T-box, relay, signal transmission system, and vehicle

Abstract

Embodiments of the present application relate to the technical field of communications, and provide a T-Box, a relay, a signal transmission system, and a vehicle, for use in implementing synchronous transmission of a radio frequency signal and a control signal to a relay by a T-Box by means of a cable. In the T-Box, a first branch comprises a vehicle to everything (V2X) circuit and a first radio frequency turn-on circuit, and the first radio frequency turn-on circuit is coupled between the V2X circuit and a first combination point. A second branch comprises a first control signal end and a first radio frequency isolation circuit, and the first radio frequency isolation circuit is coupled between the first control signal end and the first combination point; and the first control signal end outputs a control signal. In the relay, a fourth branch comprises a V2X signal end and a bidirectional switch circuit, the bidirectional switch circuit comprises a first path and a second path which are connected in parallel and coupled between the V2X signal end and a third combination point, and the first path comprises a first power amplifier. A fifth branch comprises a second control signal end coupled to the bidirectional switch circuit; and the second control signal end receives the control signal to control the gain of the first power amplifier.

Description

T-Box, relay, signal transmission system and vehicle

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on June 13, 2023, with application number 202310704285.6 and application name “T-Box, Relay, Signal Transmission System and Vehicle”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a T-Box, a relay, a signal transmission system and a vehicle. Background Art

[0003] The vehicle-to-everything (V2X) system is a next-generation information and communication technology that connects vehicles with everything. Vehicles rely on V2X-enabled telematics boxes (T-Boxes) as transmitters and receivers of V2X information. These devices, leveraging mature communication network architectures, can form a V2X system with other things, enabling V2X communication.

[0004] Because the vehicle's external antenna is far from the T-Box, and higher frequencies increase RF signal attenuation, excessive attenuation can severely degrade the vehicle's RF performance. To mitigate this attenuation, technicians in this field have proposed using a relay. A relay amplifies and forwards the signal, increasing RF signal transmission capacity.

[0005] However, with current technology, the T-Box cannot send control signals to the relay, resulting in the relay having no dynamic adjustment capabilities, such as the ability to dynamically adjust the gain, which in turn causes the signal transmission system composed of the T-Box and the relay to be unable to dynamically match different vehicle models.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a T-Box, a relay, a signal transmission system, and a vehicle, for enabling the T-Box to synchronously send radio frequency signals and control signals to the relay via a cable.

[0008] To achieve the above objectives, this application adopts the following technical solutions:

[0009] In a first aspect of an embodiment of the present application, a T-Box is provided. The T-Box includes a first branch and a second branch. The first branch includes a vehicle-to-everything (V2X) circuit and a first radio frequency (RF) conduction circuit, coupled between the V2X circuit and a first junction point. The V2X circuit is configured to transmit RF signals when the T-Box is transmitting signals and receive RF signals when the T-Box is receiving signals. The second branch includes a first control signal terminal and a first RF isolation circuit, coupled between the first control signal terminal and the first junction point. The first control signal terminal is configured to output a control signal. The first RF conduction circuit is configured to pass RF signals and isolate control signals, and the first RF isolation circuit is configured to pass control signals and isolate RF signals.

[0010] In the T-Box provided in the embodiment of the present application, the RF signal transmitted by the first branch is used for V2X communication, and the control signal transmitted by the second branch is used to control the relay. The control signal can carry any information related to controlling the relay. The embodiment of the present application uses a circuit structure to aggregate the control signal with the RF signal, so that the T-Box can simultaneously output the control signal when outputting the RF signal. The control signal can be used to control the relay to adjust parameters such as gain. When the T-Box is applied to a signal transmission system, the T-Box can simultaneously transmit the RF signal and the control signal to the relay through a cable. This does not increase the complexity of the signal transmission system excessively, but allows the relay to dynamically adjust its own parameters according to the control signal to match different vehicle models. Moreover, simulations have found that while the control signal is transmitted simultaneously, the loss of the RF signal transmitted by the V2X circuit is low, which has almost no impact on the RF performance of the T-Box. In addition, the embodiment of the present application achieves the aggregation of the control signal and the RF signal through the T-Box itself, and realizes the synchronous transmission of the control signal and the RF signal through a single cable through a hardware circuit solution. This eliminates the need for additional large-scale components, reduces costs, meets the requirements of miniaturization, and is suitable for use in vehicles. For example, a control signal can carry information related to adjusting relay gain, allowing it to adapt to different cable attenuation according to different application scenarios, allowing a single signal transmission system to adapt to a variety of vehicle models. Alternatively, a control signal can carry information related to informing the relay of signal transmission and reception, allowing it to adjust transmission and reception according to different application states.

[0011] In one possible implementation, the first RF isolation circuit includes a (1 / 4 + N / 2)λ transmission line; a first end of the (1 / 4 + N / 2)λ transmission line is coupled to a first junction point, a second end of the (1 / 4 + N / 2)λ transmission line is coupled to a first node, and the first node is coupled to a first control signal terminal; where λ is the wavelength of the RF signal, and N is an integer greater than or equal to 0. Isolating multiple RF signals using the transmission line has a simple structure and occupies a small area.

[0012] In one possible implementation, the T-Box further includes a circuit board, and the (1 / 4+N / 2)λ transmission line is integrated inside the circuit board. This reduces the footprint of the T-Box and reduces the cost.

[0013] In one possible implementation, the first RF isolation circuit further includes a first capacitor and a second capacitor; a first end of the first capacitor and a first end of the second capacitor are both coupled to a reference ground voltage terminal, and a second end of the first capacitor and a second end of the second capacitor are both coupled to a first node. By providing the first and second capacitors, frequency band deviation caused by machining errors of the (1 / 4+N / 2)λ transmission line can be compensated for, thereby optimizing the isolation effect on RF signals.

[0014] In one possible implementation, the first radio frequency isolation circuit includes an isolator. In this way, the first radio frequency isolation circuit is a finished device that can be directly coupled to the T-Box, simplifying the design.

[0015] In one possible implementation, the T-Box also includes a third branch; the third branch includes a first power circuit, which is coupled to a second combining point, which is located between the first RF isolation circuit and the first control signal terminal. The signals aggregated at the first combining point then include RF signals, control signals, and power current. This hardware circuit solution allows a single cable to simultaneously transmit RF signals, control signals, and power current without the need for additional large-scale components, demonstrating significant market potential.

[0016] In a possible implementation, the first branch further includes a first AC conduction and DC isolation circuit, and the first AC conduction and DC isolation circuit are coupled in series with the first RF conduction circuit between the V2X circuit and the first junction point.

[0017] By providing a first AC-DC blocking circuit in the first branch, the RF signal can pass through the first AC-DC blocking circuit. However, the power supply current at the first junction cannot be transmitted to the V2X circuit through the first AC-DC blocking circuit. This reduces power supply current loss and mitigates interference with the RF signal transmitted by the first branch.

[0018] In a possible implementation, the first AC-passing and DC-isolating circuit includes a first DC-isolating capacitor. In this way, the structure of the first AC-passing and DC-isolating circuit is simple, and the area occupied by the T-Box is small.

[0019] In a possible implementation, the second branch further includes a second AC-passing and DC-isolating circuit, and the second AC-passing and DC-isolating circuit is coupled between the first control signal terminal and the second combining point.

[0020] By providing a second AC-passing and DC-blocking circuit in the second branch, the power supply current can be prevented from being transmitted in the second branch. In other words, the power supply current is not transmitted to the first control signal terminal. This can reduce power supply current loss and mitigate interference with the control signal transmitted by the second branch.

[0021] In a possible implementation, the second AC-passing and DC-isolating circuit includes a second DC-isolating capacitor. In this way, the structure of the second AC-passing and DC-isolating circuit is simple, and the area occupied by the T-Box is small.

[0022] In a possible implementation, the third branch further includes a first DC-passing and AC-isolating circuit, and the first DC-passing and AC-isolating circuit is coupled between the first power supply circuit and the second junction.

[0023] The power current output by the first power supply circuit in the third branch is transmitted to the first combining point, but this power current is isolated by the first AC-passing and DC-isolating circuit and prevents it from being transmitted to the first branch. Simultaneously, the power current is isolated by the second AC-passing and DC-isolating circuit and prevents it from being transmitted to the second branch, resulting in virtually no power current loss. The first DC-passing and AC-isolating circuit also isolates the control signal in the second branch, reducing control signal loss.

[0024] In a possible implementation, the first DC-passing and AC-isolating circuit includes an equivalent inductor. In this way, the structure of the first DC-passing and AC-isolating circuit is simple, and the area occupied by the T-Box is small.

[0025] In one possible implementation, the first control signal terminal includes a first gain control signal terminal and a first transceiver control signal terminal. In this way, the T-Box can synchronously transmit the gain control signal and the transceiver control signal to the relay, thereby optimizing the performance of the T-Box.

[0026] In one possible implementation, the second branch further includes a first controller configured to, upon receiving a transceiver control signal from the first transceiver control signal terminal, output a first gain control signal to the first gain control signal terminal. The first controller may output the first gain control signal based on the transceiver control signal to control a gain value of the relay.

[0027] In one possible implementation, a first controller is coupled to a first gain control signal terminal and a first transceiver control signal terminal, and a V2X circuit is coupled to the first transceiver control signal terminal. The first controller transmits the first gain control signal, and the first gain control signal is adjustable to suit different application scenarios.

[0028] In one possible implementation, the second branch further includes a modulation circuit; the modulation circuit's input is coupled to the first gain control signal terminal and the first transceiver control signal terminal, and the modulation circuit's output is coupled to the first RF isolation circuit. This allows one signal to carry multiple pieces of information, simplifying the T-Box's structure and optimizing its performance.

[0029] In one possible implementation, the second branch further includes a carrier circuit configured to output a carrier signal; the carrier circuit is coupled to an input terminal of the modulation circuit. By providing the carrier signal to carry the control signal for transmission, the control signal transmission is facilitated, thereby improving the transmission efficiency of the control signal.

[0030] In one possible implementation, the carrier circuit includes a clock oscillator. Using a clock signal as the carrier signal can easily separate the clock signal from the control signal after receiving the modulated signal, and data is not easily lost during separation.

[0031] In one possible implementation, the modulation circuit includes a first AND gate; the input of the first AND gate is coupled to the first gain control signal terminal, the first transceiver control signal terminal, and the carrier circuit, and the output of the first AND gate is coupled to the first RF isolation circuit. Using three AND gates to modulate three signals has a simple structure and occupies a small area.

[0032] In one possible implementation, the modulation circuit includes a second AND gate and a third AND gate. The input of the second AND gate is coupled to two of the first gain control signal terminal, the first transceiver control signal terminal, and the carrier circuit, and the output of the second AND gate is coupled to the input of the third AND gate. The input of the third AND gate is also coupled to the first gain control signal terminal, the first transceiver control signal terminal, and the remaining one of the carrier circuit, and the output of the third AND gate is coupled to the first RF isolation circuit. Using a two-stage dual AND gate approach to modulate three signals is simple in principle.

[0033] In one possible implementation, the second branch further includes an operational amplifier coupled between the modulation circuit and the first RF isolation circuit. By providing an operational amplifier at the output of the modulation circuit, the modulated signal of the modulation circuit can be amplified or attenuated before being transmitted to the first summing point, thereby meeting the needs of various application scenarios.

[0034] In one possible implementation, the first radio frequency conduction circuit includes a bandpass filter, which is a simple structure, mature technology, and low cost implementation.

[0035] According to a second aspect of an embodiment of the present application, a relay is provided, comprising a fourth branch and a fifth branch. The fourth branch comprises a vehicle-to-anything (V2X) signal terminal and a bidirectional switch circuit, wherein the bidirectional switch circuit comprises a first path and a second path coupled in parallel between the V2X signal terminal and a third junction, wherein the first path comprises a first power amplifier, wherein the output of the first power amplifier is coupled to the V2X signal terminal; the V2X signal terminal is configured to transmit a radio frequency signal when the relay is configured to transmit a signal, and to receive a radio frequency signal when the relay is configured to receive a signal; and the fifth branch comprises a second control signal terminal and a second radio frequency isolation circuit, wherein the second control signal terminal is coupled to the bidirectional switch circuit; the second radio frequency isolation circuit is coupled between the second control signal terminal and the third junction; the second control signal terminal is configured to receive a control signal; and the second radio frequency isolation circuit is configured to pass the control signal and isolate the radio frequency signal.

[0036] The relay provided in the embodiments of the present application receives the control signal sent by the T-Box and adjusts the relay itself in combination with the control signal, making the relay dynamically adjustable to meet the needs of different application scenarios. When the control signal includes a first gain control signal, the relay can adjust its own gain value in combination with the first gain control signal to adapt to the line loss in different vehicles. In this way, a single signal transmission system can be adapted to different types of vehicles, with extremely high adaptability and low cost.

[0037] In one possible implementation, the second control signal terminal includes a second gain control signal terminal and a second transceiver control signal terminal; the second gain control signal terminal is coupled to the first power amplifier, and the second transceiver control signal terminal is coupled to the first path and the second path, respectively. In this way, the relay can recognize signals including the gain control signal and the transceiver control signal and be controlled by these signals to optimize relay performance.

[0038] In one possible implementation, the fifth branch further includes a second controller and a first frequency band blocking circuit; the first frequency band blocking circuit is coupled between the second transceiver control signal terminal and the second node, and the second node is coupled to the second RF isolation circuit; the second controller is configured to, upon receiving the transceiver control signal from the second transceiver control signal terminal and the control signal from the second node, output a second gain control signal to the second gain control signal terminal. The second controller generates a second gain control signal based on a control signal transmitted by the T-BOX containing the first gain control signal and the separated transceiver control signal, and transmits the second gain control signal to the first power amplifier to control the gain of the first power amplifier.

[0039] In one possible implementation, the output of the second controller is coupled to the second gain control signal terminal, and the input of the second controller is coupled to the second transceiver control signal terminal and the second node. This method separates the modulated signal output by the T-Box, has a simple structure, and minimizes signal loss.

[0040] In one possible implementation, the fifth branch further includes a second frequency band blocking circuit coupled between the second node and the second RF isolation circuit. If the modulated signal includes a carrier signal, the relay may first block the carrier signal, thereby simplifying the separation of the modulated signal.

[0041] In one possible implementation, the fifth branch further includes a first signal enhancement circuit coupled between the second controller and the second node. By providing the first signal enhancement circuit between the second controller and the second node, the signal from the second node can be enhanced before being transmitted to the second controller, thereby improving signal processing accuracy.

[0042] In one possible implementation, the fifth branch further includes a second signal enhancement circuit coupled between the second controller and the second transceiver control signal terminal. By providing the second signal enhancement circuit between the second controller and the second transceiver control signal terminal, the signal from the second transceiver control signal terminal can be enhanced before being transmitted to the second controller, thereby improving signal accuracy.

[0043] In one possible implementation, the fifth branch further includes a third signal enhancement circuit coupled between the second node and the second RF isolation circuit. By providing the second signal enhancement circuit between the second node and the second RF isolation circuit, the signal output by the second RF isolation circuit can be enhanced before being transmitted to the second node, thereby improving signal accuracy.

[0044] In one possible implementation, the relay also includes a power detector, which is coupled to the input end and the third junction of the second controller respectively, and the second controller is further configured to receive the power signal sent by the power detector before outputting the second gain control signal to the second gain control signal end. The second controller outputs a second gain control signal based on the first gain control signal (characterizing the power intensity of the RF signal output by the T-Box) and the power signal output by the power detector (characterizing the power intensity of the RF signal after the cable loss) to perform corresponding gain control on the first power amplifier. The gain value of the second gain control signal output by the second controller is different for different cable lengths, so that the signal transmission system has the function of adaptively adapting to different cable lengths, so that the signal transmission system provided in the embodiment of the present application can be applicable to vehicles with cables of various lengths.

[0045] In one possible implementation, the second RF isolation circuit includes a (1 / 4 + N / 2)λ transmission line; a first end of the (1 / 4 + N / 2)λ transmission line is coupled to a third junction point, a second end of the (1 / 4 + N / 2)λ transmission line is coupled to a third node, and the third node is coupled to the second control signal terminal; where λ is the wavelength of the RF signal, and N is an integer greater than or equal to 0. Isolating multiple RF signals using the transmission line has a simple structure and occupies a small area.

[0046] In one possible implementation, the relay further includes a circuit board, and the (1 / 4+N / 2)λ transmission line is integrated into the circuit board. In this way, the relay occupies a small area and has a low cost.

[0047] In one possible implementation, the second RF isolation circuit further includes a third capacitor and a fourth capacitor; a first end of the third capacitor and a first end of the fourth capacitor are both coupled to the reference ground voltage terminal, and a second end of the third capacitor and a second end of the fourth capacitor are both coupled to a third node. By providing the third and fourth capacitors, frequency band deviation caused by machining errors of the (1 / 4+N / 2)λ transmission line can be compensated, thereby optimizing the isolation effect on RF signals.

[0048] In a possible implementation, the second path includes a second power amplifier that can amplify the signal transmitted by the second path to meet different requirements.

[0049] In one possible implementation, the relay further includes a sixth branch; the sixth branch includes a second power circuit, which is coupled to a fourth junction point, located between the second RF isolation circuit and the second control signal terminal. The relay includes the sixth branch, which can receive power current sent by the T-Box to power the relay, resulting in a simple structure and low cost.

[0050] In one possible implementation, the fourth branch further includes a second RF conduction circuit coupled between the bidirectional switch circuit and the third junction. The second RF conduction circuit in the fourth branch can filter out signals in other frequency bands and pass the RF signal to reduce interference from out-of-band signals.

[0051] In one possible implementation, the fourth branch further includes a third AC-passing and DC-blocking circuit coupled between the bidirectional switch circuit and the third junction. The third AC-passing and DC-blocking circuit can reduce power supply current loss and mitigate interference with radio frequency signals transmitted by the fourth branch.

[0052] In a possible implementation, the third AC-passing and DC-isolating circuit includes a third DC-isolating capacitor. In this way, the structure of the third AC-passing and DC-isolating circuit is simple, and the area occupied by the relay is small.

[0053] In one possible implementation, the fifth branch further includes a fourth AC-passing and DC-isolating circuit coupled between the second control signal terminal and the fourth junction. The fourth AC-passing and DC-isolating circuit can reduce power supply current loss and mitigate interference with the control signal transmitted by the fifth branch.

[0054] In a possible implementation, the fourth AC-passing and DC-isolating circuit includes a fourth DC-isolating capacitor. In this way, the structure of the fourth AC-passing and DC-isolating circuit is simple, and the area occupied by the relay is small.

[0055] In one possible implementation, the sixth branch further includes a second direct-current isolation circuit coupled between the second power supply circuit and the fourth junction. The second direct-current isolation circuit can isolate the control signal in the fifth branch, thereby reducing control signal loss.

[0056] In a possible implementation, the second DC-passing and AC-isolating circuit includes an equivalent inductor. In this way, the structure of the second DC-passing and AC-isolating circuit is simple, and the area occupied by the relay is small.

[0057] A third aspect of the embodiments of the present application provides a signal transmission system, comprising the T-Box according to any one of the first aspects, a cable, and the relay according to any one of the second aspects; one end of the cable is coupled to the first combining point of the T-Box, and the other end of the cable is coupled to the third combining point of the relay. The system provided by the embodiments of the present application includes the T-Box according to the first aspect and the relay according to the second aspect, and its beneficial effects are the same as those of the T-Box and the relay, and are not further described here.

[0058] According to a fourth aspect of an embodiment of the present application, a vehicle is provided, comprising an antenna and the signal transmission system according to the third aspect, wherein the signal transmission system is coupled to the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] FIG1 is a schematic diagram of a V2X application scenario provided by an embodiment of the present application;

[0060] FIG2 is a framework diagram of a vehicle provided in an embodiment of the present application;

[0061] Figures 3 to 6 are schematic diagrams of a T-Box framework provided in an embodiment of the present application;

[0062] FIG7A is an architecture diagram of a transmission line network provided in an embodiment of the present application;

[0063] FIG7B is a simulation diagram of the isolation effect of the first RF isolation circuit shown in FIG6 on the RF signal provided by an embodiment of the present application;

[0064] FIG7C is a simulation diagram of the isolation effect of the first RF isolation circuit shown in FIG6 on RF signals provided by another embodiment of the present application;

[0065] Figures 8 to 12 are schematic diagrams of a T-Box framework provided in an embodiment of the present application;

[0066] FIG13 is a diagram showing a modulation result of a modulation circuit provided in an embodiment of the present application;

[0067] Figures 14-20 are schematic diagrams of a relay framework provided in an embodiment of the present application. DETAILED DESCRIPTION

[0068] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0069] Hereinafter, the terms "second," "first," etc., are used for descriptive convenience only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature qualified as "second," "first," etc., may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0070] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left", and "right" may be defined including but not limited to the orientation relative to the schematic placement of the components in the drawings. It should be understood that these directional terms may be relative concepts, which are used for relative descriptions and clarifications, and may change accordingly according to changes in the orientation of the components in the drawings.

[0071] In the embodiments of this application, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, "connection" can mean fixed connection, detachable connection, or integration; it can mean direct connection or indirect connection through an intermediate medium. In addition, the term "coupling" can mean direct electrical connection or indirect electrical connection through an intermediate medium. The term "contact" can mean direct contact or indirect contact through an intermediate medium.

[0072] In the embodiments of the present application, "and / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0073] First, to facilitate understanding, the following introduces relevant terms and concepts that may be involved in the embodiments of the present application.

[0074] (1) Vehicle to everything (V2X)

[0075] V2X (vehicle-to-everything) (V2X) enables vehicles to exchange information with all entities that may affect them, thereby reducing accidents, alleviating traffic congestion, lowering environmental pollution, and providing other information services. As shown in Figure 1, V2X consists of four components: Vehicle-to-Network (V2N) communication is currently the most widely used form of connected vehicle technology. Its primary function is to connect vehicles to cloud servers via mobile networks, enabling them to access navigation, entertainment, anti-theft, and other cloud-based applications. Vehicle-to-vehicle (V2V) communication can be used for information exchange and alerts between vehicles, with the most typical application being vehicle-to-vehicle collision avoidance safety systems. Vehicle-to-infrastructure (V2I) communication allows vehicles to communicate with roads and even other infrastructure, such as traffic lights and roadblocks, to obtain road management information such as traffic light signal timing. Vehicle-to-pedestrian (V2P) communication is used to provide safety warnings to pedestrians and non-motorized vehicles on the road.

[0076] Currently, V2X technology can be the dedicated short-range communication (DSRC) for automobiles defined in IEEE 802.11p, or the cellular vehicle-to-everything (C-V2X) technology based on cellular mobile communication technology defined by the 3rd Generation Partnership Project (3GPP). It should be understood that the application scenarios of the solutions provided in the embodiments of the present application are not limited to the above two mainstream implementations (DSRC and C-V2X) in the current V2X technology. As technology evolves, other emerging V2X technology implementations will not exceed the scope of application scenarios covered by the embodiments of the present application.

[0077] Considering the current state of the network and the technological advantages of C-V2X evolution, C-V2X should be the preferred V2X technology standard in China. C-V2X can be categorized into two communication modes based on the interface: direct (V2X-direct) and cellular (V2X-cellular). V2X-direct, based on the D2D (device-to-device) Proximity Service (ProSe) in the LTE standard, uses the PC5 interface and a dedicated V2X frequency band (specified as B47 5.9GHz) to enable direct communication between vehicles, roads, and people. This provides low latency and supports high mobile speeds, but requires effective resource allocation and congestion control algorithms. Direct communication between neighboring devices is possible in environments without LTE network coverage. V2X-cellular utilizes LTE broadcasts, forwarded via the cellular network's UU interface, and uses cellular frequency bands (specified as B3, B7, B8, B39, and B41).

[0078] Vehicles, powered by V2X technology, share information across communication channels, expanding their perception range to detect hidden threats and ensure that important warnings are delivered promptly and accurately at critical moments. V2X technology not only improves vehicle safety and enhances road traffic efficiency, but also drives the development of autonomous driving technology.

[0079] (2) In-vehicle communication terminal (telematics box, T-Box)

[0080] The vehicle-mounted T-Box is a communication component (or device) in the vehicle information system. The vehicle-mounted T-Box is mainly used to communicate with other devices and / or other electronic devices in the vehicle, enabling the use of electronic devices to display vehicle information and control the vehicle. This component is pre-installed in the vehicle, accessing the mobile operator network through a built-in communication module, connecting to the vehicle body network through the vehicle bus, connecting to the vehicle computer through data channels such as Ethernet / wireless fidelity (Wi-Fi) / universal serial bus (USB) interface, and sharing mobile data with the driver and passengers in the vehicle through the vehicle computer Wi-Fi.

[0081] FIG2 is a framework diagram of a vehicle provided in an embodiment of the present application.

[0082] As shown in FIG2 , an embodiment of the present application provides a vehicle 100 , which includes a T-Box, a cable, a relay, and an antenna.

[0083] The T-Box is coupled to the antenna via a cable. The V2X circuit in the T-Box transmits radio frequency signals, which are then transmitted between the T-Box and the antenna. Since the T-Box is typically front-mounted in the vehicle 100, while the antenna is typically rear-mounted, the distance between the T-Box and the antenna is typically quite large. The higher the frequency, the greater the attenuation of the radio frequency signal. Excessive attenuation can severely degrade the vehicle's radio frequency performance.

[0084] Based on this, as shown in FIG2 , a relay is added to the vehicle 100 . The relay is located between the T-Box and the antenna. The relay amplifies and forwards the RF signal, thereby increasing the transmission capacity of the RF signal and weakening the attenuation of the RF signal.

[0085] The T-Box, cables, and relays constitute a signal transmission system, which is coupled to the antenna to enable the vehicle 100 to implement the V2X function.

[0086] However, since a T-Box needs to be adapted to multiple vehicle models, the antenna and relay positions of each vehicle model are different, and the gain of the relay for the RF signal will also be different.

[0087] In order to solve the above problems, those skilled in the art have designed multiple relays with different gain values ​​to adapt to cables of different lengths, and fixed the gain of the relays to adapt to different cable attenuations without recharging.

[0088] The gain value of the relay is fixed, and different models use relays with different configurations. Although this can meet the needs, the adaptation solution is complex, and each model needs to develop adaptation software separately, which will increase costs.

[0089] Based on this, an embodiment of the present application provides a signal transmission system, comprising a T-Box, a cable, and a relay. One end of the cable is coupled to the T-Box, and the other end of the cable is coupled to the relay. By modifying the structure of the T-Box and the relay, the signal transmitted in the cable includes a gain control signal. In this case, the relay is a gain-adjustable relay, allowing the same signal transmission system to adapt to different vehicles 100.

[0090] Below, the T-Box and the relay in the signal transmission system are schematically described respectively, and then the signal transmission system is schematically described.

[0091] Example 1

[0092] FIG3 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0093] An embodiment of the present application provides a T-Box, as shown in FIG3 , wherein the T-Box includes a first branch 1 and a second branch 2 .

[0094] The first branch 1 includes a V2X circuit 61 and a first RF conduction circuit 11 . The first RF conduction circuit 11 is coupled between the V2X circuit 61 and a first junction point Q1 .

[0095] The V2X circuit 61 is used to transmit and receive radio frequency signals. The V2X circuit 61 can be used to receive radio frequency signals, and the V2X circuit 61 can also be used to transmit radio frequency signals. For example, the radio frequency signal is a 5.9 GHz signal. Of course, the radio frequency signal can be a signal of any frequency band transmitted by the V2X circuit 61. 5.9 GHz is only an example.

[0096] When the T-Box transmits a signal, the V2X circuit 61 outputs a radio frequency signal, which is then transmitted to the first combiner Q1 via the first radio frequency conduction circuit 11. When the T-Box receives a signal, the V2X circuit 61 receives a radio frequency signal, which is then transmitted to the V2X circuit 61 via the first combiner Q1 via the first radio frequency conduction circuit 11.

[0097] It can also be understood that the signal transmitted in the first branch 1 is a radio frequency signal, and the radio frequency signal can be transmitted from the V2X circuit 61 to the first combining point Q1, and the radio frequency signal can also be transmitted from the first combining point Q1 to the V2X circuit 61.

[0098] The embodiment of the present application does not limit the structure of the V2X circuit 61, and the V2X circuits (also called V2X modules) in related technologies are applicable to the embodiment of the present application.

[0099] The second branch 2 includes a first control signal terminal M1 and a first RF isolation circuit 21 . The first RF isolation circuit 21 is coupled between the first control signal terminal M1 and the first junction Q1 .

[0100] The first control signal terminal M1 is used to output control signals, such as a first gain control signal and a transceiver control signal. When the distance between the T-Box and the antenna varies, the control signal can control the relay's gain to adjust the relay's gain based on specific scenarios.

[0101] It can also be understood that what is transmitted in the second branch 2 is a control signal, and the control signal can be transmitted from the first control signal terminal M1 to the first combining point Q1.

[0102] The radio frequency signal and the control signal are combined at the first combining point Q1 and then output to the cable. Therefore, the signal transmitted in the cable includes at least the radio frequency signal and the control signal.

[0103] Then, when the T-Box is used to transmit signals, the RF signal transmitted by the first branch 1 and the control signal transmitted by the second branch 2 are combined at the first combining point Q1 and then output. When the T-Box is used to receive signals, the first combining point Q1 receives the RF signal and then branches the RF signal to the first branch 1.

[0104] In some embodiments, the RF signal and the control signal have different frequencies.

[0105] For example, the radio frequency signal is a high-frequency signal, and the control signal is a low-frequency signal.

[0106] In some embodiments, to prevent signals on the first branch 1 and the second branch 2 from interfering with each other, the first RF conduction circuit 11 in the first branch 1 is configured to pass RF signals and isolate control signals. The first RF isolation circuit 21 in the second branch 2 is configured to pass control signals and isolate RF signals.

[0107] That is, based on the T-Box shown in Figure 3, when the T-Box is used to send signals:

[0108] The RF signal output by the V2X circuit 61 in the first branch 1 is transmitted to the first combining point Q1 via the first RF conduction circuit 11. However, the RF signal is isolated by the first RF isolation circuit 21 and is hardly transmitted to the first control signal terminal M1, resulting in almost no RF signal loss.

[0109] In the second branch 2, the control signal output by the first control signal terminal M1 is transmitted to the first combining point Q1 via the first RF isolation circuit 21. However, the control signal is isolated by the first RF conduction circuit 11 and is hardly transmitted to the V2X circuit 61, resulting in almost no loss of the control signal.

[0110] When the T-Box is used to receive signals:

[0111] The signal received by the first combining point Q1 includes a radio frequency signal.

[0112] The RF signal in the first combining point Q1 is isolated by the first RF isolation circuit 21 and is hardly transmitted to the first control signal terminal M1. However, the RF signal can be transmitted to the V2X circuit 61 through the first RF conduction circuit 11 to separate the RF signal into the first branch 1.

[0113] The control signal in the first combining point Q1 is isolated by the first RF conduction circuit 11 and will not be transmitted to the V2X signal end, but the control signal can be transmitted to the first control signal end M1 through the first RF isolation circuit 21 to separate the control signal in the aggregated signal to the second branch 2.

[0114] In the embodiment of the present application, the first combining point Q1 may be coupled to the signal output end of the T-Box, or the first combining point Q1 may serve as the signal output end of the T-Box.

[0115] In some embodiments, as shown in FIG. 3 , the T-Box further includes a connector 80 , the T-Box is coupled to the cable via the connector 80 , and the first junction point Q1 is coupled to the connector 80 .

[0116] In the T-Box provided in the embodiment of the present application, the RF signal transmitted by the first branch 1 is used for V2X communication, and the control signal transmitted by the second branch 2 is used to control the relay. The control signal can carry any information related to controlling the relay. The embodiment of the present application aggregates the control signal with the RF signal, so that the T-Box can simultaneously output the control signal when outputting the RF signal. The control signal can be used to control the relay to adjust parameters such as gain. When the T-Box is applied to a signal transmission system, the T-Box can simultaneously transmit the RF signal and the control signal to the relay through a cable, without excessively increasing the complexity of the signal transmission system, but allowing the relay to dynamically adjust its own parameters according to the control signal to match different vehicle models. Moreover, simulations have found that while synchronously transmitting the control signal, the loss of the RF signal transmitted by the V2X circuit 61 is low, and the RF performance is hardly affected. In addition, the embodiment of the present application achieves the aggregation of the control signal and the RF signal through the T-Box itself, and realizes the synchronous transmission of the control signal and the RF signal through a single cable through a hardware circuit solution. This eliminates the need for additional large-scale components, reduces costs, meets the requirements of miniaturization, and can be applied to vehicles. For example, the control signal can carry information related to adjusting relay gain to adapt to different cable attenuation according to different application scenarios, allowing a single signal transmission system to adapt to a variety of vehicle models. And / or, the control signal can carry information related to instructing the relay to transmit and receive signals, adjusting the relay's transmission and reception according to different application states.

[0117] FIG4 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0118] In some embodiments, as shown in FIG4 , the T-Box further includes a third branch 3 .

[0119] The third branch 3 includes a first power circuit 63 . The first power circuit 63 is coupled to a second junction point Q2 . The second junction point Q2 is located between the first RF isolation circuit 21 and the first control signal terminal M1 .

[0120] The first power supply circuit 63 is used to transmit DC power. The first power supply circuit 63 can supply power to the T-Box. The first power supply circuit 63 can also transmit the DC power to the relay through a cable to power the relay.

[0121] It can also be understood that the third branch 3 transmits power current, which is transmitted from the first power circuit 63 to the second junction point Q2 and then to the first junction point Q1.

[0122] Then, the signals aggregated in the first combining point Q1 include RF signals, control signals and power supply current. Through the hardware circuit solution, one cable can synchronously transmit RF signals, control signals and power supply current without the need to introduce additional large-size devices, which has great market prospects.

[0123] The first power supply circuit 63 is used to provide a direct current of 1A, for example. The embodiment of the present application does not limit the structure of the first power supply circuit 63. Circuits used to provide direct current in related technologies are applicable to the embodiment of the present application.

[0124] In some embodiments, please continue to refer to FIG. 4 , the third branch 3 further includes a first DC-passing and AC-isolating circuit 31 , and the first DC-passing and AC-isolating circuit 31 is coupled between the first power circuit 63 and the second junction Q2 .

[0125] Since both the RF signal and the control signal are AC signals, by providing the first DC-blocking and AC-blocking circuit 31 on the third branch 3, the DC power output by the first power supply circuit 63 can be transmitted to the second combining point Q2 and then to the first combining point Q1 via the first DC-blocking and AC-blocking circuit 31. However, the RF signal transmitted by the first branch 1 and the control signal transmitted by the second branch 2 cannot be transmitted to the first power supply circuit 63 via the first DC-blocking and AC-blocking circuit 31.

[0126] In this way, the loss of RF signals and control signals can be reduced.

[0127] In some embodiments, please continue to refer to Figure 4, the first branch 1 also includes a first AC-passing and DC-blocking circuit 41, and the first AC-passing and DC-blocking circuit 41 and the first RF conduction circuit 11 are coupled in series between the V2X circuit 61 and the first junction Q1.

[0128] In Figure 4, the first RF conduction circuit 11 is coupled close to the V2X circuit 61, and the first AC-passing and DC-blocking circuit 41 is coupled close to the first junction Q1 as an example. The first RF conduction circuit 11 can also be coupled close to the first junction Q1, and the first AC-passing and DC-blocking circuit 41 is coupled close to the V2X circuit 61.

[0129] By providing the first AC-DC blocking circuit 41 in the first branch 1, the RF signal can pass through the first AC-DC blocking circuit 41. However, the power current at the first junction Q1 (for example, the power current transmitted from the first power circuit 63 to the first junction Q1) cannot be transmitted to the V2X circuit 61 through the first AC-DC blocking circuit 41. This can reduce power current loss and mitigate interference with the RF signal transmitted by the first branch 1.

[0130] In some embodiments, please continue to refer to FIG. 4 , the second branch 2 further includes a second AC-passing and DC-isolating circuit 51 , and the second AC-passing and DC-isolating circuit 51 is coupled between the first control signal terminal M1 and the second junction Q2 .

[0131] That is, the second AC-passing and DC-blocking circuit 51 is coupled to the end of the first RF isolation circuit 21 away from the first junction Q1 .

[0132] The first combining point Q1 aggregates three signals: radio frequency signal, control signal and power supply current. The radio frequency signal can be transmitted in the first branch 1. However, in order to reduce the loss of the radio frequency signal, it is not desired for the radio frequency signal to be transmitted in the second branch 2 and the third branch 3. The first radio frequency isolation circuit 21 is coupled between the first combining point Q1 and the second combining point Q2. The radio frequency signal at the first combining point Q1 cannot be transmitted to the second combining point Q2, but the power supply current will be transmitted to the second combining point Q2. Therefore, by setting a second AC-DC isolation circuit 51 in the second branch 2, the power supply current can be prevented from being transmitted in the second branch 2. In other words, the power supply current will not be transmitted to the first control signal terminal M1. On the one hand, the loss of the power supply current can be reduced, and on the other hand, the interference caused to the control signal transmitted by the second branch 2 can be weakened.

[0133] Based on the circuit structure shown in Figure 4, when the T-Box is used to send signals:

[0134] In the first branch 1, the RF signal output by the V2X circuit 61 is transmitted to the first combining point Q1, but the RF signal is isolated by the first RF isolation circuit 21 and will not be transmitted to the second branch 2 and the third branch 3, resulting in almost no RF signal loss.

[0135] In the second branch 2, the control signal output by the first control signal terminal M1 is transmitted to the first combining point Q1, but the control signal is isolated by the first RF conduction circuit 11 and is not transmitted to the first branch 1. At the same time, the control signal is isolated by the first DC-passing and AC-isolating circuit 31 and is not transmitted to the third branch 3, resulting in almost no control signal loss.

[0136] In the third branch 3, the power current output by the first power supply circuit 63 is transmitted to the first junction Q1. However, the power current is isolated by the first AC-passing and DC-isolating circuit 41 and is not transmitted to the first branch 1. Simultaneously, the power current is isolated by the second AC-passing and DC-isolating circuit 51 and is not transmitted to the second branch 2, resulting in virtually no power current loss.

[0137] When the T-Box is used to receive signals:

[0138] The aggregate signal received by the first combining point Q1 includes a radio frequency signal.

[0139] The RF signal in the first combining point Q1 is isolated by the first RF isolation circuit 21 and will not be transmitted to the second branch 2 and the third branch 3, but the RF signal can be transmitted to the V2X circuit 61 through the first RF conduction circuit 11 to achieve the transmission of the RF signal in the first branch 1.

[0140] It should be explained here that the first DC-passing and AC-isolating circuit 31, the first AC-passing and DC-isolating circuit 41, and the second AC-passing and DC-isolating circuit 51 in the T-Box shown in Figure 4 are presented with dotted lines, indicating that the T-Box provided in the embodiment of the present application may not include the above three circuit modules, or may only include one or two of the above three circuit modules, and is not limited to that the T-Box must include all of the above three circuit modules.

[0141] FIG5 and FIG6 are schematic diagrams of a topological structure of a T-Box provided in an embodiment of the present application.

[0142] Based on the above T-Box architecture, as shown in FIG5 , in some embodiments, the first RF conduction circuit 11 includes a bandpass filter.

[0143] The bandpass filter can pass high-frequency radio frequency signals of 5.9 GHz but cannot pass low-frequency signals (control signals), and has a simple structure.

[0144] In some embodiments, the first DC-passing and AC-isolating circuit 31 includes an equivalent inductor L.

[0145] In some embodiments, the first AC-passing and DC-blocking circuit 41 includes a first DC-blocking capacitor C1 .

[0146] For example, the capacitance of the first DC blocking capacitor C1 is nfdf level.

[0147] In some embodiments, the second AC-passing and DC-blocking circuit 51 includes a second DC-blocking capacitor C2 .

[0148] For example, the capacitance of the second DC blocking capacitor C2 is nfdf level.

[0149] In this way, the T-Box has a simple structure and low cost.

[0150] In some embodiments, as shown in FIG5 , the first RF isolation circuit 21 is an isolator.

[0151] For example, the frequency of the radio frequency signal is 5.9 GHz, and the first radio frequency isolation circuit 21 is a 5.9 GHz isolator.

[0152] In this way, the first radio frequency isolation circuit 21 is a finished device and can be directly coupled to the T-Box, which has a simple design.

[0153] In other embodiments, as shown in Figure 6, the first RF isolation circuit 21 includes a (1 / 4+N / 2)λ transmission line X, a first end of the (1 / 4+N / 2)λ transmission line X is coupled to the first junction Q1, a second end of the (1 / 4+N / 2)λ transmission line X is coupled to the first node P1, and the first node P1 is coupled to the second junction Q2.

[0154] Wherein, λ is the wavelength of the radio frequency signal, and N is an integer greater than or equal to 0.

[0155] For example, N=0, and the transmission line included in the first RF isolation circuit 21 is a 1 / 4λ transmission line. Alternatively, for example, N=1, and the transmission line included in the first RF isolation circuit 21 is a 3 / 4λ transmission line. Alternatively, for example, N=2, and the transmission line included in the first RF isolation circuit 21 is a (1 / 4+1)λ transmission line. Alternatively, for example, N=3, and the transmission line included in the first RF isolation circuit 21 is a (3 / 4+1)λ transmission line, etc.

[0156] The isolation of multiple radio frequency signals is achieved through transmission lines, with a simple structure and a small footprint.

[0157] In some embodiments, the T-Box further includes a circuit board, which may be, for example, a printed circuit board (PCB).

[0158] In some embodiments, the first branch 1 , the second branch 2 , and the third branch 3 are arranged on a circuit board.

[0159] In other embodiments, in the first branch 1, the second branch 2, and the third branch 3, except for the (1 / 4+N / 2)λ transmission line X, other components are arranged on the circuit board, and the (1 / 4+N / 2)λ transmission line X is integrated inside the circuit board.

[0160] In this way, the T-Box occupies a small area and has a low cost.

[0161] Continuing to refer to FIG. 6 , in some embodiments, the first RF isolation circuit 21 further includes a first capacitor C3 and a second capacitor C4 .

[0162] The first end of the first capacitor C3 and the first end of the second capacitor C4 are coupled to the reference ground voltage terminal GND, and the second end of the first capacitor C3 and the second end of the second capacitor C4 are coupled to the second end of the (1 / 4+N / 2)λ transmission line X.

[0163] For example, a second end of the first capacitor C3 is coupled to the first node P1 , and a second end of the second capacitor C4 is coupled to the first node P1 .

[0164] By providing the first capacitor C3 and the second capacitor C4, the frequency band deviation caused by the processing error of the (1 / 4+N / 2)λ transmission line X can be compensated, thereby optimizing the isolation effect of the radio frequency signal.

[0165] In some embodiments, the capacitance of the first capacitor C3 and the second capacitor C4 is in the pF range.

[0166] Setting the capacitance of the first capacitor C3 and the second capacitor C4 to pF level can achieve a better isolation effect on the radio frequency signal.

[0167] In some embodiments, the first capacitor C3 and the second capacitor C4 have the same capacitance.

[0168] The first capacitor C3 and the second capacitor C4 have equal capacitances, so that the first node P1 can serve as an endpoint of the first RF isolation circuit 21 , thereby improving the compensation accuracy for the (1 / 4+N / 2)λ transmission line X processing error.

[0169] Figure 7A is an architectural diagram of the transmission line network provided in an embodiment of the present application; Figure 7B is a simulation diagram of the isolation effect of the first RF isolation circuit 21 shown in Figure 6 on the RF signal provided in an embodiment of the present application; Figure 7C is a simulation diagram of the isolation effect of the first RF isolation circuit 21 shown in Figure 6 on the RF signal provided in an embodiment of the present application.

[0170] As shown in Figure 7A, in transmission line theory, a transmission line with a characteristic impedance of Z0 is connected to a terminal with an impedance of Z. L The two form a network.

[0171] For example, the characteristic impedance of the (1 / 4+N / 2)λ transmission line X is Z0, and the impedance of the first capacitor C3 and the second capacitor C4 is Z L , the first radio frequency isolation circuit 21 is regarded as a network.

[0172] Looking at the input impedance Z of this network I Will no longer be Z0. Input impedance Z I becomes:

[0173] Where β = 2π / λ, λ is the wavelength of the signal propagating in the network, and J is the imaginary unit. When l = λ / 4, the formula is derived as follows:

[0174] If the T-Box is open, then Z I = 0. If T-Box is short-circuited, Z I =∞. Therefore, when the (1 / 4+N / 2)λ transmission line X is used to connect the main channel (first branch 1) and the branches (second branch 2 and third branch 3), there is almost no attenuation of the RF signal on the main channel.

[0175] As shown in Figure 7B, simulation found that, taking the T-Box sending signal as an example, the RF signal is detected between the first junction Q1 and the connector 80, and the attenuation of the RF signal is about -0.025. These attenuations include the attenuation of the RF signal caused by the devices and signal lines between the V2X circuit and the sampling point, as well as the attenuation of the RF signal by the first RF isolation circuit 21. Therefore, the attenuation of the 5.9GHz RF signal by the first RF isolation circuit 21 is very small. As shown in Figure 7C, the RF signal is detected between the first node P1 and the second junction Q2, and the attenuation of the RF signal is about -24. Therefore, the RF signal is almost never transmitted to the second junction Q2 through the first RF isolation circuit 21.

[0176] Therefore, the first RF isolation circuit 21 based on the (1 / 4+N / 2)λ transmission line X isolates the RF signal while conducting the control signal, does not affect the normal transmission of the RF signal, and has a relatively small attenuation on the RF signal, which can be almost ignored.

[0177] Next, the control signal transmitted in the second branch 2 is described.

[0178] FIG8 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0179] As shown in FIG8 , in some embodiments, the first control signal terminal M1 includes a first gain control signal terminal UART1. The second branch 2 further includes a first controller 62, which is coupled to the first gain control signal terminal UART1 and configured to send a first gain control signal uart1 to the first gain control signal terminal UART1.

[0180] For example, the first controller 62 is further coupled to the V2X circuit 61. The V2X circuit 61 is configured to issue a transceiver control signal tx-en, which is configured to indicate whether the T-Box is transmitting or receiving a radio frequency signal. For example, when the transceiver control signal tx-en is 1, it indicates that the T-Box is transmitting a radio frequency signal. When the transceiver control signal tx-en is 0, it indicates that the T-Box is receiving a radio frequency signal.

[0181] For example, the V2X circuit 61 includes a modem, which is used to output a transceiver control signal tx-en.

[0182] The first controller 62 receives the transceiver control signal tx-en, and after receiving the transceiver control signal tx-en, transmits the first gain control signal uart1 to the first gain control signal terminal UART1 in combination with the transceiver control signal tx-en.

[0183] For example, the transceiver control signal tx-en received by the first controller 62 is used to indicate that the T-Box is transmitting a radio frequency signal. The first controller 62 sends a first gain control signal uart1 to the first gain control signal terminal UART1. The first gain control signal uart1 is used to represent the gain adjustment value of the relay for the radio frequency signal.

[0184] The transceiver control signal tx-en received by the first controller 62 is used to instruct the T-Box to receive a radio frequency signal, and the first controller 62 does not send the first gain control signal uart1.

[0185] In some embodiments, the first controller 62 may be, for example, a microcontroller unit (MCU) of the T-Box. The first controller 62 may also be a device disposed on a circuit board of the T-Box.

[0186] In addition, in some embodiments, the first gain control signal uart1 may be a signal that directly represents the relay gain value. After the relay receives the first gain control signal uart1, the gain value may be directly obtained.

[0187] Then, for different vehicles 100 , simulation tests can be performed before delivery, and the gain values ​​represented by the first gain control signal can be set in advance for different cable lengths.

[0188] For example, for a first type of vehicle, the first gain control signal uart1 issued by the first controller 62 directly represents a gain value of 2. For a second type of vehicle, the first gain control signal uart1 issued by the first controller 62 directly represents a gain value of 3.

[0189] In other embodiments, the first gain control signal uart1 may also be a signal carrying a gain value. After the relay receives the first gain control signal uart1, the first gain control signal uart1 still needs to be further processed to obtain the gain value.

[0190] Then, the first controller 62 can generate the same first gain control signal uart1 for different vehicles 100. The relay can further generate a gain control signal representing the gain value based on the first gain control signal uart1 according to different cable lengths. This allows the signal transmission system to adapt to different vehicles 100.

[0191] FIG9 is a schematic diagram of a T-Box framework provided in an embodiment of the present application.

[0192] As shown in Figure 9, in some embodiments, the first control signal terminal M1 also includes a first transceiver control signal terminal TX-EN1, which is coupled to the V2X circuit 61 and is used to receive the transceiver control signal tx-en output by the V2X circuit 61.

[0193] The first controller 62 is configured to receive the transceiver control signal tx-en from the first transceiver control signal terminal TX-EN1 and output a first gain control signal uart1 to the first gain control signal terminal UART1 .

[0194] For example, the first controller 62 is coupled to the first gain control signal terminal UART1 and the first transceiver control signal terminal TX-EN1.

[0195] In some embodiments, the second branch 2 further includes a modulation circuit 70 , an input end of the modulation circuit 70 is coupled to the first gain control signal end UART1 and the first transceiver control signal end TX-EN1 , and an output end of the modulation circuit 70 is coupled to the first RF isolation circuit 21 .

[0196] In the case that the second branch 2 further includes a second AC-passing and DC-blocking circuit 51 , the second end of the modulation circuit 70 is coupled to the second AC-passing and DC-blocking circuit 51 .

[0197] That is, the modulation circuit 70 modulates the first gain control signal uart1 and the first transceiver control signal tx-en and transmits them in the second branch 2. Therefore, in addition to the first gain control signal uart1, the second branch 2 can also transmit the first transceiver control signal tx-en.

[0198] In some embodiments, the modulation circuit 70 includes a first AND gate AND1 .

[0199] An input terminal of the first AND gate AND1 is coupled to both the first gain control signal terminal UART1 and the first transceiver control signal terminal TX-EN1 . An output terminal of the first AND gate AND1 is coupled to the first RF isolation circuit 21 .

[0200] In this case, the first AND gate AND1 can be understood as a double AND gate. The first AND gate AND1 performs AND modulation on the first gain control signal and the first transceiver control signal, so that the modulated signal output by the first AND gate AND1 contains information of the first gain control signal and the first transceiver control signal.

[0201] After modulating the transceiver control signal tx-en transmitted by the first transceiver control signal terminal TX-EN1 and the first gain control signal uart1 transmitted by the first gain control signal terminal UART1 through modulation circuit 70, the second branch 2 can synchronously transmit the first transceiver control signal tx-en and the first gain control signal uart1 to the first combining point Q1 for transmission via the cable. This increases the amount of information in the aggregated signal transmitted in the cable, eliminating the need for a separate first transceiver control signal tx-en branch.

[0202] In some embodiments, the second branch 2 further includes an operational amplifier (OP), and the operational amplifier OP is coupled between the modulation circuit 70 and the first RF isolation circuit 21 (the second AC-passing and DC-isolating circuit 51 ).

[0203] By providing an operational amplifier OP at the output end of the modulation circuit 70 , the signal modulated by the modulation circuit 70 can be amplified / attenuated and then transmitted to the first summing point Q1 to meet the needs of different application scenarios.

[0204] FIG10 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0205] As shown in FIG. 10 , in some embodiments, the second branch 2 further includes a carrier circuit 64 , which is configured to output a carrier signal; the carrier circuit 64 is coupled to an input terminal of the modulation circuit 70 .

[0206] For example, the carrier signal output by the carrier circuit 64 is a clock signal clk. For example, the clock signal clk is a signal with a frequency of 100 MHz. For example, the clock signal clk is a 125 MHz signal. Of course, the clock signal clk can also be a signal of other frequencies.

[0207] For example, the carrier circuit 64 is a clock oscillator, which is used to generate a clock signal with a frequency of 125 MHz. Of course, the clock signal generated by the clock oscillator can also have other frequencies, as long as the frequency of the clock signal is different from the frequency of the RF signal.

[0208] As shown in FIG10 , the input of the first AND gate AND1 is coupled to both the first gain control signal terminal UART1 and the carrier circuit 64, and the output of the first AND gate AND1 is coupled to the first RF isolation circuit 21. The first AND gate AND1 modulates the first gain control signal uart1 and the carrier signal. In this case, the first AND gate AND1 can be understood as a double AND gate.

[0209] By setting a carrier signal to carry the control signal and assist in the transmission of the control signal, the transmission effect of the control signal can be improved. Using a clock signal as a carrier signal can easily separate the clock signal from the first gain control signal after receiving the modulated signal, and data loss is unlikely during separation.

[0210] FIG11 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0211] As shown in FIG. 11 , in some embodiments, the second branch 2 includes a carrier circuit 64 , and the first control signal terminal M1 includes both a first gain control signal terminal UART1 and a first transceiver control signal terminal TX-EN1 .

[0212] In this case, illustratively, the modulation circuit 70 includes a first AND gate AND1 , which can be understood as a triple AND gate.

[0213] An input terminal of the first AND gate AND1 is coupled to the carrier circuit 64 , the first transceiver control signal terminal TX-EN1 , and the first gain control signal terminal UART1 . An output terminal of the first AND gate AND1 is coupled to the second AC / DC blocking circuit 51 or the operational amplifier OP.

[0214] Then, the first AND gate AND1 can modulate the first gain control signal uart1, the first transceiver control signal tx-en, and the carrier signal, and transmit them to the relay through the cable.

[0215] FIG12 is a schematic diagram of a framework of a T-Box provided in an embodiment of the present application.

[0216] Alternatively, for example, the modulation circuit 70 includes a second AND gate AND2 and a third AND gate AND3 , and both the second AND gate AND2 and the third AND gate AND3 are double AND gates.

[0217] An input terminal of the second AND gate AND2 is coupled to two of the carrier circuit 64 , the first transceiver control signal terminal TX-EN1 , and the first gain control signal terminal UART1 . An output terminal of the second AND gate AND2 is coupled to an input terminal of the third AND gate AND3 .

[0218] An input end of the third AND gate AND3 is also coupled to the carrier circuit 64, the first transceiver control signal terminal TX-EN1, and the remaining one of the first gain control signal terminal UART1. An output end of the third AND gate AND3 is coupled to the first RF isolation circuit 21 (the second AC-passing and DC-isolating circuit 51).

[0219] It can also be understood that after two of the carrier circuit 64, the first transceiver control signal terminal TX-EN1, and the first gain control signal terminal UART1 are coupled to the second AND gate AND2, the other is coupled to the third AND gate AND3 at the output terminal of the second AND gate AND2. This embodiment of the present application does not limit which two of the carrier circuit 64, the first transceiver control signal terminal TX-EN1, and the first gain control signal terminal UART1 are coupled to the second AND gate AND902 first; FIG12 is merely an example.

[0220] For example, as shown in Figure 12, the carrier circuit 64 and the first transceiver control signal terminal TX-EN1 are coupled to the input terminal of the second AND gate AND2, the output terminal of the second AND gate AND2 and the first gain control signal terminal UART1 are coupled to the input terminal of the third AND gate AND3, and the output terminal of the third AND gate AND3 is coupled to the second AC-DC blocking circuit 51 or the operational amplifier OP.

[0221] Alternatively, for example, the carrier circuit 64 and the first gain control signal terminal UART1 are coupled to the input terminal of the second AND gate AND2, and the output terminal of the second AND gate AND2 and the first transceiver control signal terminal TX-EN1 are coupled to the input terminal of the third AND gate AND3.

[0222] Alternatively, for example, the first gain control signal terminal UART1 and the first transceiver control signal terminal TX-EN1 are coupled to the input terminal of the second AND gate AND2, and the output terminal of the second AND gate AND2 and the carrier circuit 64 are coupled to the input terminal of the third AND gate AND3.

[0223] FIG13 is a diagram showing a modulation result of a modulation circuit 70 provided in an embodiment of the present application.

[0224] In Figure 13 , the abscissa represents time, and the ordinate represents voltage. From top to bottom, the waveforms of the signal from carrier circuit 64, the signal from the first transceiver control signal terminal TX-EN1, the signal from the first gain control signal terminal UART1, and the modulated signal are shown. After modulation by modulation circuit 70, the modulated signal includes the signal from carrier circuit 64, the signal from the first transceiver control signal terminal TX-EN1, and the signal from the first gain control signal terminal UART1, thus carrying three types of information.

[0225] Example 2

[0226] FIG14 is a schematic diagram of a relay framework provided in an embodiment of the present application.

[0227] An embodiment of the present application provides a relay, as shown in FIG14 , the relay includes a fourth branch 4 and a fifth branch 5 .

[0228] The fourth branch 4 includes a vehicle-to-anything (V2X) signal terminal and a bidirectional switch circuit 13. The bidirectional switch circuit 13 includes a first path L1 and a second path L2 coupled in parallel between the V2X signal terminal and a third junction Q3. The first path L1 includes a first power amplifier PA1, and the output terminal of the first power amplifier PA1 is coupled to the V2X signal terminal.

[0229] The V2X signal terminal is coupled to the antenna and is used to transmit and receive radio frequency signals. The V2X signal terminal can be used to receive radio frequency signals, and the V2X signal terminal can also be used to transmit radio frequency signals. The radio frequency signals can be the same as those in Example 1 and are not further described here.

[0230] When the relay is used to receive RF signals from the T-Box, the third combining point Q3 receives the RF signals and transmits them to the V2X signal end via the first path L1 (first power amplifier PA1). When the relay is used to send signals to the T-Box, the RF signals sent by the V2X signal end are transmitted to the third combining point Q3 via the second path S2.

[0231] It can also be understood that the fourth branch 4 transmits a radio frequency signal, and the radio frequency signal can be transmitted from the V2X signal end to the third combining point Q3, and the radio frequency signal can also be transmitted from the third combining point Q3 to the V2X signal end.

[0232] A bidirectional switching circuit refers to a circuit that contains a bidirectional line. Signals can be transmitted in both directions, but the signal can only be transmitted in one direction at a time and cannot be transmitted in both directions at the same time.

[0233] In some embodiments, the bidirectional switch circuit is, for example, a half-duplex circuit.

[0234] Then, when the relay is used to receive signals, the first path L1 is conductive, and when the relay is used to send signals, the second path S2 is conductive.

[0235] The fifth branch 5 includes a second control signal terminal M2 and a second RF isolation circuit 22. The second control signal terminal M2 is coupled to the bidirectional switch circuit 13. The second RF isolation circuit 22 is coupled between the second control signal terminal M2 and the third junction Q3.

[0236] The second control signal terminal M2 is used to receive a control signal. The control signal received by the second control signal terminal M2 matches the control signal sent by the first control signal terminal M1 in the T-Box.

[0237] It can also be understood that what is transmitted in the fifth branch 5 is a control signal, and the control signal can be transmitted from the third combining point Q3 to the second control signal terminal M2.

[0238] The control signal is, for example, a control signal transmitted by the T-Box. Please refer to the relevant description of the control signal in Example 1, which will not be repeated here.

[0239] Then, when the relay is used to send signals, the RF signal transmitted by the fourth branch 4 is output via the third combining point Q3. When the relay is used to receive signals, the RF signal in the aggregated signal (including the RF signal and the control signal) transmitted by the third combining point Q3 is transmitted to the V2X signal terminal via the fourth branch 4, and the control signal in the aggregated signal (that is, the modulated signal mentioned above) is transmitted to the second control signal terminal M2 via the fifth branch 5.

[0240] In some embodiments, in order to prevent the signals on the fourth branch 4 and the fifth branch 5 from interfering with each other, the second RF isolation circuit 22 in the fifth branch 5 is used to pass the control signal and isolate the RF signal.

[0241] In some embodiments, the fourth branch 4 further includes a second RF conduction circuit 12 coupled between the bidirectional switch circuit 13 and the third junction Q3 . The second RF conduction circuit 12 is configured to pass RF signals and isolate control signals.

[0242] For example, the second RF conduction circuit 12 includes a bandpass filter. The second RF conduction circuit 12 may be the same as the first RF conduction circuit 11 or may be different from the first RF conduction circuit 11 .

[0243] In some embodiments, as shown in FIG. 14 , the second path S2 in the bidirectional switch circuit 13 includes a second power amplifier PA2 .

[0244] Illustratively, the second power amplifier PA2 includes a low noise amplifier (LNA), and an output terminal of the LNA is coupled to the third combining point Q3.

[0245] Based on this, optionally, the second control signal terminal M2 is coupled to the bidirectional switch circuit 13 , and the second control signal terminal M2 may be coupled to the first power amplifier OP1 and the second power amplifier OP2 , respectively.

[0246] For example, the control signal includes a first gain control signal, and the first gain control signal is used to control the amplification factors of the first power amplifier OP1 and the second power amplifier OP2.

[0247] Then, the second control signal terminal M2 includes a second gain control signal terminal, and the second gain control signal terminal is coupled to the first power amplifier OP1 and the second power amplifier OP2 respectively.

[0248] Alternatively, for example, the control signal further includes a transceiver control signal, and the transceiver control signal is further used to control the first power amplifier OP1 or the second power amplifier OP2 to be turned on.

[0249] Then, as shown in FIG15 , the second control signal terminal M2 includes a second gain control signal terminal UART2 and a second transceiver control signal terminal TX-EN2 , and the second transceiver control signal terminal TX-EN2 is coupled to the first power amplifier OP1 and the second power amplifier OP2 , respectively.

[0250] In this way, when the radio frequency signal is transmitted on the second path S2, the low noise amplifier can amplify the radio frequency signal according to demand.

[0251] In some embodiments, the relay further includes a connector 80 .

[0252] One end of the connector 80 is coupled to the third junction Q3 , and the other end of the connector 80 is used to couple to a cable.

[0253] In some embodiments, as shown in FIG. 15 , the fifth branch 5 further includes a second controller 65 and a first frequency band blocking circuit 71 .

[0254] The first frequency band blocking circuit 71 is coupled between the second transceiver control signal terminal TX-EN2 and a second node P2 . The second node P2 is coupled to the second RF isolation circuit 22 .

[0255] The blocking frequency band of the first frequency band blocking circuit 71 matches the frequency band of the first gain control signal uart1 and is used to block the first gain control signal uart1 and pass the transceiver control signal tx-en.

[0256] Illustratively, the first frequency band blocking circuit 71 includes a low-pass filter or a detector.

[0257] The control signals received by the third combining point Q3 include the first gain control signal uart1 and the transceiver control signal tx-en. These control signals are transmitted to the second node P2. The first frequency band blocking circuit 71 blocks the first gain control signal uart1 and transmits the transceiver control signal tx-en to the second transceiver control signal terminal TX-EN2 via the transceiver control signal tx-en. The second transceiver control signal terminal TX-EN2 is coupled to the bidirectional switch circuit 13 and is used to control the conduction of the first power amplifier PA1 or the second power amplifier PA2.

[0258] The second controller 65 is configured to output a second gain control signal uart2 to the second gain control signal terminal UART2 after receiving the transceiver control signal tx-en of the second transceiver control signal terminal TX-EN2 and the control signal of the second node P2.

[0259] For example, the output terminal of the second controller 65 is coupled to the second gain control signal terminal UART2, and the input terminal of the second controller 65 is coupled to the second transceiver control signal terminal TX-EN2 and the second node P2. The second controller 65 is configured to receive the transceiver control signal tx-en of the second transceiver control signal terminal TX-EN2 and the control signal of the second node P2, and output the second gain control signal uart2 to the second gain control signal terminal UART2 according to the transceiver control signal tx-en and the control signal of the second node P2.

[0260] The modulation signal (control signal) at the second node P2 and the transceiver control signal tx-en at the second transceiver control signal terminal TX-EN2 are both transmitted to the second controller 65. The second controller 65 determines whether the relay is used to transmit or receive signals based on the transceiver control signal tx-en. When the relay is used to receive signals, the second controller 65 decodes the modulation signal to generate a second gain control signal uart2. The second gain control signal uart2 is transmitted to the bidirectional switch circuit 13 for controlling the gain of the first power amplifier PA1. When the relay is used to transmit signals, the second controller 65 does not decode the modulation signal, and the gain of the second power amplifier PA2 is the set gain.

[0261] The second controller 65 may be, for example, an MCU of the relay, or a device disposed on a circuit board of the relay.

[0262] FIG16 is a schematic diagram of a relay framework provided in an embodiment of the present application.

[0263] As shown in FIG. 16 , in some embodiments, the fifth branch 5 further includes a second frequency band blocking circuit 72 , and the second frequency band blocking circuit 72 is coupled between the second node P2 and the second RF isolation circuit 22 .

[0264] The blocking frequency band of the second frequency band blocking circuit 72 matches the frequency band of the carrier signal (eg, the clock signal clk) and is used to block the carrier signal and pass the first gain control signal uart1 and the transceiver control signal tx-en.

[0265] Illustratively, the second frequency band blocking circuit 72 includes a low-pass filter or a detector.

[0266] In some embodiments, the blocking frequency of the second frequency band blocking circuit 72 is higher than the blocking frequency band of the first frequency band blocking circuit 71 .

[0267] Then, the modulated signal transmitted by the second RF isolation circuit 22 is first blocked by the second frequency band blocking circuit 72, and the clock signal clk is removed. The first gain control signal uart1 and the transceiver control signal tx-en are then transmitted to the second node P2 for transmission to the second controller 65 and the first frequency band blocking circuit 71. The first frequency band blocking circuit 71 then filters out the first gain control signal uart1 and transmits the transceiver control signal tx-en to the second transceiver control signal terminal TX-EN2. The second controller 65 recognizes the first gain control signal uart1 and outputs the second gain control signal uart2.

[0268] FIG17 is a framework diagram of a relay provided in an embodiment of the present application.

[0269] In some embodiments, as shown in FIG. 17 , the fifth branch 5 further includes a first signal enhancement circuit 90 , and the first signal enhancement circuit 90 is coupled between the second controller 65 and the second node P2 .

[0270] The first signal enhancement circuit 90 is used to enhance the signal at the second node P2 and transmit it to the second controller 65. The enhancement method includes but is not limited to amplification. The present embodiment does not limit the structure of the first signal enhancement circuit 90. Any circuit that can enhance signal strength is applicable to the present embodiment.

[0271] By providing the first signal enhancement circuit 90 between the second controller 65 and the second node P2 , the signal of the second node P2 can be enhanced before being transmitted to the second controller 65 , thereby improving the accuracy of signal processing.

[0272] In some embodiments, the fifth branch 5 further includes a second signal enhancement circuit, and the second signal enhancement circuit is coupled between the second controller 65 and the second transceiver control signal terminal TX-EN2.

[0273] The second signal enhancement circuit is used to enhance the signal at the second transceiver control signal terminal TX-EN2 before transmitting it to the second controller 65. The enhancement method includes but is not limited to amplification. The present embodiment does not limit the structure of the second signal enhancement circuit. Any circuit that can enhance signal strength is applicable to the present embodiment.

[0274] By providing a second signal enhancement circuit between the second controller 65 and the second transceiver control signal terminal TX-EN2, the signal of the second transceiver control signal terminal TX-EN2 can be enhanced before being transmitted to the second controller 65, thereby improving the accuracy of the signal.

[0275] In some other embodiments, the fifth branch 5 further includes a third signal enhancement circuit, and the third signal enhancement circuit is coupled between the second node P2 and the second RF isolation circuit 22 .

[0276] The third signal enhancement circuit is used to enhance the modulated signal output by the second RF isolation circuit 22 before outputting it. The enhancement method includes but is not limited to amplification. The present embodiment does not limit the structure of the third signal enhancement circuit. Any circuit that can enhance signal strength is applicable to the present embodiment.

[0277] By providing a second signal enhancement circuit between the second node P2 and the second RF isolation circuit 22 , the signal output by the second RF isolation circuit 22 can be enhanced before being transmitted to the second node P2 , thereby improving the accuracy of the signal.

[0278] FIG18 is a framework diagram of a relay provided in an embodiment of the present application.

[0279] In some embodiments, as shown in Figure 18, the relay also includes a power detector 99, which is coupled to the second controller 65 and the third junction Q3 respectively. The second controller 65 is also configured to receive the power signal sent by the power detector before outputting the second gain control signal uart2 to the second gain control signal terminal UART2.

[0280] Specifically, the second gain control signal uart2 is determined according to the first gain control signal uart1 and the power signal.

[0281] The power detector 99 can be, for example, a power voltage detector tube. The power detector 99 is used to convert the RF signal strength at the third junction Q3 into a voltage value, determine the power of the RF signal based on the voltage value, and inform the second controller 65 of the power signal. The second controller 65 outputs a second gain control signal uart2 based on the first gain control signal uart1 (characterizing the power strength of the RF signal output by the T-Box) and the power signal output by the power detector 99 (characterizing the power strength of the RF signal after the cable loss) to perform corresponding gain control on the first power amplifier PA1. The gain value of the second gain control signal uart2 output by the second controller 65 is different for different cable lengths, so that the signal transmission system has the function of adaptively adapting to different cable lengths, so that the signal transmission system provided in the embodiment of the present application can be applicable to vehicles 100 with cables of various lengths.

[0282] For example, the line loss magnitude can be determined by comparing the difference between the first gain control signal uart1 and the power signal output by the power detector 99. The gain of the first power amplifier PA1 is then converted based on the line loss (e.g., a line loss-to-gain comparison table is stored in the second controller 65), and a second gain control signal uart2 is output to the first power amplifier PA1 so that the power of the signal output by the first power amplifier PA1 is the same as that of the first gain control signal uart1. Alternatively, the power of the signal output by the first power amplifier PA1 is different from that of the first gain control signal uart1, but the difference between the two is within an acceptable line loss range.

[0283] For example, the power detector 99 can be coupled to the third junction Q3. Alternatively, for example, the power detector 99 can be coupled between the second RF conduction circuit 12 and the bidirectional switch circuit 13. The power detector 99 can receive the RF signal.

[0284] Of course, in some embodiments, the relay may not include the power detector 99. The T-Box predetermines the line loss for different cable lengths and outputs a first gain control signal uart1 that matches the line loss. This first gain control signal uart1 controls the gain of the first power amplifier PA1. This allows the signal transmission system to be pre-set for different vehicles 100. The signal transmission system provided by the present embodiment is still applicable to vehicles 100 with various cable lengths.

[0285] FIG19 is a topological diagram of a relay provided in an embodiment of the present application.

[0286] In some embodiments, as shown in FIG. 19 , the relay further includes a sixth branch 6 , and the sixth branch 6 includes a second power supply circuit 66 .

[0287] The second power circuit 66 is coupled to a fourth junction Q4 . The fourth junction Q4 is located between the second RF isolation circuit 22 and the second control signal terminal M2 .

[0288] For example, the fourth combining point Q4 is located between the second RF isolation circuit 22 and the second frequency band blocking circuit 72 .

[0289] The second power supply circuit 66 is used to receive direct current. After receiving the direct current, the second power supply circuit 66 can convert the direct current and then supply it to the relay, or can directly supply it to the relay. This embodiment of the present application does not limit this.

[0290] In some embodiments, as shown in FIG. 19 , the fourth branch 4 further includes a third AC-passing and DC-isolating circuit 42 . The third AC-passing and DC-isolating circuit 42 is coupled between the bidirectional switch circuit 13 and the third junction Q3 .

[0291] The embodiment of the present application does not limit the structure of the third AC-passing and DC-blocking circuit 42. For example, the third AC-passing and DC-blocking circuit 42 includes a third DC-blocking capacitor C5. The third DC-blocking capacitor C5 may have the same structure as the first DC-blocking capacitor C1.

[0292] In some embodiments, the fifth branch 5 further includes a fourth AC-passing and DC-isolating circuit 52 , which is coupled between the second control signal terminal M2 (the second frequency band blocking circuit 72 ) and the fourth junction Q4 .

[0293] The embodiment of the present application does not limit the structure of the fourth AC-passing and DC-blocking circuit 52. For example, the fourth AC-passing and DC-blocking circuit 52 includes a fourth DC-blocking capacitor C6. The fourth DC-blocking capacitor C6 may have the same structure as the second DC-blocking capacitor C2.

[0294] In some embodiments, the sixth branch 6 further includes a second DC-passing and AC-isolating circuit 32 , and the second DC-passing and AC-isolating circuit 32 is coupled between the second power circuit 66 and the fourth junction Q4 .

[0295] The embodiment of the present application does not limit the structure of the second DC-passing and AC-isolating circuit 32 . For example, the second DC-passing and AC-isolating circuit 32 includes an equivalent inductor L.

[0296] In some embodiments, the structure of the second RF isolation circuit 22 may be the same as that of the first RF isolation circuit 21 .

[0297] For example, as shown in FIG19 , the second RF isolation circuit 22 includes a (1 / 4+N / 2)λ transmission line X, wherein a first end of the (1 / 4+N / 2)λ transmission line X is coupled to a third junction Q3, and a second end of the (1 / 4+N / 2)λ transmission line X is coupled to a third node P3. The third node P3 is coupled to a fourth node Q4, and the fourth node Q4 is coupled to the second control signal terminal M2 and the second power supply circuit 66, respectively.

[0298] In some embodiments, the second RF isolation circuit 22 further includes a third capacitor C7 and a fourth capacitor C8.

[0299] A first end of the third capacitor C7 and a first end of the fourth capacitor C8 are both coupled to the reference ground voltage terminal GND, and a second end of the third capacitor C7 and a second end of the fourth capacitor C8 are both coupled to the third node P3.

[0300] The relay provided in the embodiments of the present application receives a control signal from the T-Box and adjusts the relay itself in conjunction with the control signal, making the relay dynamically adjustable to meet the needs of different application scenarios. When the control signal includes a first gain control signal, the relay can adjust its gain value in conjunction with the first gain control signal to adapt to the line loss in different vehicles 100. In this way, a single set of signal transmission cores can be adapted to a variety of different vehicles 100, achieving extremely high adaptability and low cost.

[0301] Example 3

[0302] FIG20 is an architectural diagram of a signal transmission system provided in an embodiment of the present application.

[0303] An embodiment of the present application provides a signal transmission system, as shown in FIG20 , the signal transmission system includes a T-Box, a cable, and a relay, where both ends of the cable are coupled to a connector 80 in the T-Box and a connector 80 in the relay, respectively.

[0304] It should be understood that the connector 80 in the T-Box and the connector 80 in the relay may be the same or different, and this embodiment of the present application does not limit this.

[0305] The V2X signal end of the relay in the signal transmission system is used to couple with the antenna. When the signal transmission system is applied to a vehicle, the antenna is the V2X antenna of the vehicle.

[0306] In some embodiments, the T-Box in the signal transmission system includes any T-Box shown in Example 1, and the relay in the signal transmission system includes any relay shown in Example 2. FIG20 is only an illustration and does not limit the present invention.

[0307] Below, taking FIG. 20 as an example, the communication process of the signal transmission system is schematically described.

[0308] The T-Box sends an aggregate signal to the relay. The aggregate signal includes the RF signal transmitted by the first branch 1, the modulated signal transmitted by the second branch 2 (including the signal from the carrier circuit 64, the signal from the first gain control signal terminal UART1, and the signal from the first transceiver control signal terminal TX-EN1), and the power current transmitted by the third branch 3. The aggregate signal is transmitted to the relay via the cable, and the signal received at the third combining point Q3 of the relay is the aggregate signal.

[0309] The RF signal in the aggregate signal is isolated by the second RF isolation circuit 22 and cannot reach the fifth branch 5 and the sixth branch 6 , but the RF signal can be transmitted in the fourth branch 4 to the bidirectional switch circuit 13 .

[0310] The power current in the aggregate signal is isolated by the third AC / DC isolation circuit 42 and the fourth AC / DC isolation circuit 52 and cannot reach the fourth branch 4 and the fifth branch 5 . However, the power current can be transmitted to the second power circuit 66 in the sixth branch 6 .

[0311] The modulated signal in the aggregated signal is isolated by the second RF conduction circuit 12 and cannot reach the fourth branch 4. However, the modulated signal can reach the fourth node Q4 through the second RF isolation circuit 22. After reaching the fourth node Q4, the modulated signal is isolated by the second DC-passing and AC-isolating circuit 32 and cannot reach the sixth branch 6. However, the modulated signal can reach the fifth branch 5.

[0312] The modulated signal includes a carrier signal (e.g., clock signal clk) output by carrier circuit 64, a first gain control signal uart1 output by first gain control signal terminal UART1, and a transceiver control signal tx-en output by first transceiver control signal terminal TX-EN1. The clock signal clk in the modulated signal is blocked by second frequency band blocking circuit 72 and cannot reach second node P2. However, the first gain control signal uart1 and transceiver control signal tx-en in the modulated signal can reach second node P2. The first gain control signal uart1 at second node P2 is blocked by first frequency band blocking circuit 71 and cannot be transmitted to second transceiver control signal terminal TX-EN2. However, the transceiver control signal tx-en can be transmitted to second transceiver control signal terminal TX-EN2. The transceiver control signal tx-en is transmitted to bidirectional switch circuit 13 via second transceiver control signal terminal TX-EN2 to control the first power amplifier PA1 in bidirectional switch circuit 13 to conduct and the second control amplifier PA2 to conduct. Synchronously, the modulated signal composed of the first gain control signal uart1 and the transceiver control signal tx-en at the second node P2 is transmitted to the second controller 65. The transceiver control signal tx-en at the second transceiver control signal terminal TX-EN2 is also transmitted to the second controller 65. The second controller 65 determines whether to decode the modulated signal based on the transceiver control signal tx-en to adjust whether to output the second gain control signal uart2.

[0313] For example, when tx-en = 1, the first power amplifier PA1 is turned on and the second power amplifier PA2 is turned off. When tx-en = 0, the first power amplifier PA1 is turned off and the second power amplifier PA2 is turned on. When tx-en = 0, the second controller 65 does not decode the modulated signal, and the second power amplifier PA2 amplifies it according to the set gain. When tx-en = 1, the second controller 65 decodes the modulated signal and outputs the second gain control signal uart2 to control the gain of the first power amplifier PA1.

[0314] When the signal transmission system is transmitting signals to the antenna, tx-en = 1, the first power amplifier PA1 is turned on, and the second power amplifier PA2 is turned off. Simultaneously, the second controller 65 decodes the modulated signal and outputs a second gain control signal uart2 to control the gain of the first power amplifier PA1. The RF signal transmitted by the T-Box to the fourth branch 4 is amplified by the first power amplifier PA1 and then transmitted to the antenna via the V2X signal terminal, completing the signal transmission to the antenna.

[0315] It should be noted that, in conjunction with the above description of the T-Box, the first gain control signal uart1 included in the modulated signal can be of two types. The first type: the first gain control signal uart1 directly includes information indicating the specific gain value of the first power amplifier PA1. The second type: the first gain control signal uart1 carries information that can be used to obtain the specific gain value of the first power amplifier PA1. In the first case, the second controller 65 decodes the modulated signal to directly obtain the gain value and output it as the second gain control signal uart2. In this case, knowing the line loss in advance and setting the gain value allows the signal transmission system to adapt to different vehicles 100. In the second case, the second controller 65 decodes the modulated signal and processes it with the signal input from the power detector 99 to obtain the gain value and output it as the second gain control signal uart2. In this case, there is no need to know the line loss in advance. The second controller 65 automatically calculates the line loss and outputs the appropriate gain value, allowing the signal transmission system to adaptively adapt to different vehicles 100.

[0316] When the signal transmission system is used to receive the signal sent by the antenna, tx-en = 0, the first power amplifier PA1 is turned off, and the second power amplifier PA2 is turned on. At the same time, the second controller 65 does not decode the modulated signal. The RF signal sent by the antenna is amplified by the second power amplifier PA2 and transmitted to the third combining point Q3. The third combining point Q3 transmits the RF signal to the first combining point Q1 via a cable. The first RF isolation circuit 21 has a blocking effect on the RF signal, and the RF signal will not be transmitted to the second combining point Q2. However, the RF signal can be transmitted to the V2X circuit 61 via the first RF conduction circuit 11 to complete the reception of the antenna signal.

[0317] In some embodiments, the radio frequency signal emitted by the V2X circuit 61 in the T-Box is set to have a conventional power. However, under special instructions, the power of the radio frequency signal emitted by the T-Box is adjustable, and the power of the radio frequency signal emitted by the V2X circuit 61 in the T-Box can be adjusted to adapt to different scenarios.

[0318] In some embodiments, it is necessary to reduce the power of the radio frequency signal emitted by the T-Box.

[0319] For example, when vehicle 100 approaches an electronic toll collection (ETC) system, the frequency band of the RF signal can be adjusted to prevent the RF signal from interfering with the ETC signal. The T-Box then determines whether vehicle 100 is at an ETC toll station. If so, the T-Box adjusts (e.g., reduces) the power of the RF signal emitted by V2X circuit 61. The relay continues to perform gain compensation according to the original scheme to reduce the power of the RF signal received by the antenna and mitigate interference.

[0320] The present embodiment does not limit the method by which the T-Box determines whether the vehicle 100 is located at an ETC toll station, and all solutions in related technologies are applicable to the present embodiment. For example, the global positioning system (GPS) can be used to determine whether the vehicle 100 is located at an ETC toll station.

[0321] In other embodiments, it is necessary to increase the power of the radio frequency signal emitted by the T-Box.

[0322] The above is only a specific embodiment of the present application, but the scope of protection of this application is not limited to this. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A vehicle-mounted communication terminal T-Box, characterized in that: include: A first branch (1) comprises a vehicle-to-anything (V2X) circuit (61) and a first radio frequency conduction circuit (11), wherein the first radio frequency conduction circuit (11) is coupled between the V2X circuit (61) and a first junction point (Q1); the V2X circuit (61) is used to send and receive radio frequency signals; The second branch (2) comprises a first control signal terminal (M1) and a first radio frequency isolation circuit (21), wherein the first radio frequency isolation circuit (21) is coupled between the first control signal terminal (M1) and the first junction point (Q1); the first control signal terminal (M1) is used to output a control signal; The first radio frequency conduction circuit (11) is used for passing the radio frequency signal and isolating the control signal, and the first radio frequency isolation circuit (21) is used for passing the control signal and isolating the radio frequency signal.

2. The T-Box according to claim 1, characterized in that: The first radio frequency isolation circuit (21) comprises a (1 / 4+N / 2)λ transmission line (X); a first end of the (1 / 4+N / 2)λ transmission line (X) is coupled to the first junction (Q1), and a second end of the (1 / 4+N / 2)λ transmission line (X) is coupled to a first node (P1); and the first node (P1) is coupled to the first control signal terminal (M1); Wherein, λ is the wavelength of the radio frequency signal, and N is an integer greater than or equal to 0.

3. The T-Box according to claim 2, characterized in that: The first radio frequency isolation circuit (21) further includes a first capacitor (C3) and a second capacitor (C4); The first end of the first capacitor (C3) and the first end of the second capacitor (C4) are both coupled to the reference ground voltage terminal (GND), and the second end of the first capacitor (C3) and the second end of the second capacitor (C4) are both coupled to the first node (P1).

4. The T-Box according to claim 1, characterized in that: The first radio frequency isolation circuit (21) comprises an isolator.

5. The T-Box according to any one of claims 1 to 4, characterized in that: The T-Box further comprises a third branch (3); The third branch (3) comprises a first power supply circuit (63), the first power supply circuit (63) is coupled to a second junction point (Q2), and the second junction point (Q2) is located between the first radio frequency isolation circuit (21) and the first control signal terminal (M1).

6. The T-Box according to claim 5, characterized in that: The first branch (1) further comprises a first AC-connected and DC-isolated circuit (41), wherein the first AC-connected and DC-isolated circuit (41) is coupled in series with the first radio frequency conduction circuit (11) and is connected between the V2X circuit (61) and the first junction point (Q1); and / or, The second branch (2) further comprises a second AC-passing and DC-isolating circuit (51), wherein the second AC-passing and DC-isolating circuit (51) is coupled between the first control signal terminal (M1) and the second combining point (Q2); and / or, The third branch (3) further comprises a first direct current-passing and alternating current-isolating circuit (31), wherein the first direct current-passing and alternating current-isolating circuit (31) is coupled between the first power supply circuit (63) and the second junction point (Q2).

7. The T-Box according to any one of claims 1 to 6, characterized in that: The first control signal terminal (M1) includes a first gain control signal terminal (UART1) and a first transceiver control signal terminal (TX-EN1).

8. The T-Box according to claim 7, characterized in that: The second branch (2) also includes a first controller (62), which is configured to output a first gain control signal (uart1) to the first gain control signal terminal (UART1) after receiving the transceiver control signal (tx-en) from the first transceiver control signal terminal (TX-EN1).

9. The T-Box according to claim 7 or 8, characterized in that: The first controller (62) is coupled to the first gain control signal terminal (UART1) and the first transceiver control signal terminal (TX-EN1), and the V2X circuit (61) is coupled to the first transceiver control signal terminal (TX-EN1).

10. The T-Box according to any one of claims 7 to 9, characterized in that: The second branch (2) further comprises a modulation circuit (70); The input end of the modulation circuit (70) is coupled to the first gain control signal end (UART1) and the first transceiver control signal end (TX-EN1), and the output end of the modulation circuit (70) is coupled to the first radio frequency isolation circuit (21).

11. The T-Box according to claim 10, characterized in that: The second branch (2) further comprises a carrier circuit (64), wherein the carrier circuit (64) is used to output a carrier signal; the carrier circuit (64) is coupled to an input end of the modulation circuit (70).

12. A relay, characterized in that: include: A fourth branch (4) comprises a vehicle-to-anything (V2X) signal terminal and a bidirectional switch circuit (13), wherein the bidirectional switch circuit (13) comprises a first path (L1) and a second path (L2) coupled in parallel between the V2X signal terminal and a third junction point (Q3), wherein the first path (L1) comprises a first power amplifier (PA1), and an output terminal of the first power amplifier (PA1) is coupled to the V2X signal terminal; and the V2X signal terminal is used to send and receive radio frequency signals; The fifth branch (5) comprises a second control signal terminal (M2) and a second radio frequency isolation circuit (22), wherein the second control signal terminal (M2) is coupled to the bidirectional switch circuit (13); the second radio frequency isolation circuit (22) is coupled between the second control signal terminal (M2) and the third junction point (Q3); the second control signal terminal (M2) is used to receive a control signal; and the second radio frequency isolation circuit (22) is used to pass the control signal and isolate the radio frequency signal.

13. The relay according to claim 12, characterized in that: The second control signal terminal (M2) includes a second gain control signal terminal (UART2) and a second transceiver control signal terminal (TX-EN2); the second gain control signal terminal (UART2) is coupled to the first power amplifier (PA1), and the second transceiver control signal terminal (TX-EN2) is coupled to the first path (L1) and the second path (L2), respectively.

14. The relay according to claim 13, characterized in that: The fifth branch (5) further includes a second controller (65) and a first frequency band blocking circuit (71); The first frequency band blocking circuit (71) is coupled between the second transceiver control signal terminal (TX-EN2) and a second node (P2), and the second node (P2) is coupled to the second radio frequency isolation circuit (22); The second controller (65) is configured to output a second gain control signal (uart2) to the second gain control signal terminal (UART2) after receiving the transceiver control signal (tx-en) of the second transceiver control signal terminal (TX-EN2) and the control signal of the second node (P2).

15. The relay according to claim 14, characterized in that: The output end of the second controller (65) is coupled to the second gain control signal end (UART2), and the input end of the second controller (65) is coupled to the second transceiver control signal end (TX-EN2) and the second node (P2).

16. The relay according to claim 14 or 15, characterized in that: The fifth branch (5) further includes a second frequency band blocking circuit (72), wherein the second frequency band blocking circuit (72) is coupled between the second node (P2) and the second radio frequency isolation circuit (22).

17. The relay according to any one of claims 14 to 16, characterized in that: The fifth branch (5) further includes a first signal enhancement circuit (90), wherein the first signal enhancement circuit (90) is coupled between the second controller (65) and the second node (P2); and / or, The fifth branch (5) further includes a second signal enhancement circuit, wherein the second signal enhancement circuit is coupled between the second controller (65) and the second transceiver control signal terminal (TX-EN2); and / or, The fifth branch (5) further includes a third signal enhancement circuit, and the third signal enhancement circuit is coupled between the second node (P2) and the second radio frequency isolation circuit (22).

18. The relay according to any one of claims 14 to 17, characterized in that: The relay also includes a power detector (99), which is coupled to the input end of the second controller (65) and the third junction (Q3) respectively. The second controller (65) is also configured to receive a power signal sent by the power detector before outputting a second gain control signal (uart2) to the second gain control signal end (UART2).

19. The relay according to any one of claims 12 to 18, characterized in that: The second radio frequency isolation circuit (22) comprises a (1 / 4+N / 2)λ transmission line (X); a first end of the (1 / 4+N / 2)λ transmission line (X) is coupled to the third junction (Q3), a second end of the (1 / 4+N / 2)λ transmission line (X) is coupled to a third node (P3); the third node (P3) is coupled to the second control signal terminal (M2); Wherein, λ is the wavelength of the radio frequency signal, and N is an integer greater than or equal to 0.

20. The relay according to claim 19, characterized in that: The second radio frequency isolation circuit (22) further includes a third capacitor (C7) and a fourth capacitor (C8); The first end of the third capacitor (C7) and the first end of the fourth capacitor (C8) are both coupled to the reference ground voltage terminal (GND), and the second end of the third capacitor (C7) and the second end of the fourth capacitor (C8) are both coupled to the third node (P3).

21. The relay according to any one of claims 12 to 20, characterized in that: The second path (L2) includes a second power amplifier (PA2).

22. The relay according to any one of claims 12 to 21, characterized in that: The relay further comprises a sixth branch (6); The sixth branch (6) comprises a second power supply circuit (66), the second power supply circuit (66) is coupled to a fourth junction point (Q4), and the fourth junction point (Q4) is located between the second radio frequency isolation circuit (22) and the second control signal terminal (M2).

23. The relay according to claim 22, characterized in that: The fourth branch (4) further comprises a second radio frequency conduction circuit (12), wherein the second radio frequency conduction circuit (12) is coupled between the bidirectional switch circuit (13) and the third junction point (Q3); and / or, The fourth branch (4) further comprises a third AC-passing and DC-isolating circuit (42), wherein the third AC-passing and DC-isolating circuit (42) is coupled between the bidirectional switch circuit (13) and the third junction point (Q3); and / or, The fifth branch (5) further comprises a fourth AC-passing and DC-isolating circuit (52), wherein the fourth AC-passing and DC-isolating circuit (52) is coupled between the second control signal terminal (M2) and the fourth combining point (Q4); and / or, The sixth branch (6) further comprises a second direct current-passing and alternating current-isolating circuit (32), wherein the second direct current-passing and alternating current-isolating circuit (32) is coupled between the second power supply circuit (66) and the fourth junction point (Q4).

24. A signal transmission system, characterized in that: It comprises the T-Box described in any one of claims 1 to 11, a cable, and the relay described in any one of claims 12 to 23; one end of the cable is coupled to the first combining point (Q1) of the T-Box, and the other end of the cable is coupled to the third combining point (Q3) of the relay.

25. A vehicle, characterized in that: The invention comprises an antenna and the signal transmission system as claimed in claim 24, wherein the signal transmission system is coupled to the antenna.

Images