Energy transmission and signal transmission method of passive wireless lock

Abstract

According to the energy transmission and signal transmission method of the passive wireless lock, energy is sent in a discontinuous pulse mode, the power supply function is achieved, signal transmission is achieved through time sequence coding of pulses, and through the pulse coding mechanism, the signal transmission efficiency is improved. Energy transmission and signal transmission do not need independent hardware modules any more, the system design is simplified, the transmission efficiency is also improved, and the method comprises the following steps that S1, pulse type energy transmission and a time coding mechanism are adopted for signal transmission; s2, setting a synchronization and decoding mechanism of signal transmission; s3, integrated design of energy transmission and signal transmission; s4, the anti-interference capability in the transmission process is improved; and S5, improving the system safety.

Description

Technical Field

[0001] The present invention relates to the field of wireless lock technology, and in particular to a method for energy transmission and signal transmission of a passive wireless lock. In particular, the method is directed to energy transmission and signal transmission in the field of commodity display and anti-theft. The method realizes power supply and data communication of the passive lock by wireless means, and is applicable to systems such as anti-theft display cabinets and smart door locks. Background Art

[0002] In the fields of commodity display anti-theft, smart door locks, etc., passive locks, as a lock that does not require a built-in power supply, have been widely used due to their simple structure, easy use, and low cost. Passive locks usually rely on external devices (such as keys, controllers) for power supply and unlocking, and are mainly used in scenarios that require low power consumption, high stability, and low maintenance costs, such as anti-theft display cabinets, smart access control systems, safes, etc.

[0003] In the prior art, energy transmission and signal transmission solutions of passive locks are mainly divided into two categories: contact transmission and wireless transmission.

[0004] 1. Contact energy and signal transmission:

[0005] In traditional passive locks, contact energy transmission is more common. This solution powers the passive lock from the key or controller end through a physical contact point (such as a metal interface) and transmits an unlocking signal at the same time. Its working principle is usually to contact the metal pins on the key with the metal contacts on the lock, the power supply on the key end powers the lock through the contact point, and the unlocking signal is transmitted to the lock through the same interface.

[0006] The advantages of this contact transmission technology are:

[0007] High efficiency of power transmission: Due to physical contact, energy loss is small and power supply efficiency is high.

[0008] Stable signal transmission: Signals are transmitted through physical conductors, with less signal interference and better transmission stability.

[0009] However, contact transmission also has significant disadvantages:

[0010] Contact points are prone to wear: With increasing use, metal interfaces are prone to wear, resulting in poor contact and affecting the stability of power supply and signal transmission.

[0011] Susceptible to environmental influences: In humid, dusty or corrosive environments, the contact points are easily contaminated or oxidized, which in turn affects the transmission effect.

[0012] High maintenance cost: Due to wear and damage of contact points, the equipment needs frequent maintenance and replacement, which increases the cost of use.

[0013] 2. Wireless energy and signal transmission:

[0014] With the development of wireless technology, passive locks have gradually adopted wireless energy transmission and wireless signal transmission solutions in recent years. Wireless energy transmission uses technologies such as inductive coupling and magnetic resonance to transmit electrical energy from the key or controller to the passive lock through electromagnetic waves. Wireless signal transmission usually transmits unlocking signals through wireless communication protocols such as Bluetooth, RFID, and NFC.

[0015] The advantages of wireless transmission technology are:

[0016] Reduce physical wear: Since there is no need for physical contact, the wear problem of metal interfaces is avoided, which increases the service life of the equipment.

[0017] Easy to use: Wireless transmission improves the convenience of use, especially in scenarios where docking is difficult. Users only need to bring the key close to the lock to complete the power supply and unlocking operations.

[0018] However, wireless transmission also has some technical bottlenecks:

[0019] High system cost: Wireless transmission requires the key's energy and signal to be transmitted to the lock. The lock performs password matching judgment on the signal on the premise of obtaining energy, and performs the unlocking operation under the condition of password matching. It requires two modules, wireless energy transmission and wireless signal transmission, resulting in high hardware costs.

[0020] High system complexity: Existing wireless transmission systems usually need to handle the transmission of energy and signals separately, which leads to complex hardware and software design of the system and high manufacturing costs.

[0021] Signal interference problem: Wireless signal transmission is easily interfered by the external environment, such as electromagnetic wave interference, metal shielding, etc., especially the high-frequency electromagnetic field interference of wireless energy transmission itself, resulting in unstable unlocking signal. Especially in complex environments, there may be signal delays or loss.

[0022] However, both the contact transmission and wireless transmission of the existing technology have limitations: 1. Separation of energy and signal transmission methods: The existing wireless transmission system usually separates energy transmission from signal transmission, which increases the complexity of the system. Two independent transmission modules are required, one for wireless power supply and the other for signal transmission. The system is not only complex in design and high in manufacturing cost, but also difficult to avoid interference between the two. 2. Poor synchronization of energy and signal: Since two independent modules are used to transmit energy and signal respectively, the signal received by the key is difficult to synchronize with the energy. If the signal is received earlier than the energy, the lock cannot process the signal because it is not powered. If the signal is received later than the energy, the lock needs to be charged for a long time, resulting in a decrease in the energy utilization rate of the key. 3. Poor system stability: Since wireless transmission is susceptible to environmental interference, especially in scenarios with strong electromagnetic interference of similar frequencies and more metal shielding, the stability and accuracy of signal transmission are difficult to guarantee, affecting the user experience and the reliability of the device. 4. High maintenance cost: Although the contact transmission solution is stable, it requires regular maintenance or replacement due to wear and contamination of the contact points, which increases operating costs. Summary of the invention

[0023] In view of the defects existing in the prior art, the technical problem solved by the present invention is: there are many problems in the prior art regarding the energy transmission and signal transmission methods of passive locks, such as complex system, separation of energy and signal transmission, and susceptibility of signals to interference, etc., and a method for energy transmission and signal transmission of a passive wireless lock is provided, which can improve the synchronization of energy and signal transmission, enhance the stability of signal transmission, and improve the durability of the equipment while reducing system complexity and manufacturing cost.

[0024] To achieve the above objectives, the present invention provides:

[0025] A method for energy transmission and signal transmission of a passive wireless lock, comprising the following steps:

[0026] S1: Insert the key into the lock, press the key button, start the energy sending module, and monitor the current value output by the key power supply to the energy sending module;

[0027] The current value when the key is pressed without being inserted into the keyhole is I N , the maximum current when the key is pressed when inserted into the keyhole is I max , in I max After delay t s , (t s The current value is I L .

[0028] If I max <1.5*I N, indicating that the key is not correctly inserted into the lock, and an alarm signal is issued through the key;

[0029] If I L >1.2*I N , indicating that the energy receiving module of the lock is overloaded, and an alarm signal is sent through the key;

[0030] If I max ≥1.5*I N And I L ≤1.2*I N , indicating that the lock's energy receiving module is working properly;

[0031] S2: When the energy receiving module of the lock is normal, the continuous power supply of the energy sending module is changed to pulse power supply. The pulse is generated by the switch between the power supply and the energy sending module controlled by the signal encoding module (the switch is a MOS tube). The continuous cycle and change rule of the high level and low level of the pulse represent the sent unlocking password, that is, the sent unlocking password is superimposed in the wireless energy transmission process;

[0032] A high level that lasts for more than 0.5s is used as the start and end signals. After the start and end signals, a low level that lasts for 0.1s is used, and then a high level of 0.1s to 0.4s is used as the information code, representing 0 to 3 respectively. Each information code is separated by a low level that lasts for 0.1s. Multiple information codes constitute an unlocking password in a quaternary format. After the unlocking password is completed, a low level that lasts for 0.1s is used, and then a high level that lasts for more than 0.5s is used as the start and end signals. The unlocking password is generated cyclically and sent in a superimposed manner through the wireless energy transmission process.

[0033] S3: When the energy receiving module of the lock is normal, the energy signal received by the energy receiving module is sent to the signal decoding module through the RC low-pass filter, and then charged to the energy storage capacitor through the diode;

[0034] S4: The signal decoding module records the duration of each high level and forms an array [N1, N2, ..., N n ], unit is ms;

[0035] Judge the values ​​in the array one by one from the beginning. If N k (k=1,2,…,n) is greater than 450, then from N k+1 Start taking numbers, assuming that N k+1 Afterwards, N m (m=k+2,k+3,…,n) is the first number greater than 450, then the received unlock password is [N k+1 ,N k+2 ,…,N m-1 ].

[0036] Perform unlock calculation, assuming that the built-in unlock password of the lock is [X1,X2,…,X p ](Each number has a value of 0 to 3). If the length of the received unlock password is not equal to the length of the built-in unlock password, it is considered that the unlocking has failed. If the length of the received unlock password is equal to the length of the built-in unlock password, the passwords are compared:

[0037] [dX1,dX2,…,dX p ]=[X1,X2,X3,…,X p ]*100-[N k+1 ,N k+2 ,…,N m-1 ]+100

[0038] Calculate [dX1, dX2, dX3, …, dX p ] If the RMS is less than or equal to 10, it indicates that the unlocking is successful. If the RMS is greater than 10, it indicates that the unlocking fails.

[0039] After the unlock fails, m+1 Start to obtain data again, form a new received unlocking password, and perform unlocking calculation again.

[0040] If the unlocking fails for 3 to 5 times in a row (determined by the user), the lock will send out an alarm signal, and the unlocking ends. The signal decoding module will no longer decode. It will not be able to decode again until the key is removed, the lock is disconnected and recharged.

[0041] S5: On the premise of successful unlocking, the signal decoding module controls the switch between the energy storage capacitor and the load (the switch is a MOS tube) to turn on, the load is energized, the unlocking mechanism is activated, the lock is opened, and the lock sends a successful unlocking signal.

[0042] S6: After step S2, monitor the current value output by the key power supply to the energy transmission module. When the maximum current value I max2 ≥I max , it indicates that the unlocking is successful, and the key records the unlocking success information; otherwise, it indicates that the unlocking fails, and the key records the unlocking failure information.

[0043] Preferably, in S1, the key end sends energy, and the key end sends intermittent pulse energy through a wireless transmission module according to a set time coding rule;

[0044] Preferably, in S1, each pulse has a different duration, representing different binary information, a long pulse of 0.1s represents "1", and a short pulse of 0.05s represents "0".

[0045] Preferably, in S1, when the transmission starts and ends, the key end sends a long pulse lasting more than 0.5s, indicating the start and end of the signal transmission.

[0046] Preferably, in S2, after receiving the pulse energy, the wireless receiving module at the lock end first enters a synchronization state and identifies the starting pulse of the transmission.

[0047] Preferably, in S2, the lock monitors the duration of each pulse in real time through an internal decoding circuit, and decodes it into a corresponding binary signal.

[0048] Preferably, in S2, after decoding is completed, the control circuit inside the lock verifies the signal to ensure the integrity and accuracy of the signal.

[0049] Preferably, in S3, energy transmission and signal transmission are integrated into one wireless transmission path.

[0050] Preferably, in S4, a low-power, high-frequency wireless transmission band is used to reduce electromagnetic interference in daily environment;

[0051] Dynamic frequency adjustment: During signal transmission, the system can dynamically adjust the transmission frequency according to environmental conditions to avoid interference frequency segments and ensure the stability of signal transmission;

[0052] Redundant design: During signal transmission, redundant codes and check codes are added to ensure accurate signal decoding and transmission reliability.

[0053] Preferably, in S5, dynamic encryption is used: during each transmission of the unlocking signal, a dynamic encryption algorithm is used to ensure the uniqueness and timeliness of the signal and prevent signal replay attacks;

[0054] Two-way authentication is adopted: the key end and the lock end perform two-way authentication before signal transmission to ensure that energy and signal transmission can only be carried out after the identity authentication of both parties is passed.

[0055] Compared with the prior art, the advantages of the present invention are:

[0056] 1. Simplify system design and reduce manufacturing costs:

[0057] In the prior art, energy transmission and signal transmission are usually carried out through two independent modules, which increases the complexity of the system and the manufacturing cost. The first goal of the present invention is to integrate energy transmission and signal transmission into one system through innovative design, reduce the number of transmission modules, and thus simplify the system design. Through the integrated design scheme, the manufacturing cost is reduced, and the volume of the system is reduced, making the device more compact and lightweight.

[0058] 2. Improve energy transmission efficiency:

[0059] The existing wireless energy transmission technology has low energy conversion efficiency, resulting in a slow power supply speed for passive locks, which affects the user experience. The second objective of the present invention is to improve the energy transmission efficiency and reduce energy loss by optimizing the wireless energy transmission method, such as using efficient magnetic resonance technology or inductive coupling technology. By improving the energy transmission efficiency and shortening the power supply time, the passive lock can obtain sufficient power more quickly, thereby improving the response speed of the entire system.

[0060] 3. Improve the stability and anti-interference ability of signal transmission:

[0061] Wireless signal transmission technologies (such as Bluetooth, RFID, NFC, etc.) are easily affected by electromagnetic interference or metal shielding in complex environments, resulting in unstable signal transmission and affecting the accuracy of unlocking. The third goal of the present invention is to improve the stability and anti-interference ability of signal transmission by optimizing the signal transmission path and protocol. Whether in a strong electromagnetic interference environment or a scene with strong metal shielding, the system can ensure accurate and reliable transmission of wireless unlocking signals and reduce signal loss and delay.

[0062] 4. Reduce mutual interference between energy and signal transmission:

[0063] In existing wireless transmission systems, since energy transmission and signal transmission are performed through two independent modules, mutual interference may occur, affecting the overall performance of the system. The fourth objective of the present invention is to optimize the energy and signal transmission paths through integrated design to reduce the interference between the two. Through reasonable frequency allocation, transmission protocol design and physical isolation means, it is ensured that energy transmission and signal transmission can be carried out efficiently and independently, thereby improving the stability and reliability of the system.

[0064] 5. Improve system durability and adaptability:

[0065] The present invention also aims to improve the durability of the entire system by reducing physical contact points. Traditional contact-based energy and signal transmission methods often affect the life and performance of the equipment due to problems such as contact point wear and contamination caused by long-term use. The present invention avoids the wear problem of physical contact points through wireless transmission, significantly improving the service life of the equipment. In addition, the present invention also optimizes the adaptability of wireless transmission, enabling it to work stably in various complex environments (such as humid, dusty or metal environments), reducing maintenance frequency and costs.

[0066] 6. Improve user experience and enhance system convenience:

[0067] Existing wireless energy transmission and signal transmission technologies sometimes require users to use keys to interact with locks in specific locations or environments, which is not intuitive and convenient. Another goal of the present invention is to enable users to perform unlocking operations more naturally and conveniently by optimizing the wireless transmission range and sensing sensitivity. Users only need to bring the key or controller close to the passive lock, without precise docking, to complete the transmission of energy supply and unlocking instructions, significantly improving the user experience.

[0068] 7. Enhanced security:

[0069] In the field of commodity display and anti-theft, security is of vital importance. In the prior art, the security of signal transmission is often affected by the external environment, and there is a risk of being intercepted or cracked. The seventh objective of the present invention is to ensure the security of signal transmission by designing a more secure encryption communication protocol. By adopting dynamic encryption technology, two-way authentication and other means, the security of the unlocking signal during transmission is ensured, the anti-cracking ability of the system is improved, and the anti-theft effect is enhanced.

[0070] 8. Wide range of application scenarios:

[0071] Another important goal of the present invention is to provide a universal solution for various fields such as commodity display anti-theft, smart door locks, smart warehousing, etc. Whether it is an anti-theft system for high-end commodity display cabinets or an access control system for smart homes, the method of the present invention is applicable and has good scalability, compatibility and flexibility, and can meet the needs of different application scenarios.

[0072] 9. Development trend:

[0073] With the rapid development of the Internet of Things, smart homes, and smart security systems, the market demand for efficient, stable, and low-maintenance passive locks is growing. The future development trend is to integrate energy transmission with signal transmission to reduce system complexity while improving transmission efficiency and signal stability. In addition, how to ensure the stability and anti-interference ability of wireless transmission systems in complex environments is also an important technical challenge facing the industry.

[0074] The present invention is based on existing low-power wireless energy transmission technologies, such as electromagnetic induction or magnetic resonance, but has made innovative improvements to the energy transmission mode. In traditional wireless energy transmission, energy transfer is continuous and only used for power supply. By sending energy in the form of intermittent pulses, not only the power supply function is realized, but also the signal transmission is realized through the timing coding of the pulses. Through this pulse coding mechanism, energy transmission and signal transmission no longer require independent hardware modules, which simplifies the system design and improves the transmission efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1The overall structure diagram of the wireless lock system designed for this purpose;

[0076] Figure 2 Schematic diagram of the key-end wireless energy transmission module designed for this purpose;

[0077] Figure 3 This is a schematic diagram of the wireless energy receiving and decoding module of the passive lock in this design. DETAILED DESCRIPTION

[0078] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0079] See also Figure 1-3 As shown, a method for energy transmission and signal transmission of a passive wireless lock includes the following steps:

[0080] S1: Energy transmission at the key end; insert the key into the key hole, press the key button, start the energy transmission module, and monitor the current value output by the key power supply to the energy transmission module;

[0081] The current value when the key is pressed without being inserted into the keyhole is I N , the maximum current when the key is pressed when inserted into the keyhole is I max , in I max After delay t s , (t s The current value is I L .

[0082] If I max <1.5*I N , indicating that the key is not correctly inserted into the lock, and an alarm signal is issued through the key;

[0083] If I L >1.2*I N , indicating that the energy receiving module of the lock is overloaded, and an alarm signal is sent through the key;

[0084] If I max ≥1.5*I N And I L ≤1.2*I N , indicating that the lock's energy receiving module is working properly.

[0085] S2: Energy reception and decoding at the lock end; when the energy receiving module of the lock is normal, the continuous power supply of the energy sending module is changed to pulse power supply. The pulse is generated by the switch between the power supply and the energy sending module controlled by the signal encoding module (the switch is a MOS tube). The continuous cycle and change law of the high level and low level of the pulse represent the sent unlocking password, that is, the sent unlocking password is superimposed in the wireless energy transmission process;

[0086] A high level that lasts for more than 0.5s is used as the start and end signals. After the start and end signals, a low level that lasts for 0.1s is used, and then a high level of 0.1s to 0.4s is used as the information code, representing 0 to 3 respectively. Each information code is separated by a low level that lasts for 0.1s. Multiple information codes constitute an unlocking password in a quaternary format. After the unlocking password is completed, a low level that lasts for 0.1s is used, and then a high level that lasts for more than 0.5s is used as the start and end signals. The unlocking password is generated cyclically and sent in a superimposed manner through the wireless energy transmission process.

[0087] S3: Unlocking and feedback; when the energy receiving module of the lock is normal, the energy signal received by the energy receiving module is sent to the signal decoding module through the RC low-pass filter, and then charged to the energy storage capacitor through the diode.

[0088] S4: Improve the anti-interference ability during transmission; the signal decoding module records the duration of each high level to form an array [N1, N2, ..., N n ], unit is ms;

[0089] Judge the values ​​in the array one by one from the beginning. If N k (k=1,2,…,n) is greater than 450, then from N k+1 Start taking numbers, assuming that N k+1 Afterwards, N m (m=k+2,k+3,…,n) is the first number greater than 450, then the received unlock password is [N k+1 ,N k+2 ,…,N m-1 ].

[0090] Perform unlock calculation, assuming that the built-in unlock password of the lock is [X1,X2,…,X p ](Each number has a value of 0 to 3). If the length of the received unlock password is not equal to the length of the built-in unlock password, it is considered that the unlocking has failed. If the length of the received unlock password is equal to the length of the built-in unlock password, the passwords are compared:

[0091] [dX1,dX2,…,dX p ]=[X1,X2,X3,…,X p ]*100-[N k+1 ,N k+2 ,…,N m-1 ]+100

[0092] Calculate [dX1, dX2, dX3, …, dX p ] If the RMS is less than or equal to 10, it indicates that the unlocking is successful. If the RMS is greater than 10, it indicates that the unlocking fails.

[0093] After the unlock fails, m+1 Start to obtain data again, form a new received unlocking password, and perform unlocking calculation again.

[0094] If the unlocking fails for 3 to 5 times in a row (determined by the user), the lock will send out an alarm signal, and the unlocking ends. The signal decoding module will no longer decode. It will not be able to decode again until the key is removed, the lock is disconnected and recharged.

[0095] S5: Improve system security; under the premise of successful unlocking, the signal decoding module controls the switch between the energy storage capacitor and the load (the switch is a MOS tube) to turn on, the load is energized, the unlocking mechanism is activated, the lock is opened, and the lock sends a successful unlocking signal.

[0096] S6: After step S2, monitor the current value output by the key power supply to the energy transmission module. When the maximum current value I max2 ≥I max , it indicates that the unlocking is successful, and the key records the unlocking success information; otherwise, it indicates that the unlocking fails, and the key records the unlocking failure information.

[0097] In this embodiment, in S1, the key end sends energy. The key end sends intermittent pulse energy through the wireless transmission module according to the set time coding rules. Each pulse has a different duration and represents different binary information. A long pulse of 0.1s represents "1" and a short pulse of 0.05s represents "0". At the start and end of the transmission, the key end sends a long pulse with a duration of more than 0.5s, indicating the start and end of the signal transmission.

[0098] In this embodiment, in S2, after the wireless receiving module at the lock end receives the pulse energy, it first enters the synchronization state and identifies the starting pulse of the transmission. The lock monitors the duration of each pulse in real time through the internal decoding circuit and decodes it into a corresponding binary signal. After the decoding is completed, the control circuit inside the lock verifies the signal to ensure the integrity and accuracy of the signal.

[0099] In this embodiment, in S3, after verification, if the received signal matches the preset unlocking password, the lock performs an unlocking operation, and the lock sends a feedback signal to the key end through the wireless module, indicating whether the unlocking is successful or failed.

[0100] In this embodiment, in S3, energy transmission and signal transmission are integrated into one wireless transmission path;

[0101] Specifically, 1. Design of the energy and signal transmission module on the key end

[0102] The core of the key end design is to generate pulsed wireless energy that can both transmit energy and carry signals by controlling the working state of the DC power supply. The specific structure is as follows:

[0103] DC Power Supply:

[0104] The DC power supply at the key end provides stable high-level energy as the basic power supply for the system.

[0105] Signal encoding module:

[0106] The signal encoding module generates a low-frequency pulse signal by controlling the on and off of the DC power supply, and realizes signal encoding at the same time. The specific implementation is as follows:

[0107] The signal encoding module converts the password into a binary signal sequence (eg "1010") according to the set unlocking password.

[0108] By controlling the length of time the DC power supply is turned on, the signal is encoded into a low-frequency pulse:

[0109] A long on-time (0.1s) represents a binary "1".

[0110] A short on-time (0.05s) represents a binary "0".

[0111] At the beginning and end of signal transmission, a long pulse lasting more than 0.5s is sent to mark the start and end of communication.

[0112] Energy sending module:

[0113] The low-frequency pulse signal generated by the signal encoding module directly controls the working state of the energy sending module. The implementation details of the energy sending module are as follows:

[0114] (1) When the DC power supply is in the on state, the energy transmission module converts the high-level DC energy into high-frequency alternating pulse energy and sends it out via wireless transmission.

[0115] (2) The frequency range of the high-frequency pulse is set according to the frequency band requirements of wireless transmission (such as 13.56 MHz or other suitable frequencies) to ensure the efficiency and stability of energy transmission.

[0116] Through this design, the key end embeds the signal into the low-frequency pulse of energy while sending energy, thereby realizing the integrated transmission of energy and signal.

[0117] 2. Design of energy and signal receiving module of passive lock end

[0118] The core of the passive lock is to extract the DC energy and the embedded low-frequency signal from the received high-frequency pulse energy. The specific structure is as follows:

[0119] Energy receiving module:

[0120] The passive lock end receives the high-frequency pulse wireless energy sent by the key end through the energy receiving module and divides it into two parts for processing.

[0121] Energy extraction part:

[0122] The high-frequency pulses are rectified and smoothed by a filter capacitor (such as an energy storage capacitor) and converted into a stable DC power supply for powering the load of the passive lock.

[0123] The design capacity of the filter capacitor can meet the instantaneous power demand of the passive lock load and ensure the stability of the power supply.

[0124] Signal extraction part:

[0125] The received high-frequency pulse signal is processed by an RC low-pass filter (composed of a resistor and a capacitor) to filter out the low-frequency pulse signal.

[0126] The design parameters of the RC low-pass filter (such as resistance and capacitance values) are set according to the frequency of the low-frequency pulse signal sent by the key end to ensure that the low-frequency pulse signal consistent with the key end signal encoding module is accurately extracted.

[0127] Signal decoding module:

[0128] The signal decoding module decodes the low-frequency pulse signal output from the RC low-pass filter and recovers the binary signal sequence sent by the key end. The specific implementation is as follows:

[0129] (1) The decoding module measures the duration of each low-frequency pulse:

[0130] (1) A pulse with a duration of 0.1 s is decoded as a binary "1".

[0131] (2) A pulse with a duration of 0.05 s is decoded as a binary “0”.

[0132] (2) The decoding module uses the start and end marks of the unlock signal (long pulses exceeding 0.5 s) as the boundaries of the data frame to ensure the integrity of the signal.

[0133] (3) By comparing the decoded signal sequence with the preset unlocking password, it is determined whether the unlocking signal is correct.

[0134] 3. Timing design of integrated energy and signal transmission

[0135] The key to the integrated design of energy and signal transmission lies in the reasonable arrangement of timing to ensure the integrity of signal transmission and the continuity of energy supply. The following are the specific details of timing design:

[0136] Pulse timing rules:

[0137] The pulse signal sent by the key terminal follows the following rules:

[0138] Each pulse consists of two phases: an on phase (high frequency energy is transmitted) and an off phase (no energy is transmitted).

[0139] The on-time of the pulse represents binary data according to the signal encoding rules (for example, a long pulse represents "1" and a short pulse represents "0").

[0140] The time interval of the disconnection phase is set to a fixed value (eg, 0.02s) to distinguish different pulse signals.

[0141] Synchronicity of signal and energy:

[0142] (1) During the conduction phase, the high-frequency pulse not only powers the passive lock, but also transmits signal encoding information.

[0143] (2) The off phase of the pulse will not affect the energy supply because the filter capacitor can continue to provide power to the load of the passive lock during the off phase.

[0144] Signal Transmission Integrity:

[0145] (1) By adding identification long pulses (more than 0.5s) at the beginning and end of the pulse sequence, the integrity of the signal transmission frame is ensured.

[0146] (2) The passive lock terminal enters the signal decoding state by detecting the identification pulse and exits the decoding state after receiving the complete frame.

[0147] 4. Parameter design of key modules

[0148] RC Low Pass Filter Design:

[0149] According to the frequency of the low-frequency pulse signal (eg, 10 Hz), the cutoff frequency of the RC filter is designed to be 1.5 to 2 times the frequency (eg, 15 Hz-20 Hz) to ensure the accuracy of filtering out the low-frequency signal.

[0150] Typical values ​​of the filter resistor and capacitor can be selected as: resistor 10kΩ, capacitor 10μF (specific values ​​can be adjusted according to the actual frequency).

[0151] Filter capacitor design:

[0152] (1) The filter capacitor is used to rectify the high-frequency pulse into a DC power supply. Its capacity must meet the instantaneous power demand of the passive lock load.

[0153] The typical capacity range is 10μF to 100μF, and the specific value is calculated based on the actual power consumption of the lock.

[0154] In this embodiment, frequency band optimization: using low-power, high-frequency wireless transmission bands, selecting appropriate wireless bands, and reducing electromagnetic interference in daily environments;

[0155] Specifically, 1. Select a suitable wireless transmission frequency band

[0156] The selection of wireless transmission frequency band is based on the following core factors: power limit, transmission efficiency, anti-interference ability and the use specifications of existing frequency bands. The frequency band optimization designed by the present invention is mainly reflected in the following aspects:

[0157] Use high frequency transmission band:

[0158] The present invention preferably uses a high frequency range (such as 13.56 MHz, 915 MHz, 2.4 GHz, etc.) because high frequency signals have the following advantages:

[0159] Higher transmission efficiency: Due to their shorter wavelength, high-frequency signals have higher energy transmission efficiency in electromagnetic induction or magnetic resonance wireless transmission.

[0160] Small antenna size: The antenna size required for high-frequency signals is smaller, which is conducive to the miniaturization design of system hardware.

[0161] Strong anti-interference ability: High-frequency signals have less interference with other low-frequency devices within a certain range, and are also more likely to avoid public interference signals in low-frequency bands.

[0162] Avoid crowded frequency bands:

[0163] (1) The wireless transmission frequency band needs to avoid the widely used crowded frequency bands (such as some public low-frequency bands) to reduce signal interference.

[0164] (2) For example, the 13.56 MHz frequency band (ISM band that complies with international standards) is used. This frequency band is suitable for short-distance, low-power wireless transmission and is widely used in technologies such as RFID and NFC. It is relatively clean and has less interference.

[0165] ISM frequency bands that comply with international standards:

[0166] The low-power transmission frequency band used in the present invention preferably selects the ISM (Industrial, Scientific and Medical) frequency band that complies with international standards, for example:

[0167] (1) 13.56 MHz (low frequency, suitable for short-distance transmission, high transmission stability).

[0168] (2) 915MHz (low-frequency UHF, suitable for medium-distance transmission, with strong signal penetration).

[0169] (3) 2.4 GHz (high frequency, suitable for short-distance high-speed transmission, but susceptible to interference from metal environments).

[0170] These frequency bands are protected by international radio regulations, do not require special frequency band authorization, and are suitable for low-power wireless transmission applications.

[0171] 2. Specific implementation of high-frequency transmission

[0172] The optimized design of the high-frequency transmission band involves the hardware and signal processing modules of the transmitter (key) and the receiver (passive lock), which are specifically implemented as follows:

[0173] Key-end high-frequency energy transmission module:

[0174] High frequency signal generation:

[0175] The key end uses an oscillation circuit (such as a crystal oscillator) to generate a high-frequency signal of the target frequency. For example, a 13.56MHz signal can be generated and amplified by a quartz crystal oscillator.

[0176] Carrier modulation:

[0177] Based on the high-frequency signal, the pulse coding technology is used to modulate the carrier to form a high-frequency transmission signal containing a low-frequency pulse signal. The modulation method can be:

[0178] ASK (Amplitude Shift Keying): Carries signal information by changing the amplitude of high-frequency signals, and is suitable for power-sensitive scenarios.

[0179] FSK (Frequency Shift Keying): Transmits signal information by changing the frequency of high-frequency signals, and has stronger anti-interference ability.

[0180] Low power design:

[0181] The power control module limits the transmission power to an appropriate range (such as less than 100mW) to ensure compliance with low-power wireless transmission specifications and avoid interference with other frequency band devices.

[0182] 3. Passive lock end high frequency energy receiving module:

[0183] (1) High frequency receiving antenna design:

[0184] The passive lock end is equipped with a high-frequency receiving antenna whose size and design parameters match the selected frequency band. For example, the antenna for the 13.56MHz band usually adopts a helical structure or a flat coil, which is small in size and suitable for embedded applications.

[0185] (2) High frequency signal demodulation:

[0186] The received high-frequency signal is used to extract the contained low-frequency pulse signal through a demodulation circuit (such as a diode detector or a mixer). The demodulation process includes:

[0187] (1) Detect the amplitude or frequency changes of the carrier signal and extract the signal information conveyed therein.

[0188] (2) Restore the pulse coded signal and provide input data for the subsequent decoding module.

[0189] (3) Energy extraction and rectification:

[0190] The high frequency energy is converted into DC energy through a rectifier circuit (such as a diode bridge rectifier) ​​to power the load of the passive lock.

[0191] 4. Frequency band optimization anti-interference strategy

[0192] The design of frequency band optimization not only requires the selection of appropriate frequency bands, but also requires measures to enhance the anti-interference ability of transmission, as follows:

[0193] First, dynamic frequency adjustment:

[0194] If there is an interference source (such as other wireless devices) in the target frequency band, the key end can dynamically switch to an adjacent backup frequency band through the frequency adjustment module. For example, when the 13.56MHz frequency band is interfered, it can switch to a higher frequency (such as 14MHz).

[0195] The dynamic frequency adjustment algorithm is based on real-time monitoring of signal strength and interference level, and ensures transmission stability by selecting the frequency band with the least interference.

[0196] Second, narrowband transmission:

[0197] (1) The transmission frequency band of the key end and the passive lock end is designed to be narrow-band transmission (such as a width of ±10kHz) to reduce the impact of interference within the frequency band.

[0198] (2) The design of narrowband signals improves the signal's anti-interference ability by concentrated power transmission.

[0199] Third, shielding interference design:

[0200] (1) The key electronic components (such as the transmitting module and the receiving module) at the key end and the passive lock end adopt a shielded shell design to reduce the impact of external electromagnetic interference on signal transmission.

[0201] 5. Hardware design details for high-frequency transmission band optimization

[0202] First, the hardware design of the transmitter (key):

[0203] Oscillator: A quartz crystal oscillator is used to generate a stable high-frequency signal (such as 13.56MHz).

[0204] Modulation circuit: Use ASK modulator to superimpose low-frequency pulse signal on high-frequency carrier.

[0205] Power amplifier circuit: The transmit signal strength is increased through the power amplifier, and the power range is strictly controlled within the low power (such as 1-100mW) specification.

[0206] Matching network: Improve the energy transmission efficiency of the antenna through impedance matching circuit.

[0207] Second, the hardware design of the receiving end (passive lock):

[0208] (1) Receiving antenna: A high-frequency antenna designed to match the target frequency band (such as a helical antenna).

[0209] (2) Demodulation circuit: Use a diode detector or mixer to extract the pulse signal from the carrier.

[0210] (3) Rectification circuit: The high-frequency pulse signal is converted into DC power through a bridge rectifier.

[0211] In this embodiment, dynamic frequency adjustment: during signal transmission, the system can dynamically adjust the transmission frequency according to environmental conditions to avoid interference frequency segments and ensure the stability of signal transmission;

[0212] Specifically, 1. The core principle of dynamic frequency adjustment

[0213] Dynamic frequency adjustment is based on the principle of frequency hopping (FH) technology. It avoids interference by switching the transmission frequency between multiple available frequency bands. The core workflow of this technology is as follows:

[0214] Frequency band division:

[0215] A plurality of available frequency bands are pre-divided within the wireless transmission range, for example, a plurality of sub-frequency bands such as 13.50 MHz, 13.55 MHz, and 13.60 MHz are divided near the 13.56 MHz frequency band.

[0216] The bandwidth of each sub-band is usually between 10kHz and 50kHz to cover an appropriate transmission range.

[0217] Real-time interference detection:

[0218] (1) The system determines whether the current frequency band is interfered by monitoring the interference strength of the current transmission frequency band (such as signal-to-noise ratio SNR or signal strength RSS1).

[0219] (2) If the signal quality of the current frequency band is detected to be lower than the set threshold, the system will trigger the frequency switching mechanism.

[0220] Frequency Hopping:

[0221] (1) The system selects a new frequency band with lower interference from a predefined frequency band list for transmission.

[0222] (2) The hopping mechanism can be random or based on a preset frequency hopping sequence or algorithm (such as a pseudo-random sequence).

[0223] Frequency Synchronization:

[0224] (1) To ensure that the transmitter (key) and receiver (passive lock) can still communicate normally after switching frequencies, the system uses a synchronization signal or protocol to keep the frequencies of the transmitter and receiver consistent.

[0225] 2. Implementation of dynamic frequency adjustment at the key end

[0226] Frequency generation module:

[0227] The key end is equipped with a frequency synthesizer (such as a phase-locked loop PLL or a direct digital frequency synthesizer DDS) to dynamically generate different transmission frequencies.

[0228] The frequency synthesizer can quickly switch the output frequency according to the control signal, for example, from 13.56MHz to 13.50MHz or 13.60MHz.

[0229] Interference detection module:

[0230] (1) The key end monitors the transmission quality of the current frequency band through a signal feedback mechanism, including the following parameters:

[0231] Signal strength (RSS1): Determine the signal quality of the current frequency band by detecting the return signal strength of the receiving end.

[0232] Bit Error Rate (BER): Determines the signal transmission accuracy of the current frequency band through decoding comparison.

[0233] (2) If the signal strength of the current frequency band is found to decrease or the bit error rate increases, the system will trigger a frequency switch.

[0234] Frequency switching logic:

[0235] (1) The key end selects an available frequency band from a pre-defined frequency band list based on the interference detection result.

[0236] (2) After switching the frequency band, the key end notifies the passive lock end through a synchronization signal to adjust the frequency to ensure that both sides remain consistent.

[0237] 3. Implementation of dynamic frequency adjustment of passive lock end

[0238] Frequency receiving module:

[0239] The passive lock end is equipped with a broadband receiving module that can cover all available frequency bands (such as 13.50MHz~13.60MHz).

[0240] The broadband receiving module adjusts the receiving frequency in real time through the frequency tracking mechanism to match the frequency switching on the key end.

[0241] Frequency Tracking and Synchronization:

[0242] (1) The passive lock end determines the current transmission frequency by detecting the synchronization signal sent by the key end.

[0243] (2) If a frequency change is detected, the passive lock end will adjust the receiving frequency through the internal frequency synthesis module to keep it consistent with the key end.

[0244] Signal processing and decoding:

[0245] (1) After adjusting the receiving frequency, the passive lock end demodulates and decodes the high-frequency signal to extract the transmitted low-frequency pulse signal.

[0246] 4. Implementation process of dynamic frequency adjustment

[0247] The following is the specific implementation process of dynamic frequency adjustment:

[0248] Initialization frequency band: The transmitter (key) and the receiver (passive lock) select the default center frequency band (such as 13.56MHz) for communication at startup.

[0249] Real-time monitoring: The key end and the passive lock end monitor the signal quality of the current frequency band in real time to determine whether there is interference (such as reduced signal-to-noise ratio, increased bit error rate, etc.).

[0250] Trigger frequency hopping: If interference is detected, the key end triggers frequency switching and selects a new frequency band for transmission (for example, switching from 13.56MHz to 13.60MHz). The key end transmits the new frequency information to the passive lock end through a synchronization signal.

[0251] Frequency synchronization: After receiving the synchronization signal, the passive lock adjusts the receiving frequency to match the frequency of the key. Both parties continue to communicate in the new frequency band.

[0252] Cyclic optimization: The system continuously monitors the frequency band quality during the entire transmission process. If the new frequency band is interfered again, the above steps are repeated.

[0253] Redundancy design: During signal transmission, redundant codes and check codes are added to ensure accurate signal decoding and transmission reliability;

[0254] Specifically, redundancy design implements the error detection and correction functions by adding redundant information (such as redundant code and check code) to the original signal. Its core ideas include the following two parts:

[0255] 1. Add redundant code:

[0256] Redundancy code is the addition of extra information to the original signal (i.e. the binary sequence that unlocks the code) to detect and correct errors during transmission.

[0257] For example, the signal's fault tolerance can be improved by repeatedly transmitting part of the signal or adding check information (such as parity bits).

[0258] 1. Add verification code:

[0259] (1) The check code is additional information generated by performing specific mathematical operations on the original signal and is used to detect whether an error occurs during the transmission process.

[0260] (2) Check codes can be used for simple error detection (such as parity check) or complex error correction (such as cyclic redundancy check CRC).

[0261] 2. Redundancy code and check code generation on the key side

[0262] On the key side, the generation of redundant code and check code is one of the core functions of the signal encoding module, which is implemented as follows:

[0263] 1.Signal coding and redundancy design:

[0264] The key end generates an original binary signal sequence according to the set unlocking password, for example, the unlocking password is "1010".

[0265] On this basis, redundant information is added, for example:

[0266] Repetition code: Each bit of information is transmitted repeatedly, for example, "1010" becomes "11001100", and each bit is repeated twice to improve transmission reliability.

[0267] Parity check: A parity bit is added to the end of each group of data to detect whether a single-bit error occurs during transmission.

[0268] The redundant signal sequence is transmitted via low-frequency pulse encoding, for example:

[0269] Encoded redundant signal: If "1010" is added with a 1-bit check code to become "10101", the corresponding pulse signal sequence is generated by the pulse encoding module.

[0270] 2. Verification code generation method:

[0271] The key end generates the verification code by the following method:

[0272] (1) Parity check: Count the number of "1"s in each set of data:

[0273] (1) If the number of "1" is odd, the check digit is "1";

[0274] (2) If the number of "1" is even, the check digit is "0".

[0275] (2) Cyclic Redundancy Check (CRC):

[0276] (1) The key performs a binary operation (such as modulo 2 division) on the original signal using a specific generating polynomial to generate a check code of a fixed length (such as 8 bits or 16 bits).

[0277] (2) The check code is appended to the original signal to form a complete transmission data frame.

[0278] 3. Data frame design:

[0279] To ensure the integrity of the signal, the key end embeds the redundant code and the check code into the complete data frame. Each frame includes:

[0280] (1) Start flag: used to mark the beginning of a data frame (for example, a long pulse signal indicates the start).

[0281] (2) Data domain: contains the original signal and redundant codes (such as repetition codes, parity bits or CRC codes).

[0282] (3) End flag: used to mark the end of a data frame (for example, a long pulse signal indicates the end).

[0283] (4) For example, after adding the parity check code to the original signal "1010", the data frame may be:

[0284] Start mark | 10101 (data and checksum) | end mark.

[0285] 4. Analysis of Redundancy Code and Check Code of Passive Lock Terminal

[0286] The passive lock terminal analyzes and verifies the received pulse signal through the signal decoding module. The specific process is as follows:

[0287] 1. Data decoding:

[0288] The passive lock terminal extracts the low-frequency pulse signal through an RC low-pass filter and decodes the pulse signal into a binary signal sequence.

[0289] The decoded signal may contain errors, such as "10101" being decoded as "10100".

[0290] 2. Error detection and correction:

[0291] The passive lock detects whether an error occurs during transmission by analyzing the redundant code and check code, and attempts to correct the error. The specific methods include:

[0292] (1) Parity check:

[0293] Count the number of "1"s based on the received signal and compare it with the check digit.

[0294] If the comparison result is inconsistent, it means that a single-bit error has occurred in the data.

[0295] (2) Repeat code error correction:

[0296] If a repetition code mechanism is used (such as repeating each bit twice), the passive lock terminal judges the repeated data and selects the value with the largest number of occurrences as the valid value. For example, "11001100" is decoded as "1010".

[0297] (3) CRC check:

[0298] The passive lock end calculates the received complete data frame (including the check code) according to the same generating polynomial.

[0299] If the calculation result is 0, it means that there is no error in the data frame; otherwise, it means that there is an error in the data frame.

[0300] 5.Signal verification and correction:

[0301] If the verification result indicates that the signal is erroneous and cannot be corrected, the lock end will request the key end to retransmit the signal (triggered by resending the start flag) to ensure that the signal is received completely.

[0302] In this embodiment, dynamic encryption is used: the unlocking signal uses a dynamic encryption algorithm during each transmission process to ensure the uniqueness and timeliness of the signal and prevent signal replay attacks;

[0303] Specifically, the key end is responsible for generating a dynamically encrypted unlocking signal, which is implemented as follows:

[0304] 6. Generation and storage of encryption keys:

[0305] The key end and the passive lock end share a symmetric encryption key (such as a 128-bit or 256-bit key) in advance.

[0306] The key can be set at the factory or changed dynamically through a key update mechanism.

[0307] The key is stored using hardware encryption storage (such as a security chip) or software encryption storage to prevent key leakage.

[0308] 7. Generation of dynamic parameters:

[0309] The key end generates dynamic parameters (i.e. encryption factors) before each signal transmission. Common dynamic parameters include:

[0310] (1) Timestamp: A time stamp (such as seconds or milliseconds) generated based on the current system time to ensure the timeliness of the signal.

[0311] (2) Random numbers: Unpredictable random values ​​are generated by a random number generator.

[0312] (3) Counter: The count value increases with each transmission to ensure the uniqueness of the signal and prevent duplication.

[0313] 8. Application of encryption algorithm:

[0314] The key end uses dynamic parameters and unlock passwords to encrypt the signal and generate a dynamic unlock signal. The encryption algorithm can use the following common symmetric encryption algorithms:

[0315] (1) AES (Advanced Encryption Standard): An efficient and secure symmetric encryption algorithm that supports 128-bit, 192-bit, and 256-bit key lengths.

[0316] (2) DES / 3DES (Data Encryption Standard): An earlier symmetric encryption algorithm, but its security is not as good as AES and is mainly used in scenarios with low security requirements.

[0317] (3) ChaCha20: A lightweight encryption algorithm suitable for low-power devices.

[0318] (2) The encryption process is as follows:

[0319] (1) Encrypted data = Encrypt(key, unlock password + dynamic parameters)

[0320] (2) Where Encrypt represents an encryption algorithm, the unlock password is a preset unlock code, and the dynamic parameter is a timestamp, a random number, or a counter.

[0321] 9. Transmission of encrypted signals:

[0322] (1) The key end converts the encrypted signal into a wireless pulse signal through a pulse encoding module and sends it to the passive lock end.

[0323] (2) Data frame structure:

[0324] Start mark: marks the beginning of the signal.

[0325] Encrypted signal: contains the unlocking signal after dynamic encryption.

[0326] Checksum: used to detect transmission errors.

[0327] End mark: marks the end of the signal.

[0328] 10. Decryption and verification of dynamic encryption signals at the passive lock end

[0329] The passive lock end is responsible for receiving the dynamic encryption signal and performing decryption and verification. The specific implementation is as follows:

[0330] First. Synchronization of dynamic parameters:

[0331] The passive lock end needs to synchronize dynamic parameters with the key end to correctly decrypt the received signal. The synchronization methods include:

[0332] Timestamp synchronization: The passive lock end keeps time synchronization with the key end based on its own time (usually the error does not exceed a few seconds).

[0333] Counter synchronization: The passive lock side maintains a counter that is consistent with the counter on the key side.

[0334] Random number transmission: If the dynamic parameter uses a random number, the key end is required to send the random number as part of the signal to the passive lock end.

[0335] Second. Signal decryption:

[0336] (1) The passive lock uses the preset symmetric key and synchronized dynamic parameters to decrypt the received encrypted signal and restore the original unlocking password.

[0337] (2) Decryption formula:

[0338] (1) Unlock password = Decrypt (key, received encrypted signal)

[0339] (2) Wherein, Decrypt represents the decryption algorithm, which corresponds to the encryption algorithm on the key side.

[0340] Third. Unlock password verification:

[0341] (1) The passive lock terminal compares the decrypted unlocking password with the preset password:

[0342] (1) If the password matches and the dynamic parameters are valid, the unlock operation is performed.

[0343] (2) If the password does not match or the dynamic parameter is invalid, unlocking is rejected.

[0344] Fourth. Anti-replay mechanism:

[0345] (1) The passive lock will record dynamic parameters to prevent repeated use. For example:

[0346] (1) Timestamp verification: If the timestamp is earlier than the current time or exceeds the allowed time range, the signal is deemed invalid.

[0347] (2) Counter verification: If the count value is less than or equal to the previously received count value, the signal is deemed invalid.

[0348] Random number verification: If the random number is already in the history, the signal is considered invalid.

[0349] In this embodiment, two-way authentication is adopted: the key end and the lock end perform two-way authentication before signal transmission to ensure that energy and signal transmission can only be carried out after the identity authentication of both parties is passed.

[0350] Specifically, the two-way authentication process on the key side

[0351] In two-way authentication, the key end needs to prove its identity and verify the identity of the lock end. The specific implementation is as follows:

[0352] 1. Key storage:

[0353] The key side stores a preset key (symmetric key) or a private key (asymmetric key) shared with the lock side.

[0354] The keys are stored in a secure chip or hardware security module (HSM) to prevent key leakage.

[0355] 2. Generate challenge value:

[0356] (1) At the beginning of authentication, the key side generates a random number as a challenge value (Challenge).

[0357] (2) The challenge value is combined with the key through an encryption algorithm to generate authentication data and sent to the lock end.

[0358] 3. Verify the lock's identity:

[0359] (1) After receiving the response from the lock, the key end uses the shared key or the corresponding public key to decrypt and verify the response.

[0360] (2) If the decrypted data matches the expected value on the key side, it means that the identity of the lock side is legitimate.

[0361] 4. Return authentication response:

[0362] (1) After verifying the identity of the lock, the key uses the challenge value sent by the lock to calculate and generate its own authentication response and return it to the lock.

[0363] (2) The response data is generated through an encryption algorithm combined with a shared key to ensure that it cannot be forged.

[0364] 5. Two-way authentication process on the lock side

[0365] After receiving the authentication request from the key end, the lock end needs to complete the following operations:

[0366] Key storage:

[0367] The lock side stores a preset key (symmetric key) or a public key (asymmetric key) shared with the key side.

[0368] The key is stored in the hardware encryption module to ensure the security of the key.

[0369] 6. Receive and decrypt the key challenge value:

[0370] (1) The lock receives the challenge value sent by the key and verifies the challenge value through an encryption algorithm combined with a shared key.

[0371] (2) After verification, it means that the key end is legal.

[0372] 7. Generate a response and return:

[0373] (1) The lock uses the challenge value sent by the key end and combines it with its own key to generate an authentication response and return it to the key end.

[0374] (2) The response data is generated through an encryption algorithm to ensure that it cannot be forged.

[0375] 8. Send challenge value:

[0376] The lock generates a new random challenge value and sends it to the key, requiring the key to provide an authentication response.

[0377] 9. Verify the key end response:

[0378] After the lock receives the response from the key, it decrypts and verifies the response data using an encryption algorithm combined with a shared key.

[0379] If the verification is successful, it means that the key end identity is legal.

[0380] In this embodiment, Figure 1The power supply is a DC power supply with a high-level output. The signal encoding module controls the on-off between the power supply and the energy transmission module. The on-off presents a low-frequency pulse signal, and the length of the on-time represents the signal encoding. The energy transmission module converts the high-level power supply energy in the on-phase into a high-low alternating high-frequency pulse energy and sends it out. The energy receiving module receives the high-frequency pulse energy. On the one hand, the high-frequency pulse passes through the RC low-pass filter to form the same low-frequency pulse signal as the signal encoding module, and on the other hand, it passes through the filter capacitor to form a high-level power supply to the load.

[0381] Key end structure:

[0382] (1) DC power supply:

[0383] The key end is equipped with a DC power supply, which outputs stable high-level power energy to provide basic power for the entire system.

[0384] (2) Signal encoding module:

[0385] The signal encoding module is responsible for controlling the on / off between the DC power supply and the energy transmission module. A low-frequency pulse signal is generated by turning the power supply on and off, where:

[0386] The length of the on-time represents the coded information of the signal (eg, 0.1s represents binary "1", and 0.05s represents binary "0").

[0387] The signal encoding module converts the unlocking signal into a series of low-frequency pulse signals according to a preset encoding rule.

[0388] (3) Energy sending module:

[0389] The energy sending module converts the high-level power energy corresponding to the low-frequency pulse signal generated by the signal encoding module into high-frequency pulse wireless energy that alternates between high and low.

[0390] When the DC power supply is turned on, the energy transmission module outputs a high-frequency pulse signal to complete the wireless transmission of energy.

[0391] Passive locking structure:

[0392] (1) Energy receiving module:

[0393] The passive lock receives the high-frequency pulse wireless energy sent by the key end through the energy receiving module. The received high-frequency energy undergoes the following two processes:

[0394] Low-frequency signal restoration: The high-frequency pulse signal passes through an RC low-pass filter to extract a low-frequency pulse signal that is consistent with the key-end signal encoding module.

[0395] Power extraction: The high-frequency pulse signal is processed by a filter capacitor to form a stable high-level DC power supply, which is used to power the passive lock load.

[0396] (2) Signal decoding module:

[0397] The signal decoding module decodes the low-frequency pulse signal generated by the RC low-pass filter into the original binary signal sequence (such as "1" and "0"), and compares it with the preset unlocking password. If the signal decoding is successful and the password matches, the unlocking operation is performed.

[0398] (3) Load module:

[0399] The load module of the passive lock includes a lock body control circuit and an actuator. The load module is powered by a DC power supply provided by the energy receiving module, and performs a specific unlocking action after the signal decoding module issues an unlocking instruction.

[0400] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to the present invention are within the scope of protection.

Claims

1. A method for energy transmission and signal transmission of a passive wireless lock, characterized in that: The following steps are involved: S1: Insert the key into the lock, press the key button, start the energy sending module, and monitor the current value output by the key power supply to the energy sending module; The current value when the key is pressed without being inserted into the keyhole is I N , the maximum current when the key is pressed when inserted into the keyhole is I max , in I max After delay t s , the current value is I L ; S2: When the energy receiving module of the lock is normal, the continuous power supply of the energy sending module is changed to pulse power supply. The pulse is generated by the switch between the power supply and the energy sending module controlled by the signal encoding module. The continuous cycle and change rule of the high level and low level of the pulse represent the sent unlocking password, that is, the sent unlocking password is superimposed in the wireless energy transmission process; A high level lasting more than 0.5s is used as the start and end signals. After the start and end signals, a low level lasting 0.1s is used, and then a high level of 0.1s to 0.4s is used as the information code, representing 0 to 3 respectively. Each information code is separated by a low level lasting 0.1s. Multiple information codes constitute the unlocking password in quaternary format. After the unlocking password is completed, a low level lasting 0.1s is used, and then a high level lasting more than 0.5s is used as the start and end signals. The unlocking password is generated cyclically and sent in a superimposed manner through the wireless energy transmission process; S3: When the energy receiving module of the lock is normal, the energy signal received by the energy receiving module is sent to the signal decoding module through the RC low-pass filter, and then charged to the energy storage capacitor through the diode; S4: The signal decoding module records the duration of each high level and forms an array [N1, N2, ..., N n ], unit is ms; Determine the values ​​in the array one by one from the beginning, N k (k=1,2,…,n) is greater than 450, then from N k+1 Start taking numbers at N k+1 Afterwards, N m (m=k+2,k+3,…,n) is the first number greater than 450, then the received unlock password is [N k+1 ,N k+2 ,…,N m-1 ]. Perform unlock calculation, assuming that the built-in unlock password of the lock is [X1,X2,…,X p ], if the length of the received unlock password is not equal to the length of the built-in unlock password, it is considered that the unlocking failed. If the length of the received unlock password is equal to the length of the built-in unlock password, the password comparison is performed: [dX1, dX2, …, dX p ]=[X1,X2,X3,…,X p ]*100-[N k+1 ,N k+2 ,…,N m-1 ]+100Calculate [dX1, dX2, dX3, …, dX p ], if the RMS is less than or equal to 10, it means the unlocking is successful, and if the RMS is greater than 10, it means the unlocking fails; If the unlock fails, m+1 Start to get data again, form a new received unlocking password, and perform unlocking calculation again; S5: On the premise of successful unlocking, the signal decoding module controls the switch between the energy storage capacitor and the load to turn on, the load is energized, the unlocking mechanism is activated, the lock is opened, and the lock sends a successful unlocking signal; S6: After step S2, monitor the current value output by the key power supply to the energy transmission module. When the maximum current value I max2 ≥I max , it indicates that the unlocking is successful, and the key records the unlocking success information; otherwise, it indicates that the unlocking fails, and the key records the unlocking failure information.

2. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S1, the key end sends energy. The key end sends intermittent pulse energy through a wireless transmission module according to a set time coding rule.

3. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S1, each pulse has a different duration, representing different binary information. A long pulse of 0.1s represents "1", and a short pulse of 0.05s represents "0". At the beginning and end of the transmission, the key end sends a long pulse with a duration of more than 0.5s, indicating the start and end of the signal transmission.

4. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S1: I max <1.5*I N , indicating that the key is not correctly inserted into the lock, and an alarm signal is issued through the key; I L >1.2*I N , indicating that the energy receiving module of the lock is overloaded, and an alarm signal is sent through the key; I max ≥1.5*I N And I L ≤1.2*I N , indicating that the lock's energy receiving module is working properly.

5. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S2, after receiving the pulse energy, the wireless receiving module at the lock end first enters the synchronization state and recognizes the starting pulse of the transmission.

6. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S2, the lock monitors the duration of each pulse in real time through an internal decoding circuit and decodes it into a corresponding binary signal.

7. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S2, after the decoding is completed, the control circuit inside the lock verifies the signal to ensure the integrity and accuracy of the signal.

8. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S3, energy transmission and signal transmission are integrated into one wireless transmission path.

9. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In the S4, a low-power, high-frequency wireless transmission band is used to reduce electromagnetic interference in daily environments; Dynamic frequency adjustment: During signal transmission, the system can dynamically adjust the transmission frequency according to environmental conditions to avoid interference frequency segments and ensure the stability of signal transmission; Redundant design: During signal transmission, redundant codes and check codes are added to ensure accurate signal decoding and transmission reliability.

10. The energy transmission and signal transmission method of a passive wireless lock according to claim 1, characterized in that: In S5, dynamic encryption is used: the unlocking signal uses a dynamic encryption algorithm during each transmission process to ensure the uniqueness and timeliness of the signal and prevent signal replay attacks; Two-way authentication is adopted: the key end and the lock end perform two-way authentication before signal transmission to ensure that energy and signal transmission can only be carried out after the identity authentication of both parties is passed.

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