Radio frequency power amplifier circuit having harmonic suppression function, and radio frequency chip
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-30
- Publication Date
- 2026-08-13
Smart Images
Figure CN2026076069_13082026_PF_FP_ABST
Abstract
Description
RF power amplifier circuit and RF chip with harmonic suppression function Technical Field
[0001] This utility model applies to the field of radio frequency technology, and particularly relates to a radio frequency power amplifier circuit and radio frequency chip with harmonic suppression function. Background Technology
[0002] In mobile communication systems, radio frequency power amplifiers (PAs) play a crucial role. The performance of RF power amplifiers directly affects the quality of RF signals. In particular, the 5G communication systems that are now widely used have high requirements for the linearity, power consumption, and harmonics of RF signals. Therefore, it is necessary to improve the design, layout, and structure of RF power amplifiers to meet the needs of 5G communication.
[0003] Figure 1 shows the structure design of an RF power amplifier circuit in an existing 5G communication system. The diagram illustrates a two-stage power amplifier design, including input matching, first and second stage bias circuits, two power supplies (VCC1, VCC2), inter-stage matching, and output matching. Input matching performs impedance matching at the amplifier's input, reducing RF input reflection. The two-stage bias circuits provide reasonable bias operating points for the two amplifier stages. Capacitors C1 and L1 form a filter circuit; L1 is a choke inductor that conducts DC current while impeding RF current, and C1 conducts leaked RF signals to ground, reducing the impact of RF signals on the DC circuit. Inter-stage matching, composed of capacitor C2, inductor L2, and capacitor C3, matches the output impedance of the first-stage power amplifier with the input impedance of the second-stage power amplifier, allowing the RF signal to smoothly exit from the first-stage power amplifier and enter the second-stage power amplifier. Output matching matches the power amplifier impedance to a reasonable value, enabling the power amplifier to output a normal RF signal.
[0004] However, the interstage matching circuits in existing RF power amplifiers have narrow RF matching bandwidth in practical designs, which has a significant impact on linearity and power consumption. They cannot meet the design requirements of high efficiency and high linearity, and their harmonic suppression is poor, making it difficult to achieve high performance with low harmonics.
[0005] Utility Model Content
[0006] This invention aims to solve the technical problems of narrow matching bandwidth and poor harmonic suppression performance of existing RF power amplifiers' interstage matching structures.
[0007] To solve the above-mentioned technical problems, in a first aspect, this utility model provides a radio frequency power amplifier circuit with harmonic suppression function. The radio frequency power amplifier circuit includes an input matching unit, a first-stage power amplifier unit, a first-stage bias unit, a first-stage power supply unit, an inter-stage matching unit, a second-stage power amplifier unit, a second-stage bias unit, a second-stage power supply unit, and an output matching unit.
[0008] The first end of the input matching unit serves as the input end of the RF power amplifier circuit for connecting to an external RF signal, and the second end of the input matching unit is connected to the input end of the first-stage power amplifier unit. The input matching unit is used to provide impedance matching for the input end of the first-stage power amplifier unit.
[0009] The first-stage bias unit is used to provide a bias voltage for the first-stage power amplifier unit;
[0010] The first end of the first-stage power supply unit is used to connect to the first external power source, and the second end of the first-stage power supply unit is connected to the output end of the first-stage power amplifier unit. The first-stage power supply unit is used to provide DC power to the first-stage power amplifier unit and to perform harmonic suppression.
[0011] The first end of the interstage matching unit is connected to the output end of the first stage power amplifier unit, and the second end of the interstage matching unit is connected to the input end of the second stage power amplifier unit. The interstage matching unit is used to provide impedance matching and harmonic suppression for the output end of the first stage power amplifier unit and the input end of the second stage power amplifier unit.
[0012] The second-stage bias unit is used to provide bias voltage for the second-stage power amplifier unit;
[0013] The first end of the second-stage power supply unit is used to connect to the second external power supply, and the second end of the second-stage power supply unit is connected to the output end of the second-stage power amplifier unit. The second-stage power supply unit is used to provide DC power to the second-stage power amplifier unit.
[0014] The first end of the output matching unit is connected to the output end of the second stage power amplifier unit, the second end of the output matching unit serves as the output end of the RF power amplifier circuit for outputting RF amplified signals, and the output matching unit is used to provide impedance matching for the output end of the second stage power amplifier unit.
[0015] The first-stage power supply unit includes a first capacitor, a second capacitor, a first inductor, and a second inductor. The first terminal of the first capacitor serves as the first terminal of the first-stage power supply unit, and the second terminal of the first capacitor is grounded.
[0016] The first end of the first inductor is connected to the second end of the first capacitor, and the second end of the first inductor is connected to the first end of the second inductor and the first end of the second capacitor, respectively.
[0017] The second end of the second inductor serves as the second end of the first-stage power supply unit;
[0018] The second terminal of the second capacitor is grounded.
[0019] Furthermore, the interstage matching unit includes a third capacitor, a fourth capacitor, a fifth capacitor, a third inductor, and a fourth inductor; the first terminal of the third capacitor serves as the first terminal of the interstage matching unit, and the second terminal of the third capacitor is connected to the first terminal of the third inductor;
[0020] The second terminal of the third inductor is grounded;
[0021] The first terminal of the fourth capacitor is connected to the first terminal of the third capacitor, and the second terminal of the fourth capacitor is connected to the first terminal of the fourth inductor and the first terminal of the fifth capacitor, respectively.
[0022] The second terminal of the fourth inductor is grounded;
[0023] The second terminal of the fifth capacitor serves as the second terminal of the interstage matching unit.
[0024] Furthermore, the second-stage power supply unit includes a sixth capacitor and a fifth inductor; the first terminal of the sixth capacitor serves as the first terminal of the second-stage power supply unit, and the second terminal of the sixth capacitor is grounded;
[0025] The first end of the fifth inductor is connected to the first end of the sixth capacitor, and the second end of the fifth inductor serves as the second end of the second-stage power supply unit.
[0026] Furthermore, the second capacitor is an on-chip capacitor, and the second inductor is an on-chip inductor.
[0027] Furthermore, the third capacitor is an on-chip capacitor, and the third inductor is an on-chip inductor.
[0028] Secondly, this utility model also provides an RF chip, including an RF power amplifier circuit with harmonic suppression function as described in any of the above claims.
[0029] The beneficial effects achieved by this utility model are that it proposes a radio frequency power amplifier circuit with harmonic suppression function. The radio frequency power amplifier circuit uses LC type notch circuits in both the power supply unit and the interstage matching unit, thereby achieving second, third and higher order harmonic suppression in the radio frequency power amplifier circuit. At the same time, the LC circuit structure in the power supply unit and the interstage matching unit also broadens the bandwidth of the interstage matching, thereby improving the linearity of the multi-stage power amplifier unit. Attached Figure Description
[0030] Figure 1 is a schematic diagram of the existing radio frequency power amplifier circuit structure;
[0031] Figure 2 is a schematic diagram of the radio frequency power amplifier circuit with harmonic suppression function provided in the embodiment of this utility model. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0033] Specifically, please refer to Figure 2. Figure 2 is a schematic diagram of the structure of the radio frequency power amplifier circuit with harmonic suppression function provided in this embodiment of the present invention. The radio frequency power amplifier circuit 100 includes an input matching unit 101, a first-stage power amplifier unit 102, a first-stage bias unit 103, a first-stage power supply unit 104, an inter-stage matching unit 105, a second-stage power amplifier unit 106, a second-stage bias unit 107, a second-stage power supply unit 108, and an output matching unit 109.
[0034] In this embodiment of the present invention, both the first-stage power amplifier unit 102 and the second-stage power amplifier unit 106 are transistor structures. The first-stage power amplifier unit 102 is represented as PA1, and the second-stage power amplifier unit 106 is represented as PA2. The base of the transistor serves as the input terminal, the collector serves as the output terminal, and the emitter serves as the ground terminal. It is understood that in possible implementations, the power amplifier unit can also be implemented using a triode, and its connection relationship is similar to that of this embodiment of the present invention. The specific type of power amplifier unit is not limited in this embodiment of the present invention.
[0035] Specifically, in this embodiment of the present invention, the first end of the input matching unit 101 serves as the input end of the radio frequency power amplifier circuit 100 for connecting to an external radio frequency signal RFin, the second end of the input matching unit 101 is connected to the input end of the first stage power amplifier unit 102, and the input matching unit 101 is used to provide impedance matching for the input end of the first stage power amplifier unit 102.
[0036] The first-stage bias unit 103 is used to provide a bias voltage BIAS1 for the first-stage power amplifier unit 102;
[0037] The first end of the first stage power supply unit 104 is used to connect to the first external power supply VCC1, and the second end of the first stage power supply unit 104 is connected to the output end of the first stage power amplifier unit 102. The first stage power supply unit 104 is used to provide DC power supply to the first stage power amplifier unit 102 and perform harmonic suppression.
[0038] The first end of the interstage matching unit 105 is connected to the output end of the first stage power amplifier unit 102, and the second end of the interstage matching unit 105 is connected to the input end of the second stage power amplifier unit 106. The interstage matching unit 105 is used to provide impedance matching and harmonic suppression for the output end of the first stage power amplifier unit 102 and the input end of the second stage power amplifier unit 106.
[0039] The second-stage bias unit 107 is used to provide a bias voltage BIAS2 for the second-stage power amplifier unit 106;
[0040] The first end of the second-stage power supply unit 108 is used to connect to the second external power supply VCC2, and the second end of the second-stage power supply unit 108 is connected to the output end of the second-stage power amplifier unit 106. The second-stage power supply unit 108 is used to provide DC power to the second-stage power amplifier unit 106.
[0041] The first end of the output matching unit 109 is connected to the output end of the second stage power amplifier unit 106, the second end of the output matching unit 109 serves as the output end of the RF power amplifier circuit 100 for outputting the RF amplified signal RFout, and the output matching unit 109 is used to provide impedance matching for the output end of the second stage power amplifier unit 106.
[0042] Specifically, the first-stage power supply unit 104 includes a first capacitor C1, a second capacitor C2, a first inductor L1 and a second inductor L2. The first end of the first capacitor C1 serves as the first end of the first-stage power supply unit 104 and is connected to the first external power supply VCC1. The second end of the first capacitor C1 is grounded.
[0043] The first end of the first inductor L1 is connected to the second end of the first capacitor C1, and the second end of the first inductor L1 is connected to the first end of the second inductor L2 and the first end of the second capacitor C2.
[0044] The second end of the second inductor L2 is connected to the output end of the first stage power amplifier unit 102 as the second end of the first stage power supply unit 104;
[0045] The second terminal of the second capacitor C2 is grounded.
[0046] During implementation, the second capacitor C2 and the second inductor L2 together form an LC notch filter network. By adjusting the capacitance value of the second capacitor C2 and the inductance value of the second inductor L2, the resonant point of the LC notch filter network is modulated to the third or higher harmonic frequency point, thereby suppressing the third or higher harmonics and optimizing the third or higher harmonic performance of the RF power amplifier circuit 100.
[0047] The interstage matching unit 105 includes a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a third inductor L3, and a fourth inductor L4; the first end of the third capacitor C3 serves as the first end of the interstage matching unit 105 and is connected to the output end of the first stage power amplifier unit 102, and the second end of the third capacitor C3 is connected to the first end of the third inductor L3.
[0048] The second terminal of the third inductor L3 is grounded;
[0049] The first terminal of the fourth capacitor C4 is connected to the first terminal of the third capacitor C3, and the second terminal of the fourth capacitor C4 is connected to the first terminal of the fourth inductor L4 and the first terminal of the fifth capacitor C5, respectively.
[0050] The second terminal of the fourth inductor L4 is grounded;
[0051] The second terminal of the fifth capacitor C5 is connected to the input terminal of the second stage power amplifier unit 106 as the second terminal of the interstage matching unit 105.
[0052] During implementation, the third inductor L3 and the third capacitor C3 together form an LC notch filter network. By adjusting the capacitance value of the third capacitor C3 and the inductance value of the third inductor L3, the resonant point of the LC notch filter network is tuned to the second harmonic frequency, thereby suppressing the second harmonic and optimizing the second harmonic performance of the RF power amplifier circuit 100. On the other hand, to ensure interstage matching is available, the fourth capacitor C4, the fourth inductor L4, and the fifth capacitor C5 together form a T-type matching network, and the impedance point after the third inductor L3 and the third capacitor C3 is matched to the input impedance of the second-stage power amplifier unit 106.
[0053] Furthermore, based on the circuit structure of the first-stage power supply unit 104 and the inter-stage matching unit 105 in this embodiment of the present invention, the second capacitor C2, the second inductor L2, the third inductor L3, and the third capacitor C3 will also participate in the inter-stage matching between the two power amplifier units. This design can widen the impedance matching bandwidth from the output terminal of the first-stage power amplifier unit 102 to the input terminal of the second-stage power amplifier unit 106, so that the optimal efficiency impedance point and the optimal linearity impedance point of the first-stage power amplifier unit 102 can be matched to the optimal input impedance point of the second-stage power amplifier unit 106, thereby significantly improving the linearity of the entire RF power amplifier circuit 100. When inputting 5G NR broadband signals, the linearity advantage is even more obvious.
[0054] The second-stage power supply unit 108 includes a sixth capacitor C6 and a fifth inductor L5. The first end of the sixth capacitor C6 is connected to the second external power supply VCC2 as the first end of the second-stage power supply unit 108, and the second end of the sixth capacitor C6 is grounded.
[0055] The first end of the fifth inductor L5 is connected to the first end of the sixth capacitor C6, and the second end of the fifth inductor L5 is connected to the output end of the second stage power amplifier unit 106 as the second end of the second stage power supply unit 108.
[0056] In this embodiment of the present invention, preferably, in order not to excessively increase the circuit board area occupied by the RF matching structure, the second capacitor C2 is an on-chip capacitor, and the second inductor L2 is an on-chip inductor. Similarly, the third capacitor C3 is an on-chip capacitor, and the third inductor L3 is an on-chip inductor.
[0057] This invention also provides an RF chip, including the RF power amplifier circuit with harmonic suppression function as described in the above embodiment. It is understood that the RF chip implemented based on this RF power amplifier circuit 100 has a higher matching bandwidth and better power amplifier linearity performance.
[0058] The beneficial effects achieved by this utility model are that it proposes a radio frequency power amplifier circuit with harmonic suppression function. The radio frequency power amplifier circuit uses LC type notch circuits in both the power supply unit and the interstage matching unit, thereby achieving second, third and higher order harmonic suppression in the radio frequency power amplifier circuit. At the same time, the LC circuit structure in the power supply unit and the interstage matching unit also broadens the bandwidth of the interstage matching, thereby improving the linearity of the multi-stage power amplifier unit.
[0059] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0060] The embodiments of the present utility model have been described above with reference to the accompanying drawings. The disclosed embodiments are merely preferred embodiments of the present utility model. However, the present utility model is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many equivalent changes under the guidance of the present utility model without departing from the spirit and scope of the claims. All such changes are within the protection scope of the present utility model.
Claims
1. A radio frequency power amplifier circuit with harmonic suppression function, characterized in that, The radio frequency power amplifier circuit includes an input matching unit, a first-stage power amplifier unit, a first-stage bias unit, a first-stage power supply unit, an inter-stage matching unit, a second-stage power amplifier unit, a second-stage bias unit, a second-stage power supply unit, and an output matching unit. The first end of the input matching unit serves as the input end of the RF power amplifier circuit for connecting to an external RF signal, and the second end of the input matching unit is connected to the input end of the first-stage power amplifier unit. The input matching unit is used to provide impedance matching for the input end of the first-stage power amplifier unit. The first-stage bias unit is used to provide a bias voltage for the first-stage power amplifier unit; The first end of the first-stage power supply unit is used to connect to the first external power source, and the second end of the first-stage power supply unit is connected to the output end of the first-stage power amplifier unit. The first-stage power supply unit is used to provide DC power to the first-stage power amplifier unit and to perform harmonic suppression. The first end of the interstage matching unit is connected to the output end of the first stage power amplifier unit, and the second end of the interstage matching unit is connected to the input end of the second stage power amplifier unit. The interstage matching unit is used to provide impedance matching and harmonic suppression for the output end of the first stage power amplifier unit and the input end of the second stage power amplifier unit. The second-stage bias unit is used to provide bias voltage for the second-stage power amplifier unit; The first end of the second-stage power supply unit is used to connect to the second external power supply, and the second end of the second-stage power supply unit is connected to the output end of the second-stage power amplifier unit. The second-stage power supply unit is used to provide DC power to the second-stage power amplifier unit. The first end of the output matching unit is connected to the output end of the second stage power amplifier unit, the second end of the output matching unit serves as the output end of the RF power amplifier circuit for outputting RF amplified signals, and the output matching unit is used to provide impedance matching for the output end of the second stage power amplifier unit. The first-stage power supply unit includes a first capacitor, a second capacitor, a first inductor, and a second inductor. The first terminal of the first capacitor serves as the first terminal of the first-stage power supply unit, and the second terminal of the first capacitor is grounded. The first end of the first inductor is connected to the second end of the first capacitor, and the second end of the first inductor is connected to the first end of the second inductor and the first end of the second capacitor, respectively. The second end of the second inductor serves as the second end of the first-stage power supply unit; The second terminal of the second capacitor is grounded.
2. The radio frequency power amplifier circuit with harmonic suppression function according to claim 1, characterized in that, The interstage matching unit includes a third capacitor, a fourth capacitor, a fifth capacitor, a third inductor, and a fourth inductor; the first terminal of the third capacitor serves as the first terminal of the interstage matching unit, and the second terminal of the third capacitor is connected to the first terminal of the third inductor. The second terminal of the third inductor is grounded; The first terminal of the fourth capacitor is connected to the first terminal of the third capacitor, and the second terminal of the fourth capacitor is connected to the first terminal of the fourth inductor and the first terminal of the fifth capacitor, respectively. The second terminal of the fourth inductor is grounded; The second terminal of the fifth capacitor serves as the second terminal of the interstage matching unit.
3. The radio frequency power amplifier circuit with harmonic suppression function according to claim 1, characterized in that, The second-stage power supply unit includes a sixth capacitor and a fifth inductor; the first terminal of the sixth capacitor serves as the first terminal of the second-stage power supply unit, and the second terminal of the sixth capacitor is grounded. The first end of the fifth inductor is connected to the first end of the sixth capacitor, and the second end of the fifth inductor serves as the second end of the second-stage power supply unit.
4. The radio frequency power amplifier circuit with harmonic suppression function according to claim 1, characterized in that, The second capacitor is an on-chip capacitor, and the second inductor is an on-chip inductor.
5. The radio frequency power amplifier circuit with harmonic suppression function according to claim 2, characterized in that, The third capacitor is an on-chip capacitor, and the third inductor is an on-chip inductor.
6. A radio frequency chip, characterized in that, Includes the radio frequency power amplifier circuit with harmonic suppression function as described in any one of claims 1-5.