Radio frequency power amplifier module, control method and power amplifier

Abstract

The invention discloses a radio frequency power amplifier module, a control method and a power amplifier, and the module comprises a power amplifier chip which outputs power to an antenna unit through a transformer power synthesis network; wherein the output power of the radio frequency power amplifier module is in positive correlation with the number of the power amplifier chips. A transformer power synthesis network is adopted, so that the module can integrate one or a plurality of same power amplifier chips, different output power levels are flexibly configured, the design and mass production of chips of various sizes for different power requirements are avoided, and the research and development investment is reduced. Besides, due to the adoption of a power synthesis method, on the premise that the power supply voltage is not changed, the optimal load impedances corresponding to different numbers of chips are kept consistent, the design of a matching network is simplified, and the problems that in the traditional high-power chip design, the passive loss is increased and the power improvement is limited due to the fact that the chip size is increased are effectively avoided. And the design flexibility and performance of the high-power amplifier are improved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency power amplifier design technology, and in particular to a radio frequency power amplifier module, control method and power amplifier. Background Technology

[0002] According to microwave theory, the coverage distance of wireless communication is positively correlated with the wireless transmission power, and the radio frequency power amplifier (PA) is the core component that determines the transmission power. Theoretically, the communication distance doubles for every 3dBm increase in power. However, in practical applications, different communication scenarios have different requirements for coverage distance, thus necessitating PAs with different power levels. The traditional solution is to design a separate, fixed-power PA chip for each power requirement. For example, to meet power requirements of 1W, 2W, and 4W, three separate R&D, design, and tape-out processes are required, resulting in long development cycles and high costs.

[0003] Please refer to Figure 1 The traditional approach is to design PA chips with different power ratings to meet different power requirements. However, since power P = V... 2 Under the premise of constant power supply voltage, the load impedance required to realize chips with different power ratings is different. From left to right, there are three power amplifiers with power ratings of 1W, 2W, and 4W. Theoretically, their required load impedance relationship is RL. 1w =2*RL 2w =4*RL 4w Meanwhile, in order to provide sufficient power, the size of the power amplifier must also be increased accordingly. The size generally follows the relationship with the power, that is, 1:2:4. However, in actual implementation, the implementation of high power amplifiers becomes more difficult. On the one hand, lower load impedance often leads to greater passive matching loss. On the other hand, a larger chip size often fails to increase power due to parasitic effects. That is, the area increases but the power does not increase. This is more common in high-frequency, high-power amplifiers because the parasitic effect is more severe at higher frequencies. Summary of the Invention

[0004] The purpose of this invention is to provide an RF power amplifier module, a control method, and a power amplifier, which reduces the passive loss and manufacturing cost of the chip and increases the RF power of the chip.

[0005] This invention discloses a radio frequency power amplifier module, comprising:

[0006] The power amplifier chip outputs power to the antenna unit through a transformer power combining network;

[0007] The output power of the radio frequency power amplifier module is positively correlated with the number of power amplifier chips.

[0008] Furthermore, the transformer power combining network includes: a power combining transformer;

[0009] The primary winding of the power combining transformer is connected to the output terminal of the power amplifier chip, and the secondary winding is connected to the input terminal of the antenna unit.

[0010] Furthermore, it also includes an output matching network;

[0011] The secondary winding of the power combining transformer is connected to the input terminal of the antenna unit through an output matching network.

[0012] Furthermore, the input terminal of the antenna unit is connected to the output terminal of the output matching network.

[0013] Furthermore, the power amplifier chip is a differential power amplifier chip.

[0014] Furthermore, the power amplifier chip includes:

[0015] A driver amplifier is used to receive radio frequency input signals;

[0016] Interstage matching balun, used to convert the single-ended RF input signal into a differential signal;

[0017] A differential power amplifier is used to amplify the differential signal and input the differential signal to the transformer power combining network.

[0018] Furthermore, the power amplifier chip is manufactured using HBT or CMOS technology.

[0019] Furthermore, it also includes an input matching network and a matching capacitor;

[0020] The input matching network is connected to the input terminal of the power amplifier chip via the matching capacitor.

[0021] On the other hand, the present invention also discloses a method for controlling an RF power amplifier module, which uses the above-mentioned RF power amplifier module for control.

[0022] On the other hand, the present invention also discloses a radio frequency power amplifier, including the radio frequency power amplifier module described above.

[0023] Compared with the prior art, the present invention has at least the following technical effects:

[0024] This invention employs a transformer power combining network, enabling the integration of one or more identical power amplifier chips into a module. This allows for flexible configuration of different output power levels, eliminating the need to design and mass-produce chips of various sizes to meet different power requirements, significantly reducing R&D investment, manufacturing costs, and inventory expenses. Furthermore, due to the power combining method, the optimal load impedance remains consistent across different numbers of chips while maintaining a constant power supply voltage. This simplifies the design of the matching network and effectively avoids the increased passive losses and power limitations caused by larger chip sizes in traditional high-power chip designs, thereby enhancing the flexibility and performance of high-power amplifier designs. Attached Figure Description

[0025] Figure 1 This is a simplified schematic diagram of the structure of a radio frequency power amplifier module in the prior art;

[0026] Figure 2 This is a simplified schematic diagram of the radio frequency power amplifier module structure in Embodiment 1 of the present invention;

[0027] Figure 3 This is a simplified schematic diagram of another structure of the radio frequency power amplifier module in Embodiment 1 of the present invention;

[0028] Figure 4 This is a simplified schematic diagram of another structure of the radio frequency power amplifier module in Embodiment 1 of the present invention. Detailed Implementation

[0029] The following detailed description, with reference to schematic diagrams, outlines a radio frequency power amplifier module, control method, and power amplifier according to the present invention, illustrating preferred embodiments of the invention. It should be noted that the following description is intended to enable those skilled in the art to understand and implement the invention, and is for illustrative purposes only, not for limiting the scope of the invention. Those skilled in the art should understand that, based on the teachings of this specification, various modifications, equivalent substitutions, or improvements can be made to the described specific embodiments without departing from the core spirit and principles of the invention. For example, technical features from different embodiments can be cross-combined to form new technical solutions. As long as no technical contradictions arise, these variations and combinations should fall within the scope of protection claimed by the present invention.

[0030] The invention is described more specifically by way of example in the following paragraphs with reference to the accompanying drawings. The advantages and features of the invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the invention.

[0031] Example 1

[0032] Please refer to Figures 2-4This embodiment discloses a radio frequency power amplifier module, including:

[0033] The power amplifier chip (PA Chip in the diagram) outputs power to the antenna unit 2 through the transformer power combining network 1;

[0034] The output power of the radio frequency power amplifier module is positively correlated with the number of power amplifier chips.

[0035] In this embodiment, by employing a transformer power combining network 1, the module can flexibly integrate one or more identical power amplifier chips, thereby easily configuring different output power levels. This avoids the hassle of designing and mass-producing chips of various sizes for different power requirements, significantly reducing R&D investment, manufacturing costs, and inventory expenses, and greatly improving the flexibility and overall performance of high-power amplifier design. Furthermore, using the transformer power combining network 1 for power combining ensures that the optimal load impedance remains consistent even with a constant power supply voltage, simplifying the design of the matching network and effectively avoiding the technical bottlenecks of increased passive losses and limited power output caused by increased size in traditional high-power chip designs.

[0036] Specifically, in terms of impedance matching, each unit power amplifier chip in this architecture only needs to be matched to its own optimal load impedance point. This impedance value is relatively high, making it easy to implement a high-efficiency on-chip matching network. Subsequently, the transformer power combining network 1 transforms and combines the n matched high impedances, ultimately presenting a standard 50-ohm system impedance to the external load (such as antenna unit 2). This method fundamentally avoids the technical bottlenecks of complex matching network design and increased losses caused by the extremely low load impedance (e.g., less than 1 ohm) that traditional monolithic high-power solutions must deal with in order to obtain high power.

[0037] In terms of parasitic effect suppression, this architecture uses standardized, small-sized unit power amplifier chips as the basic building blocks. Compared to monolithically integrated large-size transistors, the inherent parasitic parameters (such as parasitic capacitance and inductance) of these unit chips are significantly reduced, thus ensuring their excellent high-frequency characteristics and operating bandwidth. By combining multiple such high-performance unit chips through a power combining strategy to increase the total power, this effectively avoids the technical problem in traditional solutions where the large size of active devices leads to a sharp deterioration of parasitic effects, thereby limiting the maximum output power and frequency response.

[0038] In one specific example, the RF power amplifier module includes three identical power amplifier chips, thereby forming a low, medium and high frequency power amplifier module to achieve a power output of 2W.

[0039] For another specific example, please refer to Figure 3The radio frequency power amplifier module includes four identical power amplifier chips (PA Chip1, PA Chip2P, PA Chip3 and PA Chip4), thereby forming a high-frequency power amplifier module to achieve a power output of 4W.

[0040] In another specific example, the RF power amplifier module includes a power amplifier chip, thereby constituting a low-power amplifier module to achieve a power output of 1W.

[0041] Please refer to Figure 3 and Figure 4 ,Depend on Figure 3 and Figure 4 It is evident that the number of power amplifier chips in the aforementioned RF power amplifier module is not limited to 1, 3, or 4. Those skilled in the art can select different numbers of power amplifier chips according to actual circumstances, such as 2, 5, or more, without making specific restrictions here.

[0042] Furthermore, the transformer power combining network 1 includes a power combining transformer.

[0043] Specifically, the primary winding of the power combining transformer is connected to the output terminal of the power amplifier chip, and the secondary winding is connected to the input terminal of the antenna unit 2.

[0044] In a specific example, the power combining transformer can be manufactured using Low-Temperature Co-fired Ceramic (LTCC) technology. Specifically, the primary and secondary windings of the transformer are not traditional wire-wound coils, but rather, through screen printing, highly conductive metal paste (such as silver paste) is printed in optimized spiral or interlaced structures onto different layers of multiple green ceramic films. These films are then precisely stacked, laminated, and sintered together to form a robust and highly integrated single component with a complex three-dimensional winding embedded within. This LTCC-based transformer not only achieves extremely small physical dimensions but also achieves excellent magnetic field coupling and extremely low insertion loss due to its three-dimensional winding structure. It can be used as a high-performance passive device, directly mounted on a circuit board or integrated into an RF front-end module, efficiently performing impedance matching and power combining functions between one or more power amplifier chips and antenna unit 2.

[0045] Furthermore, the RF power amplifier module also includes an output matching network (illustrated as Output Match).

[0046] Specifically, the secondary winding of the power combining transformer is connected to the input terminal of the antenna unit 2 through an output matching network.

[0047] In one specific example, the output matching network can be implemented using an LC network (a filter network composed of capacitors and inductors) or a transmission line transformer to adjust the impedance after power combining to match the input impedance of antenna element 2. Of course, those skilled in the art can choose different types of output matching networks according to actual conditions, and no specific limitations are made here.

[0048] In this embodiment, the radio frequency (RF) signal output from the power amplifier chip is multiplied by a power combining transformer. The primary winding is directly connected to the chip output to reduce transmission loss, while the secondary winding is connected to the RF output after impedance adjustment by an output matching network. During power combining, the primary winding receives parallel signals from multiple power amplifier chips, achieving power superposition through electromagnetic induction. The output matching network adjusts the inductor and capacitor parameters to match the impedance of the combined signal with the RF output, thereby improving energy transmission efficiency.

[0049] Through the above technical solution, the present invention achieves efficient synthesis and impedance matching of output signals of multi-channel power amplifier chips, and solves the impedance mismatch problem in high-frequency power synthesis while maintaining chip miniaturization, effectively improving the output efficiency and stability of RF power amplifiers.

[0050] Furthermore, the input terminal of the antenna unit 2 is connected to the output terminal of the output matching network.

[0051] In a specific example, antenna element 2 refers to a radiating structure used to receive or transmit electromagnetic waves. Specifically, it can be implemented using a microstrip patch antenna or a dipole antenna, and its input end is connected to the radio frequency front-end circuit through a transmission line.

[0052] Furthermore, the power amplifier chip is a differential power amplifier chip.

[0053] In one specific example, the power amplifier chip includes: a driver amplifier (illustrated as PAD+) for receiving a radio frequency input signal; an interstage matching balun for converting the single-ended radio frequency input signal into a differential signal; and differential power amplifiers (illustrated as PA+ and PA-) for amplifying the differential signal and inputting the differential signal to the transformer power combining network 1.

[0054] The specific connection method of each component in the power amplifier is as follows: the input terminal of the driver amplifier receives the radio frequency input signal through the first matching capacitor C1, the output terminal of the driver amplifier is connected to the first input terminal of the interstage matching balun, the second input terminal of the interstage matching balun is grounded through the second matching capacitor C2 and connected to the power supply voltage VDD_PAD, the output terminal of the interstage matching balun is connected to the signal input terminal of the differential power amplifier, and the signal output terminal of the differential amplifier is connected to the antenna unit 2 through the transformer power combining network 1.

[0055] Specifically, the radio frequency (RF) signal output from the power amplifier chip is multiplied by a power combining transformer. The primary winding is directly connected to the chip output to reduce transmission loss, while the secondary winding is connected to the RF output after impedance adjustment by an output matching network. During power combining, the primary winding receives parallel signals from multiple power amplifier chips, achieving power superposition through electromagnetic induction. The output matching network adjusts the inductor and capacitor parameters to match the impedance of the combined signal with the RF output, thereby improving energy transmission efficiency.

[0056] Through the above technical solutions, this application can effectively suppress power loss caused by high-frequency parasitic effects, improve the efficiency of impedance matching networks, and enhance the linearity of RF signals during power combining. The anti-interference characteristics of the differential structure also reduce the impact of external electromagnetic noise on amplifier performance, resulting in higher output stability of the RF power amplifier module in high-frequency communication scenarios.

[0057] Furthermore, the power amplifier chip is manufactured using HBT or CMOS technology.

[0058] HBT (Heterojunction Bipolar Transistor) technology, specifically implemented using compound semiconductor materials such as gallium arsenide or indium phosphide, offers high carrier mobility and high breakdown voltage, making it suitable for high-frequency, high-power applications. CMOS (Complementary Metal-Oxide-Semiconductor) technology, specifically implemented using silicon-based semiconductor materials, offers high integration density and low power consumption, making it suitable for large-scale integrated circuit manufacturing. Those skilled in the art can choose different processes for power amplifier fabrication based on specific needs.

[0059] Furthermore, it also includes an input matching network and a matching capacitor. The input matching network is connected to the input terminal of the power amplifier chip through the matching capacitor.

[0060] The input matching network refers to the circuit structure used to achieve impedance matching between the RF signal input terminal and the power amplifier chip. It can be implemented using microstrip lines, lumped inductors, or combinations of capacitors. Its function is to adjust the real and imaginary parts of the input impedance so that the RF signal can be transmitted to the power amplifier chip with minimal reflection loss. The matching capacitor refers to the capacitor element used to block DC components and adjust the input impedance matching characteristics. It can be implemented using metal-insulator-metal structure capacitors or variable capacitors. Its function is to adjust the impedance characteristics of the input circuit through capacitive reactance, suppressing the influence of high-frequency parasitic parameters on input matching.

[0061] Specifically, the input matching network forms a series structure with the input terminal of the power amplifier chip through a matching capacitor. When the RF input signal enters the input matching network, its impedance characteristics are adjusted to be conjugate matched with the input impedance of the power amplifier chip. During this process, the matching capacitor blocks the influence of DC bias voltage on the preceding circuitry and simultaneously forms a resonant circuit with the inductor or transmission line in the input matching network, offsetting the high-frequency impedance shift caused by the parasitic capacitance at the input terminal of the power amplifier chip. Therefore, the reflection loss of the RF signal at the input terminal is reduced, and the power transmission efficiency is improved.

[0062] Furthermore, this embodiment also discloses a method for controlling an RF power amplifier module, which uses the aforementioned RF power amplifier module for control.

[0063] Specifically, the control method dynamically adjusts the output power level by regulating the number of power amplifier chips activated in the RF power amplifier module. When increased communication distance is required, more chips are activated and their output power is amplified through the transformer power combining network 1; when reduced power consumption is required, the number of activated chips is reduced. The output matching network automatically adjusts the impedance matching parameters based on the currently activated number of chips to ensure power transmission efficiency.

[0064] In a specific example, the power supply status of different power amplifier chips can be controlled via a switching circuit. For instance, only a single chip can be activated in low-power mode, while all four chips can be activated simultaneously in high-power mode. The parameters of the matching capacitors and input matching networks can be dynamically configured according to the number of chips activated, for example, by using an adjustable capacitor array to achieve real-time input impedance matching.

[0065] Through the above technical solution, this application can flexibly adjust the output power according to the actual communication scenario, avoiding the repeated development of dedicated chips for different power requirements, significantly shortening the development cycle and reducing manufacturing costs. The linear expansion characteristic of the number of power amplifier chips effectively solves the impedance matching problem in high-frequency and high-power scenarios, while suppressing the impact of parasitic parameters on performance.

[0066] Furthermore, this embodiment discloses a radio frequency power amplifier, including the radio frequency power amplifier module described above.

[0067] In this design, the outputs of multiple power amplifier chips are connected to the primary winding of a power combining transformer, and the secondary winding is impedance matched to antenna unit 2 via an output matching network. When an increase in output power is required, the number of power amplifier chips connected in parallel is increased to keep the equivalent load impedance of the combining network within a matchable range, avoiding matching losses caused by excessively low load impedance of a single chip. Simultaneously, the chips employ a distributed layout to effectively suppress the impact of high-frequency parasitic parameters on overall performance.

[0068] Through the above technical solution, this application can flexibly configure the output power level according to the actual application scenario, and achieve linear power expansion while maintaining chip process consistency. This effectively solves the impedance matching difficulties and parasitic effect limitations faced by high-frequency, high-power amplifiers in traditional solutions. At the same time, the modular structure reduces the development difficulty of products with different power levels and enables the reuse of R&D resources.

[0069] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A radio frequency power amplifier module, characterized in that, include: The power amplifier chip outputs power to the antenna unit through a transformer power combining network; The output power of the radio frequency power amplifier module is positively correlated with the number of power amplifier chips.

2. The RF power amplifier module as described in claim 1, characterized in that, The transformer power combining network includes: a power combining transformer; The primary winding of the power combining transformer is connected to the output terminal of the power amplifier chip, and the secondary winding is connected to the input terminal of the antenna unit.

3. The RF power amplifier module as described in claim 2, characterized in that, It also includes the output matching network; The secondary winding of the power combining transformer is connected to the input terminal of the antenna unit through an output matching network.

4. The RF power amplifier module as described in claim 3, characterized in that, The input terminal of the antenna element is connected to the output terminal of the output matching network.

5. The RF power amplifier module as described in claim 4, characterized in that, The power amplifier chip is a differential power amplifier chip.

6. The RF power amplifier module as described in claim 5, characterized in that, The power amplifier chip includes: A driver amplifier used to receive radio frequency input signals; Interstage matching balun, used to convert the single-ended RF input signal into a differential signal; A differential power amplifier is used to amplify the differential signal and input the differential signal to the transformer power combining network.

7. The RF power amplifier module as described in claim 5, characterized in that, The power amplifier chip is manufactured using HBT or CMOS technology.

8. The RF power amplifier module as described in claim 5, characterized in that, It also includes an input matching network and a matching capacitor; The input matching network is connected to the input terminal of the power amplifier chip via the matching capacitor.

9. A method for controlling an RF power amplifier module, characterized in that, The control is performed using the RF power amplifier module as described in any one of claims 1-8.

10. A radio frequency power amplifier, characterized in that, Includes the radio frequency power amplifier module as described in any one of claims 1-8.

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