Radio frequency power amplification circuit based on balanced power amplification structure

Abstract

The utility model provides a radio frequency power amplification circuit based on a balanced power amplification structure, which comprises a first orthogonal coupler, a second orthogonal coupler, a third orthogonal coupler and a fourth orthogonal coupler, the first balance amplification module receives one path of orthogonal radio frequency signal and outputs a first amplification signal; the second balance amplification module is used for receiving the other path of orthogonal radio frequency signal and outputting a second amplification signal; a second quadrature coupler receiving the first amplified signal and the second amplified signal which are orthogonal and generating a single-ended radio frequency output; wherein the first quadrature coupler comprises an input transformer comprising a first winding and a second winding, an input capacitor and an input resistor, the first winding is connected between the single-ended radio frequency input and the input end of the first balanced amplification module, and the input capacitor is connected between the single-ended radio frequency input and the input end of the second balanced amplification module. One end of the second winding is connected between the input capacitor and the input end of the second balance amplification module, and the other end of the second winding is grounded through the input resistor.

Description

Technical Field

[0001] The utility model relates to the field of radio frequency integrated circuits, and in particular to a radio frequency power amplifier circuit based on a balanced power amplifier structure. Background Art

[0002] In practical 5G applications, the n41 and n77 frequency bands must support the functional requirements of mobile high-power user equipment (HPUE). To meet HPUE requirements, mobile terminal antenna transmit power must be increased by 3dB to 26dBm. To achieve higher output power, there are two common approaches: increasing the output voltage and increasing the output current. Increasing the output voltage can be achieved by boosting the battery voltage through DC-DC conversion, but this increased voltage can easily damage the power amplifier.

[0003] Therefore, a radio frequency power amplifier circuit with small footprint, wide output bandwidth and high output power is desired. Utility Model Content

[0004] The technical solution of the utility model adopts an input quadrature coupler and an output quadrature coupler based on a transformer to replace the 90-degree bridge of a traditional balanced power amplifier.

[0005] The technical solution of the utility model has a compact structure, is easy to integrate, and occupies a small volume; in addition, it has a wide output bandwidth and high output power, and is suitable for use in mobile terminal equipment.

[0006] One aspect of the present invention provides a radio frequency power amplifier circuit, comprising: a first orthogonal coupler configured to receive a single-ended radio frequency input and output two orthogonal radio frequency signals; a first balanced amplifier module configured to receive one orthogonal radio frequency signal from the first orthogonal coupler, amplify the one orthogonal radio frequency signal, and output a first amplified signal; a second balanced amplifier module configured to receive another orthogonal radio frequency signal from the first orthogonal coupler, amplify the another orthogonal radio frequency signal, and output a second amplified signal; and a second orthogonal coupler configured to receive the first amplified signal and the second amplified signal in quadrature and generate a single-ended radio frequency output. The first orthogonal coupler comprises: an input transformer including a first winding and a second winding, an input capacitor, and an input resistor, wherein the first winding is connected between the single-ended radio frequency input and the input of the first balanced amplifier module, the input capacitor is connected between the single-ended radio frequency input and the input of the second balanced amplifier module, one end of the second winding is connected between the input capacitor and the input of the second balanced amplifier module, and the other end of the second winding is grounded via the input resistor.

[0007] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the second orthogonal coupler includes: an output transformer including a third winding and a fourth winding, and an output resistor, wherein one end of the third winding is connected to the single-ended radio frequency output, the other end of the third winding is connected to the second balanced amplifier module, one end of the fourth winding is connected to the first balanced amplifier module, and the other end of the fourth winding is grounded through the output resistor.

[0008] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the first balanced amplification module includes a first input matching network, a first amplifier, and a first output matching network, and wherein the second balanced amplification module includes a second input matching network, a second amplifier, and a second output matching network.

[0009] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein one or more of the first input matching network, the first output matching network, the second input matching network, and the second output matching network includes a matching transformer.

[0010] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein one or more of the first input matching network, the first output matching network, the second input matching network, and the second output matching network includes an LC network.

[0011] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the first amplifier and the second amplifier are formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor.

[0012] One aspect of the present invention provides a radio frequency power amplifier circuit, further comprising a filter and a switch module connected between the one end of the third winding and the single-ended radio frequency output, wherein the filter and the switch module are connected in series.

[0013] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the input transformer is formed by a rectangular pattern of two layers of metal structure.

[0014] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the output transformer is formed by a pattern of a three-layer metal structure.

[0015] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the inductor in the LC network is formed by a combination of a bonding wire and a substrate microstrip line.

[0016] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the radio frequency power amplifier circuit is packaged through a multi-layer substrate package for multiple chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram showing a conventional Doherty power amplifier structure;

[0018] Figure 2 is a schematic diagram showing a conventional balanced power amplifier structure;

[0019] Figure 3 1 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model;

[0020] Figure 4 1 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model;

[0021] Figure 5 1 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model;

[0022] Figures 6A-6C is a schematic diagram showing an implementation of the transformer T1 in the orthogonal coupler 1 according to an embodiment of the present utility model;

[0023] Figures 7A-7C is a schematic diagram showing an implementation of the transformer T2 in the orthogonal coupler 2 according to an embodiment of the present utility model;

[0024] Figure 8 1 is a phase-frequency diagram showing the orthogonal coupler 1 according to an embodiment of the present invention;

[0025] Figure 9 is a schematic diagram showing an example implementation of a matching network of a radio frequency power amplifier circuit according to an embodiment of the present utility model;

[0026] Figure 10 is a plan view showing a multi-chip package of a Doherty radio frequency power amplifier according to an embodiment of the present invention; and

[0027] Figure 11 FIG. 1 is a side view showing a multi-chip package of a Doherty radio frequency power amplifier according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] Before proceeding with the detailed description below, it may be helpful to set forth the definitions of certain words and phrases used throughout this patent document. The terms "couple," "connect," and their derivatives refer to any direct or indirect communication or connection between two or more elements, regardless of whether those elements are in physical contact with each other. The terms "transmit," "receive," and "communicate," and their derivatives, encompass both direct and indirect communication. The terms "include," "comprise," and their derivatives, mean including, but not limited to. The term "or" is inclusive, meaning and / or. The phrase "associated with..." and its derivatives mean including, included within, interconnected, containing, contained within, connected or connected with, coupled or coupled with, communicate with, cooperate with, intertwine, juxtapose, approach, bound or bound with, have, have an attribute of, have a relationship with, or have a relationship with, etc. The term "controller" refers to any device, system, or portion thereof that controls at least one operation. Such a controller may be implemented using hardware, or a combination of hardware and software and / or firmware. The functionality associated with any particular controller may be centralized or distributed, whether local or remote. The phrase "at least one of," when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one of the items in the list may be needed. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A, B, and C.

[0029] Definitions for other specific words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior and future uses of such defined words and phrases.

[0030] In this patent document, the application combination of modules and the division level of sub-modules are only used for illustration. Without departing from the scope of this disclosure, the application combination of modules and the division level of sub-modules can have different forms.

[0031] The technical solution of the utility model adopts an input quadrature coupler and an output quadrature coupler based on a transformer to replace the 90-degree bridge of a traditional balanced power amplifier.

[0032] The technical solution of the utility model has a compact structure, is easy to integrate, and occupies a small volume; in addition, it has a wide output bandwidth and high output power, and is suitable for use in mobile terminal equipment.

[0033] Figure 3 Schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model.

[0034] refer to Figure 3According to an embodiment of the present invention, the radio frequency power amplifier circuit includes an orthogonal coupler 1, a first balanced amplifier module, a second balanced amplifier module, and an orthogonal coupler 2.

[0035] The orthogonal coupler 1 can receive a single-ended RF input and output two orthogonal RF signals. For example, the orthogonal coupler 1 can output the two orthogonal RF signals to a first balanced amplifier module and a second balanced amplifier module, respectively. The orthogonal coupler 1 may include: an input transformer T1, an input capacitor C1, and an input resistor R1. The transformer T1 includes a first winding ( Figure 3 The upper winding of transformer T1) and the second winding ( Figure 3 The first winding can be connected between the single-ended RF input and the input of the first balanced amplifier module. Capacitor C11 can be connected between the single-ended RF input and the input of the second balanced amplifier module. One end of the second winding is connected between input capacitor C1 and the input of the second balanced amplifier module, and the other end of the second winding is grounded through input resistor R1. By implementing the orthogonal coupler 1 in a transformer manner, the chip area occupied can be reduced and integration is facilitated. In addition, the orthogonal coupler 1 has a wide frequency range and can output orthogonal signals throughout the n41 and n77 frequency bands.

[0036] The first balanced amplification module can receive one orthogonal RF signal from the first orthogonal coupler, amplify the one orthogonal RF signal, and output a first amplified signal. For example, the first balanced amplification module can output the first amplified signal to orthogonal coupler 2. The second balanced amplification module can receive another orthogonal RF signal from the first orthogonal coupler, amplify the other orthogonal RF signal, and output a second amplified signal. For example, the second balanced amplification module can output the second amplified signal to orthogonal coupler 2.

[0037] Quadrature coupler 2 receives the first and second amplified signals in quadrature and generates a single-ended RF output. The output port of quadrature coupler 2 can be grounded via output resistor R2. By combining the output power of the first and second balanced amplifier modules, quadrature coupler 2 can output higher power across the entire n41 and n77 frequency bands. The first and second balanced amplifier modules can be implemented using conventional single-ended Class-AB amplifiers.

[0038] although Figure 3 Not shown, but Figure 3 The radio frequency power amplifier circuit may further include a control unit, which may be configured to control the bias state of each stage of the amplifier and the on state of the switch module.

[0039] The technical solution of the utility model has a compact structure, is easy to integrate, and occupies a small volume; in addition, it has a wide output bandwidth and high output power, and is suitable for use in mobile terminal equipment.

[0040] Figure 4 Schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model.

[0041] refer to Figure 4 According to an embodiment of the present invention, the radio frequency power amplifier circuit includes an orthogonal coupler 1, a first balanced amplifier module, a second balanced amplifier module, and an orthogonal coupler 2.

[0042] The first balanced amplification module includes an input matching network 1, an amplifier 1, and an output matching network 1; the second balanced amplification module includes an input matching network 2, an amplifier 2, and an output matching network 2.

[0043] In one embodiment, one or more of the input matching network 1, the output matching network 1, the input matching network 2, and the output matching network 2 include a matching transformer. The matching transformer can be used to adjust voltage and impedance.

[0044] In one embodiment, one or more of the input matching network 1, the output matching network 1, the input matching network 2, and the output matching network 2 include an LC network. The LC network can be used to adjust the impedance.

[0045] Amplifier 1 and amplifier 2 may be formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor. Amplifier 1 and amplifier 2 may be implemented by a conventional single-ended Class-AB amplifier.

[0046] The orthogonal coupler 2 can receive the first amplified signal and the second amplified signal in quadrature and generate a single-ended RF output. The orthogonal coupler 2 may include: an output transformer T2, an output resistor R2. The output transformer T2 may include a third winding (e.g., Figure 4 The lower winding of the transformer T2 in FIG) and the fourth winding (eg, Figure 4 (The upper winding of transformer T2 in FIG. 1 ). One end of the third winding can be connected to the single-ended RF output, and the other end of the third winding can be connected to the second balanced amplifier module. For example, the other end of the third winding can be connected to output matching network 2 of the second balanced amplifier module. One end of the fourth winding can be connected to the first balanced amplifier module, and the other end of the fourth winding can be grounded via output resistor R2. For example, one end of the fourth winding can be connected to output matching network 1 of the first balanced amplifier module.

[0047] By combining the output powers of the first balanced amplifying module and the second balanced amplifying module, the orthogonal coupler 2 can output higher power in the entire n41 and n77 frequency bands.

[0048] although Figure 4 Not shown, but Figure 4 The radio frequency power amplifier circuit may further include a control unit, which may be configured to control the bias state of each stage of the amplifier and the on state of the switch module.

[0049] Figure 5 Schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present utility model.

[0050] Figure 5 Zhongyu Figure 4 The same components will not be described again. Figure 5 The RF power amplifier circuit also includes a filter and a switch module to meet out-of-band suppression and multi-antenna transmission application scenarios. The filter and switch module can be connected between one end of the third winding and the single-ended RF output. The filter and switch module can be connected in series. The filter can filter the signal output by the orthogonal coupler 2. The switch module can be configured to switch between different antenna ports.

[0051] Figures 6A-6C is a schematic diagram showing an implementation of the transformer T1 in the orthogonal coupler 1 according to an embodiment of the present invention. Figures 7A-7C is a schematic diagram showing an implementation of the transformer T2 in the orthogonal coupler 2 according to an embodiment of the present invention.

[0052] Figure 6A As shown, the transformer T1 of the orthogonal coupler 1 can be formed by a rectangular pattern of a two-layer metal structure. The transformer T1 used in the orthogonal coupler 1 can be implemented on a GaAs wafer by two layers of metal. Figure 6A The RF input in the RF amplifier module can be connected to the single-ended RF input, and a capacitor C1 can be connected between the RF input and the RF output (for example, RF output 1). The input end of the first balanced amplifier module can be connected to Figure 6A The input of the second balanced amplifier module can be connected to the RF output 1. The isolated port can be grounded through the resistor R1. Figure 6B and Figure 6C As shown, the first and second metal layers may include rectangular patterns to form transformer T1.

[0053] like Figure 7A As shown, the transformer T2 in the orthogonal coupler 2 can be formed by a pattern of a three-layer metal structure. The isolation port can be grounded through the output resistor R2. The two RF inputs can be connected to the first balanced amplifier module and the second balanced amplifier module respectively. Figure 7B As shown, the first metal layer may include a rectangular pattern. Figure 7C As shown, the second metal layer may include rectangular patterns, and the third metal layer may include patterns formed by connecting the rectangular patterns in the second metal layer at the connection region.

[0054] Figure 8 1 is a phase-frequency diagram showing the orthogonal coupler 1 according to an embodiment of the present invention. Figure 8 , it can be seen that across the entire frequency range of the n41 and n77 bands, two outputs with a phase difference of substantially 90° can be achieved. Therefore, the Doherty RF power amplifier according to an embodiment of the present invention can be applied to 5G communication systems, and in particular, can be applied to the entire frequency range of the n41 and n77 bands within the 5G communication band.

[0055] Figure 9 3 is a schematic diagram showing an example implementation of a matching network for a radio frequency power amplifier circuit according to an embodiment of the present invention.

[0056] refer to Figure 9 In order to reduce the area and cost of the entire module, the inductors in the matching networks (e.g., input matching network 1, input matching network 2, output matching network 1, output matching network 2) can be implemented by a combination of bonding wires and substrate microstrip lines.

[0057] Figure 10 is a plan view showing a multi-chip package of a Doherty RF power amplifier according to an embodiment of the present invention, and Figure 11 FIG. 1 is a side view showing a multi-chip package of a Doherty radio frequency power amplifier according to an embodiment of the present invention.

[0058] Multi-Chip Module Doherty structure power amplifiers are gradually used in mobile terminals. Figure 10 and Figure 11 , multiple chips (e.g., controller, power amplifier, low noise amplifier, switch module, output balun / transformer module) are integrated into a module through a multi-layer substrate, and multiple chips can be interconnected through bonding wires. For example, refer to Figure 10 The power amplifier chip and the output balun module are interconnected by bonding wires. By adopting a multi-chip integrated module structure, the radio frequency power amplifier circuit according to the embodiment of the utility model can be further applied to mobile terminals.

[0059] Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.

[0060] Any description in this utility model should not be construed as implying that any particular element, step, or function is an essential element that must be included in the scope of the claims. The scope of the patented subject matter is limited only by the claims.

Claims

1. A radio frequency power amplifier circuit, characterized in that: include: a first orthogonal coupler configured to receive a single-ended radio frequency input and output two orthogonal radio frequency signals; a first balanced amplifying module configured to receive one channel of orthogonal radio frequency signals from the first orthogonal coupler, amplify the one channel of orthogonal radio frequency signals and output a first amplified signal; a second balanced amplifying module configured to receive the other orthogonal RF signal from the first orthogonal coupler, amplify the other orthogonal RF signal and output a second amplified signal; a second quadrature coupler configured to receive the first amplified signal and the second amplified signal in quadrature and generate a single-ended radio frequency output; The first orthogonal coupler includes: an input transformer including a first winding and a second winding, an input capacitor, and an input resistor, wherein: The first winding is connected between the single-ended RF input and the input of the first balanced amplifier module. The input capacitor is connected between the single-ended RF input and the input of the second balanced amplification module. One end of the second winding is connected between the input capacitor and the input end of the second balanced amplification module, and the other end of the second winding is grounded through an input resistor.

2. The radio frequency power amplifier circuit according to claim 1, wherein: The second orthogonal coupler includes: an output transformer including a third winding and a fourth winding, and an output resistor, wherein: One end of the third winding is connected to the single-ended RF output, and the other end of the third winding is connected to the second balanced amplifier module. One end of the fourth winding is connected to the first balanced amplifying module, and the other end of the fourth winding is grounded through an output resistor.

3. The radio frequency power amplifier circuit according to claim 1, wherein: The first balanced amplification module includes a first input matching network, a first amplifier, a first output matching network, and The second balanced amplification module includes a second input matching network, a second amplifier, and a second output matching network.

4. The radio frequency power amplifier circuit according to claim 1, wherein: One or more of the first input matching network, the first output matching network, the second input matching network, and the second output matching network include a matching transformer.

5. The radio frequency power amplifier circuit according to claim 1, wherein: One or more of the first input matching network, the first output matching network, the second input matching network, and the second output matching network include an LC network.

6. The radio frequency power amplifier circuit according to claim 3, characterized in that: The first amplifier and the second amplifier are formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor.

7. The radio frequency power amplifier circuit according to claim 2, characterized in that: It also includes a filter and a switch module connected between the one end of the third winding and the single-ended RF output, wherein the filter and the switch module are connected in series.

8. The radio frequency power amplifier circuit according to claim 1, wherein: The input transformer is formed by a rectangular pattern of two-layer metal structures.

9. The radio frequency power amplifier circuit according to claim 2, characterized in that: The output transformer is formed by a pattern of a three-layer metal structure.

10. The radio frequency power amplifier circuit according to claim 5, characterized in that: The inductor in the LC network is formed by a combination of bond wires and substrate microstrip lines.

11. The radio frequency power amplifier circuit according to claim 1, wherein: The radio frequency power amplifier circuit is packaged through a multi-layer substrate package for multiple chips.

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