A radio frequency front-end device, a radio frequency front-end module and a communication device

Abstract

The application provides a radio frequency front-end device, a radio frequency front-end module and a communication device, and relates to the radio frequency field, which can accurately detect a high-power signal of a receiving path in a radio frequency circuit and timely disconnect the receiving path, thereby protecting the receiving path. The radio frequency front-end device comprises a power detector and a control module. An input end of the power detector is coupled with an antenna. The antenna is further coupled with an output end of a power amplifier through a coupling connection. An output end of the power detector is connected with an input end of the control module. An output end of the control module is connected with a transceiver switch. The transceiver switch is connected with a low-noise amplifier and the antenna respectively. The power detector is used for determining a signal parameter of a coupling signal, the coupling signal being a signal received by the antenna and coupled to the power detector, and the signal parameter being used for indicating power. The control module is used for disconnecting a receiving path of the downlink signal through the transceiver switch when the signal parameter of the coupling signal is greater than a first threshold value.

Description

Technical Field

[0001] This application relates to the field of radio frequency, and more particularly to a radio frequency front-end device, a radio frequency front-end module, and a communication device. Background Technology

[0002] Radio frequency (RF) circuits in communication equipment typically include an antenna, a receiving path, and a transmitting path. The antenna is used to transmit and receive signals, the receiving path is used to transmit and process signals received by the antenna, and the transmitting path is used to transmit and process signals transmitted by the antenna.

[0003] In some possible scenarios, when a communication device is in the signal receiving state, the antenna may receive a high-power signal (e.g., above 20dBm) due to its proximity to a strong radiation source (such as a microwave oven or beauty device). This may cause some or all modules in the receiving path (such as the low noise amplifier (LNA)) to experience voltages exceeding their rated values, thereby causing the radio frequency circuit to malfunction or even be damaged. Summary of the Invention

[0004] This application provides a radio frequency (RF) front-end device, an RF front-end module, and a communication device. These devices can accurately detect high-power signals in the receiving path (i.e., the path where the LNA is located) of an RF circuit and promptly disconnect the receiving path upon detection of such high-power signals, thereby protecting the modules (LNA, etc.) in the receiving path and improving the safety of the RF circuit. Furthermore, this RF front-end device is not located in the receiving path but acquires the signal parameters of the coupled signal through coupling, thus not affecting the signal reception sensitivity and ensuring good linearity between the coupled signal power and the antenna received signal power. Additionally, the path by which the RF front-end device acquires the coupled signal reuses the signal transmission path of the transmitting path (i.e., the path where the power amplifier is located), resulting in lower implementation costs.

[0005] The following is a description of the radio frequency front-end devices, radio frequency front-end modules, and communication equipment provided in this application.

[0006] In a first aspect, a radio frequency front-end device is provided, comprising: a power detector and a control module. The input terminal of the power detector is coupled to an antenna. The antenna is also coupled to the output terminal of a power amplifier via a coupling connection. The output terminal of the power detector is connected to the input terminal of the control module. The output terminal of the control module is connected to a transceiver switch. The transceiver switch is connected to a low-noise amplifier and the antenna, respectively. The power amplifier processes uplink signals, and the low-noise amplifier processes downlink signals. The power detector determines the signal parameters of the coupled signal, which is the signal coupled from the downlink signal received by the antenna to the power detector; the signal parameters indicate the power. The control module controls the transceiver switch to disconnect the downlink signal reception path when the signal parameters of the coupled signal exceed a preset first threshold.

[0007] Based on this scheme, the RF front-end device is not located in the receiving path, but rather acquires the downlink signal power information (signal parameters) through coupling. Therefore, it does not cause additional interference or loss to the signal receiving path, which helps ensure the signal receiving sensitivity of the receiving path and guarantees good linearity between the coupled signal power and the antenna received signal power. When the antenna receives a high-power signal (i.e., a signal with signal parameters greater than a first threshold), the RF front-end device can control the receiving path to disconnect via a transmit / receive switch, thereby protecting the receiving path and preventing damage to modules such as the LNA in the receiving path due to overload. Furthermore, the path by which the RF front-end device acquires the coupled signal reuses the signal transmission path of the transmit path, resulting in lower implementation costs.

[0008] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, the control module includes a comparator and a logic module. The input of the comparator is connected to the output of the power detector, the output of the comparator is connected to the input of the logic module, and the output of the logic module is connected to a transceiver switch. The comparator is used to compare the power of the coupled signal with a first threshold, and the logic module is used to control the downlink signal receiving path to disconnect via the transceiver switch when the signal parameters of the coupled signal exceed the first threshold.

[0009] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, the signal parameter is voltage. A power detector is used to convert the coupled signal into a DC signal, and the voltage of the DC signal is used to indicate the power of the coupled signal. Based on this scheme, converting the coupled signal into a DC voltage for measurement can significantly simplify the implementation complexity of power detection. In addition, the slow-changing voltage characteristic of the DC signal (i.e., the DC signal voltage changes smoothly and slowly during the change process) is beneficial for more accurately determining the relative magnitude of the signal parameter and the first threshold, improving the accuracy of the control logic implementation. Furthermore, the slow-changing characteristic of the DC signal also helps the RF front-end device smoothly control the disconnection of the receiving path, reducing the impact on circuit components.

[0010] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, the control module is also used to control the downlink signal receiving path connection via a transmit / receive switch when the signal parameters are less than a preset second threshold. The first threshold is greater than the second threshold. Based on this scheme, setting the first threshold (shutdown threshold) higher than the second threshold (recovery threshold) to form a hysteresis window can effectively prevent the receiving path from frequently switching at the critical power point. This anti-jitter design is beneficial to improving the system's operational stability.

[0011] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, when the downlink signal receiving path is disconnected, the downlink signal is grounded through a transceiver switch. Based on this scheme, when the receiving path is disconnected, grounding the downlink signal received by the antenna allows for safer release of signal energy, avoiding interference to other parts of the circuit.

[0012] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, the control module is also used to control the downlink signal receiving path connection via a transmit / receive switch when the signal parameters are less than a first threshold. Based on this scheme, the operating state of the receiving path can be restored in a timely manner when the high-power signal disappears.

[0013] In conjunction with the RF front-end device provided in the first aspect, in some possible implementations, the first threshold is less than or equal to the rated tolerance of the low-noise amplifier. Based on this scheme, damage to the LNA in the receiving path due to overload (i.e., signal parameters exceeding the rated tolerance) can be effectively avoided.

[0014] Secondly, a radio frequency (RF) front-end module is provided, comprising: a transceiver switch, a power amplifier, a low-noise amplifier, and any RF front-end device according to the first aspect. The transceiver switch is connected to the antenna, the low-noise amplifier, and the output terminal of the control module in the RF front-end device, respectively. The output terminal of the power amplifier is coupled to the antenna, and the coupling connection point is the coupling connection point between the input terminal of the power detector in the RF front-end device and the antenna.

[0015] In conjunction with the RF front-end module provided in the second aspect, in some possible implementations, the RF front-end module also includes a balun. The unbalanced terminal of the balun is connected to the antenna. The balanced terminal of the balun is connected to the differential output of the power amplifier and the differential input of the power detector in the RF front-end device, respectively.

[0016] Thirdly, a communication device is provided, comprising: an antenna, a transceiver, and a radio frequency front-end module according to any one of the second aspects, wherein the transceiver is connected to the antenna via the radio frequency front-end module. The transceiver is used to process radio frequency signals into baseband signals or intermediate frequency signals, or to process baseband signals or intermediate frequency signals into radio frequency signals.

[0017] In conjunction with the communication equipment provided in the third aspect, in some possible implementations, the communication equipment also includes a baseband chip. The baseband chip is connected to the transceiver. The baseband chip is used to provide baseband signals or intermediate frequency (IF) signals, or, alternatively, to process baseband signals or IF signals.

[0018] Fourthly, a radio frequency (RF) front-end module is provided, including: an RF switch, a transmit path, a receive path, and a protection circuit. The transmit path is coupled to an antenna. One end of the transmit path coupled to the antenna is also connected to the input terminal of the protection circuit. The output terminal of the protection circuit is connected to the RF switch, and the receive path is also connected to the antenna via the RF switch. The transmit path is used to couple an uplink signal to the antenna for transmission, and the receive path is used to transmit a downlink signal received by the antenna. The RF switch is used to control the connection and disconnection of the receive path. The transmit path is also used to couple a downlink signal to the protection circuit. The protection circuit is used to control the receive path to disconnect via the RF switch when the signal parameter of the coupled signal exceeds a preset first threshold. The coupled signal is the signal coupled to the protection circuit. The signal parameter is used to indicate the signal power.

[0019] Among them, the radio frequency switch is the transceiver switch in the first aspect, the transmitting path is the path where the power amplifier is located in the first aspect, the receiving path is the path where the low noise amplifier is located in the first aspect, and the protection circuit is the radio frequency front-end device in the first aspect.

[0020] Based on this scheme, the protection circuit is not located in the receiving path, but rather obtains the power information (signal parameters) of the received signal through coupling. Therefore, it does not cause additional interference or loss to the signal receiving path, which helps ensure the signal receiving sensitivity of the receiving path and guarantees good linearity between the coupled signal power and the antenna received signal power. When the antenna receives a high-power signal (i.e., a signal whose signal parameters are greater than the first threshold), the protection circuit can control the receiving path to disconnect via an RF switch, thereby protecting the receiving path and preventing damage to modules such as the LNA in the receiving path due to overload. In addition, the path by which the protection circuit obtains the coupled signal reuses the signal transmission path of the transmitting path, resulting in lower implementation costs.

[0021] Based on the RF front-end module provided in the fourth aspect, in some possible implementations, the protection circuit includes a detection module and a control module. The input terminal of the protection circuit is the input terminal of the detection module, and the output terminal of the detection module is connected to the input terminal of the control module. The output terminal of the control module is connected to an RF switch. The detection module is used to detect the signal parameters of the coupled signal. The control module is used to control the receiving path to disconnect via the RF switch when the signal parameters exceed a first threshold. Based on this scheme, the detection module is independently responsible for measuring the signal parameters, and the control module is independently responsible for the judgment logic and control. This modular division of labor helps improve detection accuracy and control response speed, reduces interference between different functions, and ensures the reliability of functional implementation.

[0022] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, the signal parameter is voltage. A protection circuit is used to convert the coupled signal into a DC signal. The voltage of the DC signal is used to indicate the power of the coupled signal. Based on this scheme, converting the coupled signal into a DC voltage for measurement can significantly simplify the design complexity of the power detection circuit. Furthermore, the slow-changing characteristic of the DC signal voltage (i.e., the DC signal voltage changes smoothly and slowly during its variation) is beneficial for more accurately determining the relative magnitude of the signal parameter and the first threshold, improving the accuracy of the control logic implementation. Additionally, the slow-changing characteristic of the DC signal also helps the protection circuit smoothly control the disconnection of the receiving path, reducing the impact on circuit components.

[0023] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, when the receiving path is disconnected, the downlink signal received by the antenna is grounded through an RF switch. Based on this scheme, when the receiving path is disconnected, grounding the downlink signal received by the antenna allows for safer release of signal energy, avoiding interference to other parts of the circuit.

[0024] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, the protection circuit is also used to control the connection of the receiving path via an RF switch when the signal parameters are less than a first threshold. Based on this scheme, the operating state of the receiving path can be restored in a timely manner when a high-power signal disappears.

[0025] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, the protection circuit is also used to control the connection of the receiving path via an RF switch when the signal parameters are less than a preset second threshold. The first threshold is greater than the second threshold. Based on this scheme, setting the first threshold (shutdown threshold) higher than the second threshold (recovery threshold) to form a hysteresis window can effectively prevent the receiving path from frequently switching at the critical power point. This anti-jitter design is beneficial to improving the system's operational stability.

[0026] Based on the RF front-end module provided in the first aspect, in some possible implementations, the transmit path is coupled to the antenna via a balanced-to-unbalanced transformer (balun). The unbalanced end of the balanced-to-unbalanced transformer is connected to the antenna. Based on this scheme, the balun simultaneously performs differential-to-single-ended conversion of the transmit path and receives signal coupling, enabling efficient multiplexing of hardware resources and reducing insertion loss introduced by additional couplers. Furthermore, the balun maintains the common-mode rejection capability of the transmit channel and allows for accurate receiving signal sampling through symmetrical coupling points, improving control accuracy and circuit protection.

[0027] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, a power amplifier is also included in the transmission path. The differential output of the power amplifier is connected to the balanced end of a balun. The balun is used to convert the differential signal output by the power amplifier into a single-ended signal for transmission. Based on this scheme, the output of the power amplifier directly drives the balanced end of the balun, eliminating the impedance matching network required by traditional single-ended power amplifiers and helping to reduce insertion loss.

[0028] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, the input terminal of the protection circuit is a differential input terminal. The balanced terminal of the balun-unbalanced transformer is also connected to the differential input terminal of the protection circuit. The balun-unbalanced transformer is also used to convert the downlink signal into a differential signal for input to the differential input terminal of the protection circuit. Based on this scheme, using the differential signal output from the balun as the detection input of the protection circuit helps to cancel common-mode interference and improve signal detection sensitivity, thereby improving control accuracy and circuit protection effectiveness.

[0029] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, a low-noise amplifier (LNA) is also included in the receiving path. The first threshold is less than or equal to the rated tolerance of the LNA. Based on this scheme, damage to the LNA in the receiving path due to overload (i.e., signal parameters exceeding the rated tolerance) can be effectively avoided.

[0030] In conjunction with the RF front-end module provided in the fourth aspect, in some possible implementations, the RF switch has a transmit mode and a receive mode. When the RF switch is in transmit mode, it can control the receive path to disconnect, thereby reducing the energy of the signal conducted from the antenna to the subsequent receiving circuit and protecting the subsequent circuitry. When the RF switch is in receive mode, it can control the receive path to conduct, connecting the antenna and the subsequent receiving circuitry, thus providing lower insertion loss.

[0031] It should be understood that the second to fourth aspects of this application are consistent with or correspond to the first aspect of this application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be repeated here. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a radio frequency front-end in a communication device;

[0033] Figure 2 A schematic diagram of a radio frequency circuit provided in this application;

[0034] Figure 3 A schematic diagram of the structure of a radio frequency front-end device provided in this application;

[0035] Figure 4This is a schematic diagram of another radio frequency circuit provided in an embodiment of this application;

[0036] Figure 5 A simulation diagram provided for an embodiment of this application;

[0037] Figure 6 This is yet another simulation diagram provided for an embodiment of this application;

[0038] Figure 7 This is a schematic diagram of the structure of a communication device provided in an embodiment of this application. Detailed Implementation

[0039] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0040] References to "one embodiment" or "some embodiments" as described in this application mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0041] Furthermore, in the embodiments of this application, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design scheme described as an "example" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of the term "example" is intended to present concepts in a concrete manner. In the embodiments of this application, "of," "corresponding (relevant)," and "corresponding" may sometimes be used interchangeably, and it should be noted that their intended meanings are consistent unless their distinction is emphasized.

[0042] The application scenarios described in this application are for the purpose of more clearly illustrating the technical solutions of this application, and do not constitute a limitation on the technical solutions provided in this application. As those skilled in the art will know, with the emergence of new business scenarios, the technical solutions provided in this application are also applicable to similar technical problems.

[0043] To facilitate understanding, the background of the embodiments of this application will be introduced below.

[0044] Please refer to Figure 1 This is a schematic diagram of the structure of a radio frequency front-end in a communication device. For example... Figure 1 As shown, the RF front end includes a receiving path 102 and a transmitting path 103. The receiving path 102 and the transmitting path 103 share a transceiver switch (TRXSW) 104. Both the receiving path 102 and the transmitting path 103 are connected to the antenna 101 via the transceiver switch 104.

[0045] The receiving path 102 may include a low-noise amplifier 112 and a subsequent receiving circuit 122. The subsequent receiving circuit 122 may include a filter, mixer, intermediate frequency amplifier, demodulator, analog-to-digital converter (ADC), etc. Figure 1 (not shown in the text), which is not limited here.

[0046] The transmitting path 103 may include a power amplifier (PA) 113 and a subsequent transmitting circuit 123. The subsequent transmitting circuit 123 may include a filter, a digital-to-analog converter (DAC), an up-converter, a modulator, etc. Figure 1 (not shown in the text), which is not limited here.

[0047] Both the downstream receiving circuit 122 and the downstream transmitting circuit 123 in the RF front-end can be connected to the baseband processor of the communication device. Thus, when the RF front-end is in transmitting mode, the transceiver switch 104 connects the antenna 101 and the transmitting path 103. The baseband signal generated by the baseband processor is processed by the modules in the transmitting path 103 and then transmitted to the antenna 101 to complete the transmission. Similarly, when the RF front-end is in receiving mode, the transceiver switch 104 connects the antenna 101 and the receiving path 102. The signal received by the antenna 101 is processed by the modules in the receiving path 102 and then transmitted to the baseband processor to complete the reception. For a detailed description of the functions of each module in the RF front-end, please refer to relevant technical descriptions; further details will not be provided here.

[0048] In some possible scenarios, Figure 1 The antenna 101 may receive high-power signals of 20dBm or even higher due to its proximity to strong radiation sources (i.e., devices that radiate strong electromagnetic wave signals, such as microwave ovens and beauty devices). The voltage of this high-power signal may exceed the rated voltage of some modules in the receiving path (such as LNA), thus causing the receiving path to malfunction.

[0049] Taking an LNA as an example (it should be understood that in the following embodiments, the LNA can be replaced by a module with the same or similar input and output characteristics as the LNA, and this application does not specifically limit this), when the LNA receives a high-power signal, the internal active devices (such as transistors) may operate in the nonlinear region, causing the input and output of the LNA to no longer be an ideal linear relationship, but to exhibit nonlinear characteristics.

[0050] In the radio frequency (RF) field, the 1dB compression point is commonly used to measure amplifier linearity. The 1dB compression point refers to the input power (P1dB,in) or output power (P1dB,out) that occurs when the amplifier's gain decreases by 1dB compared to its linear gain. It should be understood that a higher 1dB compression point indicates better amplifier linearity.

[0051] Due to the electrostatic discharge (ESD) circuitry at the input port, the 1dB compression point of an LNA is typically in the range of 5-10dBm. Taking 10dBm as an example, when the input power of the LNA exceeds 10dBm, the output power no longer increases linearly with the input power but gradually stabilizes. Consequently, the LNA's output signal exhibits distortions such as harmonics and intermodulation, causing the subsequent receiving circuit to be unable to process the signal correctly. It cannot accurately determine the LNA's input power based on the magnitude of the LNA's output and the output of the subsequent receiving circuit, thus failing to accurately identify scenarios where high-power signals are received and effectively protect the receiving circuit.

[0052] To address the aforementioned issues, embodiments of this application provide a radio frequency (RF) front-end device, an RF front-end module, and a communication device. These devices can accurately detect high-power signals in the receiving path of an RF circuit and promptly disconnect the receiving path upon detection of such high-power signals, thereby protecting modules (such as LNAs) in the receiving path and improving circuit security. Furthermore, the RF front-end device is not located within the receiving path but acquires the signal parameters of the coupled signal through coupling, thus not affecting the signal reception sensitivity and ensuring good linearity between the coupled signal power and the antenna received signal power. Additionally, the protection circuit reuses the signal transmission path of the transmitting path to acquire the coupled signal, resulting in lower implementation costs.

[0053] This application provides radio frequency (RF) front-end devices and modules that can be applied to communication equipment in various communication systems. The communication equipment provided in this application can also be communication equipment in various communication systems, and is not limited thereto. Examples of some communication systems include: Universal Mobile Telecommunications System (UMTS), Wireless Local Area Network (WLAN), Wireless Fidelity (Wi-Fi) system, 4th generation (4G) mobile communication system (such as Long Term Evolution (LTE) system), 5th generation (5G) mobile communication system (such as New Radio (NR) system), future evolution communication systems (such as 6th generation (6G) mobile communication system), Vehicle-to-Everything (V2X) communication system, Device-to-Device (D2D) communication system, Internet of Things (IoT) communication system, Industrial Internet (IIoT) communication system, Global Navigation Satellite System (GNSS), and Bluetooth.

[0054] In this application embodiment, communication equipment can refer to terminal equipment or network equipment, and is not limited thereto. Examples of terminal equipment include: mobile phones, tablet computers, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in vehicle-to-everything (V2X) communication, wireless terminals in autonomous driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes. For example, the wireless terminal in autonomous driving can be a drone, helicopter, or airplane. For example, the wireless terminal in V2X communication can be in-vehicle equipment, vehicle equipment, in-vehicle modules, vehicles, or ships. The wireless terminal in industrial control can be a camera, robot, or robotic arm. Wireless terminals in a smart home can include televisions, air conditioners, robot vacuums, speakers, or set-top boxes.

[0055] Examples of network devices include: evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home-evolved Node B, or home Node B, HNB), baseband unit (BBU), access point (AP) in a Wi-Fi system, macro base station, micro base station, wireless relay node, wireless backhaul node, transmission and receiving point (TRP), etc.

[0056] Based on the above description, the radio frequency front-end devices, radio frequency front-end modules, and communication equipment provided in the embodiments of this application will be described below.

[0057] First, the radio frequency (RF) front-end device provided in the embodiments of this application will be described. This RF front-end device can be applied to RF front-end modules (FEM), system-on-chip (SoC), system-in-package (SIP) chips, multi-chip modules (MCM), etc., and the embodiments of this application do not limit its application to this.

[0058] Please refer to Figure 2 This is a schematic diagram of a radio frequency circuit provided in an embodiment of this application. Figure 2 As shown, the radio frequency circuit includes a transmit path 201, a protection circuit 202, a receive path 203, and an antenna 204. The transmit path 201 is coupled to the antenna 204. One end of the transmit path 201 coupled to the antenna 204 is also connected to the input terminal of the protection circuit 202. The output terminal of the protection circuit 202 is connected to the radio frequency switch 213, and the receive path 203 is also connected to the antenna 204 through the radio frequency switch 213.

[0059] In this embodiment, the protection circuit can also be called a radio frequency front-end device, and the radio frequency switch can also be called a transceiver switch. The receiving path is the path where the LNA is located, used to transmit and process the downlink signal received by the antenna. The transmitting path is the path where the power amplifier is located, used to transmit and process the signal to be transmitted by the antenna. Further details will not be provided hereafter.

[0060] The coupling connection between the transmission path 201 and the antenna 204 can be achieved through methods such as balun, quarter-wavelength transmission line, parallel coupling line, etc., without specific limitations here. The input terminal of the protection circuit 202 (i.e....) Figure 2 The middle arrow pointing to protection circuit 202 indicates the port where protection circuit 202 receives signals, and the output terminal of protection circuit 202 (i.e., Figure 2 The arrow pointing away from the protection circuit 202 indicates the port where the protection circuit 202 outputs its signal.

[0061] Transmit path 201 can also be referred to as uplink path, uplink channel, transmission channel, etc. In this embodiment, transmit path 201 is used to couple uplink signals to antenna 204 for transmission. For example, transmit path 201 may include modules such as power amplifier, filter, upconverter, DAC, modulator, etc. Figure 2 (Replaced by ellipses), the transmission path 201 can receive the uplink signal transmitted by the subsequent circuit. After processing the uplink signal through some or all of the above modules (i.e., power amplifier, filter, upconverter, DAC, modulator, etc.), the processed uplink signal is coupled to the antenna 204 for transmission.

[0062] In this embodiment, the transmission path 201 is also used to couple the downlink signal to the protection circuit 202 (the downlink signal coupled to the protection circuit 202 can be referred to as the coupled signal). It should be understood that the transmission path 201 is coupled to the antenna 204, and one end of the transmission path 201 coupled to the antenna 204 is also connected to the input terminal of the protection circuit 202. Therefore, the downlink signal received by the antenna 204 can be coupled to the input terminal of the protection circuit 202.

[0063] The receiving path 203 can also be referred to as a downlink path, downlink channel, receiving channel, etc. In the embodiments of this application, the receiving path 203 is used to transmit (and process) the downlink signal received by the antenna 204. In some possible implementations, such as Figure 2 In the RF circuit shown, the receiving path 203 may include modules such as an LNA, filter, mixer, intermediate frequency amplifier, demodulator, and ADC. Figure 2 (Not shown), the receiving path 203 can receive the downlink signal transmitted by the subsequent circuit. After processing the downlink signal through some or all of the above modules (i.e., LNA, filter, mixer, intermediate frequency amplifier, demodulator, ADC, etc.), it is sent to the antenna 204 for transmission.

[0064] The radio frequency switch 213 is used to control the connection and disconnection of the receiving path 203.

[0065] In some possible implementations, the RF switch 213 can have a transmit mode and a receive mode. When the RF switch 213 is in transmit mode, it can control the receive path 203 to disconnect, thereby reducing the energy of the signal conducted from the antenna to the subsequent stage of the receiving circuit and protecting the subsequent circuitry. When the RF switch 213 is in receive mode, it can control the receive path 203 to connect. This can provide lower insertion loss.

[0066] Furthermore, when the RF switch 213 is in receive mode, each module in the transmit path 201 can be turned off. This helps ensure the linearity between the coupled signal and the antenna received signal (i.e., the downlink signal). For example, even if the antenna received signal exceeds 20dBm when each module in the transmit path 201 is turned off, the amplitude of the coupled signal will still change linearly with the antenna received signal, exhibiting good linearity. It should be understood that the better the linearity between the coupled signal and the antenna received signal, the more accurately the power of the coupled signal can correspond to the power of the antenna received signal. This allows the protection circuit 202 to more accurately implement detection and control functions, improving the circuit protection effect. In this embodiment, the RF switch 213 is connected to the output terminal of the protection circuit 202. The protection circuit 202 is used to control the receive path 203 to disconnect via the RF switch 213 when the signal parameters of the coupled signal exceed a preset first threshold.

[0067] The signal parameters of the coupled signal are used to indicate the power of the coupled signal; for example, the signal parameter can be power. Or, for instance, the signal parameter can be voltage.

[0068] For example, when the signal parameter is voltage, the protection circuit 202 can convert the coupled signal into a DC signal, and the voltage of this DC signal indicates the power of the coupled signal. This simplifies the design complexity of the power detection circuit, and the gradual change characteristics of the DC signal allow the protection circuit 202 to achieve detection and control functions more smoothly and accurately.

[0069] The first threshold can be determined based on the type of signal parameter and actual needs. For example, when the signal parameter is power, the first threshold can be 10dBm, 12dBm, etc., without specific limitations.

[0070] When the signal parameters of the coupled signal exceed a first threshold, the protection circuit 202 controls the receiving path 203 to disconnect via the RF switch 213, effectively protecting the receiving path 203 and preventing damage to modules such as the LNA in the receiving path due to overload. Furthermore, since the protection circuit is not located within the receiving path but obtains the received signal parameters through coupling, it does not cause additional interference or loss to the signal receiving path, thus ensuring the signal receiving sensitivity of the receiving path and guaranteeing good linearity between the coupled signal power and the antenna received signal power. Additionally, the path by which the protection circuit obtains the coupled signal reuses the signal transmission path of the transmitting path, resulting in lower implementation costs.

[0071] Please refer to Figure 3 This is a schematic diagram of the structure of a radio frequency front-end device (i.e., protection circuit) provided in an embodiment of this application. Figure 3 As shown, the protection circuit 302 may include a detection module 312 and a control module 322. The input terminal of the protection circuit 302 is also the input terminal of the detection module 312 (i.e., the end of the transmission path 201 coupled to the antenna 204 is connected to the input terminal of the detection module 312). The output terminal of the detection module 312 is connected to the input terminal of the control module 322. The output terminal of the control module 322 is connected to the radio frequency switch 213 (i.e., the output terminal of the protection circuit 302 is also the output terminal of the control module 322).

[0072] The detection module 312 is used to detect the signal parameters of the coupled signal. This detection module can also be called a power detector. In some possible implementations, the power detector may include the function of converting the coupled signal into a DC signal and detecting the voltage of the DC signal, as described above; this is not limited to this specific implementation.

[0073] The control module 322 is used to control the receiving path 203 to disconnect via the RF switch 213 when the signal parameter is greater than a first threshold. Exemplarily, the control module 322 may include a comparator, a controller (also referred to as a logic module), etc. Figure 3 (Not shown in the diagram). The comparator can be used to compare signal parameters with a first threshold. For example, the comparator can output a low level when the signal parameter is less than the first threshold and a high level when the signal parameter is greater than the first threshold. The controller can be connected to the RF switch 213 in the receiving path 203 and can control the connection and disconnection of the receiving path 203 based on the comparator's output signal via the RF switch 213. For example, the controller can control the receiving path 203 to connect via the RF switch 213 when it receives a low level output from the comparator, and control the receiving path 203 to disconnect via the RF switch 213 when it receives a high level output from the comparator.

[0074] In some possible implementations, the protection circuit can also be used to control the connection of the receiving path via an RF switch when the signal parameters are less than a first threshold. Based on this scheme, the operating state of the receiving path can be restored in a timely manner when the high-power signal disappears.

[0075] In other possible implementations, the protection circuit can also be used to control the connection of the receiving path via an RF switch when the signal parameters are less than a preset second threshold (the second threshold is greater than the first threshold). In this way, when the signal parameters fluctuate frequently around the first threshold, it can effectively prevent the receiving path from frequently switching between connected and disconnected states, thus improving system stability.

[0076] The radio frequency front-end device provided in the embodiments of this application is described below through specific examples.

[0077] Please refer to Figure 4 This is a schematic diagram of another radio frequency circuit provided in an embodiment of this application, as shown below. Figure 4 As shown, the radio frequency circuit includes an antenna 401, a transformer 402, a transceiver switch 403 (also called an RF switch), a low-noise amplifier 404, a power amplifier 405, a power detector 406, a comparator 407, and a controller 408. The antenna 401, transceiver switch 403, and low-noise amplifier 404 are connected sequentially. The antenna 401 is also connected to one end of the primary coil of the transformer 402, and the other end of the primary coil of the transformer 402 is grounded. The secondary coil of the transformer 402 is connected to the differential output terminal of the power amplifier 405 and the differential input terminal of the power detector 406. The differential output terminal of the power detector 406 is connected to the input terminal of the comparator 407. The output terminal of the comparator 407 is connected to the input terminal of the controller 408. The output terminal of the controller 408 is connected to the transceiver switch 403.

[0078] The low-noise amplifier 404 is located in the receiving path. The transformer 402 and power amplifier 405 are located in the transmitting path. The protection circuit includes a power detector 406, a comparator 407, and a controller 408. It should be understood that other modules may also be included in the receiving and transmitting paths. Figure 4 (The ellipsis is used to indicate the ellipsis in the text). This is only an example and does not mean that this application is limited to this.

[0079] in addition Figure 4 A possible structural schematic diagram of the transceiver switch 403 is also shown as an example. For example... Figure 4 As shown, the transceiver switch 403 can consist of two switches S1 and S2, as well as a capacitor and an inductor for impedance matching. It should be understood that when the RF circuit is in receive mode, switches S1 and S2 in the transceiver switch 403 are open, the receiving path is connected, the low-noise amplifier 404 is turned on, and the power amplifier 405 is turned off. When the RF circuit is in transmit mode, switches S1 and S2 in the transceiver switch 403 are closed, the receiving path is disconnected, the low-noise amplifier 404 is turned off, and the power amplifier 405 is turned on. At this time, the transceiver switch 403 has a high impedance to ground at the resonant frequency, which will not affect the output power of the power amplifier 405.

[0080] Transformer 402 can be a balun. The end of transformer 402 containing the primary coil can be connected to the unbalanced end of the balun, while the end containing the secondary coil can be the balanced end of the balun. In other words, the balanced end of the balun can be connected to the differential output of power amplifier 405. The balun can convert the differential signal output from power amplifier 405 into a single-ended signal, which can then be transmitted through antenna 401. Thus, the output of the power amplifier directly drives the balanced end of the balun, eliminating the impedance matching network required in traditional single-ended power amplifiers and reducing insertion loss.

[0081] The balanced terminal of the balun is also connected to the differential input terminal of the power detector 406, which is used to convert the single-ended signal received by the antenna 402 into a differential signal and input it to the power detector 406. This helps to cancel common-mode interference, improve the signal detection sensitivity of the power detector 406 and the control accuracy of the controller 408, and improve the circuit protection effect.

[0082] Power detector 406 is used to convert the coupled signal into a DC level output. Comparator 407 compares the DC level output by power detector 406 with a preset first threshold, and outputs the comparison result to controller 408. The voltage of the DC signal is used to indicate the power of the coupled signal.

[0083] For example, when the DC level exceeds a first threshold, the output of comparator 407 flips to a high level, and controller 408 closes switches S1 and S2 in transceiver switch 403 based on the high level. This disconnects the receiving path, and the high-power signal received by antenna 401 is bypassed to ground through transceiver switch 403, thereby reducing the signal amplitude of low-noise amplifier 404 and protecting low-noise amplifier 404 and subsequent circuitry. In some possible examples, the first threshold can be less than or equal to the rated tolerance of the low-noise amplifier, thus effectively preventing damage to the LNA in the receiving path due to overload.

[0084] Similarly, when the DC level is less than the first threshold, comparator 407 can output a low level, and controller 408 can control switches S1 and S2 in transceiver switch 403 to open based on the low level. In this way, the receiving path is connected.

[0085] In some possible implementations, a second threshold can be preset in comparator 407 (the first threshold is greater than the second threshold). Comparator 407 can output a low level when the signal strength is less than the preset second threshold. Controller 408 controls switches S1 and S2 in transceiver switch 403 to open based on the low level, thus connecting the receiving path. This helps to reduce the flip frequency of the comparator output level and improve circuit stability when the received signal is unstable.

[0086] Under nine simulation conditions—combining three typical-typical corner (TT corner), slow-slow corner (SS corner), and fast-fast corner (FF corner) with two pairs of simulation conditions at room temperature, low temperature, and high temperature—the simulation was conducted on... Figure 4 Simulations were performed on the power of the signal received by the antenna in the RF circuit shown (referred to as the received signal power) and the power of the coupled signal received by the power detector (referred to as the coupled signal power). It was found that the consistency of the RF front-end device is good under different simulation conditions. Furthermore, when the received signal power is above 20 dBm, the coupled signal power still exhibits good linearity with the received signal power.

[0087] For example, please refer to Figure 5 This is a simulation diagram provided for an embodiment of this application. Figure 5As shown, curve 1 represents the relationship between coupled signal power and received signal power under typical chip angles and high-temperature conditions. Curve 2 represents the relationship between coupled signal power and received signal power under typical chip angles and normal-temperature conditions. Curve 3 represents the relationship between coupled signal power and received signal power under typical chip angles and low-temperature conditions. From curves 1, 2, and 3, it can be seen that under different simulation conditions, the coupled signal power and received signal power are basically linearly related, showing good consistency. Furthermore, even when the received signal power reaches 20 dBm, the coupled signal power and received signal power still exhibit good linearity.

[0088] In addition, under the above nine simulation conditions, Figure 4 Simulations of the received signal power and the output signal level of the power detector in the RF circuit shown reveal good consistency of the RF front-end device under different simulation conditions. Furthermore, when the first threshold is set to 120mV, the difference in the trigger threshold under different simulation conditions is only about 2dB, indicating small differences and high stability.

[0089] For example, please refer to Figure 6 This is yet another simulation diagram provided in the embodiments of this application. Figure 6 As shown, curve 4 represents the relationship between the output signal level and the received signal power under typical-typical angle conditions at high temperatures. Curve 5 represents the relationship between the output signal level and the received signal power under typical-typical angle conditions at room temperature. Curve 6 represents the relationship between the output signal level and the received signal power under typical-typical angle conditions at low temperatures. From curves 4, 5, and 6, it can be seen that the relationship between the output signal level and the received signal power is basically consistent under different simulation conditions, indicating good consistency of the RF front-end device. For example, if 120mV is set as the first threshold, the difference in the trigger threshold under different simulation conditions is only about 2dB.

[0090] This application also provides a radio frequency (RF) front-end module, including: a transceiver switch, a power amplifier, a low-noise amplifier, and any of the RF front-end devices described in the foregoing embodiments. The transceiver switch is connected to the antenna, the low-noise amplifier, and the output terminal of the control module in the RF front-end device, respectively. The output terminal of the power amplifier is coupled to the antenna, and the coupling connection point is the coupling connection point between the input terminal of the power detector in the RF front-end device and the antenna.

[0091] In some possible implementations, the RF front-end module also includes a balun. The unbalanced terminal of the balun is connected to the antenna. The balanced terminal of the balun is connected to the differential output of the power amplifier and the differential input of the power detector in the RF front-end device.

[0092] This application also provides a communication device, including: an antenna, a transceiver, and the aforementioned radio frequency front-end module. The transceiver is connected to the antenna via the radio frequency front-end module. The transceiver is used to process radio frequency signals into baseband signals or intermediate frequency signals, or to process baseband signals or intermediate frequency signals into radio frequency signals.

[0093] In some possible implementations, the communication device also includes a baseband chip. The baseband chip is connected to the transceiver. The baseband chip is used to provide baseband signals or intermediate frequency (IF) signals, or it is used to process baseband signals or IF signals.

[0094] The structure of a communication device is illustrated below as an example.

[0095] Please refer to Figure 7 This is a schematic diagram of the structure of a communication device provided in an embodiment of this application. Figure 7 As shown, the communication device may include one or more antennas 710, a radio frequency processing system 720, and a baseband processor 731.

[0096] In the downlink direction, the RF processing system 720 receives RF signals through the antenna 710 and sends the RF-processed signals to the baseband processor 731 for further processing. In the uplink direction, the baseband processor 731 processes the information from the communication device side and sends it to the RF processing system 720, which then processes the signal and transmits it through the antenna 710.

[0097] In one example, the radio frequency (RF) processing system 720 serves as the communication interface for external communication of the communication device and may include an RF front-end 721 and a transceiver 722. The RF front-end 721 can be the RF front-end or RF front-end module provided in this application embodiment. It can be used to perform shaping, passband selection, and / or gain processing on the RF (radio frequency) signal received by the antenna or the RF signal to be transmitted through the antenna, and can effectively protect the receiving path, providing high security. Exemplarily, the RF front-end 721 may include one or more components such as an RF switch, duplexer, filter, power amplifier, antenna tuner, and low-noise amplifier (not shown in the figure). The RF front-end 721 can be a circuit system composed of multiple discrete devices, or it can be integrated and packaged in one or more chips. Transceiver 722 is used to process the RF signal received by RF front-end 721 into a baseband / IF signal for further processing by baseband processor 731, and to process the baseband / IF signal provided by baseband processor 731 into an RF signal for transmission to RF front-end 721. The baseband / IF signal transmitted between transceiver 722 and baseband processor 731 can be a digital signal or an analog signal. Transceiver 722 can be implemented by one or more chips, which are typically referred to as RF chips.

[0098] In one example, the number of baseband processors 731 (also known as modem processors) can be one or more.

[0099] In one example, the baseband processor 731 can be packaged as a processor chip, such as a SoC chip or a SIP chip. In another example, the baseband processor 731 is included in a system consisting of multiple chips.

[0100] In one example, the baseband processor 731 may include one or more processor cores, memory, and interface circuitry (not shown). The one or more processor cores are used to process signals and execute one or more communication protocols. The memory is used to store at least a portion of the corresponding computer program instructions, computer programs, and / or data. In one example, the one or more processor cores implement the relevant operations provided in the embodiments of this application by executing the computer program instructions stored in the memory.

[0101] In one example, the transceiver 722 and the RF front-end 721 can also be packaged in a single chip. In another example, the transceiver 722, the RF front-end 721, and the baseband processor 731 can also be packaged in a single chip.

[0102] It should be noted that some optional features in the various embodiments of this application may not depend on other features in certain scenarios, or may be combined with other features in certain scenarios, without limitation.

[0103] The solutions in the various embodiments of this application can be used in reasonable combinations, and the explanations or descriptions of various terms, similar operations, or steps appearing in the embodiments can be referenced or explained to each other in the various embodiments, without limitation.

[0104] This application also provides a system comprising one or more of the above-mentioned radio frequency front-end devices, radio frequency front-end modules, and communication equipment.

[0105] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the explanations and beneficial effects of any of the above-mentioned radio frequency front-end modules and communication equipment can be referred to the aforementioned embodiments of radio frequency front-end devices, and will not be repeated here.

[0106] In the several embodiments provided in this application, it should be understood that the disclosed RF front-end devices, RF front-end modules, and communication devices can be implemented in other ways. For example, the structures described in the above embodiments are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or units may be combined or integrated into another system, or some features may be ignored or not executed.

[0107] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0108] Furthermore, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0109] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. 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. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A radio frequency front-end device, characterized in that, include: Power detector and control module; The input terminal of the power detector is coupled to the antenna; the antenna is also coupled to the output terminal of the power amplifier through the coupling connection; the output terminal of the power detector is connected to the input terminal of the control module; the output terminal of the control module is connected to the transceiver switch; the transceiver switch is connected to the low-noise amplifier and the antenna respectively; the power amplifier is used to process uplink signals, and the low-noise amplifier is used to process downlink signals; The power detector is used to determine the signal parameters of the coupling signal, which is the downlink signal received by the antenna coupled to the power detector. The signal parameters are used to indicate the power. The control module is used to control the downlink signal receiving path to be disconnected through the transceiver switch when the signal parameters of the coupling signal are greater than a preset first threshold.

2. The radio frequency front-end device according to claim 1, characterized in that, The control module includes a comparator and a logic module; the input terminal of the comparator is connected to the output terminal of the power detector, the output terminal of the comparator is connected to the input terminal of the logic module, and the output terminal of the logic module is connected to the transceiver switch. The comparator is used to compare the power of the coupled signal with the first threshold, and the logic module is used to control the receiving path of the downlink signal to be disconnected through the transceiver switch when the signal parameter of the coupled signal is greater than the first threshold.

3. The radio frequency front-end device according to claim 1 or 2, characterized in that, The signal parameter is voltage; the power detector is used to convert the coupled signal into a DC signal, and the voltage of the DC signal is used to indicate the power of the coupled signal.

4. The radio frequency front-end device according to any one of claims 1-3, characterized in that, When the receiving path of the downlink signal is disconnected, the downlink signal is grounded through the transceiver switch.

5. The radio frequency front-end device according to any one of claims 1-4, characterized in that, The control module is also used to control the downlink signal receiving path to be connected via the transceiver switch when the signal parameter is less than a preset second threshold; the first threshold is greater than the second threshold.

6. The radio frequency front-end device according to any one of claims 1-4, characterized in that, The control module is also used to control the downlink signal receiving path to be connected via the transceiver switch when the signal parameter is less than the first threshold.

7. The radio frequency front-end device according to any one of claims 1-6, characterized in that, The first threshold is less than or equal to the rated tolerance of the low-noise amplifier.

8. A radio frequency front-end module, characterized in that, include: Transceiver switch, power amplifier, low-noise amplifier, and the radio frequency front-end device according to any one of claims 1-7; The transceiver switch is connected to the antenna, the low-noise amplifier, and the output of the control module in the RF front-end device, respectively; the output of the power amplifier is coupled to the antenna, and the coupling connection is the coupling connection between the input of the power detector in the RF front-end device and the antenna.

9. The radio frequency front-end module according to claim 8, characterized in that, The radio frequency front-end module further includes a balun-to-unbalanced transformer; the unbalanced end of the balun-to-unbalanced transformer is connected to the antenna; the balanced end of the balun-to-unbalanced transformer is connected to the differential output of the power amplifier and the differential input of the power detector in the radio frequency front-end device.

10. A communication device, characterized in that, include: An antenna, a transceiver, and the radio frequency front-end module as described in claim 8 or 9, wherein the transceiver is connected to the antenna via the radio frequency front-end module; The transceiver is used to process radio frequency signals into baseband signals or intermediate frequency signals, or to process baseband signals or intermediate frequency signals into radio frequency signals.

11. The communication device according to claim 10, characterized in that, The communication device further includes a baseband chip; the baseband chip is connected to the transceiver; the baseband chip is used to provide the baseband signal or intermediate frequency signal, or the baseband chip is used to process the baseband signal or intermediate frequency signal.

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