High bandwidth load modulation power amplifier and corresponding RF front-end module

Abstract

A load modulation power amplifier is provided that has beneficial effects such as high bandwidth, high efficiency, and low loss. The present invention discloses a high-bandwidth load modulation power amplifier, which includes a main circuit power amplifier, an auxiliary circuit power amplifier, a quadrature coupler, a main circuit RF signal matching network, an auxiliary circuit RF signal matching network, and an output coupling RF signal matching network. When receiving an RF signal input, the quadrature coupler splits the input RF signal into two RF signals with a phase difference of 90 degrees, the RF signal with a phase of +45 degrees enters the main circuit power amplifier, and the RF signal with a phase of -45 degrees enters the auxiliary circuit power amplifier, and the output coupling RF signal matching network combines the main circuit signal and the auxiliary circuit signal to output an RF signal. The present invention also provides an RF front-end module and corresponding electronic device including the load modulation power amplifier.

Description

[Technical field]

[0001] The present invention relates to a high-bandwidth load modulation power amplifier, as well as to an RF front-end module and corresponding electronic device including the load modulation power amplifier, which belong to the technical field of RF integrated circuits. [Background technology]

[0002] A load modulation power amplifier is also called a Doherty power amplifier. A typical Doherty power amplifier consists of two amplifiers and an impedance inversion network, one of which is called a carrier amplifier (also called a carrier amplifier, main circuit power amplifier) ​​and the other is called a peaking amplifier (also called a peaking amplifier, auxiliary circuit power amplifier). An important feature of the Doherty power amplifier is that it can combine the asymmetric output power of the two amplifiers to realize load modulation. Specifically, at small signals (low power), only the carrier amplifier operates at a low power level. At large signals (high power), the peaking amplifier operates at a higher power level, and in this section, the carrier amplifier operates in peak efficiency mode.

[0003] On the other hand, in order to cope with the increase in data throughput of wireless communication systems, modulated signals with high spectral efficiency, i.e., peak-to-average power ratio (PAPR), are required. Therefore, in order to reduce the power consumption of wireless communication systems, the efficiency value of the power amplifier during power back-off is important. The characteristic of the load modulation type power amplifier is that it has a high efficiency value during power back-off, but due to the lack of bandwidth caused by its circuit structure, the high efficiency of the load modulation type power amplifier during power back-off can only operate normally in a narrow bandwidth. In the wide frequency band of the fifth generation (5G) mobile communication technology, for example, the frequency range of the n77 frequency band is 3.3GHz to 4.2GHz, and the frequency bandwidth is 900MHz. The load modulation power amplifier in the prior art can no longer meet the technical requirements of this bandwidth. This point will be specifically explained below.

[0004] As shown in Fig. 1, a typical example of a load modulation power amplifier in the prior art includes a main circuit power amplifier 121, an auxiliary circuit power amplifier 122, a quarter-wavelength input transmission line 123, a quarter-wavelength output transmission line 124, and an output matching network 125. Ideally, when an RF signal is input to the RF signal input port, a part of the RF signal is input to the main circuit power amplifier 121, amplified by the main circuit power amplifier, and then transmitted to the output matching network 125 via the quarter-wavelength output transmission line 124. The other part of the RF signal is input to the quarter-wavelength input transmission line 123, then transmitted to the auxiliary circuit power amplifier 122, amplified by the auxiliary circuit power amplifier 122, and then output to the output matching network 125, which combines the two signals to output an RF signal. The main circuit power amplifier is in a Class AB bias state and is turned on when the power is low, the auxiliary circuit power amplifier is in a Class C bias state and the power amplifier is turned off when the power is low, and the auxiliary circuit power amplifier turns on the amplifier to amplify the power when the input signal is sufficiently large.

[0005] In the load modulated power amplifier example above, the quarter wavelength output transmission line 124 and output matching network 125 are the points that limit the bandwidth of the circuit. At low power, the quarter wavelength output transmission line 124 must present a higher load line impedance to the main circuit power amplifier, and at high power, the quarter wavelength output transmission line 124 must present a lower load line impedance to the main circuit power amplifier. Switching the impedance transformation ratio of the quarter wavelength output transmission line 124 for each power limits the bandwidth. Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem that the present invention seeks to solve is to provide a high bandwidth load modulated power amplifier.

[0007] Another technical problem to be solved by the present invention is to provide an RF front-end module and an electrical device including the above-mentioned load modulation power amplifier. [Means for solving the problem]

[0008] To achieve the above objectives, the present invention adopts the following technical solutions:

[0009] In a first aspect according to an embodiment of the present invention, a high-bandwidth load modulation power amplifier is provided, comprising a main circuit power amplifier, an auxiliary circuit power amplifier, a quadrature coupler, a main circuit RF signal matching network, an auxiliary circuit RF signal matching network and an output coupling RF signal matching network, wherein an input end of the quadrature coupler is connected to an RF signal input end, an output end of the quadrature coupler with a +45 degree phase is connected to an input end of the main circuit power amplifier, an output end of the main circuit power amplifier is connected to the main circuit RF signal matching network, an output end of the quadrature coupler with a -45 degree phase is connected to an input end of the auxiliary circuit power amplifier, and an output end of the auxiliary circuit power amplifier is connected to the auxiliary circuit RF signal matching network.

[0010] The other end of the auxiliary circuit RF signal matching network is connected in parallel with the other end of the main circuit RF signal matching network, and then connected to the output coupling RF signal matching network, and the other end of the output coupling RF signal matching network is connected to an RF signal output end.

[0011] Preferably, the main circuit RF signal matching network, the auxiliary circuit RF signal matching network and the output coupling RF signal matching network are all constructed from lumped elements.

[0012] Preferably, the main circuit RF signal matching network is composed of a first inductor, a second inductor, a first capacitor and a second capacitor, one end of the first inductor is connected to the output end of the main circuit power amplifier, the other end of the first inductor is connected to the second inductor and the first capacitor, the other end of the first capacitor is connected to the ground end, the other end of the second inductor is connected to the second capacitor and a fifth inductor of the output coupling RF signal matching network, and the other end of the second capacitor is connected to the ground end.

[0013] Preferably, the auxiliary circuit RF signal matching network is composed of a third inductor, a fourth inductor, a third capacitor and a fourth capacitor, one end of the third capacitor is connected to the output end of the auxiliary circuit power amplifier, the other end of the third capacitor is connected to the third inductor and the fourth inductor, the other end of the third inductor is connected to the ground end, the other end of the fourth inductor is connected to the fourth capacitor and a fifth inductor of the output coupling RF signal matching network, and the other end of the fourth capacitor is connected to the ground end.

[0014] Preferably, the output coupling RF signal matching network is composed of a fifth inductor and a fifth capacitor, one end of the fifth inductor is connected to the fifth capacitor and the RF signal output terminal, and the other end of the fifth capacitor is connected to the ground terminal.

[0015] Preferably, the second capacitor in the main circuit RF signal matching network and the fourth capacitor in the auxiliary circuit RF signal matching network are integrated into one capacitor.

[0016] Preferably, the second capacitor in the main circuit RF signal matching network and the fourth inductor in the auxiliary circuit RF signal matching network can be simply removed when their resonant frequencies are equal to the operating frequency.

[0017] Preferably, the auxiliary circuit RF signal matching network is composed of a third inductor, a fourth inductor, a third capacitor and a fourth capacitor, one end of the third inductor is connected to the output end of the auxiliary circuit power amplifier, the other end of the third inductor is connected to the third capacitor and the fourth capacitor, the other end of the third capacitor is connected to the ground end, the other end of the fourth capacitor is connected to the fourth inductor and a fifth capacitor of the output coupling RF signal matching network, and the other end of the fourth inductor is connected to the ground end.

[0018] The output coupling RF signal matching network is composed of a fifth inductor and a fifth capacitor, the other end of the fifth capacitor is connected to the fifth inductor and an RF signal output terminal, and the other end of the fifth inductor is connected to a ground terminal.

[0019] In a second aspect according to an embodiment of the present invention, there is provided an RF front-end module including the above-mentioned load modulation power amplifier.

[0020] In a third aspect according to an embodiment of the present invention, there is provided an electronic device including the above-mentioned load modulation power amplifier.

[0021] Compared with the prior art, the load modulation power amplifier provided by the present invention improves the operating bandwidth by up to several times that of the prior art, and effectively improves the operating efficiency during power back-off. Meanwhile, the insertion loss of the load modulation power amplifier provided by the present invention is obviously smaller than that of similar products in the prior art, thus meeting the requirements of high bandwidth, high efficiency and low loss characteristics presented by the fifth generation (5G) mobile communication technology. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 illustrates an example of a load modulation power amplifier in the prior art. [Diagram 2] FIG. 2 is a schematic diagram illustrating a load line conversion for the load modulation power amplifier shown in FIG. [Diagram 3]2 is a schematic diagram showing a circuit in which the load line structure in the load modulation power amplifier shown in FIG. 1 is replaced with lumped elements. [Figure 4] FIG. 2 illustrates an embodiment of a load modulation power amplifier provided by the present invention. [Diagram 5] FIG. 5 is a diagram showing a modification of the load modulation power amplifier shown in FIG. [Figure 6] FIG. 6 is a diagram showing an equivalent structure for operating the modified example shown in FIG. 5 at low power consumption. [Figure 7] 5 is a diagram showing another modification of the load modulation power amplifier shown in FIG. [Figure 8] FIG. 5 is a diagram showing another modification of the load modulation power amplifier shown in FIG. [Figure 9] FIG. 13 is a diagram showing a simulation test result for the insertion loss of the load modulation power amplifier provided by the present invention. [Figure 10] FIG. 2 is a diagram showing simulation test results for efficiency values ​​of the load modulation power amplifier provided by the present invention. [Figure 11] FIG. 1 illustrates an electronic device using a load modulation power amplifier provided by the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, the technical solutions of the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

[0024] In order to more clearly explain the technical principle of the present invention, the inventor first uses Kirchhoff's theorem to analyze the load linear transformation principle. Figure 2 is a schematic diagram showing the load line transformation for the load modulation power amplifier shown in Figure 1. As shown in Figure 2, the relationship between the operating voltage and operating current of the main circuit and the operating voltage and operating current of the auxiliary circuit can be derived as follows: JPEG2025500102000002.jpg26161JPEG2025500102000003.jpg26164

[0025] Here, Vm is the operating voltage of the main circuit, I m is the operating current of the main circuit, V p is the operating voltage of the auxiliary circuit, I p is the operating current of the auxiliary circuit, I o is the output current of the main circuit after passing through the transmission line, Z o is the characteristic impedance value of the main circuit transmission line, and R is the impedance of the load.

[0026] Through calculation, the main circuit load line impedance Z m and auxiliary circuit load line impedance Z P can be obtained. JPEG2025500102000004.jpg26164JPEG2025500102000005.jpg26164

[0027] According to equation (3), when the input RF signal is a small signal (low power), the auxiliary circuit power amplifier is not turned on, i.e., I p is equal to 0. R=(1 / 2)Z o Assuming that the load line impedance of the main power amplifier is Z m is Z o 2 / R=2Z o and the load line impedance of the auxiliary circuit power amplifier is infinite. As the input RF signal gradually increases, the main circuit power amplifier becomes saturated, i.e., I m If there is no change, the auxiliary circuit power amplifier is turned on and the operating current I p When becomes larger, the load line impedance Z of the main circuit power amplifier m gradually decreases, and the load line impedance Z of the auxiliary circuit power amplifier P also gradually decreases. p =I m ,R=(1 / 2)Z o Assuming that the load line impedance of the main power amplifier is Z m =Z o 2 / RZ o =Z oand the load line impedance of the auxiliary circuit power amplifier is Z P =Z o As a result, when the input signal changes from small to large, the load line impedance of the main circuit power amplifier also changes to 2Z. o From Z o The load line impedance of the auxiliary circuit power amplifier also decreases from infinity to Z o , and the output power of the load modulation power amplifier further increases.

[0028] When the load modulation power amplifier shown in Fig. 1 receives an input of an RF signal, the quadrature coupler 126 (see Fig. 3) splits the input RF signal into two RF signals with a phase difference of 90 degrees. Here, the RF signal with a phase of +45 degrees enters the main circuit power amplifier 121, and the RF signal with a phase of -45 degrees enters the auxiliary circuit power amplifier 122. When the input RF signal is in a low power state, the auxiliary circuit power amplifier 122 is not turned on, and the main circuit presents a high load line impedance, and when the input RF signal is in a high power state, the auxiliary circuit power amplifier 122 is turned on, and both the main circuit and the auxiliary circuit present a low load line impedance.

[0029] As shown in Fig. 3, the load line structure of the load modulation power amplifier shown in Fig. 1 is replaced with lumped elements. Specifically, it includes a main circuit RF signal matching network 123 (pi-type network), an auxiliary circuit RF signal matching network 124 (LC resonant network), and an output coupling RF signal matching network 125. Here, the main circuit RF signal matching network 123 is composed of a parallel connected capacitor C1, a series connected inductor L1, and a parallel connected capacitor C2. The auxiliary circuit RF signal matching network 124 is composed of a series connected inductor L2 and a series connected capacitor C3. The output coupling RF signal matching network 125 is composed of a series connected capacitor C4, a parallel connected inductor L3, a series connected inductor L4, and a parallel connected capacitor C5.

[0030] The output coupling RF signal matching network 125 is connected to the antenna impedance R L Convert to P point impedance, Z P is generally R OPT The main circuit RF signal matching network 123 serves to replace the quarter-wave output transmission line 124 in FIG. 1 and has a characteristic impedance of R OPT When the input RF signal is low power, the impedance at point P R OPT / 2 to 2R OPT When the input RF signal is high power, the impedance at point P is increased to R by injecting an operating current from the auxiliary circuit power amplifier to point P. OPT The load line impedance of the main power amplifier is converted to 2R OPT From R OPT It decreases to.

[0031] Accordingly, the Q of the main circuit RF signal matching network 123 m The values ​​are: JPEG2025500102000006.jpg26166R L 50Ω and R OPT Assuming that the Q of the output-coupled RF signal matching network 125 is 6.25 Ω, L The value can be calculated as follows: JPEG2025500102000007.jpg26166 The auxiliary circuit RF signal matching network 124 is a high Q LC resonant network, with negligible load modulation effects.

[0032] According to the network bandwidth formula, the bandwidth (abbreviated as BW) value of the load modulation power amplifier shown in FIG. 1 can be obtained by calculating as follows: A larger value of JPEG2025500102000008.jpg26166BW indicates a wider bandwidth of the load modulation power amplifier.

[0033] In the matching network, device Qu Assuming the value is 10, the insertion loss of the load modulation power amplifier shown in Figure 1 can be calculated according to the insertion loss formula as follows: JPEG2025500102000009.jpg26166

[0034] Based on the above theoretical analysis, the present invention provides an improved load modulation power amplifier. As shown in Fig. 4, the load modulation power amplifier shown in this embodiment includes a quadrature coupler 126, a main circuit power amplifier 121, an auxiliary circuit power amplifier 122, a main circuit RF signal matching network 123, an auxiliary circuit RF signal matching network 124 and an output coupling RF signal matching network 125 to achieve higher bandwidth. Here, the input end of the quadrature coupler 126 is connected to the RF signal input end, and the output end of the quadrature coupler 126 with a +45 degree phase is connected to the input end of the main circuit power amplifier 121. The output end of the main circuit power amplifier 121 is connected to the main circuit RF signal matching network 123, and the output end of the quadrature coupler 126 with a -45 degree phase is connected to the input end of the auxiliary circuit power amplifier 122. The output end of the auxiliary circuit power amplifier 122 is connected to the auxiliary circuit RF signal matching network 124, the other end of the auxiliary circuit RF signal matching network 124 is connected in parallel to the other end of the main circuit RF signal matching network 123, and then connected to the output coupling RF signal matching network 125, the other end of the output coupling RF signal matching network 125 is connected to the RF signal output end.

[0035] In the embodiment shown in FIG. 4, the main circuit RF signal matching network 123, the auxiliary circuit RF signal matching network 124 and the output coupling RF signal matching network 125 are all composed of lumped elements, and a detailed description thereof will be given as follows.

[0036] The main circuit RF signal matching network 123 is an LCLC two-level network structure composed of a first inductor L1, a second inductor L2, a first capacitor C1 and a second capacitor C2. Here, one end of the first inductor L1 is connected to the output end of the main circuit power amplifier 121, and the other end of the first inductor L1 is connected to the second inductor L2 and the first capacitor C1. The other end of the first capacitor C1 is connected to the ground terminal GND, the other end of the second inductor L2 is connected to the second capacitor C2 and the fifth inductor L5 of the output coupling RF signal matching network 125, and the other end of the second capacitor C2 is connected to the ground terminal GND.

[0037] The auxiliary circuit RF signal matching network 124 is a CLLC two-level network structure composed of a third inductor L3, a fourth inductor L4, a third capacitor C3 and a fourth capacitor C4. Here, one end of the third capacitor C3 is connected to the output end of the auxiliary circuit power amplifier 122, and the other end of the third capacitor C3 is connected to the third inductor L3 and the fourth inductor L4. The other end of the third inductor L3 is connected to the ground end GND, the other end of the fourth inductor L4 is connected to the fourth capacitor C4 and the fifth inductor L5 of the output coupling RF signal matching network 125, and the other end of the fourth capacitor C4 is connected to the ground end GND.

[0038] The output coupling RF signal matching network 125 is an LC single-level network structure composed of a fifth inductor L5 and a fifth capacitor C5, where the other end of the fifth inductor L5 is connected to the fifth capacitor C5 and the RF signal output terminal, and the other end of the fifth capacitor C5 is connected to the ground terminal GND.

[0039] In the embodiment of the load modulation power amplifier shown in FIG. 4, when receiving an input RF signal, the quadrature coupler 126 splits the input RF signal into two RF signals with a phase difference of 90 degrees, the RF signal with a phase of +45 degrees enters the main circuit power amplifier 121, and the RF signal with a phase of -45 degrees enters the auxiliary circuit power amplifier 122. When the input RF signal is in a low power state, the auxiliary circuit power amplifier 122 is in an off state, the main circuit power amplifier 121 is in an operating state, and the main circuit presents a high load line impedance. When the input RF signal is in a high power state, the auxiliary circuit power amplifier 122 is in an operating state, and both the main circuit and the auxiliary circuit present a low load line impedance, and the output coupling RF signal matching network 125 outputs an RF signal after combining the main circuit signal and the auxiliary circuit signal.

[0040] Based on the embodiment of the load modulation power amplifier shown in Fig. 4, the present invention further provides several variants of this embodiment. For example, in the variant shown in Fig. 5, the two capacitors C2 and C4 connected to node P in Fig. 4 are integrated into one capacitor, namely the capacitor C2 in Fig. 5.

[0041] 6 is a diagram showing a simplified structure of the modified example shown in FIG. 5 when it is operated with a small signal (low power). When the input RF signal is a small signal, the auxiliary circuit power amplifier is in an off state with no output current, and the device involved in the matching of the auxiliary circuit may be equivalent to C2', and forms a pi-type network together with the output coupling RF signal matching network 125, and the antenna impedance R L The impedance at point P is 4R OPT Here, R OPT is the characteristic impedance of the main circuit RF signal matching circuit. The main circuit RF signal matching network 123 is m When the optimum impedance conversion ratio is selected to be 2, the load line impedance Z of the main circuit power amplifier 121 is m is 2R OPTWhen the input RF signal is a large signal (high power), as shown in Figure 5, after the auxiliary circuit power amplifier is turned on, it injects an operating current into point P, so that the impedance at point P is 2R. OPT The load line impedance of the main power amplifier is converted to Z m 2R OPT From R OPT At this time, the load line impedance of the auxiliary circuit power amplifier is reduced to Z P is R OPT It becomes.

[0042] To summarize the above, when the input RF signal changes from small to large, the load line impedance Z m 2R OPT From R OPT This reduces the load line impedance to a modulated level, improving the efficiency during power backoff. At the same time, the load line impedance Z P From infinity to R OPT , and thus the output power of the load modulation power amplifier increases.

[0043] Correspondingly, the Q of the main circuit RF signal matching network 123 m The values ​​are as follows: JPEG2025500102000010.jpg26165R L 50Ω and R OPT Assuming that the Q of the output-coupled RF signal matching network 125 is 6.25 Ω, L The value can be calculated as follows: JPEG2025500102000011.jpg26165

[0044] According to the network bandwidth formula, the bandwidth (BW) of the load modulation power amplifier in this embodiment can be calculated as follows: JPEG2025500102000012.jpg27165, where f c is the operating frequency.

[0045] From this, it can be seen that the bandwidth of the load modulation power amplifier provided by the embodiment of the present invention is three times that of the existing load modulation power amplifier shown in FIG.

[0046] In the matching network, the Q of the device u Assuming the value is 10, the insertion loss of the load modulation power amplifier shown in FIG. 4 can be calculated according to the insertion loss formula as follows: JPEG2025500102000013.jpg26165

[0047] From this, the insertion loss of the load modulation power amplifier provided by the embodiment of the present invention is clearly reduced compared to the insertion loss of −1.39 dBc of the prior art load modulation power amplifier shown in FIG.

[0048] The above calculation results regarding the bandwidth and insertion loss of the load modulation power amplifier provided by the present invention are based on the main circuit load line impedance Z m When the impedance transformation ratio is 2, the main circuit RF signal matching network 123 selects an optimal impedance transformation ratio of 2. In other embodiments of the present invention, the impedance transformation ratio may be selected to be other values ​​such as 1.8 or 2.2, and as can be seen from the calculation based on the above equations (11) and (12), the bandwidth and insertion loss value of the load modulation power amplifier are improved in the range of 1 to 3 times (compared with the prior art).

[0049] Figure 7 shows another modified example of the load modulation power amplifier shown in Figure 4. In this modified example, the specific changes are that the auxiliary circuit RF signal matching network 124 is changed from the CLLC two-level network structure in Figure 4 to the LCCL two-level network structure in Figure 7, and the output coupling RF signal matching network 125 is changed from the LC single-level network structure in Figure 4 to the CL single-level network structure in Figure 7. Both the auxiliary circuit RF signal matching network 124 and the output coupling RF signal matching network 125 are composed of lumped elements.

[0050] Specifically, the auxiliary circuit RF signal matching network 124 is composed of a third inductor L3, a fourth inductor L4, a third capacitor C3, and a fourth capacitor C4. Here, one end of the third inductor L3 is connected to the output end of the auxiliary circuit power amplifier 122, and the other end of the third inductor L3 is connected to the third capacitor C3 and the fourth capacitor C4. The other end of the third capacitor C3 is connected to the ground end GND, the other end of the fourth capacitor C4 is connected to the fourth inductor L4 and a fifth capacitor C5 of the output coupling RF signal matching network 125, and the other end of the fourth inductor L4 is connected to the ground end GND.

[0051] On the other hand, the output coupling RF signal matching network 125 is composed of a fifth inductor L5 and a fifth capacitor C5. The other end of the fifth capacitor C5 is connected to the fifth inductor L5 and the RF signal output terminal, and the other end of the fifth inductor L5 is connected to the ground terminal GND.

[0052] Figure 8 is another modification of the load modulation power amplifier shown in Figure 4. In this modification, the capacitor C2 and the inductor L4 can be simply removed by designing their resonant frequencies to be close to or equal to the operating frequency. In another modification, the output coupling RF signal matching network 125 can be expanded to a matching network of a series connected inductor L5, a parallel connected capacitor C5, a series connected capacitor C6, and a parallel connected inductor L6 to further expand the matching bandwidth.

[0053] In addition, each embodiment or modification of the present invention is described in a related manner, and the same or similar parts between each embodiment or modification can be mutually referred to. Each embodiment or modification is mainly described with respect to the difference from other embodiments, but they are all realized based on the operating principle of the load modulation power amplifier, and detailed description is omitted in this specification.

[0054] In order to embody the actual technical effect of the load modulation power amplifier provided by the embodiment of the present invention, the inventors have carried out an actual simulation test in the n77 frequency band. Figure 9 shows a comparison between the insertion loss of the load modulation power amplifier provided by the present invention and the insertion loss of the load modulation power amplifier in the prior art. Here, curve A shows the simulation test result for the load modulation power amplifier provided by the present invention, and curve B shows the simulation test result for the load modulation power amplifier in the prior art. As can be seen from Figure 9, the insertion loss value of curve A is obviously smaller than the insertion loss value of curve B, and curve A shows a higher band characteristic than curve B.

[0055] Figure 10 shows a comparison of the efficiency value of the load modulation power amplifier provided by the present invention with the efficiency value of the load modulation power amplifier in the prior art. Here, curve A shows the simulation test result for the load modulation power amplifier provided by the present invention, and curve B shows the simulation test result for the load modulation power amplifier in the prior art. As can be seen from Figure 10, the efficiency value of curve A is obviously higher than that of curve B, and curve A shows a higher bandwidth characteristic than curve B.

[0056] The load modulation power amplifier provided by the present invention can be applied to various RF front-end modules, which can include other existing common devices such as an RF front-end receiving link, an RF front-end transmitting link, etc., and detailed description is omitted in this specification.

[0057] In addition, the load modulation power amplifier provided by the present invention may be applied to electronic devices as an important part of a communication component. The electronic devices referred to herein refer to computer devices that can be used in a mobile environment and support various communication standards such as GSM, EDGE, TD_SCDMA, TDD_LTE, FDD_LTE, 5G, etc., including mobile phones, laptop computers, tablet computers, vehicle network terminals, etc. In addition, the technical solution provided by the present invention is also applicable to other RF front-end module applications, such as communication base stations.

[0058] As shown in FIG. 11, the electronic device includes at least a processor and a memory, and may further include a communication component, a sensor component, a power component, a multimedia component, and an input / output interface based on actual demand. Here, the memory, the communication component, the sensor component, the power component, the multimedia component, and the input / output interface are all connected to the processor. The memory can be a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic memory, a flash memory, etc., and the processor can be a central processing unit (CPU), a graphics processor (GPU), a field programmable logic gate array (FPGA), an application specific integrated circuit (ASIC), a digital signal processing (DSP) chip, etc. Other communication components, sensor components, power components, multimedia components, etc. can all be realized by adopting general-purpose parts, and detailed explanations are omitted here.

[0059] Compared with the prior art, the load modulation power amplifier provided by the present invention can improve the operating bandwidth by up to several times than the prior art, and effectively improve the operating efficiency during power back-off. Meanwhile, the insertion loss of the load modulation power amplifier provided by the present invention is obviously smaller than that of similar products in the prior art, thus meeting the requirements of high bandwidth, high efficiency and low loss characteristics presented by the fifth generation (5G) mobile communication technology.

[0060] Above is a detailed description of the high bandwidth load modulation power amplifier and corresponding RF front-end module provided by the present invention. Any obvious modifications made to the present invention by those skilled in the art without departing from the essence of the present invention will fall within the scope of protection of the patent right of the present invention.

Claims

1. A high bandwidth load modulation power amplifier comprising a main circuit power amplifier and an auxiliary circuit power amplifier, a quadrature coupler, a main circuit RF signal matching network, an auxiliary circuit RF signal matching network, and an output coupling RF signal matching network; an input end of the quadrature coupler is connected to an RF signal input end, a +45 degree phase output end of the quadrature coupler is connected to an input end of the main circuit power amplifier, an output end of the main circuit power amplifier is connected to the main circuit RF signal matching network, a -45 degree phase output end of the quadrature coupler is connected to an input end of the auxiliary circuit power amplifier, and an output end of the auxiliary circuit power amplifier is connected to the auxiliary circuit RF signal matching network; the other end of the auxiliary circuit RF signal matching network is connected in parallel with the other end of the main circuit RF signal matching network, and then connected to the output coupling RF signal matching network, the other end of the output coupling RF signal matching network being connected to an RF signal output end.

2. 2. The load modulation power amplifier of claim 1, wherein the main circuit RF signal matching network, the auxiliary circuit RF signal matching network and the output coupling RF signal matching network are all constructed of lumped elements.

3. 3. The load modulation power amplifier according to claim 2, wherein the main circuit RF signal matching network is composed of a first inductor, a second inductor, a first capacitor and a second capacitor, one end of the first inductor is connected to the output end of the main circuit power amplifier, the other end of the first inductor is connected to the second inductor and the first capacitor, the other end of the first capacitor is connected to the ground end, the other end of the second inductor is connected to the second capacitor and a fifth inductor of the output coupling RF signal matching network, and the other end of the second capacitor is connected to the ground end.

4. 3. The load modulation power amplifier of claim 2, wherein the auxiliary circuit RF signal matching network is composed of a third inductor, a fourth inductor, a third capacitor and a fourth capacitor, one end of the third capacitor is connected to the output end of the auxiliary circuit power amplifier, the other end of the third capacitor is connected to the third inductor and the fourth inductor, the other end of the third inductor is connected to a ground end, the other end of the fourth inductor is connected to a fourth capacitor and a fifth inductor of the output coupling RF signal matching network, and the other end of the fourth capacitor is connected to a ground end.

5. 3. The load modulation power amplifier of claim 2, wherein the output coupling RF signal matching network is composed of a fifth inductor and a fifth capacitor, one end of the fifth inductor is connected to the fifth capacitor and an RF signal output terminal, and the other end of the fifth capacitor is connected to a ground terminal.

6. 5. The load modulation power amplifier according to claim 3, wherein the second capacitor in the main circuit RF signal matching network and the fourth capacitor in the auxiliary circuit RF signal matching network are integrated into one capacitor.

7. 5. The load modulation power amplifier according to claim 3, wherein the second capacitor in the main circuit RF signal matching network and the fourth inductor in the auxiliary circuit RF signal matching network can be simply removed when their resonant frequencies are equal to the operating frequency.

8. the auxiliary circuit RF signal matching network is composed of a third inductor, a fourth inductor, a third capacitor, and a fourth capacitor, one end of the third inductor is connected to the output end of the auxiliary circuit power amplifier, the other end of the third inductor is connected to the third capacitor and the fourth capacitor, the other end of the third capacitor is connected to a ground end, the other end of the fourth capacitor is connected to the fourth inductor and a fifth capacitor of an output coupling RF signal matching network, and the other end of the fourth inductor is connected to a ground end; 3. The load modulation power amplifier of claim 2, wherein the output coupling RF signal matching network is composed of a fifth inductor and a fifth capacitor, the other end of the fifth capacitor is connected to the fifth inductor and an RF signal output terminal, and the other end of the fifth inductor is connected to a ground terminal.

9. An RF front-end module comprising a load modulation power amplifier according to any one of claims 1 to 8.

10. An electronic device comprising a load modulation power amplifier according to any one of claims 1 to 8.

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