided by an embodiment of the present application.
  • FIG. 17 is a schematic structural diagram of still another printed circuit board provided by an embodiment of the application.
  • FIG. 18 is a schematic structural diagram of still another printed circuit board provided by an embodiment of the present application.
  • FIG. 19 is a schematic structural diagram of still another printed circuit board according to an embodiment of the present application.
  • a power amplifier is a functional module in a transmitter that converts a DC signal into an AC signal and amplifies the power of the input signal.
  • the Doherty power amplifier is a power amplifier based on active load modulation technology. Compared with the traditional power amplifier, the Doherty power amplifier can achieve higher efficiency when the power amplifier works backward.
  • Figure 1 exemplarily shows a schematic structural diagram of a Doherty power amplifier, which includes a main power amplifier, an auxiliary power amplifier and an impedance transformation network.
  • a Doherty power amplifier which includes a main power amplifier, an auxiliary power amplifier and an impedance transformation network.
  • the structure of the Doherty power amplifier is simple, and it can effectively improve the fallback efficiency, thereby improving the efficiency of the power amplifier, but its operating bandwidth is limited, and it is difficult to take into account multiple frequency bands such as low frequency 700MHz, 800MHz, 900MHz, high frequency 3.5GHz, 5.8GHz and so on. , and the circuit structure does not have reconfigurable characteristics.
  • FIG. 5 it is a schematic diagram of a radio frequency module of an indoor small station, which includes transmission channels of multiple frequency bands.
  • an embodiment of the present application provides a Doherty power amplifier, so that it has multi-frequency characteristics at the same time, And with reconfigurable characteristics, it can work in multiple frequency bands, satisfy any single frequency configuration of multiple frequency points, and also realize scenarios such as multi-frequency concurrency of some frequency points.
  • an embodiment of the present application provides a Doherty power amplifier, including:
  • a power amplifier unit including a first power amplifier (PA1) and a second power amplifier (PA2), for respectively receiving an input signal, and performing power amplification processing on the input signal to obtain an amplified signal
  • the first power amplifier is configured as a main power amplifier or an auxiliary power amplifier
  • the second power amplifier is configured with a different power amplifier type from the first power amplifier in the main power amplifier and the auxiliary power amplifier
  • the auxiliary power amplifier performs active load pulling with the main power amplifier based on the working state under different power input signals
  • a combining unit includes a first matching network, a second matching network, a coupler and a phase compensation network, and is used for impedance matching when the Doherty power amplifier is located at the back-off point and the full power point, wherein the first matching network or the second matching network The matching network and the phase compensation network satisfy the set phase relationship;
  • the first matching network is used to receive the amplified signal sent by the main power amplifier and input to the coupler
  • the second matching network is used to receive the amplified signal sent by the auxiliary power amplifier and input to the coupler
  • the coupler is used for power synthesis of the amplified signal of the main power amplifier and the amplified signal of the auxiliary power amplifier;
  • phase compensation network for forming a phase relationship with any matching network in the matching unit based on the working frequency band of the Doherty power amplifier, wherein the working frequency band is at least one frequency band;
  • the impedance transformation network is connected to the post-stage load, and is used to transform the characteristic impedance of the Doherty power amplifier to an impedance matching the post-stage load.
  • the second output end of the coupler in the Doherty power amplifier is connected to the phase compensation network, and the first output end of the coupler is connected to the impedance transformation network.
  • the working frequency band is the first preset frequency band f1
  • PA1 is configured as the main power amplifier
  • PA2 is configured as auxiliary power amplifier.
  • the second output end of the coupler in the Doherty power amplifier is connected to the phase compensation network, and the first output end of the coupler is connected to the impedance transformation network.
  • the operating frequency band is the second preset frequency band f2
  • PA1 is configured as an auxiliary power amplifier
  • PA1 is configured as the main power amplifier.
  • the first output end of the coupler in the Doherty power amplifier is connected to the phase compensation network, and the second output end of the coupler is connected to the impedance transformation network.
  • the operating frequency band is the third preset frequency band f3
  • PA1 is configured as the main power amplifier
  • PA2 is configured as auxiliary power amplifier.
  • the first output end of the coupler in the Doherty power amplifier is connected to the phase compensation network, and the second output end of the coupler is connected to the impedance transformation network.
  • the working frequency band is the fourth preset frequency band f4
  • PA1 is configured as an auxiliary power amplifier
  • PA1 is configured as the main power amplifier.
  • the main power amplifier and the auxiliary power amplifier are power amplifier components with the same configuration, and the first matching network and the second matching network are the same network, which are equivalent to the characteristic impedance of Z0 and the phase of ⁇ 1.
  • the strip network, the phase compensation network is equivalent to a microstrip network with characteristic impedance Z0 and phase ⁇ 2, and the characteristic impedance of the coupler is Z0.
  • the characteristic impedance Z0 of the coupler is optimized according to the optimal impedance R opt of the main power amplifier (auxiliary power amplifier) to achieve optimal RF performance, wherein the relationship between Z0 and R opt can be expressed by formula 1:
  • V dd is the drain operating voltage of the main power amplifier (auxiliary power amplifier)
  • V knee is the knee voltage of the main power amplifier (auxiliary power amplifier)
  • P sat is the saturated output power of the main power amplifier (auxiliary power amplifier).
  • the phase compensation network is equivalent to an open line with characteristic impedance Z0 and phase ⁇ 2.
  • the operating frequency band is f1 and/or f4
  • the phase ⁇ 1 of the first matching network (the second matching network)
  • the phase The relationship between the phases ⁇ 2 of the compensation network satisfies Equation 2:
  • the phase compensation network is equivalent to an open line with characteristic impedance Z0 and phase ⁇ 2.
  • the operating frequency band is f2 and/or f3
  • Equation 3 the relationship between the phases ⁇ 2 of the compensation network satisfies Equation 3:
  • the Doherty power amplifier is divided into two circuits during operation, one is the Main (main power amplifier) circuit, the bias state is class AB/B, and the other is the Peak (auxiliary power amplifier) circuit, the bias state is class C, the Doherty power amplifier.
  • the simulation results are shown in Fig. 13, in which Fig. 13(a) is the graph of the working efficiency of the Doherty power amplifier as a function of the input voltage, and Fig. 13(b) is the current source plane current of the Main and Peak circuits of the Doherty power amplifier with the input voltage.
  • Figure 13(c) is the graph of the current source plane voltage of the Main and Peak circuits of the Doherty power amplifier changing with the input voltage
  • Figure 13(d) is the current source plane impedance of the Main and Peak circuits of the Doherty power amplifier Graph of change with input voltage.
  • the variation range of the impedance of the Main circuit is not limited to 50Ohm to 25Ohm, but can also be other variation ranges, such as 50Ohm to 10Ohm, or 75Ohm to 25Ohm; at the same time, the variation range of the impedance of the Peak circuit is not limited to decreasing from infinity to infinity. As small as 25 Ohm, it can also be reduced from infinity to other values, which are not limited in this application.
  • the working area of the Doherty power amplifier can be roughly divided into three stages: a low-power region, a fallback region, and a full-power region. Below in conjunction with Figure 9, the above three stages are described in detail:
  • the bias state of the Peak circuit is Class C
  • the input power is not enough to drive it to work
  • the Peak circuit is in an open-circuit state at this time.
  • the impedance of the Main circuit remains unchanged.
  • the Main circuit enters a saturated state, and the voltage reaches the full swing, realizing the first high power point in the working process of the Doherty power amplifier.
  • the Peak circuit As the input power gradually increases, the Peak circuit is turned on, and active load pull is performed with the Main circuit. At this time, the impedance of the Main circuit gradually decreases, but its voltage is always full swing and remains in a saturated state; at the same time, the impedance of the Peak circuit also gradually decreases. becomes smaller, the voltage gradually increases, but does not reach saturation, so the operating efficiency of the Doherty power amplifier decreases slightly.
  • the input power is further enhanced. Both the Main and Peak circuits reach saturation, and the voltages both reach full swing. At this time, the Doherty power amplifier achieves the second high-power point in the working process.
  • the coupler combines a matching unit and a phase compensation network that satisfy a certain phase relationship to complete dual-power impedance matching, that is, the impedance of the Doherty power amplifier at the back-off point and the impedance of the Doherty power amplifier at full power are matched to the characteristic impedance, At the same time, the power of the amplified signals of the main power amplifier and the auxiliary power amplifier is combined by the coupler and output to the impedance transformation network, and finally the characteristic impedance is transformed into the load impedance by the impedance transformation network.
  • the multi-band Doherty power amplifier provided by the embodiment of the present application may be designed in the following manner:
  • the optimal impedance of the main power amplifier determine the characteristic impedance Z0 of the first matching network, the second matching network, the coupler and the phase compensation network;
  • Second matching network Design a first matching network (second matching network), and determine the phase ⁇ 1 of the first matching network (second matching network) at different operating frequencies;
  • phase ⁇ 1 of the first matching network (the second matching network) and the phase ⁇ 2 of the phase compensation network, combined with the connection method of the phase compensation network, the impedance transformation network and the coupler, configure the properties of the power amplifier components, and determine the main power amplifier. and the position of the auxiliary amplifier.
  • the circuit can satisfy either of the two phase relationships at different frequencies of the input signal, and at the same time, according to the corresponding power amplifier element configuration required by the phase relationship, the pulling effect of the Doherty power amplifier in multiple frequency bands can be achieved.
  • the embodiment of the present application provides a printed circuit board, so that under different power amplifier configurations, the first output end and the second output end of the coupler can be switched in the network to select different output ports as power output in different working frequency bands. It should be noted that when the printed circuit board performs the network switching of the output port, it is realized by the welding of the DC blocking capacitor, and then only the modification of the BOM (Bill of Material, bill of materials) realizes the possibility of the Doherty power amplifier. Refactoring.
  • the printed circuit board provided by the embodiment of the present application includes the following structure:
  • a first power amplifier a second power amplifier, a first matching network, a second matching network, a coupler, a first phase compensation network, a first impedance transformation network, a second phase compensation network, and a second impedance transformation network;
  • the output end of the first power amplifier is connected with the input end of the first matching network
  • the output end of the second power amplifier is connected with the input end of the second matching network
  • the output end of the first matching network is connected with the first input end of the coupler
  • the output end of the second matching network is connected with the second input end of the coupler
  • the printed circuit board further includes:
  • PA1 is configured as the Main path
  • PA2 is configured as the Peak path.
  • the phase relationship between the first phase compensation network and the first matching network (the second matching network) is as follows: shown in formula 2;
  • PA1 When the working frequency band belongs to the fourth preset frequency band, PA1 is configured as the Peak path, PA2 is configured as the Main path, and the phase relationship between the first phase compensation network and the first matching network (the second matching network) is as shown in Equation 3 Show.
  • PA1 is configured as the Main path
  • PA2 is configured as the Peak path.
  • the phase relationship between the second phase compensation network and the first matching network (the second matching network) is as follows: shown in formula 2;
  • PA1 When the working frequency band belongs to the third preset frequency band, PA1 is configured as the Peak path, PA2 is configured as the Main path, and the phase relationship between the second phase compensation network and the first matching network (second matching network) is as shown in Equation 3 Show.
  • the working principle of the Doherty power amplifier in this embodiment is the same as that in Embodiment 1, and details are not repeated in this embodiment.
  • phase compensation network and the impedance transformation network, and the configuration of the main power amplifier and the auxiliary power amplifier, the phase relationship between the phase compensation network and the first matching network (second matching network) in the embodiment of the present application can be satisfied. , so as to realize the pulling characteristics of the Doherty power amplifier in multiple frequency bands.
  • the second output end of the coupling is connected to the first phase compensation network.
  • the additional phase introduced by the DC blocking capacitor C1 welded between the first phase compensation network and the second output terminal of the coupler at each operating frequency point is considered in ⁇ 2; correspondingly, when the second output terminal of the coupler is used as the circuit When the power is output, the first output end of the coupling is connected to the second phase compensation network.
  • the second phase network it is necessary to weld the spacer between the second phase compensation network and the first output end of the coupler.
  • the extra phase introduced by the direct capacitor C4 at each operating frequency is considered in ⁇ 2.
  • the embodiment of the present application provides another printed circuit board, which includes the following structure:
  • a first power amplifier a second power amplifier, a first matching network, a second matching network, a coupler, a first phase compensation network, a second phase compensation network, a first impedance transformation network, and a second impedance transformation network;
  • the output end of the first power amplifier is connected with the input end of the first matching network
  • the output end of the second power amplifier is connected with the input end of the second matching network
  • the output end of the first matching network is connected with the first input end of the coupler connection
  • the output end of the second matching network is connected with the second input end of the coupler
  • the second output end of the coupler is connected with the first phase compensation network
  • the first output end of the coupler is connected with the second phase compensation network
  • the printed circuit board further includes:
  • a DC blocking capacitor C1 is connected to the reserved first welding point.
  • the second output port of the coupler is used as power output, and the first impedance transformation network is used to realize impedance transformation from characteristic impedance to load impedance.
  • PA1 is configured as the Main path
  • PA2 is configured as the Peak path.
  • the phase relationship between the first phase compensation network and the first matching network (the second matching network) is as follows: shown in formula 2;
  • PA1 When the working frequency band belongs to the fourth preset frequency band, PA1 is configured as the Peak path, PA2 is configured as the Main path, and the phase relationship between the first phase compensation network and the first matching network (the second matching network) is as shown in Equation 3 Show.
  • the second phase compensation network in order to realize the connection and conduction between the second phase compensation network and the second impedance transformation network, it is necessary to connect the DC blocking capacitor C2 at the position of the reserved second welding point.
  • the first output port of the coupler is used as power output
  • the second impedance transformation network is used to realize impedance transformation from characteristic impedance to load impedance.
  • PA1 is configured as the Main path
  • PA2 is configured as the Peak path.
  • the phase relationship between the second phase compensation network and the first matching network (the second matching network) is as follows: shown in formula 2;
  • PA1 When the working frequency band belongs to the third preset frequency band, PA1 is configured as the Peak path, PA2 is configured as the Main path, and the phase relationship between the second phase compensation network and the first matching network (second matching network) is as shown in Equation 3 Show.
  • the working principle of the Doherty power amplifier in this embodiment is the same as that in Embodiment 1, and details are not repeated in this embodiment.
  • the second output terminal of the coupler when used as a power output, the second output terminal of the coupler is connected to the first phase compensation network, the DC blocking capacitor C1, and the first impedance transformation network in sequence to realize each work.
  • the transformation from the characteristic impedance of the frequency point to the load impedance correspondingly, when the first output end of the coupler is used as the power output of the circuit, the first output end of the coupler is connected to the second phase compensation network, the DC blocking capacitor C2, the The two impedance transformation networks are connected in sequence to realize the transformation from the characteristic impedance of each operating frequency point to the load impedance.
  • the printed circuit board provided by the embodiment of the present application reflects all possible circuit structures. When using it, the phase compensation network and the impedance transformation network are switched by reasonably selecting the output port, and the Main circuit and the Peak circuit are combined. The different configurations of the circuit make one printed circuit board compatible with multiple operating frequency bands, and at the same time realize the reconfigurability of the Doherty power amplifier without introducing additional insertion loss, which makes the circuit’s RF performance better.
  • the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.
  • computer-usable storage media including, but not limited to, disk storage, CD-ROM, optical storage, etc.
  • These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions
  • the apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

Abstract

本申请公开了一种Doherty功率放大器、印刷电路板及基站，包括：功放单元，包括第一功放和第二功放，用于分别接收输入信号，并进行功率放大，第一功放被配置为主功放或辅功放，第二功放被配置为与第一功放不同的功放类型，辅功放基于输入信号不同功率下的工作状态，和主功放进行有源负载牵引；合路单元，包括第一匹配网络、第二匹配网络、耦合器和相位补偿网络，用于在回退点和满功率点时进行阻抗匹配，第一匹配网络与相位补偿网络满足设定的相位关系；耦合器，用于将主功放输出的放大信号与辅功放输出的放大信号进行功率合成；相位补偿网络，用于基于Doherty功率放大器的工作频段形成相位关系；阻抗变换网络，连接后级负载。

Description

一种Doherty功率放大器、印刷电路板及基站 技术领域
本申请涉及通信技术领域，尤其涉及一种Doherty功率放大器、印刷电路板及基站。
背景技术
带宽扩容是无线通信演进的鲜明特征，其中包括更多的频谱分频、更宽的信号带宽，以支持更大的数据传输率和数据容量。现在的无线通信系统能够兼容多个无线通信标准，并且各无线通信标准又涉及多个工作频段，因此，导致无线通信系统使用的频段比较零碎，频带越来越宽。为了满足全球各运营商的需求，这也就要求所开发的无线通信系统需要具备宽带和多带的特性，支撑多模多带，无线通信系统中的网络设备内的射频模块需要具有混合低中高频段的射频能力。
因此，作为射频模块的射频功率放大器，宽频、多频技术同样成为热门方向和趋势所在。在网络设备中，射频模块里面可以包含700/800/900MHz、1800MHz、2100MHz、2600MHz到3.5/4.9/5.8GHz等多个功放。
Doherty功率放大器基于有源负载调制原理，能够有效的提高回退效率，从而提高功放效率，已广泛运用在网络设备中。如图1所示为Doherty功率放大器的工作原理图，如图2所示为Doherty功率放大器的效率曲线图。其中，宽频、多频Doherty功率放大器的设计核心在于输入输出网络需具备的宽带、多频特性。
如图3所示为现有技术中的一种双频Doherty功率放大器结构，其将传统Doherty功率放大器中的功分网络、相位补偿网络、阻抗逆变网络、阻抗变换网络，分别用相应的双频功分网络、双频相位补偿网络、双频阻抗逆变网络、双频阻抗变换网络进行各部分的替代，以实现双频Doherty的设计。但其只能工作在两个频段，其当功放需要工作在更多频段时，则需要利用多频带功分网络，相位补偿网络，阻抗逆变网络，阻抗变换网路进行各部分的替代，并且其功放不具备可重构特性。
如图4所示为现有技术中的一种基于耦合器的Doherty功率放大器结构，其主要用于调节耦合器第二输出端口的短路线或者开路线以实现Doherty功率放大器的牵引特性。但其工作带宽有限，很难同时兼顾如低频700MHz、800MHz、900MHz和高频3.5GHz、5.8GHz多个频段，且不具备可重构特性。
综上，现有技术中的Doherty功率放大器虽然可以实现多频段下的牵引特性，但是结构复杂，且不具备可重构特性。
发明内容
本申请提供一种Doherty功率放大器、印刷电路板及基站，用以在多个频段下实现Doherty功率放大器的牵引特性，且结构简单，具备可重构特性。
第一方面，本申请实施例提供一种Doherty功率放大器，包括：
功放单元，包括第一功放和第二功放，用于分别接收输入信号，并对所述输入信号进行功率放大处理，其中，所述第一功放被配置为主功放或辅功放，所述第二功放被配置为主功放和辅功放中与所述第一功放不同的功放类型，所述辅功放基于不同功率输入信号下 的工作状态，和所述主功放进行有源负载牵引；
合路单元，包括第一匹配网络、第二匹配网络、耦合器和相位补偿网络，用于在所述Doherty功率放大器位于回退点和满功率点时进行阻抗匹配，其中，所述第一匹配网络或所述第二匹配网络与所述相位补偿网络满足预设相位关系；
所述第一匹配网络用于接收所述主功放发送的放大信号并输入至耦合器，所述第二匹配网络用于接收所述辅功放发送的放大信号并输入至耦合器；
所述耦合器，用于将所述主功放输出的放大信号与所述辅功放输出的放大信号进行功率合成，并发送至所述阻抗变换网络；
所述相位补偿网络，用于基于所述Doherty功率放大器的工作频段，形成所述预设相位关系，其中，所述工作频段为至少一个频段；
所述阻抗变换网络，连接后级负载，用于将所述Doherty功率放大器的特征阻抗变换至与所述后级负载相匹配的阻抗。
本发明实施例提供的Doherty功率放大器，包括主功放、辅功放、第一匹配网络、第二匹配网络、耦合器、相位补偿网络和阻抗变换网络，其中主功放和辅功放用于将输入信号进行功率放大，辅功放基于不同功率输入信号下的工作状态，和所述主功放进行有源负载牵引；耦合器结合满足一定相位关系的匹配单元与相位补偿网络，完成双功率阻抗匹配，即将Doherty功率放大器位于回退点时的阻抗以及Doherty功率放大器满功率时的阻抗均匹配至特征阻抗，同时，通过耦合器将主功放和辅功放的放大信号进行功率合成，输出至阻抗变换网络，最后由阻抗变换网络将特征阻抗变换至负载阻抗。与现有技术相比，在输入信号的不同频段下，通过合理设计相位补偿网络以满足本实施例中的相位关系，并配置相应的Main路和Peak路，实现多个频段下Doherty功率放大器的牵引效果，同时结构简单，具备可重构特性。
在一种可能的实施方式中，所述耦合器的特征阻抗为Z0，其满足以下公式：
Figure PCTCN2020112739-appb-000001
其中，R opt为所述主功放偏置在B类下的阻抗，V dd为所述主功放的漏极工作电压，V knee为所述主功放的膝值电压，P sat为所述主功放的饱和输出功率。
本发明实施例提供的Doherty功率放大器，其中耦合器的特征阻抗基于上述公式，根据主功放(辅功放)偏置在B类下的阻抗，即最优阻抗R opt进行优化，确定特征阻抗Z0，以实现Doherty功率放大器最优的射频性能。
在一种可能的实施方式中，所述耦合器第二输出端连接所述相位补偿网络，所述耦合器第一输出端连接所述阻抗变换网络；
当所述工作频段为第一预设频段时，所述第一功放被配置为主功放，所述第二功放被配置为辅功放；
当所述工作频段为第二预设频段时，所述第一功放被配置为辅功放，所述第二功放被配置为主功放。
在一种可能的实施方式中，所述耦合器第一输出端连接所述相位补偿网络，所述耦合器第二输出端连接所述阻抗变换网络；
当所述工作频段为第三预设频段时，所述第一功放被配置为主功放，所述第二功放被配置为辅功放；
当所述工作频段为第四预设频段时，所述第一功放被配置为辅功放，所述第二功放被配置为主功放。
在一种可能的实施方式中，所述第一预设频段、所述第二预设频段、所述第三预设频段和所述第四预设频段均为不同频段。
本发明实施例提供的Doherty功率放大器，通过合理选择输出端口，对相位补偿网络和阻抗变换网络进行切换，结合对第一功放和第二功放的不同配置，使得Doherty功率放大器能够设计多种方案，实现Doherty功率放大器的多频可重构性。
在一种可能的实施方式中，当所述工作频段为第一预设频段和/或第四预设频段时：
所述第一匹配网络和所述第二匹配网络为相同网络，所述网络等效为特征阻抗为Z0，相位为θ1的微带网络；
所述相位补偿网络等效为特征阻抗为Z0，相位为θ2的微带网络，其中θ2为所述第一预设频段和/或第四预设频段所对应的相位角，所述θ1与θ2满足以下公式：
Figure PCTCN2020112739-appb-000002
在一种可能的实施方式中，当所述设置工作频段为所述第二预设频段和/或第三预设频段时：
所述第一匹配网络和所述第二匹配网络为相同网络，所述网络等效为特征阻抗为Z0，相位为θ1的微带网络；
所述相位补偿网络等效为特征阻抗为Z0，相位为θ2的微带网络，其中θ2为所述第二预设频段和/或第三预设频段所对应的相位角，所述θ1与θ2满足以下公式：
Figure PCTCN2020112739-appb-000003
本发明实施例提供的Doherty功率放大器，在不同工作频段下，只需要设计相位补偿网络以满足上述的两个相位关系中的其中一个，并配置对应的主功放和辅功放的位置，即可实现多个频段下Doherty功率放大器的牵引效果。
在一种可能的实施方式中，所述主功放为AB类或B类功放，所述辅功放为C类功放。
第二方面，本申请实施例提供一种印刷电路板，包含本申请实施例第一方面所述的Doherty功率放大器。
第三方面，本申请实施例提供一种印刷电路板，包含有以下结构：
第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第二相位补偿网络、第一阻抗变换网络和第二阻抗变换网络；
其中，所述第一功放的输出端与所述第一匹配网络的输入端连接，所述第二功放的输出端与所述第二匹配网络的输入端连接，所述第一匹配网络的输出端与耦合器第一输入端连接，所述第二匹配网络的输出端与耦合器第二输入端连接；
所述电路板还包括：
连接所述耦合器第二输出端与所述第一相位补偿网络的第一焊接点；
连接所述耦合器第二输出端与所述第二阻抗变换网络的第二焊接点；
连接所述耦合器第一输出端与所述第一阻抗变换网络的第三焊接点；
连接所述耦合器第一输出端与所述第二相位补偿网络的第四焊接点。
本申请实施例提供的印刷电路板，将所有可能实现的电路结构均体现出来，具体使用时，通过合理选择输出端口，以及通过在第一、四焊接点或第二、三焊接点配置隔直电容， 对相位补偿网络和阻抗变换网络进行切换，结合对主功放和辅功放的不同配置，使得一个印刷电路板上能够兼容多个工作频段，实现Doherty功率放大器的多频可重构性，同时不会引入额外的插损，使得电路的射频性能更优。
第四方面，本申请实施例提供另一印刷电路板，包含有以下结构：
第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第二相位补偿网络、第一阻抗变换网络和第二阻抗变换网络；
其中，所述第一功放的输出端与所述第一匹配网络的输入端连接，所述第二功放的输出端与所述第二匹配网络的输入端连接，所述第一匹配网络的输出端与耦合器第一输入端连接，所述第二匹配网络的输出端与耦合器第二输入端连接，所述耦合器第二输出端与所述第一相位补偿网络连接，所述耦合器第一输出端与所述第二相位补偿网络连接；
所述电路板还包括：
连接所述第一阻抗变换网络与所述第一相位补偿器的第五焊接点；
连接所述第二阻抗变换网络与所述第二相位补偿器的第六焊接点。
本申请实施例提供的印刷电路板，将所有可能实现的电路结构均体现出来，具体使用时，通过合理选择输出端口，以及通过在第五焊接点或第六焊接点配置隔直电容，对相位补偿网络和阻抗变换网络进行切换，结合对主功放和辅功放的不同配置，使得一个印刷电路板上能够兼容多个工作频段，实现Doherty功率放大器的多频可重构性，同时不会引入额外的插损，使得电路的射频性能更优。
第五方面，本申请实施例提供一种基站，包括本申请实施例第一方面所述的Doherty功率放大器。
附图说明
图1为现有技术中提供的一种Doherty功率放大器的结构示意图；
图2为现有技术中提供的一种Doherty功率放大器的工作效率曲线图；
图3为现有技术中提供的一种双频Doherty功率放大器的结构示意图；
图4为现有技术中提供的一种基于耦合器的Doherty功率放大器的结构示意图；
图5为本申请实施例提供的一种小站射频模块的结构示意图；
图6为本申请实施例提供的一种Doherty功率放大器的结构示意图；
图7为本申请实施例提供的另一Doherty功率放大器的结构示意图；
图8为本申请实施例提供的又一Doherty功率放大器的结构示意图；
图9为本申请实施例提供的再一Doherty功率放大器的结构示意图；
图10为本申请实施例提供的再一Doherty功率放大器的结构示意图；
图11为本申请实施例提供的一种Doherty功率放大器的等效电路图；
图12为本申请实施例提供的另一Doherty功率放大器的等效电路图；
图13(a)为本申请实施例提供的一种Doherty功率放大器的工作效率随输入电压变化曲线图；
图13(b)为本申请实施例提供的一种Doherty功率放大器的Main路和Peak路电流源平面电流随输入电压变化曲线图；
图13(c)为本申请实施例提供的一种Doherty功率放大器的Main路和Peak路电流源平面电压随输入电压变化曲线图；
图13(d)为本申请实施例提供的一种Doherty功率放大器的Main路和Peak路电流源平面阻抗随输入电压变化曲线图；
图14为本申请实施例提供的一种印刷电路板的结构示意图；
图15为本申请实施例提供的另一印刷电路板的结构示意图；
图16为本申请实施例提供的又一印刷电路板的结构示意图；
图17为本申请实施例提供的再一印刷电路板的结构示意图；
图18为本申请实施例提供的再一印刷电路板的结构示意图；
图19为本申请实施例提供的再一印刷电路板的结构示意图。
具体实施方式
功率放大器是发射机中一种将直流信号转换为交流信号，并对输入信号进行功率放大的功能模块。而Doherty功率放大器，是一种基于有源负载调制技术的功率放大器，相比于传统的功率放大器，Doherty功率放大器在功放回退工作时，可以达到更高的效率。
图1中示例性的示出了Doherty功率放大器的结构示意图，其包括主功率放大器、辅功率放大器和阻抗变换网络，结合图2中Doherty功率放大器的效率曲线图可知，在输入功率较小时，只有主功放工作，并逐渐达到饱和状态；随着输入功率的逐渐增大，辅功放打开，实现Doherty功率放大器的有源负载牵引，直到主功放与辅功放均达到饱和状态。
Doherty功率放大器的结构简单，且能够有效的提高回退效率，从而提升功放效率，但其工作带宽有限，很难同时兼顾如低频700MHz、800MHz、900MHz，高频3.5GHz、5.8GHz等多个频段，并且电路结构不具备可重构特性。基于此，如图5所示，为室内小站的射频模块示意图，其中包含了多个频段的发射通道，进一步地，本申请实施例提供一种Doherty功率放大器，使得其同时具备多频特性，且具备可重构特性，能够工作在多个频段下，满足多个频点的任意单频可配置，同时也可以实现部分频点的多频并发等场景。
下面结合附图，对本申请实施例进行详细描述。
实施例一
如图6所示，本申请实施例提供一种Doherty功率放大器，包括：
功放单元，包括第一功放(PA1)和第二功放(PA2)，用于分别接收输入信号，并对输入信号进行功率放大处理得到放大信号，其中，第一功放被配置为主功放或辅功放，第二功放被配置为主功放和辅功放中与第一功放不同的功放类型，辅功放基于在不同功率输入信号下的工作状态，和主功放进行有源负载牵引；
合路单元，包括第一匹配网络、第二匹配网络、耦合器和相位补偿网络，用于在Doherty功率放大器位于回退点和满功率点时进行阻抗匹配，其中，第一匹配网络或第二匹配网络与相位补偿网络满足设定的相位关系；
第一匹配网络用于接收主功放发送的放大信号并输入至耦合器，第二匹配网络用于接收辅功放发送的放大信号并输入至耦合器；
耦合器，用于将主功放的放大信号与辅功放的放大信号进行功率合成；
相位补偿网络，用于基于Doherty功率放大器的工作频段，形成与匹配单元中任一匹配网络之间的相位关系，其中，工作频段为至少一个频段；
阻抗变换网络，连接后级负载，用于将Doherty功率放大器的特征阻抗变换至与后级负载相匹配的阻抗。
如图7所示，Doherty功率放大器中耦合器第二输出端连接相位补偿网络，耦合器第一输出端连接阻抗变换网络，当工作频段为第一预设频段f1时，PA1被配置为主功放，PA2被配置为辅功放。
如图8所示，Doherty功率放大器中耦合器第二输出端连接相位补偿网络，耦合器第一输出端连接阻抗变换网络，当工作频段为第二预设频段f2时，PA1被配置为辅功放，PA1被配置为主功放。
如图9所示，Doherty功率放大器中耦合器第一输出端连接相位补偿网络，耦合器第二输出端连接阻抗变换网络，当工作频段为第三预设频段f3时，PA1被配置为主功放，PA2被配置为辅功放。
如图10所示，Doherty功率放大器中耦合器第一输出端连接相位补偿网络，耦合器第二输出端连接阻抗变换网络，当工作频段为第四预设频段f4时，PA1被配置为辅功放，PA1被配置为主功放。
需要说明的是，在图7-10中，主功放和辅功放为相同配置的功放元件，第一匹配网络和第二匹配网络为相同网络，等效为特征阻抗为Z0、相位为θ1的微带网络，相位补偿网络等效为特征阻抗为Z0、相位为θ2的微带网络，耦合器的特征阻抗为Z0。其中，耦合器的特征阻抗Z0根据主功放(辅功放)的最优阻抗R opt进行优化，以实现最优的射频性能，其中，Z0与R opt之间的关系可以通过公式1来表示：
Figure PCTCN2020112739-appb-000004
其中，V dd为主功放(辅功放)的漏极工作电压，V knee为主功放(辅功放)的膝值电压，P sat为主功放(辅功放)的饱和输出功率。
如图11所示，相位补偿网络等效为特征阻抗为Z0、相位为θ2的开路线，当工作频段为f1和/或f4时，第一匹配网络(第二匹配网络)的相位θ1与相位补偿网络的相位θ2之间的关系满足公式2：
Figure PCTCN2020112739-appb-000005
如图12所示，相位补偿网络等效为特征阻抗为Z0、相位为θ2的开路线，当工作频段为f2和/或f3时，第一匹配网络(第二匹配网络)的相位θ1与相位补偿网络的相位θ2之间的关系满足公式3：
Figure PCTCN2020112739-appb-000006
进一步地，Doherty功率放大器在工作时分为两路，一路为Main(主功放)路，偏置状态为AB/B类，一路为Peak(辅功放)路，偏置状态为C类，Doherty功率放大器仿真结果如图13所示，其中，图13(a)为Doherty功率放大器的工作效率随输入电压变化曲线图，图13(b)为Doherty功率放大器的Main路和Peak路电流源平面电流随输入电压变化曲线图，图13(c)为Doherty功率放大器的Main路和Peak路电流源平面电压随输入电压变化曲线图，图13(d)为Doherty功率放大器的Main路和Peak路电流源平面阻抗随输入电压变化曲线图。
由图13可知，在输入信号功率较小时，Peak路处于关断状态，电流为0，此时Peak路的阻抗是无穷大的。而当输入信号的功率慢慢增大，Peak路打开，和Main路进行有源负载牵引，Main路阻抗从50Ohm慢慢变小至25Ohm，同时，Peak路阻抗由开路牵引至 25Ohm，直至两路功放均饱和。
需要说明的是，其中Main路阻抗的变化范围不限定于50Ohm至25Ohm，也可以是其他变化范围，例如50Ohm至10Ohm、或75Ohm至25Ohm；同时Peak路阻抗的变化范围也不限定于由无穷大减小至25Ohm，也可以由无穷大减小至其他值，本申请对此均不做限定。
进一步地，随着输入信号功率强度的不同，可以将Doherty功率放大器的工作区域大致分为三个阶段：低功率区域、回退区域、满功率区域。下面结合图9，对以上三个阶段进行具体描述：
1)低功率区域
在低功率区域，由于Peak路的偏置状态为C类，输入功率不足以驱动使其工作，此时Peak路处于开路状态。同时，Main路阻抗保持不变、随着输出功率增大，Main路进入饱和状态，电压达到满摆幅，实现Doherty功率放大器工作过程中的第一个高功率点。
2)回退区域
随着输入功率的逐渐增强，Peak路打开，和Main路进行有源负载牵引，此时Main路阻抗逐渐变小，但其电压一直为满摆幅，保持饱和状态；同时，Peak路阻抗也逐渐变小，电压逐渐升高，但并未达到饱和状态，因此Doherty功率放大器的工作效率略微下降。
3)满功率区域
输入功率进一步增强，Main路和Peak路均达到饱和状态，电压均达到满摆幅，此时Doherty功率放大器实现工作过程中的第二个高功率点。
进一步地，耦合器结合满足一定相位关系的匹配单元与相位补偿网络，完成双功率阻抗匹配，即将Doherty功率放大器位于回退点时的阻抗以及Doherty功率放大器满功率时的阻抗均匹配至特征阻抗，同时，通过耦合器将主功放和辅功放的放大信号进行功率合成，输出至阻抗变换网络，最后由阻抗变换网络将特征阻抗变换至负载阻抗。
因此，在不同工作频段下，只需要通过设计相位补偿网络以满足本实施例中的相位关系，并配置相应的Main路和Peak路，即可实现多个频段下Doherty功率放大器的牵引效果。
在一种可能的实施方式中，可以通过以下方式来设计本申请实施例提供的多频段Doherty功率放大器：
根据主功放(辅功放)的最优阻抗，确定第一匹配网络、第二匹配网络、耦合器和相位补偿网络的特征阻抗Z0；
设计第一匹配网络(第二匹配网络)，确定不同工作频点下第一匹配网络(第二匹配网络)的相位θ1；
设计特征阻抗为Z0的耦合器；
根据工作频段，结合上述相位关系确定相位补偿网络的相位θ2的可能值，进行相位补偿网络的设计；
根据第一匹配网络(第二匹配网络)的相位θ1与相位补偿网络的相位θ2之间的关系，结合相位补偿网络、阻抗变换网络与耦合器的连接方式，配置功放元件的属性，确定主功放和辅功放的位置。
通过设计相位补偿网络，使得电路在输入信号不同频率下满足两个相位关系中的任一个，同时根据相位关系所需对应的功放元件配置，即可实现多个频段下Doherty功率放大 器的牵引效果。
实施例二
本申请实施例提供一种印刷电路板，使得在不同功放配置下，耦合器的第一输出端和第二输出端可进行网络切换，以在不同的工作频段选择不同的输出端口作为功率输出。需要说明的是，该印刷电路板在进行输出端口的网络切换时，是以通过隔直电容的焊接来实现的，进而只通过BOM(Bill of Material，物料清单)的修改实现Doherty功率放大器的可重构性。
进一步地，如图14所示，本申请实施例提供的印刷电路板包括以下结构：
第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第一阻抗变换网络、第二相位补偿网络和第二阻抗变换网络；
其中，第一功放的输出端与第一匹配网络的输入端连接，第二功放的输出端与第二匹配网络的输入端连接，第一匹配网络的输出端与耦合器第一输入端连接，第二匹配网络的输出端与耦合器第二输入端连接；
在一种可能的实施方式中，所述印刷电路板还包括：
连接耦合器第二输出端与第一相位补偿网络的第一焊接点A1；
连接耦合器第二输出端与第二阻抗变换网络的第二焊接点A2；
连接耦合器第一输出端与第一阻抗变换网络的第三焊接点A3；
连接耦合器第一输出端与第二相位补偿网络的第四焊接点A4。
如图15所示，为了使第一相位补偿网络满足Doherty功率放大器工作中所需的相位关系，需要在预留的第一焊接点的位置上焊接隔直电容C1，同时，为了实现耦合器第一输出端与第一阻抗变换网络的连接与导通，需要在预留的第三焊接点的位置上接入隔直电容C3。此时，耦合器的第一输出端作为功率输出，第一阻抗变换网络用于实现特征阻抗到负载阻抗的变换。
此时，当工作频段属于第一预设频段时，PA1被配置为Main路，PA2被配置为Peak路，第一相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式2所示；
当工作频段属于第四预设频段时，PA1被配置为Peak路，PA2被配置为Main路，第一相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式3所示。
如图16所示，为了实现耦合器第二输出端与第二阻抗变换网络的连接与导通，需要在预留的第二焊接点的位置上接入隔直电容C2，同时，为了使第二相位补偿网络满足电路工作过程中所需的相位关系，需要在预留的第四焊接点的位置上接入隔直电容C4。此时，耦合器的第二输出端作为功率输出，第二阻抗变换网络用于实现特征阻抗到负载阻抗的变换。
此时，当工作频段属于第二预设频段时，PA1被配置为Main路，PA2被配置为Peak路，第二相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式2所示；
当工作频段属于第三预设频段时，PA1被配置为Peak路，PA2被配置为Main路，第二相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式3所示。
进一步地，在本实施例中Doherty功率放大器的工作原理与实施例一中相同，本实施例中不再赘述。
通过以上对相位补偿网络和阻抗变换网络的连接，及对主功放和辅功放的配置，即可满足本申请实施例中相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系，从 而实现多个频段下的Doherty功率放大器的牵引特性。
需要说明的是，当耦合器的第一输出端作为Doherty功率放大器的功率输出时，耦合的第二输出端连接第一相位补偿网络，此时在对第一相位补偿网络进行设计时，需要将焊接在第一相位补偿网络与耦合器第二输出端之间的隔直电容C1在各工作频点所引入的额外相位考虑在θ2中；对应地，当耦合器的第二输出端作为电路的功率输出时，耦合的第一输出端连接第二相位补偿网络，此时在对第二相位网络进行设计时，需要将焊接在第二相位补偿网络与耦合器的第一输出端之间的隔直电容C4在各工作频点所引入的额外相位考虑在θ2中。
实施例三
如图17所示，本申请实施例提供另一种印刷电路板，其包括以下结构：
第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第二相位补偿网络、第一阻抗变换网络和第二阻抗变换网络；
其中，第一功放的输出端与所述第一匹配网络的输入端连接，第二功放的输出端与第二匹配网络的输入端连接，第一匹配网络的输出端与耦合器第一输入端连接，第二匹配网络的输出端与耦合器第二输入端连接，耦合器第二输出端与第一相位补偿网络连接，耦合器第一输出端与第二相位补偿网络连接；
在一种可能的实施方式中，印刷电路板还包括：
连接第一阻抗变换网络与第一相位补偿器的第五焊接点A5；
连接第二阻抗变换网络与第二相位补偿器的第六焊接点A6。
如图18所示，为了实现第一相位补偿网络与第一阻抗变换网络的连接于导通，在预留的第一焊接点的位置上接入隔直电容C1。此时，耦合器的第二输出端口作为功率输出，第一阻抗变换网络用于实现特征阻抗到负载阻抗的阻抗变换。
此时，当工作频段属于第一预设频段时，PA1被配置为Main路，PA2被配置为Peak路，第一相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式2所示；
当工作频段属于第四预设频段时，PA1被配置为Peak路，PA2被配置为Main路，第一相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式3所示。
或者，
如图19所示，为了实现第二相位补偿网络与第二阻抗变换网络的连接与导通，需要在预留的第二焊接点的位置上接入隔直电容C2。此时，耦合器的第一输出端口作为功率输出，第二阻抗变换网络用于实现特征阻抗到负载阻抗的阻抗变换。
此时，当工作频段属于第二预设频段时，PA1被配置为Main路，PA2被配置为Peak路，第二相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式2所示；
当工作频段属于第三预设频段时，PA1被配置为Peak路，PA2被配置为Main路，第二相位补偿网络与第一匹配网络(第二匹配网络)之间的相位关系如公式3所示。
进一步地，在本实施例中Doherty功率放大器的工作原理与实施例一中相同，本实施例中不再赘述。
需要说明的是，当耦合器的第二输出端作为功率输出时，此时耦合器的第二输出端与第一相位补偿网络、隔直电容C1、第一阻抗变换网络依次连接，实现各工作频点特征阻抗到负载阻抗的变换；对应地，当耦合器的第一输出端作为电路的功率输出时，此时耦合器的第一输出端与第二相位补偿网络、隔直电容C2、第二阻抗变换网络依次连接，实现各工 作频点特征阻抗到负载阻抗的变换。
进一步地，本申请实施例提供的印刷电路板，将所有可能实现的电路结构均体现出来，具体使用时，通过合理选择输出端口，对相位补偿网络和阻抗变换网络进行切换，结合Main路和Peak路的不同配置，使得一个印刷电路板上能够兼容多个工作频段，同时实现Doherty功率放大器的可重构性，同时不会引入额外的插损，使得电路的射频性能更优。
本领域内的技术人员应明白，本申请的实施例可提供为方法、系统、或计算机程序产品。因此，本申请可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。而且，本申请可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器、CD-ROM、光学存储器等)上实施的计算机程序产品的形式。
本申请是参照根据本申请的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器，使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中，使得存储在该计算机可读存储器中的指令产生包括指令装置的制造品，该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上，使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理，从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。
显然，本领域的技术人员可以对本申请进行各种改动和变型而不脱离本申请的保护范围。这样，倘若本申请的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (12)

  1. 一种Doherty功率放大器，其特征在于，包括：
    功放单元，包括第一功放和第二功放，用于分别接收输入信号，并对所述输入信号进行功率放大处理得到放大信号，其中，所述第一功放被配置为主功放或辅功放，所述第二功放被配置为主功放和辅功放中与所述第一功放不同的功放类型，所述辅功放基于不同功率输入信号下的工作状态，和所述主功放进行有源负载牵引；
    合路单元，包括第一匹配网络、第二匹配网络、耦合器和相位补偿网络，用于在所述Doherty功率放大器位于回退点和满功率点时进行阻抗匹配，其中，所述第一匹配网络或所述第二匹配网络与所述相位补偿网络满足设定的相位关系；
    所述第一匹配网络用于接收所述主功放发送的放大信号并输入至耦合器，所述第二匹配网络用于接收所述辅功放发送的放大信号并输入至耦合器；
    所述耦合器，用于将所述主功放输出的放大信号与所述辅功放输出的放大信号进行功率合成，并发送至所述阻抗变换网络；
    所述相位补偿网络，用于基于所述Doherty功率放大器的工作频段，形成所述相位关系，其中，所述工作频段为至少一个频段；
    所述阻抗变换网络，连接后级负载，用于将所述Doherty功率放大器的特征阻抗变换至与所述后级负载相匹配的阻抗。
  2. 根据权利要求1所述的功率放大器，其特征在于，
    所述耦合器的特征阻抗为Z0，其满足以下公式：
    Figure PCTCN2020112739-appb-100001
    其中，R opt为所述主功放偏置在B类下的阻抗，V dd为所述主功放的漏极工作电压，V knee为所述主功放的膝值电压，P sat为所述主功放的饱和输出功率。
  3. 根据权利要求1所述的功率放大器，其特征在于，所述耦合器第二输出端连接所述相位补偿网络，所述耦合器第一输出端连接所述阻抗变换网络；
    当所述工作频段为第一预设频段时，所述第一功放被配置为主功放，所述第二功放被配置为辅功放；
    当所述工作频段为第二预设频段时，所述第一功放被配置为辅功放，所述第二功放被配置为主功放。
  4. 根据权利要求1所述的功率放大器，其特征在于，所述耦合器第一输出端连接所述相位补偿网络，所述耦合器第二输出端连接所述阻抗变换网络；
    当所述工作频段为第三预设频段时，所述第一功放被配置为主功放，所述第二功放被配置为辅功放；
    当所述工作频段为第四预设频段时，所述第一功放被配置为辅功放，所述第二功放被配置为主功放。
  5. 根据权利要求3或4所述的功率放大器，其特征在于，
    所述第一预设频段、所述第二预设频段、所述第三预设频段和所述第四预设频段均为不同频段。
  6. 根据权利要求5所述的功率放大器，其特征在于，当所述工作频段为第一预设频 段和/或第四预设频段时：
    所述第一匹配网络和所述第二匹配网络为相同网络，所述网络等效为特征阻抗为Z0，相位为θ1的微带网络；
    所述相位补偿网络等效为特征阻抗为Z0，相位为θ2的微带网络，其中θ2为所述第一预设频段和/或第四预设频段所对应的相位角，所述θ1与θ2满足以下公式：
    Figure PCTCN2020112739-appb-100002
  7. 根据权利要求5所述的功率放大器，其特征在于，当所述设置工作频段为所述第二预设频段和/或第三预设频段时：
    所述第一匹配网络和所述第二匹配网络为相同网络，所述网络等效为特征阻抗为Z0，相位为θ1的微带网络；
    所述相位补偿网络等效为特征阻抗为Z0，相位为θ2的微带网络，其中θ2为所述第二预设频段和/或第三预设频段所对应的相位角，所述θ1与θ2满足以下公式：
    Figure PCTCN2020112739-appb-100003
  8. 根据权利要求1所述的功率放大器，其特征在于，所述主功放为AB类或B类功放，所述辅功放为C类功放。
  9. 一种印刷电路板，其特征在于，包含有如权利要求1-8任一所述的Doherty功率放大器。
  10. 一种印刷电路板，其特征在于，包含有以下结构：
    第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第二相位补偿网络、第一阻抗变换网络和第二阻抗变换网络；
    其中，所述第一功放的输出端与所述第一匹配网络的输入端连接，所述第二功放的输出端与所述第二匹配网络的输入端连接，所述第一匹配网络的输出端与耦合器第一输入端连接，所述第二匹配网络的输出端与耦合器第二输入端连接；
    所述电路板还包括：
    连接所述耦合器第二输出端与所述第一相位补偿网络的第一焊接点；
    连接所述耦合器第二输出端与所述第二阻抗变换网络的第二焊接点；
    连接所述耦合器第一输出端与所述第一阻抗变换网络的第三焊接点；
    连接所述耦合器第一输出端与所述第二相位补偿网络的第四焊接点。
  11. 一种印刷电路板，其特征在于，包含有以下结构：
    第一功放、第二功放、第一匹配网络、第二匹配网络、耦合器、第一相位补偿网络、第二相位补偿网络、第一阻抗变换网络和第二阻抗变换网络；
    其中，所述第一功放的输出端与所述第一匹配网络的输入端连接，所述第二功放的输出端与所述第二匹配网络的输入端连接，所述第一匹配网络的输出端与耦合器第一输入端连接，所述第二匹配网络的输出端与耦合器第二输入端连接，所述耦合器第二输出端与所述第一相位补偿网络连接，所述耦合器第一输出端与所述第二相位补偿网络连接；
    所述电路板还包括：
    连接所述第一阻抗变换网络与所述第一相位补偿器的第五焊接点；
    连接所述第二阻抗变换网络与所述第二相位补偿器的第六焊接点。
  12. 一种基站，其特征在于，包括权利要求1-8任一所述的Doherty功率放大器。
PCT/CN2020/112739 2020-08-31 2020-08-31 一种Doherty功率放大器、印刷电路板及基站 WO2022041286A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/112739 WO2022041286A1 (zh) 2020-08-31 2020-08-31 一种Doherty功率放大器、印刷电路板及基站

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/112739 WO2022041286A1 (zh) 2020-08-31 2020-08-31 一种Doherty功率放大器、印刷电路板及基站

Publications (1)

Publication Number Publication Date
WO2022041286A1 true WO2022041286A1 (zh) 2022-03-03

Family

ID=80354444

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/112739 WO2022041286A1 (zh) 2020-08-31 2020-08-31 一种Doherty功率放大器、印刷电路板及基站

Country Status (1)

Country Link
WO (1) WO2022041286A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023197673A1 (zh) * 2022-04-12 2023-10-19 中兴通讯股份有限公司 一种doherty功率放大器、电路板组件和电子设备
WO2023226681A1 (zh) * 2022-05-25 2023-11-30 华为技术有限公司 一种光电放大电路和信号处理方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102142812A (zh) * 2010-12-17 2011-08-03 华为技术有限公司 Doherty功率放大器
CN102801387A (zh) * 2012-09-13 2012-11-28 电子科技大学 一种双模双带高效率Doherty功率放大器
CN206211949U (zh) * 2016-09-28 2017-05-31 中山大学 一种双频Doherty功率放大器
US9966903B1 (en) * 2016-12-30 2018-05-08 Nxp Usa, Inc. Doherty architecture for wideband power amplifier design

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102142812A (zh) * 2010-12-17 2011-08-03 华为技术有限公司 Doherty功率放大器
CN102801387A (zh) * 2012-09-13 2012-11-28 电子科技大学 一种双模双带高效率Doherty功率放大器
CN206211949U (zh) * 2016-09-28 2017-05-31 中山大学 一种双频Doherty功率放大器
US9966903B1 (en) * 2016-12-30 2018-05-08 Nxp Usa, Inc. Doherty architecture for wideband power amplifier design

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023197673A1 (zh) * 2022-04-12 2023-10-19 中兴通讯股份有限公司 一种doherty功率放大器、电路板组件和电子设备
WO2023226681A1 (zh) * 2022-05-25 2023-11-30 华为技术有限公司 一种光电放大电路和信号处理方法

Similar Documents

Publication Publication Date Title
CN107112953B (zh) 用于放大射频信号的功率放大器
CN103988424B (zh) 具有高功率附加效率的倒装芯片线性功率放大器
CN106537769A (zh) 与线性和高效宽带功率放大器有关的系统和方法
US7170353B2 (en) Balanced amplifier circuit and high-frequency communication apparatus
CN107222173B (zh) 基于单频线的毫米波双频Doherty功率放大器
CN112491365B (zh) 一种基于单并联谐振块的宽带Doherty功率放大器
CN106452370A (zh) 一种基于非对称结构的高回退Doherty功率放大器及其实现方法
CN104113286B (zh) 一种Doherty功率放大电路
EP3070840B1 (en) Power amplifier and power amplification method
WO2009045686A2 (en) Inverted doherty amplifier with increased off-state impedence
US20150200631A1 (en) Dual-band doherty combiner/impedance transformer circuit and doherty power amplifier including the same
JP2011015242A (ja) 高周波電力増幅器
WO2022041286A1 (zh) 一种Doherty功率放大器、印刷电路板及基站
CN216390920U (zh) Doherty射频功率放大器
CN112543002B (zh) 宽带差分Doherty功率放大器及其设计方法和应用
CN107231131A (zh) 一种可增大功率回退范围的多赫尔蒂功率放大器
US20150070094A1 (en) Doherty power amplifier with coupling mechanism independent of device ratios
CN106411265A (zh) 一种拓展带宽的非对称Doherty功率放大器及其实现方法
JP2009182635A (ja) ドハティ増幅器
JP5035846B2 (ja) ドハティ増幅回路
Piazzon et al. A method for designing broadband Doherty power amplifiers
CN210053382U (zh) 一种连续逆F类和J类混合的宽带Doherty功率放大器
CN107508560B (zh) 一种增强带宽性能的Doherty功率放大器及其实现方法
CN114094960A (zh) Mmic微波功率放大器及射频前端模组
US10224878B2 (en) Power amplification device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20950955

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20950955

Country of ref document: EP

Kind code of ref document: A1