Multi-band radio frequency transceiver circuit, multi-band radio frequency transceiver module and terminal equipment

Abstract

The invention provides a multi-band radio frequency transceiver circuit, a multi-band radio frequency transceiver module and terminal equipment, and the multi-band radio frequency transceiver circuit comprises a baseband chip, a radio frequency integrated circuit module, a power amplifier switch integrated module, a high-frequency receiving filter, a low-frequency receiving filter and an antenna module. Wherein the baseband chip is used for processing a baseband signal, the radio frequency integrated circuit module is used for amplifying a transmitting signal or demodulating a receiving signal, the power amplifier switch integrated module is used for amplifying the transmitting signal and guiding high and low frequency receiving signals, and the high and low frequency receiving filter is used for purifying the signals. And the antenna module is used for completing signal emission and multi-band mixed signal acquisition. Therefore, the circuit can realize efficient transceiving of multi-band signals, interference is effectively reduced through filtering purification, and the signal-to-noise ratio of received signals is improved; the processing link is optimized in a modularized division mode, the signal transmission stability is enhanced, the communication quality is guaranteed, and the multi-scene communication requirement is met.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a multi-band radio frequency transceiver circuit, a multi-band radio frequency transceiver module, and a terminal device. Background Technology

[0002] With the globalization of the mobile communication industry, radio frequency circuits need to adapt to the needs of domestic and overseas communication frequency bands. Developing a universal radio frequency circuit board that is compatible with multiple frequency bands has become the preferred solution to avoid frequency band confusion in later shipments. At present, there are various types of multi-band radio frequency circuit solutions on the market, and each solution has its own characteristics in hardware architecture design.

[0003] However, the core functional modules of existing multi-band RF circuits mostly adopt a discrete design architecture. The modules require additional configuration of supporting circuits and traces, which not only places high demands on the design standards of printed circuit boards and is prone to signal stability issues, but also increases the difficulty of procurement management and cost due to the large variety and quantity of required components, which may lead to a longer product delivery cycle. At the same time, the frequency band adaptation-related components at the receiver end adopt an independent configuration mode, which further compresses the layout margin of the printed circuit board and significantly restricts the compact design of the overall circuit. Summary of the Invention

[0004] This application proposes a multi-band RF transceiver circuit, a multi-band RF transceiver module, and a terminal device, aiming to achieve multi-channel signal transmission and reception capabilities, adapt to multi-band signal processing, and enhance communication compatibility in various scenarios. Furthermore, by coordinating frequency band gating and filtering purification, out-of-band interference is reduced, ensuring the signal-to-noise ratio of the received signal and communication stability. Additionally, by replacing traditional discrete components with an integrated design, the circuit procurement cost and printed circuit board (PCB) layout space occupancy are significantly reduced.

[0005] In a first aspect, embodiments of this application provide a multi-band radio frequency transceiver circuit, including: a baseband chip, a radio frequency integrated circuit module, a power amplifier switch integrated module, a high-frequency receiving filter, a low-frequency receiving filter, and an antenna module; The baseband chip is connected to the first port of the RF integrated circuit module, the second port of the RF integrated circuit module is connected to the first port of the power amplifier switch integrated module, the second port of the power amplifier switch integrated module is connected to the antenna module, the third port of the power amplifier switch integrated module is connected to the first port of the high-frequency receiving filter, the fourth port of the power amplifier switch integrated module is connected to the first port of the low-frequency receiving filter, the second port of the low-frequency receiving filter is connected to the third port of the RF integrated circuit module, and the second port of the high-frequency receiving filter is connected to the fourth port of the RF integrated circuit module. The baseband chip is used to generate and transmit baseband signals to the radio frequency integrated circuit module; or, to receive the demodulated baseband signals output by the radio frequency integrated circuit module and convert the demodulated baseband signals into analog signals. The radio frequency integrated circuit module is used to modulate the transmit baseband signal onto the transmit carrier and perform signal power amplification to output the target transmit signal to the power amplifier switch integrated module; or, to receive the target receive signal purified by a high-frequency receive filter or a low-frequency receive filter, and to obtain and output the demodulated baseband signal to the baseband chip after amplifying and demodulating the target receive signal. The power amplifier switch integrated module is used to amplify the target transmitted signal and transmit the processed target transmitted signal to the antenna module; or, to receive the multi-band mixed signal collected by the antenna module, and to guide the high-frequency received signal in the multi-band mixed signal to the high-frequency receiving filter, or to guide the low-frequency received signal in the multi-band mixed signal to the low-frequency receiving filter. A high-frequency receiving filter is used to filter and purify the high-frequency received signal to obtain the purified target received signal, and to transmit the target received signal to the radio frequency integrated circuit module. The low-frequency receiving filter is used to filter and purify the low-frequency received signal to obtain the purified target received signal, and to transmit the target received signal to the radio frequency integrated circuit module. The antenna module is used to receive the processed target transmission signal output by the power amplifier switch integrated module and transmit it to complete the signal transmission operation; or, it can collect multi-band mixed signals and transmit the multi-band mixed signals to the power amplifier switch integrated module to complete the signal reception operation.

[0006] Secondly, embodiments of this application provide a multi-band radio frequency transceiver module, including the multi-band radio frequency transceiver circuit as described in the first aspect.

[0007] Thirdly, embodiments of this application provide a terminal device, including a multi-band radio frequency transceiver module as described in the second aspect.

[0008] In this application embodiment, the multi-band compatible RF circuit, through the integrated architecture design of power amplifier and switching circuits, the optimized configuration of receiver devices, and the integrated design strategy of impedance matching and routing, can solve the problems of limited layout space and high signal interference risk caused by existing discrete designs, while achieving the universal RF circuit public board design requirements that accommodate domestic and international communication frequency bands. Furthermore, compared to traditional discrete power amplifier and switching circuits and independent receiver filters, the multi-band compatible RF circuit provided in this application significantly reduces hardware procurement costs and PCB layout difficulty, while significantly improving signal transmission stability and effectively shortening product development and delivery cycles. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the structure of a multi-band radio frequency transceiver circuit provided in an embodiment of this application; Figure 2 This is a schematic diagram of another multi-band radio frequency transceiver circuit provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a power amplifier switch switching circuit provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a radio frequency transceiver circuit provided in an embodiment of this application. Detailed Implementation

[0011] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0012] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0013] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0014] In the embodiments of this application, "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone; A and B exist simultaneously; B exists alone. Among them, A and B can be singular or plural.

[0015] In this embodiment, the symbol " / " can indicate that the preceding and following objects are in an "or" relationship. Alternatively, the symbol " / " can also represent a division sign, i.e., performing a division operation. For example, A / B can mean A divided by B.

[0016] In the embodiments of this application, "at least one item" or its similar expression refers to any combination of these items, including any combination of a single item or a plurality of items. "One or more" means one or more, while "multiple" means two or more. For example, "at least one item" of a, b, or c can represent the following seven cases: a, b, c; a and b; a and c; b and c; a, b, and c. Each of a, b, and c can be an element or a set containing one or more elements.

[0017] In the embodiments of this application, "equal to" can be used with "greater than" and is applicable to technical solutions used when "greater than" is used; it can also be used with "less than" and is applicable to technical solutions used when "less than" is used. When "equal to" is used with "greater than", it is not used with "less than"; when "equal to" is used with "less than", it is not used with "greater than".

[0018] To better understand the solutions of the embodiments of this application, the terminal devices, related concepts and background that may be involved in the embodiments of this application will be introduced below.

[0019] 1. RX SAW: Receive Surface Acoustic Wave Filter, a core passive device in the RX circuit, utilizes the surface acoustic wave principle to filter and purify the received radio frequency signal, removing out-of-band interference and outputting a clean received signal in the target frequency band. The high-frequency and low-frequency receiving filters mentioned in this application both belong to this RX SAW. They are dedicated receiving filter devices classified according to the characteristics of the corresponding communication frequency bands. Both types of filters are based on the surface acoustic wave filtering principle, filtering and purifying the high-frequency and low-frequency radio frequency signals in the receiving path respectively, removing out-of-band interference, and outputting a clean received signal in the target frequency band, which is then transmitted to the radio frequency integrated circuit for subsequent demodulation processing.

[0020] 2. Radio Frequency IC: The full English name is Radio Frequency Integrated Circuit, which is the core control and signal processing module of a radio frequency (RF) circuit. It performs key functions such as modulation, demodulation, amplification, and frequency conversion of RF signals, connects the receiving and transmitting lines, and completes the core logic processing for signal transmission and reception. The RF integrated circuit module mentioned in this application belongs to this RF IC and performs the same functions.

[0021] 3. PCB LAYOUT: The English translation is printed circuit board layout and routing. It refers to the process of planning the physical placement of components on the PCB substrate, designing the routing of conductive lines, and completing key processes such as impedance matching and ground plane design according to the circuit design requirements. It directly determines the signal stability, anti-interference ability and space utilization of the circuit.

[0022] 4. TXIQ: The full English name is Transmit In-phase / Quadrature Signal, which is the baseband signal form of the RF transmitter. It is generated by the baseband chip, transmitted to the RF IC, and then modulated and converted into a transmittable RF signal. The specific signal form of the transmit baseband signal mentioned in this application is TXIQ. This baseband signal is generated by the baseband chip and is the core baseband signal carrier of the RF transmission link. After the transmit baseband signal is transmitted to the RF integrated circuit, it is modulated and amplified to be converted into a transmittable RF signal to adapt to the signal transmission requirements of target communication frequency bands such as GSM and DCS.

[0023] 5. GSM: Global System for Mobile Communications, is a second-generation mobile communication technology standard that covers multiple core operating frequency bands and is the main compatibility target for multi-band compatible radio frequency circuits.

[0024] 6. DCS: The full name of DCS is Digital Cellular System. It is a frequency band standard derived from GSM technology. It belongs to the category of mobile communication radio frequency bands and is a common adaptation frequency band for multi-band radio frequency circuits.

[0025] Furthermore, to achieve the circuit structure modification of the multi-band RF transceiver circuit provided in this application, the following describes the problems existing in the traditional four-band RF transceiver circuit scheme: 1. A traditional quad-band RF transceiver circuit solution includes an RF IC, a transmitting circuit, a power amplifier circuit, a switching circuit, and a receiving circuit. The power amplifier circuit and the switching circuit are independent of each other, but they also have related matching circuits and traces in between. This design layout has the following problems: First, the space occupied by the components in the R&D design is relatively large, requiring two chips, which takes up PCB space. The matching circuit between these two components also occupies space. Furthermore, the interconnection traces between these two chips must run with a 50-ohm impedance, which places certain requirements on the PCB board: there must be a complete ground plane below the impedance line as a reference, and there cannot be sensitive traces next to it on the surface layer, otherwise it is prone to interference. Second, this circuit structure leads to increased procurement costs, mainly because the design of the power amplifier circuit and the switching circuit blocking each other requires the purchase of one power amplifier chip, one switching chip, and 4-6 matching components (inductors and capacitors). At the same time, the procurement cycle may be extended due to the procurement of multiple components, resulting in delayed delivery of the final product.

[0026] 2. In traditional four-band RF transceiver circuit designs, the receiving circuit uses four independent receiving filters, with each band employing its own dedicated filter. This design leads to the following problems: First, the component layout requires significant space, necessitating the placement of four devices and occupying PCB area. Furthermore, the matching circuitry between these four components also occupies space. Additionally, all four devices use 50-ohm impedance lines for input and 150-ohm differential lines for output. This places certain demands on the PCB: a complete ground plane must be present below the impedance lines for reference, and there should be no sensitive traces adjacent to the surface layer to prevent interference. Second, this design increases procurement costs. It requires purchasing four chips and twelve matching components (inductors and capacitors). The need to purchase multiple components may also extend the procurement cycle, potentially delaying the final product delivery.

[0027] In view of this, in order to solve the problems existing in the traditional four-band RF transceiver circuit mentioned above, and to achieve the goal of retaining the function of transmitting and receiving multi-channel signals while ensuring the signal-to-noise ratio and communication stability of the received signal, and in addition, reducing the circuit procurement cost and PCB layout space occupation, this application proposes a multi-band RF transceiver circuit.

[0028] Please refer to the following. Figure 1 , Figure 1 This is a schematic diagram of a multi-band radio frequency transceiver circuit provided in an embodiment of this application. Figure 1 As shown, the connection relationships between the various modules in the multi-band RF transceiver circuit are as follows: It should be noted that, in order to facilitate the representation of the connection relationship of the corresponding modules in the diagram, the order of "first / second / third / fourth" of the ports of the corresponding modules mentioned in the instruction manual corresponds to the numbers "1 / 2 / 3 / 4" near the connection points of the corresponding modules in the block diagram in the diagram.

[0029] The multi-band radio frequency transceiver circuit includes: a baseband chip 110, a radio frequency integrated circuit module 120, a power amplifier switch integrated module 130, a high-frequency receiving filter 140, a low-frequency receiving filter 150, and an antenna module 160. The baseband chip 110 is connected to the first port of the RF integrated circuit module 120. The second port of the RF integrated circuit module 120 is connected to the first port of the power amplifier switch integrated module 130. The second port of the power amplifier switch integrated module 130 is connected to the antenna module 160. The third port of the power amplifier switch integrated module 130 is connected to the first port of the high-frequency receiving filter 140. The fourth port of the power amplifier switch integrated module 130 is connected to the first port of the low-frequency receiving filter 150. The second port of the low-frequency receiving filter 150 is connected to the third port of the RF integrated circuit module 120. The second port of the high-frequency receiving filter 140 is connected to the fourth port of the RF integrated circuit module 120.

[0030] Based on the connection relationships between the modules in the multi-band RF transceiver circuit described above, and the circuit's operating principle, the functions of each module are described as follows: The baseband chip 110 is used to generate a transmit baseband signal and transmit the transmit baseband signal to the radio frequency integrated circuit module 120; or, to receive the demodulated baseband signal output by the radio frequency integrated circuit module 120 and convert the demodulated baseband signal into an analog signal. The radio frequency integrated circuit module 120 is used to modulate the transmit baseband signal onto the transmit carrier and perform signal power amplification processing to output the target transmit signal to the power amplifier switch integrated module 130; or, to receive the target receive signal purified by the high frequency receive filter 140 or the low frequency receive filter 150, and to obtain and output the demodulated baseband signal to the baseband chip 110 after amplifying and demodulating the target receive signal. The power amplifier switch integrated module 130 is used to amplify the target transmission signal and transmit the processed target transmission signal to the antenna module 160; or, to receive the multi-band mixed signal collected by the antenna module 160, and to guide the high-frequency received signal in the multi-band mixed signal to the high-frequency received filter 140, or to guide the low-frequency received signal in the multi-band mixed signal to the low-frequency received filter 150. The high-frequency receiving filter 140 is used to filter and purify the high-frequency receiving signal to obtain the purified target receiving signal, and to transmit the target receiving signal to the radio frequency integrated circuit module 120. The low-frequency receiving filter 150 is used to filter and purify the low-frequency receiving signal to obtain the purified target receiving signal, and to transmit the target receiving signal to the radio frequency integrated circuit module 120. The antenna module 160 is used to receive the processed target transmission signal output by the power amplifier switch integrated module 130 and transmit it to complete the signal transmission operation; or, it can collect multi-band mixed signals and transmit the multi-band mixed signals to the power amplifier switch integrated module 130 to complete the signal reception operation.

[0031] Furthermore, the baseband chip 110 is further explained. As the core of baseband signal processing in the entire RF transceiver circuit, the baseband chip 110 is used to generate the transmit baseband signal in the signal transmission link. Specifically, the transmit baseband signal is TXIQ (transmit in-phase quadrature signal), which contains in-phase and quadrature components. It can directly provide a standard baseband signal source for RF modulation and transmit the TXIQ signal to the RF integrated circuit module 120. In the signal reception link, it is used to receive the demodulated baseband signal output by the RF integrated circuit module 120 and convert the demodulated baseband signal into an analog signal through the internal signal processing unit to meet the application requirements of subsequent signal analysis and data reading.

[0032] Furthermore, the RF integrated circuit module 120 is further described. As the core of the conversion between baseband signal and RF signal, the RF integrated circuit module 120 receives the TXIQ signal transmitted by the baseband chip 110 in the signal transmission link, modulates the transmitted baseband signal onto a preset transmission carrier through the internal modulation unit, and then performs preliminary signal amplification through the power amplification unit to form a target transmitted signal that meets the transmission requirements. The target transmitted signal is then output to the power amplifier switch integrated module 130. In the signal reception link, the module receives the target received signal purified by the high-frequency receiving filter 140 or the low-frequency receiving filter 150, and sequentially performs signal amplification and demodulation processing through the internal low-noise amplification unit and demodulation unit to restore the demodulated baseband signal. The demodulated baseband signal is then transmitted to the baseband chip 110.

[0033] Furthermore, the power amplifier switch integrated module 130 is further explained. The power amplifier switch integrated module 130 integrates the functions of a traditional discrete power amplifier circuit and a switch switching circuit. In the signal transmission link, it receives the target transmission signal output from the RF integrated circuit module 120, amplifies the signal a second time through an internal power amplification unit to ensure sufficient transmission strength, and then transmits the processed target transmission signal to the antenna module 160. In the signal reception link, it receives the multi-band mixed signal collected by the antenna module 160. Through an internal switch switching unit, based on the signal frequency band characteristics, it automatically directs the high-frequency received signal in the multi-band mixed signal to the high-frequency receiving filter 140 and the low-frequency received signal to the low-frequency receiving filter 150, achieving precise splitting of the multi-band received signal. Simultaneously, the integrated design simplifies impedance matching wiring and reduces the risk of signal interference.

[0034] Furthermore, the high-frequency receiving filter 140 and the low-frequency receiving filter 150 are further explained. The high-frequency receiving filter 140 and the low-frequency receiving filter are adapted to the signal processing requirements of different frequency bands. Specifically, the high-frequency receiving filter 140 is used to filter and purify the high-frequency received signal transmitted by the power amplifier switch integrated module 130, filtering out out-of-band noise and interference signals to obtain a clean high-frequency target received signal that meets the demodulation requirements, and then transmitting the target received signal to the RF integrated circuit module 120. The low-frequency receiving filter 150 is used to filter and purify the low-frequency received signal transmitted by the power amplifier switch integrated module 130, filtering out out-of-band interference components to obtain a clean low-frequency target received signal, and then transmitting the target received signal to the RF integrated circuit module 120.

[0035] Furthermore, the antenna module 160 is described in more detail. The antenna module 160 adopts a multi-band compatible design. In the signal transmission link, it receives the processed target transmission signal output by the power amplifier switch integrated module 130 and radiates the radio frequency signal into space to complete the signal transmission operation. In the signal reception link, it collects the multi-band mixed radio frequency signal propagating in space and transmits the multi-band mixed signal to the power amplifier switch integrated module 130 to provide a signal source for subsequent signal splitting and processing, thereby realizing signal reception adaptation for multiple communication frequency bands.

[0036] As can be seen, in this embodiment, the multi-band RF transceiver circuit, through the integrated design of power amplifier switches and the independent configuration of high and low frequency receiving filters, combined with precise port connections between modules to form a closed-loop signal processing link, can not only significantly reduce PCB layout space occupation and simplify impedance matching trace design to reduce signal interference risk, but also effectively control hardware costs and shorten product delivery cycle by reducing the types and quantities of components purchased. At the same time, the division of labor and purification design of high and low frequency receiving filters can improve the filtering targeting and signal purity, reduce crosstalk of multi-band mixed signals to ensure communication quality stability, achieve compatibility and adaptation of multiple communication frequency bands and efficient signal transmission and reception conversion, and the overall architecture is simplified with low coupling of functional modules, which reduces the layout and debugging difficulty in the R&D stage and improves the convenience of later maintenance.

[0037] For a more detailed explanation of the remaining modules in the multi-band RF transceiver circuit provided in this application, please refer to [link / reference]. Figure 2 , Figure 2 This is a schematic diagram of another multi-band radio frequency transceiver circuit provided in the embodiments of this application.

[0038] It should be noted that, in order to facilitate the representation of the connection relationship of the corresponding modules in the diagram, the order of "first / second / third / fourth" of the ports of the corresponding modules mentioned in the instruction manual corresponds to the numbers "1 / 2 / 3 / 4" near the connection points of the corresponding modules in the block diagram in the diagram.

[0039] Figure 2 and Figure 1 There are some differences. Specifically, Figure 1 shows the complete front-end link structure of a multi-band RF transceiver circuit. Compared to Figure 2, it adds modules such as RF test socket 210, RF matching circuit 220, antenna matching circuit 161, antenna feed pin 162, antenna 163, transmit matching circuit 230, high-frequency band matching circuit group 240, and low-frequency band matching circuit group 250, presenting a complete front-end link including the test interface and multi-stage impedance matching from the antenna to the power amplifier switch integrated module. Figure 2, on the other hand, is a simplified core link structure, omitting the aforementioned auxiliary components and retaining only the core modules such as the baseband chip, RF integrated circuit module, power amplifier switch integrated module, antenna module, and high and low frequency receiving filters, focusing on showing the basic connection relationships between the core components. Please refer to the following for further details. Figure 2 The link structure and Figure 3 and Figure 4 The specific circuit structure shown is used to describe the connection relationships between the various modules, as well as the connection relationships between the specific components within them.

[0040] To explain in more detail the operating principle of the multi-band RF transceiver circuit provided in this application, please refer to [link / reference needed]. Figure 3 , Figure 3 This is a schematic diagram of a power amplifier switch switching circuit provided in an embodiment of this application. It should be noted that since the circuit in this application is mainly used in domestic mobile communication frequency bands, while also needing to accommodate export radio frequency circuits, the circuit involved in this application should support multiple frequency bands, including GSM 850MHz, GSM 900MHz, DCS 1800MHz, and PCS 1900MHz bands. Specifically, the "low frequency band" defined throughout the text corresponds to the GSM 850MHz and GSM 900MHz bands (frequency range 824-960MHz), and the "high frequency band" specifically corresponds to the DCS 1800MHz and PCS 1900MHz bands (frequency range 1710-1990MHz).

[0041] Specifically, such as Figure 3 As shown, the power amplifier switch switching circuit is the core front-end link in the multi-band RF transceiver circuit. This diagram clearly defines the hardware connections, component selection logic, and signal flow of the antenna module, RF test socket, RF matching circuit, power amplifier switch integrated module and its supporting control and power supply links. It is the key hardware implementation carrier of the technical solution. A functional closed loop of "antenna signal acquisition / radiation → impedance matching → power amplifier switch selection / amplification → control / power supply assurance" is constructed. Through multi-stage matching circuits, precise control links, and clean power supply design, efficient transmission and reception of 850 / 900 / 1800 / 1900MHz four-band signals is achieved, providing a stable signal source for subsequent intermediate frequency processing and baseband demodulation. The following detailed explanation of the diagram, combined with the components, ports, signals, and connections shown, and specific embodiments, is provided: In one possible embodiment, the multi-band RF transceiver circuit further includes an RF test socket and an RF matching circuit; wherein, the RF matching circuit includes a third capacitor, a second inductor, and a third inductor; the second port of the power amplifier switch integrated module is connected to the first port of the third inductor and the first port of the third capacitor; the second port of the third capacitor is connected to the first port of the second inductor and the first port of the RF test socket; the second ports of the second inductor and the second ports of the third inductor are respectively grounded; and the second port of the RF test socket is connected to the antenna module; the RF matching circuit is used for impedance matching between the power amplifier switch integrated module and the RF test socket to reduce link loss during signal transmission; the RF test socket is used to provide an interface for RF signal testing.

[0042] The specific connection relationship of the RF test socket 210, as shown in the figure, is as follows: the signal input terminal (second port) of the RF test socket 210 is connected to the resistor R1 of the antenna module 160, the signal output terminal (first port) of the RF test socket 210 is connected to the RF matching circuit 220, and the unused pin is grounded. A common selection for the RF test socket 210 is an N-type interface RF test socket 210, which is "compatible with mainstream test equipment," including signal input / output terminals, unused pins, and shielded ground pins, conforming to the industry specifications for RF circuit test interfaces.

[0043] The RF test socket 210 serves as a dedicated test interface for RF signals in multi-band RF transceiver circuits. It allows connection to test equipment such as spectrum analyzers and network analyzers during the R&D / mass production phase, directly acquiring signal parameters (such as VSWR, power, and frequency response) from the antenna or power amplifier switching terminals without circuit disassembly, facilitating debugging and performance verification. Furthermore, the shielded grounding pin in the RF test socket 210 reduces external interference introduced by the test interface, ensuring the accuracy of test data and minimizing out-of-band interference.

[0044] Furthermore, the specific components of the RF matching circuit 220 include: Figure 3 The resistors R2, inductors L2 and L3, and capacitor C3 shown in the diagram, along with the RF matching circuit 220, specifically function to achieve conjugate impedance matching between the power amplifier switch integrated module 130 (50Ω input impedance) and the RF test socket 210 / antenna module 160. Through the L-shaped network topology of L2 and C3, the impedance adaptation requirements of the four-band full frequency band are covered, ensuring that the signal reflection loss is less than or equal to -15dB. In addition, the collaborative filtering design of resistors R2 and inductors L3 can filter out out-of-band interference signals in the link, ensuring the signal purity of the input power amplifier switch integrated module, thereby achieving the design goal of reducing out-of-band interference.

[0045] As can be seen in this example, by integrating an N-type interface RF test socket with an L-type topology RF matching circuit and a collaborative filtering design, this circuit design can solve the problems of traditional testing requiring circuit disassembly, four-band impedance mismatch, and out-of-band interference. It achieves debugging without disassembly, reduces signal reflection loss, improves link signal purity, and ensures the stability of four-band transmission.

[0046] In one possible embodiment, the antenna module includes an antenna matching circuit, an antenna feed pin, and an antenna. The antenna matching circuit includes a first resistor, a fourth inductor, and a fourth capacitor. The first port of the fourth capacitor is connected to the second port of the RF test socket and the first port of the first resistor. The second port of the first resistor is connected to the first port of the fourth inductor and the antenna feed pin. The second ports of the fourth inductor and the fourth capacitor are grounded. The antenna matching circuit is used to adapt the target transmission signal output by the power amplifier switch integrated module to the impedance characteristics of the antenna module, thereby reducing power loss during signal radiation. The antenna feed pin is used to receive the processed target transmission signal output by the power amplifier switch integrated module and transmit the target transmission signal to the antenna; or, to transmit the multi-frequency mixed signal acquired by the antenna to the power amplifier switch integrated module. The antenna is used to transmit the target transmission signal or acquire the multi-frequency mixed signal and transmit the multi-frequency mixed signal to the antenna feed pin.

[0047] Based on the specific components of the antenna module and their interconnections, the following provides the component parameters used in practical applications. For example, the antenna module can consist of antenna 163 (PCB-embedded coil antenna), antenna feed pin 162, resistor R1 (470Ω, for adjusting the quality factor), inductor L4 (model adapted for four frequency bands), and capacitor C4 (0.01μF, ceramic NPO material, tolerance ±10%). R1 ​​is used to adjust the quality factor of the antenna matching circuit, avoiding power loss caused by signal resonance overshoot; L4 and C4 form an L-shaped impedance transformation network, adapting the antenna's inherent impedance (e.g., 75Ω) to a standard 50Ω impedance, reducing signal reflection loss.

[0048] Furthermore, based on the different operating modes of the circuit, the functions of the antenna module in different operating modes are described below: 1. Receiving mode: Antenna 163 in antenna module 160 is used to collect spatial four-band mixed signals and transmit them to subsequent links through the antenna feed pin, realizing the above-mentioned function of collecting multi-band mixed signals; 2. Transmitting mode: Antenna module 160 is specifically used to receive the target transmitted signal after matching and amplification, and radiate it into space, corresponding to the function of transmitting the target transmitted signal mentioned above; 3. Impedance matching: An L-type matching network is formed by R1, L4, and C4, namely "antenna resonant matching design", which adapts the typical impedance of antenna 163 to the 50-ohm standard impedance of the RF test socket, reducing the reflection loss during signal radiation / reception, so as to achieve the effect of "reducing signal power loss".

[0049] As can be seen, in this example, by using the antenna matching network 161, in combination with the coil antenna 163 and the dedicated feed pin 162, the problems of incompatibility between the antenna 163 and the link impedance and the large radiation / reception loss of the four-band signals are solved, achieving accurate antenna impedance matching to the 50Ω standard, significantly reducing reflection loss, and improving the efficiency and stability of four-band signal transmission and reception.

[0050] Based on the specific components and their connections in the corresponding modules described above, such as... Figure 3 As shown, the power amplifier switch integrated module 130 can use a quad-band compatible RF power amplifier switch integrated chip. Depending on the circuit implementation logic, this module may also include the following ports: an antenna signal input port, connected to the RF matching circuit capacitor C3, used to receive a quad-band mixed signal; a high-frequency receive signal output port, used to output the selected 1800 / 1900MHz high-frequency receive signal, corresponding to the subsequent "high-frequency receive signal guided to high-frequency receive filter" processing operation; a low-frequency receive signal output port, used to output the selected 850 / 900MHz low-frequency signal, corresponding to the subsequent "low-frequency receive signal guided to low-frequency receive filter" processing operation; a high-frequency transmit signal input port, used to receive the 1800 / 1900MHz high-frequency transmit signal output by the RF integrated circuit module, corresponding to the "target transmit signal (high-frequency component)"; a low-frequency transmit signal input port, receiving the 850 / 900MHz low-frequency transmit signal output by the RF integrated circuit module, corresponding to the "target transmit signal (low-frequency component)"; and a control signal input port, for the access mode control signal PAEN. The frequency band strobe signal BANDSW_DCS corresponds to the "mode control signal and frequency band strobe signal" mentioned later; power supply port: connected to dedicated RF power supply (VCCRF), main power supply (VBAT), and power control voltage (VAPC); ground pin: directly connected to common ground to ensure the stability of module operation; reserved ports: multiple unused spare pins for future functional upgrades (such as supporting 5G auxiliary frequency bands) to meet the compatibility expansion design in actual application scenarios.

[0051] Based on the port design of the power amplifier switch integrated module 130 described above, the signal control logic in the multi-band transceiver RF circuit will be described below with reference to specific embodiments: In one possible embodiment, the baseband chip is further configured to output a mode control signal to the power amplifier switch integrated module to control the switching of the operating mode of the power amplifier switch integrated module; wherein, when the mode control signal is at a first level, the power amplifier switch integrated module operates in transmit mode and performs power amplification of the target transmit signal; when the mode control signal is at a second level, the power amplifier switch integrated module operates in receive mode and performs path switching operation for multi-band mixed signals; the baseband chip is further configured to output a band gating signal to the power amplifier switch integrated module to control the path guidance when the power amplifier switch integrated module performs path switching operation in receive mode; wherein, when the band gating signal is at a third level, the power amplifier switch integrated module guides the high-frequency received signal to a high-frequency receive filter; when the band gating signal is at a fourth level, the power amplifier switch integrated module guides the low-frequency received signal to a low-frequency receive filter.

[0052] Since the baseband chip outputs corresponding signals to the power amplifier switch integrated module, the power amplifier switch integrated module has the following functions: 1. Mode switching: In response to the PAEN signal, a high level (i.e., the first level) enters the transmit mode, activating the internal power amplifier unit to amplify the target transmitted signal; a low level (i.e., the second level) enters the receive mode, shutting down the power amplifier unit and switching to the frequency band selection state. 2. Frequency band selection: In response to the BANDSW_DCS signal, a third level selects the high-frequency band (1800 / 1900MHz), and a fourth level selects the low-frequency band (850 / 900MHz), achieving time-division multiplexing of four frequency bands for orderly transmission and reception, avoiding frequency band crosstalk. 3. Power amplification: In transmit mode, linear power amplification is performed on the high-frequency / low-frequency target transmitted signals, and the output power conforms to the GSM network communication standard.

[0053] For example, the specific components and implementation logic of the power amplifier enable signal link (PAEN) are as follows: the power amplifier enable signal output by the baseband chip is connected to the power amplifier switch integrated module 130 via resistor R5 (1kΩ, current limiting). One end of capacitor C7 (coupling capacitor) is connected to the connection node between R5 and the module, and the other end is grounded. The voltage level is defined as triggering the transmit mode when the first level (3.3V) is reached, and triggering the receive mode when the second level (0V) is reached, thus adapting to the general power supply standard of RF circuits. The specific function of the power amplifier enable signal link is to accurately control the operating mode of the power amplifier switch integrated module. Capacitor C7 filters out high-frequency noise in the control signal to avoid erroneous mode switching.

[0054] For example, the specific components and implementation logic of the band selection signal link (BANDSW_DCS) are as follows: the band selection signal output by the baseband chip is connected to the power amplifier switch integrated module 130 via capacitor C6 (100pF, coupling capacitor). The level is defined as the third level (3.3V) for selecting the 1800 / 1900MHz high-frequency band, and the fourth level (0V) for selecting the 850 / 900MHz low-frequency band. This level design is to maintain consistency with the mode control signal level standard and avoid logical conflicts. The specific function of the band selection signal link is to realize four-band splitting in the receiving mode. Capacitor C6 isolates the DC component and ensures the purity of the selection signal.

[0055] As can be seen, in this example, by integrating the power amplifier module and the switching module into the power amplifier-switching integrated module, and by providing a dual-level precision control link for the corresponding port, i.e., the mode enable and frequency band gating are designed independently, this circuit design can solve the problems of multi-band crosstalk, false triggering of mode switching, and insufficient expansion capability. It can achieve orderly four-band time-division transmission and reception, stable and interference-free mode switching, output power that meets the corresponding frequency band standard, and support subsequent function upgrades.

[0056] Combination Figure 3 The component design and specific connection relationships are described below. Figure 3 The corresponding power supply and filtering circuits include the dedicated RF power supply link (VCCRF), the main power supply voltage link (VBAT), and the power control voltage link (VAPC).

[0057] Specifically, the dedicated radio frequency (VCCRF) power supply link consists of a dedicated radio frequency power supply voltage (preferably 3.3V) connected to the power amplifier switch integrated module 130 via a resistor R4 (220Ω, current limiting), without any additional filter capacitors (the module has an integrated filter unit). Its function is to provide clean power to the core radio frequency circuits (switching unit, low-noise amplification unit) of the power amplifier switch integrated module, avoiding interference from digital circuit power supply and ensuring the stability of radio frequency signal processing.

[0058] Specifically, the main power supply voltage link (VBAT) consists of a multi-capacitor filter network (π-type topology) composed of the main power supply voltage (preferably 4.2V, powered by lithium battery) and capacitors C8 (10μF), C9 (1μF), C10 (0.1μF), and C11 (100pF), which is connected to the power amplifier switch integrated module 130. Its function is to filter out low-frequency ripple and high-frequency noise in the power supply line through the cooperation of multiple capacitors, and provide low-noise and highly stable DC power supply, which meets the "clean power supply" design specifications of radio frequency circuits.

[0059] Specifically, the power control voltage link (VAPC) consists of a power control voltage (adjustable from 0.8-2.5V) divided by resistors R6 (10kΩ) and R7 (10kΩ) (voltage division ratio 1:1), then filtered by capacitor C12 (100pF) before being connected to the power amplifier switch integrated module 130. Its function is to linearly adjust the output power of the power amplifier unit by adjusting the input voltage, adapting to different communication scenarios (such as reducing power for energy saving in short-range communication, and increasing power for coverage in long-range communication).

[0060] As can be seen, in this example, by using dedicated power supply for multiple links, hierarchical filtering design, and main power supply filtering and voltage divider power control, this power supply design can solve the problems of power supply noise interfering with radio frequency signals and output power not being adaptable to multiple scenarios, achieving low noise and high stability in power supply, flexible and adjustable power, adapting to long-distance and short-distance communication scenarios, and ensuring continuous and reliable operation of the module.

[0061] It can be seen that, as Figure 3 As shown in Figure 3, the front-end core link of the multi-band transceiver RF circuit integrates an antenna module, RF test socket, RF matching circuit, and power amplifier switch integrated module, along with supporting control and power supply links. Through multi-stage impedance matching, dual-level precise control, and clean power supply design, it achieves efficient four-band transceiver operation at 850 / 900 / 1800 / 1900MHz, reduces signal loss, avoids frequency band crosstalk, supports debugging without disassembly, and provides a stable signal source for subsequent processing.

[0062] In one possible embodiment, the multi-band RF transceiver circuit further includes a transmit matching circuit; wherein the transmit matching circuit includes a first capacitor, a second capacitor, and a first inductor, the first port of the first capacitor is connected to the second port of the RF integrated circuit module and the first port of the first inductor, the second port of the first inductor is connected to the first port of the second capacitor and the first port of the power amplifier switch integrated module, and the second ports of the first capacitor and the second capacitor are respectively grounded; the transmit matching circuit is used to achieve impedance matching of the target transmit signal output by the RF integrated circuit module, so as to reduce reflection loss during signal transmission.

[0063] In this context, the second port of the RF integrated circuit module is merely a designation used to distinguish it from the other ports when describing the connection relationship. In actual circuit connections, to achieve efficient four-band transmission and reception, the second port of the RF integrated circuit module in this application actually needs to be divided into a low-frequency transmission port and a high-frequency transmission port to adapt to the functional requirements of dual-band transmission. Since the transmission matching circuit can be applied to both the high-frequency and low-frequency components of the target transmitted signal, the first inductor can correspond to... Figure 4 L1 and L4 in the diagram, the second capacitor can correspond to Figure 4 C2 and C14 in the first capacitor can correspond to Figure 4 C1 and C13 in, that is, in Figure 4 The transmission matching circuit is divided into two parallel branches according to the frequency band characteristics of the target transmission signal, which are adapted to the 1800 / 1900MHz high-frequency component and the 850 / 900MHz low-frequency component respectively.

[0064] Furthermore, the two branches are based on the LC impedance transformation principle, achieving targeted frequency band adaptation through precise matching of component parameters. In the high-frequency branch, L1, C1, and C2 form an L-shaped matching network, utilizing the impedance characteristics of inductors to high-frequency signals to accurately convert the output impedance of the RF integrated circuit module to the 50Ω standard impedance required by the power amplifier switch integrated module, while suppressing low-frequency noise. In the low-frequency branch, L4, C13, and C14 adopt the same topology logic to adapt to the impedance matching requirements of low-frequency signals and block high-frequency interference components. The two branches maximize power transmission through conjugate matching conditions (equal real parts and canceling imaginary parts), and combined with the filtering characteristics of capacitors, further improve the purity of the target transmitted signal.

[0065] As can be seen, in this example, the transmit matching circuit, through its dual-branch split design, solves the technical pain point of traditional single-branch matching circuits that cannot simultaneously handle high and low frequency bands. Each branch is adapted to the corresponding frequency band signal, controlling the full-band reflection loss to ≤-14dB while achieving efficient clutter filtering, significantly improving the transmission efficiency of the target transmit signal to the power amplifier switching integrated module. Its symmetrical topology is compact, with high component reusability, perfectly meeting the integrated design requirements of multi-band RF transceivers.

[0066] Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a radio frequency transceiver circuit provided in an embodiment of this application, as shown below. Figure 4 As shown, In one possible embodiment, the multi-band RF transceiver circuit further includes a high-frequency band matching circuit group. The second port of the high-frequency band matching circuit group is connected to the fourth port of the RF integrated circuit module, and the first port of the high-frequency band matching circuit group is connected to the second port of the high-frequency receiving filter. The high-frequency band matching circuit group is used to achieve impedance matching between the fourth port of the RF integrated circuit module and the first port of the high-frequency receiving filter to reduce the transmission reflection loss of the high-frequency received signal. In addition, the high-frequency band matching circuit group is also used to filter out low-frequency interference components in the high-frequency received signal and adapt to the input signal amplitude threshold of the high-frequency receiving filter.

[0067] The high-frequency matching circuit group includes the following components: inductor L10 (10th), capacitor C24 (24th), capacitor C25 (25th), inductor L11 (11th), capacitor C26 (26th), and capacitor C27 (27th). The first ports of C24, C25, C26, and C27 together form the second port of the high-frequency matching circuit group, which is connected to the fourth port of the RF integrated circuit module. The second ports of C24 and C25 are connected to the two ends of L10, and the second ports of C26 and C27 are connected to the two ends of L11. Furthermore, the second ports of C24, C25, C26, and C27 together form the first port of the high-frequency matching circuit group, which is connected to the second port of the high-frequency receiving filter.

[0068] One point that needs explanation is why, even though the high-frequency receiving filter has already removed low-frequency interference, an additional high-frequency matching circuit is still needed. The reason is that while the high-frequency receiving filter can filter out most of the 850MHz-900MHz low-frequency interference through its passband characteristics (1800MHz-1900MHz), a small amount of leakage exists at the frequency edges (such as 1790MHz-1810MHz). The high-frequency matching circuit further attenuates the leakage component (attenuation ≥20dB) through the frequency selectivity of the LC network (such as the tenth inductor L10 and the twenty-fourth capacitor C24), preventing low-frequency interference from entering the RF integrated circuit module and affecting demodulation accuracy. Simultaneously, the matching circuit can adapt to the amplitude fluctuations of the high-frequency receiving filter's output signal, stabilizing the signal amplitude within the input threshold range of the RF integrated circuit module and preventing signal overload distortion. Furthermore, the circuit employs a symmetrical dual LC branch topology (C24-L10-C25, C26-L11-C27), a derivative structure of the T-type impedance transformation network. By precisely matching the inductor and capacitor parameters, the impedances of the fourth port of the RF integrated circuit module and the first port of the high-frequency receiving filter satisfy the conjugate matching condition (equal real parts, canceling imaginary parts), maximizing high-frequency signal power transmission and reducing reflection loss. Moreover, utilizing the frequency domain characteristics of capacitors ("passing high frequencies, blocking low frequencies") and inductors ("passing low frequencies, blocking high frequencies"), the 850 / 900MHz low-frequency interference components are shunted to ground by L10 and L11, while the 1800 / 1900MHz high-frequency received signal can be smoothly transmitted through C24-C27, achieving out-of-band interference suppression. In addition, this circuit design can also appropriately adjust the amplitude of the high-frequency received signal through the inherent attenuation characteristics of the LC network, making it match the input amplitude threshold of the high-frequency receiving filter and avoiding signal overload distortion.

[0069] As can be seen, in this example, the circuit design achieves precise impedance matching through symmetrical LC branches, significantly reducing reflection loss; it efficiently filters out low-frequency interference, ensuring the purity of high-frequency signals; and it synchronously adapts to the filter amplitude threshold to avoid distortion. The circuit structure is compact, with strong synergy among passive components, balancing transmission efficiency and signal integrity, and adapting to multi-band RF transceiver requirements.

[0070] In one possible embodiment, the multi-band RF transceiver circuit further includes a low-frequency band matching circuit group. The second port of the low-frequency band matching circuit group is connected to the third port of the RF integrated circuit module, and the first port of the low-frequency band matching circuit group is connected to the second port of the low-frequency receiving filter. The low-frequency band matching circuit group is used to achieve impedance matching between the third port of the RF integrated circuit module and the first port of the low-frequency receiving filter to reduce the transmission reflection loss of the low-frequency received signal. The low-frequency band matching circuit group is also used to filter out high-frequency interference components in the low-frequency received signal and adapt to the input signal amplitude threshold of the low-frequency receiving filter.

[0071] The low-frequency matching circuit group includes the following components: inductor L8 (eighth), capacitor C20 (twentieth), capacitor C21 (twenty-first), inductor L9 (ninth), capacitor C22 (twenty-second), and capacitor C23 (twenty-third). The first ports of C20, C21, C22, and C23 together form the second port of the low-frequency matching circuit group, which is connected to the third port of the RF integrated circuit module. The second ports of C20 and C21 are connected to the two ends of L8, and the second ports of C22 and C23 are connected to the two ends of L9. Furthermore, the second ports of C20, C21, C22, and C23 together form the first port of the low-frequency matching circuit group, which is connected to the second port of the low-frequency receiving filter.

[0072] The system employs a symmetrical dual-LC branch topology (C20-L8-C21, C22-L9-C23), a derivative structure of the T-type impedance transformation network. By precisely matching the inductor and capacitor parameters, the third port of the RF integrated circuit module and the first port of the low-frequency receiving filter meet the conjugate matching condition (equal real parts, canceling imaginary parts), maximizing the power transmission of the 850 / 900MHz low-frequency signal and reducing reflection loss. Utilizing the inductor's "high impedance at high frequencies, low impedance at low frequencies" characteristic, 1800 / 1900MHz high-frequency interference components are blocked by L8 and L9, unable to pass through the branches; while the low-frequency received signal can smoothly penetrate the inductor, achieving efficient out-of-band interference suppression in conjunction with capacitive coupling. The LC network, through its inherent attenuation characteristics, precisely adjusts the amplitude of the low-frequency received signal to match the input amplitude threshold of the low-frequency receiving filter, avoiding distortion caused by signal overload.

[0073] As can be seen in this example, the design achieves precise impedance matching through symmetrical LC branches, reducing reflection loss; efficiently filters out high-frequency interference, ensuring the purity of low-frequency signals; and synchronously adapts to the filter amplitude threshold to avoid distortion. The circuit structure is compact, the passive components are highly coordinated, balancing transmission efficiency and signal integrity, and adapting to multi-band RF transceiver requirements.

[0074] In one possible embodiment, both the high-frequency receiving filter and the low-frequency receiving filter are combined surface acoustic wave filters, wherein the passband frequency of the high-frequency receiving filter covers the 1800MHz to 1900MHz frequency band, and the passband frequency of the low-frequency receiving filter covers the 850MHz to 900MHz frequency band.

[0075] The high-frequency receiving filter receives the high-frequency signal transmitted from the preceding circuitry at its first port, and its second port is electrically connected to the first port of the high-frequency matching circuit group. The second port of the high-frequency matching circuit group is connected to the fourth port of the RF integrated circuit module. Similarly, the low-frequency receiving filter receives the low-frequency signal at its first port, and its second port is connected to the first port of the low-frequency matching circuit group. The second port of the low-frequency matching circuit group is connected to the third port of the RF integrated circuit module, forming a cascaded transmission structure of "filter-matching circuit group-RF IC," ensuring precise signal path connection and controllable transmission loss.

[0076] The working mechanism of the two-in-one surface acoustic wave filter is based on the piezoelectric effect. It realizes the mutual conversion between electrical signals and surface acoustic waves through a periodic grid electrode structure. Only the target frequency band signal is allowed to pass through the resonant path matched by the electrode period, while non-target frequency band signals are reflected or attenuated.

[0077] For example, during operation, the multi-band mixed signal first enters two types of filters: a high-frequency receiving filter precisely selects 1800MHz / 1900MHz signals, blocking low-frequency interference; a low-frequency receiving filter only allows 850MHz / 900MHz signals, suppressing high-frequency noise. The target signal, initially purified by the filters, then enters the corresponding matching circuit group: on the one hand, impedance conjugate matching is achieved through an LC network, adapting the filter output impedance to the 50Ω standard impedance required by the RF integrated circuit module, reducing signal reflection loss; on the other hand, residual out-of-band interference is further filtered out, and the signal amplitude is adjusted through inherent attenuation characteristics to match the input threshold requirements of the RF integrated circuit module, avoiding overload distortion.

[0078] Furthermore, such as Figure 4As shown, the circuit also includes components designed to support the low-frequency receiving filter, high-frequency receiving filter, low-frequency band matching circuit group, and high-frequency band matching circuit group. Specifically, one end of the nineteenth capacitor C19 is connected to the low-frequency receiving signal input, and the other end is connected to one end of the fifth inductor L5 and the input port of the low-frequency receiving filter; the other end of L5 is directly connected to the common ground. One end of the sixth inductor L6 is connected to the high-frequency receiving signal input, and the other end is connected to one end of the seventh inductor L7 and the input port of the high-frequency receiving filter; the other end of L7 is directly connected to the common ground. One end of C28 is connected to the output node of the high-frequency band matching circuit group (i.e., the connection node of L11 and C26), and the other end is directly connected to the common ground. C19 acts as a coupling capacitor, isolating the DC component in the low-frequency receiving signal, allowing only 850 / 900MHz low-frequency AC signals to pass through, while initially suppressing high-frequency noise from entering the low-frequency receiving filter, ensuring the purity of the low-frequency signal's AC transmission. L5, acting as a high-frequency choke, presents high impedance to 1800 / 1900MHz high-frequency signals, blocking high-frequency interference from entering the low-frequency receiving filter. It also provides a stable ground reference for low-frequency signals, preventing crosstalk caused by signal potential fluctuations. L6, also acting as a low-frequency choke, presents high impedance to 850 / 900MHz low-frequency signals, blocking low-frequency interference from entering the high-frequency receiving filter and ensuring accurate input of 1800 / 1900MHz high-frequency signals. L7 works in conjunction with L6 to enhance filtering, bypassing a small amount of residual low-frequency noise that penetrates L6 to ground, further improving the purity of the high-frequency received signal. C28, acting as a high-frequency bypass capacitor, bypasses residual high-frequency noise in the output signal of the high-frequency matching circuit group to ground, purifying the signal input to the RF integrated circuit module, while stabilizing the circuit potential and reducing electromagnetic interference.

[0079] As can be seen, in this example, the two-in-one surface acoustic wave filter achieves precise separation of dual-band signals through heterogeneous integration and dual-mode excitation design, replacing four traditional single-band filters. This halves the number of components and significantly contributes to circuit miniaturization. Combined with the cascaded structure of "filter-matching circuit group-RF IC," the filter first performs coarse screening, and the matching circuit group then optimizes the transmission characteristics, doubly ensuring signal purity and transmission efficiency. This effectively resolves the contradiction between signal crosstalk and circuit integration in multi-band communication, improving the overall performance of multi-band RF transceiver circuits.

[0080] The following is combined with Figure 4 For the link design not covered in the previous section, describe the following circuit design principles: In one possible embodiment, the multi-band RF transceiver circuit also includes a dedicated RF power supply voltage (VCCRF) link design. The dedicated RF power supply voltage corresponds to VCCRF, and its power supply link adapter diagram shows the following component layout: the first port of the ferrite bead is connected to VCCRF, and the second port is divided into two branches. The first branch is shared with the first ports of capacitors C16 and C17, while the second ports of both C16 and C17 are directly connected to a common ground. The second branch is connected to the first port of resistor R9, and the second port of R9 is shared with the first port of capacitor C18, which is also connected to a common ground.

[0081] The functional logic of this link is as follows: the ferrite bead is used to suppress high-frequency conducted interference in the VCCRF power supply and block the transmission of noise to the RF integrated circuit module; C16 and C17 form a parallel decoupling capacitor group to filter out medium and high frequency ripple in the power supply; R9 and C18 form an RC low-pass filter network to further attenuate low-frequency noise, and finally provide low-noise and highly stable DC power supply for the RF core circuit of the RF integrated circuit module, so as to avoid power supply interference affecting the modulation and demodulation performance of RF signals.

[0082] In one possible embodiment, the radio frequency integrated circuit module further includes a baseband signal interface link, which contains 6 signals, as indicated in the figure. In this circuit, signal I is the in-phase component of the baseband signal, with its first port connected to the in-phase component output pin of the baseband chip and its second port connected to the in-phase component input pin of the RF integrated circuit module; signal IB is the complementary signal of the in-phase component, with its first port connected to the complementary output pin of the baseband chip and its second port connected to the complementary input pin of the RF integrated circuit module; signal Q is the quadrature component of the baseband signal, with its first port connected to the quadrature component output pin of the baseband chip and its second port connected to the quadrature component input pin of the RF integrated circuit module; signal QB is the complementary signal of the quadrature component, with its first port connected to the complementary output pin of the baseband chip and its second port connected to the complementary input pin of the RF integrated circuit module; signal LE is the latch enable signal, with its first port connected to the latch control output pin of the baseband chip and its second port connected to the latch control input pin of the RF integrated circuit module; and signal SCLK is the serial clock signal, with its first port connected to the serial clock output pin of the baseband chip and its second port connected to the serial clock input pin of the RF integrated circuit module.

[0083] The functions of this link are as follows: I, IB and Q, QB work together to transmit differential baseband signals, improve signal anti-interference capability, and provide a precise baseband signal source for the IQ modulation unit of the RF integrated circuit module; LE and SCLK work together to realize synchronous latching of serial data, ensuring accurate transmission of configuration parameters and status feedback data between the baseband chip and the RF integrated circuit module.

[0084] As can be seen, in this example, the problems of power supply interference and signal crosstalk are effectively solved by multi-stage filtering and decoupling design of the power supply link and differential + synchronous control interface design of the baseband signal. This not only ensures the stable operation of the RF core circuit and the transmit buffer, but also improves the transmission accuracy of the baseband signal, laying the foundation for high-quality processing of multi-band RF transceiver signals.

[0085] In one possible embodiment, the multi-band RF transceiver circuit further includes a transmit buffer power supply link. In the transmit buffer power supply voltage (corresponding to VCCTXBUF) link, the connection relationship between resistor R8 and capacitor C15 is as follows: the first port of R8 is connected to the transmit buffer power supply voltage VCCTXBUF, and the second port is divided into two paths—one directly connected to the transmit buffer power supply pin of the RF integrated circuit module, and the other shared with the first port of capacitor C15; the second port of C15 is directly connected to the common ground terminal. Their functions are: R8 acts as a current-limiting resistor, limiting the instantaneous current peak of the VCCTXBUF power supply link to prevent excessive current from damaging the transmit buffer inside the RF integrated circuit module; C15 acts as a decoupling capacitor, filtering out voltage ripple and high-frequency noise in the VCCTXBUF power supply, ensuring the stability of the transmit buffer's operating voltage, thereby improving the driving capability and transmission linearity of the target transmit signal and avoiding transmit signal distortion caused by power supply fluctuations.

[0086] In one possible embodiment, Figure 4 corresponds to the integrated transmission link of control signals for a multi-band radio frequency transceiver circuit. This link is designed with precise control and anti-interference as its core objectives, and constructs a comprehensive signal interaction architecture.

[0087] Specifically, this includes: 1. A general-purpose output pin is directly led out to the outside of the RF integrated circuit module, serving as a flexible, software-configurable interface. It can output high and low level signals according to actual needs, enabling control of external auxiliary circuits or feedback of circuit operation status, significantly improving circuit expandability; 2. A high-frequency suppression inductor L12 is connected in series in the signal transmission path. Its first port connects to the signal output pin of the RF integrated circuit module, and its second port connects to the external signal interface. With its high impedance characteristics against high-frequency interference components, it effectively blocks noise transmission, ensuring signal integrity; 3. The two ends of the serial data signal SDATA are connected to the serial data output pin of the baseband chip and the serial data input pin of the RF integrated circuit module, respectively. This is specifically used to transmit serial data such as configuration parameters and status feedback between the two, achieving precise communication with a synchronization mechanism; 4. The RF power enable signal RFVCCEN and the voltage-controlled crystal oscillator enable signal VCXOEN are connected to the control output pin of the baseband chip and the power enable pin of the RF integrated circuit module and the enable pin of the VCXO, respectively. Through coordinated control of the RF circuit power supply on / off and the VCXO start / stop, on-demand power supply is achieved, significantly reducing system power consumption.

[0088] As can be seen, in this example, the entire control link adopts differential transmission and shielding design, which effectively reduces signal crosstalk, ensures the accurate execution of various control commands, and provides reliable support for the overall coordinated operation of the circuit.

[0089] In one possible embodiment, the digital power supply link in Figure 4 focuses on low noise and high stability, providing dedicated power supply for core components and serving as the energy foundation for precise circuit operation. The digital power supply voltage VCCSDM, as the dedicated power supply voltage for the modulator inside the RF integrated circuit module, is directly connected to the modulator's power pin. Stable power output ensures signal conversion accuracy, providing crucial support for precise modulation and demodulation of RF signals. Furthermore, the multi-band RF transceiver circuit also includes a voltage-controlled crystal oscillator (VCXO). The VCXO is connected to the core frequency reference source and the RF integrated circuit module, respectively. The VCXO fine-tunes its clock frequency using the control signal from the RF integrated circuit module, adapting to frequency deviation requirements in different communication scenarios and avoiding signal synchronization errors. Correspondingly, the dedicated power supply voltage VCCVCXO for the VCXO is directly connected to the VCXO's power pin, providing low-noise DC power, a prerequisite for the VCXO to achieve precise frequency fine-tuning. Decoupling capacitors C29 and C30 are placed near their respective power supply pins. The first port of C29 is connected to the power supply terminal of the VCXO, and the first port of C30 is connected to the signal node of the core frequency reference source. The second ports of both are directly grounded, forming a local energy reservoir. This system can efficiently filter out voltage ripple and high-frequency noise in the power supply link, stabilize the voltage potential, and prevent power supply fluctuations from affecting the working performance of core devices such as the modulator and VCXO. This ensures that the power supply quality meets the high-precision requirements of multi-band RF transceivers.

[0090] In one possible embodiment, the frequency reference link in Figure 4 is designed with high stability and low jitter as its core features, providing a precise clock synchronization basis for multi-band signal transmission and reception. The multi-band RF transceiver circuit also includes a core frequency reference source (26MHz passive crystal oscillator), which is connected to the clock input port of the RF integrated circuit module. The crystal serving as the core frequency reference source is a 26MHz passive crystal oscillator, whose pins are respectively connected to the signal node and common ground terminal of the core frequency reference source. It provides a reference clock through its own stable inherent resonant frequency, strictly controlling frequency accuracy to meet the synchronization requirements of multi-band communication. The signal terminal of the core frequency reference source is directly connected to the clock input pin of the RF integrated circuit module. After shaping and amplifying the original signal output by the crystal, it outputs a precise clock signal, providing a unified frequency reference for the transmission and reception of 850 / 900MHz and 1800 / 1900MHz multi-band signals, effectively reducing phase noise and improving communication bit error rate performance. The entire frequency reference link adopts a compact layout, minimizing lead length and reducing the impact of parasitic parameters on the signal, ensuring low jitter transmission of the clock signal, and laying a solid foundation for accurate modulation, demodulation, and synchronous transmission and reception of multi-band RF signals.

[0091] As can be seen, in this application, combined with Figure 2 , Figure 3 and Figure 4 All circuit designs, based on a modular and integrated design, achieve efficient transmission and reception and precise processing of dual-band signals. The dual-branch split transmit matching circuit, working in conjunction with dedicated high- and low-frequency band matching circuits, significantly reduces reflection loss during signal transmission. Combined with a two-in-one integrated filter, this provides dual protection, effectively filtering out cross-band interference and ensuring signal purity. The power supply links for the RF core circuit and transmit buffer employ a multi-stage filtering and decoupling design, along with a high-precision frequency reference source, providing low-noise and highly stable operation for core components and avoiding performance impacts caused by power supply fluctuations and frequency drift. The baseband signal utilizes differential transmission and synchronization control mechanisms to enhance anti-interference capabilities and ensure signal transmission accuracy; coordinated control of the power enable signal enables on-demand power supply, significantly reducing system power consumption. Simultaneously, the compact layout and component integration design of the circuit significantly reduce the overall size, while high-frequency suppression devices enhance electromagnetic compatibility and improve adaptability in complex environments. The overall architecture comprehensively solves core problems such as impedance mismatch, signal crosstalk, and frequency inaccuracy in multi-band communication, while taking into account the requirements of low-loss transmission, high signal integrity, low power consumption operation, and miniaturization. It significantly improves the stability and reliability of communication links and can be flexibly adapted to multi-scenario and multi-band RF communication applications.

[0092] Furthermore, this application also provides a multi-band radio frequency transceiver module, including any of the multi-band radio frequency transceiver circuits described in the above embodiments.

[0093] Furthermore, this application also provides a terminal device, including any of the multi-band radio frequency transceiver modules involved in the above embodiments.

[0094] It should be understood that any solutions and products implemented based on the aforementioned multi-band radio frequency transceiver circuit should fall within the protection scope of this application.

[0095] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0096] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A multi-band radio frequency transceiver circuit, characterized in that, include: Baseband chip, RF integrated circuit module, power amplifier switch integrated module, high frequency receiving filter, low frequency receiving filter and antenna module; The baseband chip is connected to the first port of the radio frequency integrated circuit module, the second port of the radio frequency integrated circuit module is connected to the first port of the power amplifier switch integrated module, the second port of the power amplifier switch integrated module is connected to the antenna module, the third port of the power amplifier switch integrated module is connected to the first port of the high-frequency receiving filter, the fourth port of the power amplifier switch integrated module is connected to the first port of the low-frequency receiving filter, the second port of the low-frequency receiving filter is connected to the third port of the radio frequency integrated circuit module, and the second port of the high-frequency receiving filter is connected to the fourth port of the radio frequency integrated circuit module. The baseband chip is used to generate a transmit baseband signal and transmit the transmit baseband signal to the radio frequency integrated circuit module; Alternatively, the demodulated baseband signal output by the radio frequency integrated circuit module can be received and converted into an analog signal; The radio frequency integrated circuit module is used to modulate the transmit baseband signal onto the transmit carrier and perform signal power amplification processing to output the target transmit signal to the power amplifier switch integrated module; or, to receive the target receive signal purified by the high frequency receive filter or the low frequency receive filter, and to obtain and output the demodulated baseband signal to the baseband chip after amplifying and demodulating the target receive signal. The power amplifier switch integrated module is used to amplify the target transmitted signal and transmit the processed target transmitted signal to the antenna module; or, to receive the multi-band mixed signal collected by the antenna module and to guide the high-frequency received signal in the multi-band mixed signal to the high-frequency received filter, or to guide the low-frequency received signal in the multi-band mixed signal to the low-frequency received filter. The high-frequency receiving filter is used to filter and purify the high-frequency received signal to obtain the purified target received signal, and to transmit the target received signal to the radio frequency integrated circuit module. The low-frequency receiving filter is used to filter and purify the low-frequency received signal to obtain the purified target received signal, and to transmit the target received signal to the radio frequency integrated circuit module. The antenna module is used to receive the processed target transmission signal output by the power amplifier switch integrated module and transmit it to complete the signal transmission operation; or, it can collect the multi-band mixed signal and transmit the multi-band mixed signal to the power amplifier switch integrated module to complete the signal reception operation.

2. The multi-band radio frequency transceiver circuit according to claim 1, characterized in that, The multi-band radio frequency transceiver circuit further includes a transmit matching circuit; wherein, the transmit matching circuit includes a first capacitor, a second capacitor, and a first inductor, the first port of the first capacitor is connected to the second port of the radio frequency integrated circuit module and the first port of the first inductor, the second port of the first inductor is connected to the first port of the second capacitor and the first port of the power amplifier switch integrated module, and the second port of the first capacitor and the second port of the second capacitor are respectively grounded; The transmit matching circuit is used to achieve impedance matching of the target transmit signal output by the radio frequency integrated circuit module, so as to reduce reflection loss during signal transmission.

3. The multi-band radio frequency transceiver circuit according to claim 2, characterized in that, The multi-band RF transceiver circuit further includes an RF test socket and an RF matching circuit; wherein, the RF matching circuit includes a third capacitor, a second inductor, and a third inductor; the second port of the power amplifier switch integrated module is connected to the first port of the third inductor and the first port of the third capacitor; the second port of the third capacitor is connected to the first port of the second inductor and the first port of the RF test socket; the second ports of the second inductor and the second ports of the third inductor are respectively grounded; and the second port of the RF test socket is connected to the antenna module. The radio frequency matching circuit is used for impedance matching between the power amplifier switch integrated module and the radio frequency test socket to reduce link loss during signal transmission. The RF test socket is used to provide an interface for testing RF signals.

4. The multi-band radio frequency transceiver circuit according to claim 3, characterized in that, The antenna module includes an antenna matching circuit, an antenna feed pin, and an antenna; wherein, the antenna matching circuit includes a first resistor, a fourth inductor, and a fourth capacitor, the first port of the fourth capacitor is connected to the second port of the RF test socket and the first port of the first resistor, the second port of the first resistor is connected to the first port of the fourth inductor and the antenna feed pin, and the second port of the fourth inductor and the second port of the fourth capacitor are grounded; The antenna matching circuit is used to adapt the target transmission signal output by the power amplifier switch integrated module to the impedance characteristics of the antenna module, so as to reduce power loss during signal radiation. The antenna feed pin is used to receive the processed target transmission signal output by the power amplifier switch integrated module and transmit the target transmission signal to the antenna; or, to transmit the multi-frequency mixed signal collected by the antenna to the power amplifier switch integrated module. The antenna is used to transmit the target signal or to collect the multi-band mixed signal and transmit the multi-band mixed signal to the antenna feed pin.

5. The multi-band radio frequency transceiver circuit according to claim 1, characterized in that, The multi-band radio frequency transceiver circuit further includes a high-frequency band matching circuit group. The second port of the high-frequency band matching circuit group is connected to the fourth port of the radio frequency integrated circuit module, and the first port of the high-frequency band matching circuit group is connected to the second port of the high-frequency receiving filter. The high-frequency band matching circuit group is used to achieve impedance matching between the fourth port of the radio frequency integrated circuit module and the first port of the high-frequency receiving filter to reduce the transmission reflection loss of the high-frequency received signal. In addition, the high-frequency band matching circuit group is also used to filter out low-frequency interference components in the high-frequency received signal and adapt to the input signal amplitude threshold of the high-frequency receiving filter.

6. The multi-band radio frequency transceiver circuit according to claim 1, characterized in that, The multi-band RF transceiver circuit further includes a low-frequency matching circuit group. The second port of the low-frequency matching circuit group is connected to the third port of the RF integrated circuit module, and the first port of the low-frequency matching circuit group is connected to the second port of the low-frequency receiving filter. The low-frequency matching circuit group is used to achieve impedance matching between the third port of the RF integrated circuit module and the first port of the low-frequency receiving filter to reduce the transmission reflection loss of the low-frequency received signal. In addition, the low-frequency matching circuit group is also used to filter out high-frequency interference components in the low-frequency received signal and adapt to the input signal amplitude threshold of the low-frequency receiving filter.

7. The multi-band radio frequency transceiver circuit according to any one of claims 1-6, characterized in that, Both the high-frequency receiving filter and the low-frequency receiving filter are two-in-one surface acoustic wave filters. The passband frequency of the high-frequency receiving filter covers the 1800MHz to 1900MHz frequency band, and the passband frequency of the low-frequency receiving filter covers the 850MHz to 900MHz frequency band.

8. The multi-band radio frequency transceiver circuit according to any one of claims 1-6, characterized in that, The baseband chip is also used to output a mode control signal to the power amplifier switch integrated module to control the switching of the operating mode of the power amplifier switch integrated module; wherein, when the mode control signal is at a first level, the power amplifier switch integrated module operates in transmit mode and performs power amplification operation of the target transmit signal; when the mode control signal is at a second level, the power amplifier switch integrated module operates in receive mode and performs path switching operation for the multi-band mixed signal; The baseband chip is also used to output a frequency band gating signal to the power amplifier switch integrated module to control the path guidance when the power amplifier switch integrated module performs the path switching operation in the receiving mode; wherein, when the frequency band gating signal is at the third level, the power amplifier switch integrated module guides the high-frequency receiving signal to the high-frequency receiving filter; when the frequency band gating signal is at the fourth level, the power amplifier switch integrated module guides the low-frequency receiving signal to the low-frequency receiving filter.

9. A multi-band radio frequency transceiver module, characterized in that, Includes the multi-band radio frequency transceiver circuit as described in any one of claims 1-8.

10. A terminal device, characterized in that, Includes the multi-band radio frequency transceiver module as described in claim 9.

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