Digital car key system
By deploying distance measurement and communication nodes using StarFlash technology in the car's center console and doors, combined with time-division duplex mechanism and high-frequency adaptive frequency hopping, the problems of low accuracy, poor security, and insufficient stability of digital car key systems are solved, realizing a high-precision, high-security, and high-stability digital car key system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-21
- Publication Date
- 2026-03-31
AI Technical Summary
Existing digital car key systems suffer from low accuracy, poor security, and insufficient stability. In particular, signals are easily interfered with in complex environments, affecting the user experience.
Starlight technology is used to deploy ranging and communication nodes in the car's center console and door positions. Wireless data transmission is achieved through the Starlight protocol. Combined with time-division duplex mechanism and high-frequency band adaptive frequency hopping mechanism, the physical wiring harness in the vehicle is reduced, multi-path redundant transmission is supported, and high-frequency noise is suppressed and signal quality is improved through independent digitally controlled regulated power supply and filter circuit.
A high-precision, high-security, and high-stability digital car key system has been implemented, with a response latency of less than 10ms, improving user convenience and vehicle security.
Smart Images
Figure CN224068797U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of automotive key technology, specifically to a digital car key system. Background Technology
[0002] In the development of car key technology, traditional physical keys are gradually transforming into digital car keys. Digital car keys allow car owners to unlock and operate their vehicles using smartphones or wearable devices. Currently, mainstream Bluetooth digital car keys have revealed several problems in practical applications: during vehicle unlocking and starting, connection failures or delayed responses often occur due to inaccurate distance judgment; security vulnerabilities exist, making them susceptible to "relay attacks" and exposing vehicles to theft risks; stability is insufficient, with signals easily interfered with in complex environments, causing frequent abnormal door opening and closing, severely impacting user experience. While Ultra Wide Band (UWB) technology has certain advantages in positioning accuracy, it cannot function independently and requires Bluetooth assistance. Furthermore, it suffers from drawbacks such as narrow coverage, rapid signal attenuation, and excessive power consumption, limiting its large-scale application. Utility Model Content
[0003] The present invention aims to solve the problems of low accuracy, poor security and insufficient stability of existing digital car keys, and provides a digital car key system.
[0004] To solve the above problems, this utility model is achieved through the following technical solution:
[0005] A digital car key system includes a user terminal device and an in-vehicle terminal device; the user terminal device is held by the user and includes a user voltage regulator and a user control module; the in-vehicle terminal device is installed inside the car and includes an in-vehicle voltage regulator, an in-vehicle main control module and two or more in-vehicle execution modules.
[0006] The user control module consists of a user microcontroller, a user communication filter circuit, a user communication pull-up resistor, a user satellite communication circuit, a user ranging filter circuit, a user ranging pull-up resistor, a user satellite ranging circuit, and a touch screen. The user regulated power supply is connected to the power supply terminal of the user satellite communication circuit through the user communication filter circuit, and also to the power supply terminal of the user satellite ranging circuit through the user ranging filter circuit. The user regulated power supply is directly connected to the power supply terminals of the user microcontroller and the touch screen. The user microcontroller is connected to the user satellite communication circuit through the user communication pull-up resistor, and also to the user satellite ranging circuit through the user ranging pull-up resistor. The user microcontroller is directly connected to the touch screen.
[0007] The vehicle-mounted main control module is installed in the center console of the car. It consists of a main control microcontroller, a main control communication filter circuit, a main control communication pull-up resistor, a main control star-flash communication circuit, a main control ranging filter circuit, a main control ranging pull-up resistor, a main control star-flash ranging circuit, and a serial port conversion circuit. The vehicle-mounted regulated power supply is connected to the power supply terminal of the main control star-flash communication circuit through the main control communication filter circuit, and to the power supply terminal of the main control star-flash ranging circuit through the main control ranging filter circuit. The vehicle-mounted regulated power supply is also directly connected to the power supply terminals of the main control microcontroller and the serial port conversion circuit. The main control microcontroller is connected to the main control star-flash communication circuit through the main control communication pull-up resistor, and to the main control star-flash ranging circuit through the main control ranging pull-up resistor. Finally, the main control microcontroller is connected to the USB interface of the car's center console through the serial port conversion circuit.
[0008] The number of vehicle-mounted actuator modules is the same as the number of car doors, with each module installed at the corresponding door. Each module consists of an actuator microcontroller, an actuator communication filter circuit, an actuator communication pull-up resistor, an actuator star-flash communication circuit, an actuator ranging filter circuit, an actuator ranging pull-up resistor, an actuator star-flash ranging circuit, and two interface circuits. The vehicle-mounted regulated power supply is connected to the power supply terminal of the actuator star-flash communication circuit through the actuator communication filter circuit, and to the power supply terminal of the actuator star-flash ranging circuit through the actuator ranging filter circuit. The regulated power supply is also directly connected to the power supply terminals of the actuator microcontroller and the two interface circuits. The actuator microcontroller is connected to the actuator star-flash communication circuit through the actuator communication pull-up resistor, and to the actuator star-flash ranging circuit through the actuator ranging pull-up resistor. The actuator microcontroller is connected to the corresponding door's switch servo motor through one interface circuit and to the corresponding door's motor through another interface circuit.
[0009] The user star-flash communication circuit of the user control module is wirelessly connected to the main control star-flash communication circuit of the vehicle main control module. The main control star-flash communication circuit of the vehicle main control module is wirelessly connected to the execution star-flash communication circuits of each vehicle execution module. The user star-flash ranging circuit of the user control module is wirelessly connected to the main control star-flash ranging circuit of the vehicle main control module and the execution star-flash ranging circuit of the vehicle execution module.
[0010] In the above scheme, the user's voltage regulator is powered by a built-in lithium battery, and the vehicle's voltage regulator is powered by the vehicle's battery.
[0011] In the above solution, a UPS uninterruptible power supply is installed between the vehicle-mounted voltage regulator and the vehicle-mounted battery.
[0012] In the above scheme, the serial port conversion circuit of the vehicle main control module is a USB-TTL serial port conversion circuit.
[0013] In the above scheme, both interface circuits of the vehicle-mounted execution module are UPIO interface circuits.
[0014] Compared with the prior art, this utility model has the following characteristics:
[0015] 1. Deploy StarFlash ranging nodes and communication nodes in the center console and door positions of the car to realize wireless data transmission by replacing the CAN bus with StarFlash technology, and wirelessly interact with the vehicle controller in the center console through the StarFlash protocol. This not only reduces the physical wiring harness in the car and optimizes the vehicle terminal architecture, but also allows new functional nodes to be added without rewiring and directly access the system through wireless networking.
[0016] 2. On the one hand, the StarFlash communication module and the StarFlash ranging module adopt a time-division duplex (TDD) mechanism, and the communication and positioning data are transmitted through different time slots to avoid signal conflicts; on the other hand, the StarFlash technology adopts a high-frequency band (such as 5.8GHz) and an adaptive frequency hopping mechanism to avoid electromagnetic interference in the vehicle, and supports multi-path redundant transmission to ensure the real-time performance of key commands such as door control (response delay <10ms).
[0017] 3. The internal circuit architectures of the user control module, the vehicle main control module, and the vehicle execution module are similar, and the internal circuits are connected through standardized interfaces, supporting hot-swappable replacement, thereby simplifying the design by making each module replaceable.
[0018] 4. Both the user-end equipment and the vehicle-mounted equipment are equipped with independent digitally controlled regulated power supplies, supporting 3.3V / 5V dual voltage output. Power supply is controlled by a physical switch to ensure that a single node failure does not affect the overall system. At the same time, the Star Flash circuit (Star Flash communication circuit and Star Flash ranging circuit) and the regulated power supply are filtered by a filter circuit to suppress high-frequency noise.
[0019] 5. A 4.7kΩ pull-up resistor is integrated between the Star Flash circuit (Star Flash communication circuit and Star Flash ranging circuit) and the serial port connection of the microcontroller. It is pulled up by default when idle to prevent jitter and improve signal quality. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of a digital car key system.
[0021] Figure 2 This is a schematic diagram of the user control module.
[0022] Figure 3 This is a schematic diagram of the vehicle-mounted main control module.
[0023] Figure 4 This is a schematic diagram of the vehicle-mounted execution module. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific examples and accompanying drawings.
[0025] See Figure 1 A digital car key system comprises a user terminal device and an in-vehicle terminal device. The user terminal device is handheld and includes a user power supply and a user control module. The in-vehicle terminal device is installed inside the vehicle and includes an in-vehicle power supply, an in-vehicle main control module, and multiple in-vehicle execution modules. The user power supply is powered by a built-in lithium battery. The user power supply uses a rechargeable lithium battery and a matching power driver chip IR2104 to provide a stable power supply for the entire user terminal device, while also featuring low-power management, automatically entering a low-power mode when the device is idle. The in-vehicle power supply is powered by the vehicle's battery. To prevent power outages, a UPS (Uninterruptible Power Supply) is installed between the in-vehicle power supply and the in-vehicle battery.
[0026] See Figure 2 The user control module consists of a user microcontroller, a user communication filter circuit, a user communication pull-up resistor, a user satellite communication circuit, a user ranging filter circuit, a user ranging pull-up resistor, a user satellite ranging circuit, and a touch screen. The user regulated power supply is connected to the power supply terminal of the user satellite communication circuit through the user communication filter circuit, and to the power supply terminal of the user satellite ranging circuit through the user ranging filter circuit. The user regulated power supply is also directly connected to the power supply terminals of the user microcontroller and the touch screen. The user microcontroller is connected to the user satellite communication circuit through the user communication pull-up resistor, and to the user satellite ranging circuit through the user ranging pull-up resistor. The user microcontroller is also directly connected to the touch screen.
[0027] See Figure 3 The vehicle-mounted main control module is installed in the center console of the car. It consists of a main control microcontroller, a main control communication filter circuit, a main control communication pull-up resistor, a main control satellite communication circuit, a main control ranging filter circuit, a main control ranging pull-up resistor, a main control satellite ranging circuit, and a serial port conversion circuit. The serial port conversion circuit is a USB-TTL serial port conversion circuit. The vehicle-mounted regulated power supply is connected to the power supply terminal of the main control satellite communication circuit through the main control communication filter circuit, and to the power supply terminal of the main control satellite ranging circuit through the main control ranging filter circuit. The vehicle-mounted regulated power supply is also directly connected to the power supply terminals of the main control microcontroller and the serial port conversion circuit. The main control microcontroller is connected to the main control satellite communication circuit through the main control communication pull-up resistor, and to the main control satellite ranging circuit through the main control ranging pull-up resistor. Finally, the main control microcontroller is connected to the USB interface on the car's center console through the serial port conversion circuit.
[0028] See Figure 4The number of on-board actuators is the same as the number of car doors, with each actuator installed in the corresponding car door. Each actuator module consists of an actuator microcontroller, an actuator communication filter circuit, an actuator communication pull-up resistor, an actuator star-flash communication circuit, an actuator ranging filter circuit, an actuator ranging pull-up resistor, an actuator star-flash ranging circuit, and two interface circuits. Both interface circuits are UPIO interface circuits. The on-board regulated power supply is connected to the power supply terminal of the actuator star-flash communication circuit through the actuator communication filter circuit, and to the power supply terminal of the actuator star-flash ranging circuit through the actuator ranging filter circuit. The on-board regulated power supply is also directly connected to the power supply terminals of the actuator microcontroller and the two interface circuits. The actuator microcontroller is connected to the actuator star-flash communication circuit through the actuator communication pull-up resistor, and to the actuator star-flash ranging circuit through the actuator ranging pull-up resistor. The actuator microcontroller is connected to the corresponding door's switch servo motor through one interface circuit and to the corresponding door's motor through the other interface circuit.
[0029] The user microcontroller uses an STM32F103 series MCU (64KB Flash), the main control microcontroller uses an NXPS32K144 (automotive grade) MCU, and the execution microcontroller uses an STM32 series MCU (64KB Flash). By streamlining resources, the complexity of simulation testing is reduced, and development costs are reduced by 40%. The user Star Flash communication circuit, the main control Star Flash communication circuit, and the execution Star Flash communication circuit all use the Hi3863 chip that conforms to the Star Flash technology standard or the BearPi BM-H63 module equipped with the Star Flash chip.
[0030] The user control module's user star-flash communication circuit is wirelessly connected to the vehicle main control module's main control star-flash communication circuit for wireless data exchange. The vehicle main control module's main control star-flash communication circuit is also wirelessly connected to the execution star-flash communication circuits of each vehicle execution module for wireless data exchange. The vehicle main control module is responsible for receiving star-flash signals from the user control module, parsing and verifying the received signals, and then sending star-flash signals to the vehicle execution modules to control functions such as vehicle location, unlocking, and locking.
[0031] The user-controlled satellite ranging circuit of the user control module is wirelessly connected to the main control satellite ranging circuit of the vehicle main control module and the execution satellite ranging circuit of the vehicle execution module. The user control module sends satellite ranging signals to the vehicle main control module and the vehicle execution module through the satellite ranging circuit. The vehicle main control module and the vehicle execution module return satellite ranging signals through the satellite ranging circuit. The user control module obtains the specific planar or spatial coordinates with the geometric center of the vehicle as the origin by existing satellite positioning algorithms (such as hyperbolic positioning or trilateration), thereby realizing positioning and navigation functions.
[0032] The working process of this utility model is as follows:
[0033] Users select the operating mode via the touchscreen display on the user control module. These modes include vehicle location mode, unlock mode, and lock mode. In unlock mode, users need to select the specific door to unlock. In lock mode, all doors are locked by default.
[0034] When the vehicle search mode is selected, the user microcontroller of the user control module receives a signal from the touch screen and enters the vehicle search mode. At this time, the user microcontroller controls the user star-flash ranging circuit to send ranging signals to the main control star-flash ranging circuit of the vehicle main control module and the execution star-flash ranging circuits of all vehicle execution modules. The main control star-flash ranging circuit of the vehicle main control module and the execution star-flash ranging circuits of all vehicle execution modules send their ranging beacons back to the user microcontroller of the user control module. The user microcontroller calculates the distance between the user and the vehicle based on all the returned ranging beacons and its own ranging beacon.
[0035] When the unlock mode is selected, the user microcontroller of the user control module receives a signal from the touch screen and enters the unlock mode. At this time, the user microcontroller of the user control module controls the user star flash communication circuit to communicate with the main control star flash communication circuit of the vehicle main control module. The main control star flash communication circuit of the vehicle main control module then sends an unlock signal to the vehicle star flash communication circuit of the corresponding vehicle execution module. The execution microcontroller of the corresponding vehicle execution module then controls the servo motor of its corresponding door to open the door.
[0036] When the vehicle locking mode is selected, the user microcontroller of the user control module receives a signal from the touch screen and enters the vehicle locking mode. At this time, the user microcontroller of the user control module controls the user star flash communication circuit to communicate with the main control star flash communication circuit of the vehicle main control module. The main control star flash communication circuit of the vehicle main control module then sends a locking signal to the vehicle star flash communication circuits of all vehicle execution modules. The execution microcontrollers of all vehicle execution modules control the electrodes of their corresponding doors to lock the doors.
[0037] This invention utilizes the advantages of star-flash technology to achieve a high-precision, high-security, high-stability, and low-power digital car key system, thereby improving user convenience and vehicle security.
[0038] It should be noted that although the embodiments described above are illustrative, they are not intended to limit the present invention. Therefore, the present invention is not limited to the specific embodiments described above. Any other embodiments obtained by those skilled in the art under the guidance of the present invention without departing from its principles are considered to be within the protection scope of the present invention.
Claims
1. A digital car key system, characterized in that, It comprises a user terminal device and a vehicle terminal device; the user terminal device is handheld by the user, which comprises a user voltage stabilizer and a user control module; The vehicle terminal device is installed in the car, which comprises a vehicle voltage stabilizer, a vehicle main control module and more than two vehicle execution modules; The user control module is composed of a user microcontroller, a user communication filter circuit, a user communication pull-up resistor, a user star flash communication circuit, a user ranging filter circuit, a user ranging pull-up resistor, a user star flash ranging circuit and a touch display screen; the user voltage stabilizer is connected with the power supply end of the user star flash communication circuit through the user communication filter circuit, and is connected with the power supply end of the user star flash ranging circuit through the user ranging filter circuit; the user voltage stabilizer is directly connected with the power supply end of the user microcontroller and the touch display screen; the user microcontroller is connected with the user star flash communication circuit through the user communication pull-up resistor, and is connected with the user star flash ranging circuit through the user ranging pull-up resistor; the user microcontroller is directly connected with the touch display screen; The vehicle main control module is installed in the center console of the car; the vehicle main control module is composed of a main control microcontroller, a main control communication filter circuit, a main control communication pull-up resistor, a main control star flash communication circuit, a main control ranging filter circuit, a main control ranging pull-up resistor, a main control star flash ranging circuit and a serial port conversion circuit; the vehicle voltage stabilizer is connected with the power supply end of the main control star flash communication circuit through the main control communication filter circuit, and is connected with the power supply end of the main control star flash ranging circuit through the main control ranging filter circuit; the vehicle voltage stabilizer is directly connected with the power supply end of the main control microcontroller and the serial port conversion circuit; the main control microcontroller is connected with the main control star flash communication circuit through the main control communication pull-up resistor, and is connected with the main control star flash ranging circuit through the main control ranging pull-up resistor; the main control microcontroller is connected with the USB interface of the center console of the car through the serial port conversion circuit; The number of vehicle execution modules is the same as the number of car doors, and each vehicle execution module is installed at the corresponding car door of the car; each vehicle execution module is composed of an execution microcontroller, an execution communication filter circuit, an execution communication pull-up resistor, an execution star flash communication circuit, an execution ranging filter circuit, an execution ranging pull-up resistor, an execution star flash ranging circuit and two interface circuits; the vehicle voltage stabilizer is connected with the power supply end of the execution star flash communication circuit through the execution communication filter circuit, and is connected with the power supply end of the execution star flash ranging circuit through the execution ranging filter circuit; the vehicle voltage stabilizer is directly connected with the power supply end of the execution microcontroller and the two interface circuits; the execution microcontroller is connected with the execution star flash communication circuit through the execution communication pull-up resistor, and is connected with the execution star flash ranging circuit through the execution ranging pull-up resistor; the execution microcontroller is connected with the switch steering engine of the corresponding car door through one interface circuit, and is connected with the motor of the corresponding car door through the other interface circuit. The user star flash communication circuit of the user control module is wirelessly connected with the master control star flash communication circuit of the vehicle-mounted master control module, and the master control star flash communication circuit of the vehicle-mounted master control module is wirelessly connected with the execution star flash communication circuit of each vehicle-mounted execution module; the user star flash distance measurement circuit of the user control module is wirelessly connected with the master control star flash distance measurement circuit of the vehicle-mounted master control module and the execution star flash distance measurement circuit of the vehicle-mounted execution module.
2. A digital key system according to claim 1, characterized in that The user voltage stabilizing power supply is powered by a built-in lithium battery, and the vehicle-mounted voltage stabilizing power supply is powered by a vehicle-mounted battery.
3. A digital key system according to claim 2, characterized in that A UPS uninterrupted power supply is arranged between the vehicle-mounted voltage stabilizing power supply and the vehicle-mounted battery.
4. The digital key system of claim 1, wherein the digital key system further comprises a second communication module configured to communicate with the second electronic device. The serial port conversion circuit of the vehicle-mounted master control module is a USB-TTL serial port conversion circuit.
5. The digital key system of claim 1, wherein the digital key system further comprises a server configured to store the encrypted key data and the encrypted key data is transmitted to the server. The two interface circuits of the vehicle-mounted execution module are UPIO interface circuits.