阅读说明：本技术 一种基于蓝牙rssi的数字钥匙定位方法 (Bluetooth RSSI-based digital key positioning method ) 是由 张祥 曾建军 胡彬 于 2020-12-15 设计创作，主要内容包括：本发明公开了一种基于蓝牙RSSI的数字钥匙定位方法,该方法包括设置一个蓝牙钥匙控制器和三个蓝颜天线,通过手机APP和蓝牙钥匙控制器主模块完成蓝牙配对,利用手机APP发送广播包,蓝牙主模块通过LIN总线获取到三个蓝牙天线对手机的接收灵敏度RSSI、通过蓝牙射频底层读取到蓝牙射频接受灵敏度值RSSI,最后通过三角定位算法计算手机相对于车身的位置。本发明是创新产品汽车数字钥匙核心算法,具有速度快,成本低的特征,同时由于手机APP的蓝牙角色采用的是主机,手机APP在手机端比从机的方式兼容性更好。(The invention discloses a digital key positioning method based on Bluetooth RSSI, which comprises the steps of setting a Bluetooth key controller and three blue-color antennas, completing Bluetooth pairing through a main module of a mobile phone APP and the Bluetooth key controller, sending a broadcast packet by using the mobile phone APP, acquiring the receiving sensitivity RSSI of the three Bluetooth antennas to a mobile phone through an LIN bus by the Bluetooth main module, reading a Bluetooth radio frequency receiving sensitivity value RSSI through a Bluetooth radio frequency bottom layer, and finally calculating the position of the mobile phone relative to a car body through a triangular positioning algorithm. The invention is an innovative product of a core algorithm of an automobile digital key, has the characteristics of high speed and low cost, and simultaneously, because the Bluetooth role of the mobile phone APP is the host, the mobile phone APP has better compatibility at the mobile phone end than the slave machine.)

1. A Bluetooth positioning method based on RSSI is characterized by comprising the following steps:

s1: the digital key mobile phone APP finishes the Bluetooth pairing process of the mobile phone and the digital key main module through a Bluetooth binding process and a Bluetooth broadcast channel of the Bluetooth, only the Bluetooth equipment passing the security authentication is successfully paired, and once the security authentication fails, the Bluetooth pairing is quitted;

s2: after the Bluetooth pairing is completed, the digital key mobile phone APP sends the physical characteristic information of the mobile phone to the digital key main module through a specific GATT data stream;

s3: the digital key main module informs the received physical characteristic information of the mobile phone to 3 Bluetooth antennas through an LIN bus in an LIN diagnosis mode; the transmission of the transmission layer conforms to an ISO15765-2 multi-frame transmission principle, and the protocol layer conforms to an ISO14229 service standard;

s4: the Bluetooth antenna receives the physical characteristic information of the mobile phone and then temporarily stores the physical characteristic information into the RAM, so that the Bluetooth antenna identifies whether the mobile phone is a broadcast message sent by the mobile phone connected with the Bluetooth antenna or not through the received mobile phone characteristic information;

s5: the method comprises the steps that a digital key mobile phone APP sends a broadcast packet, and mobile phone physical characteristic information is attached to the broadcast packet;

s6: the Bluetooth antenna scans all Bluetooth broadcast packets in a Bluetooth broadcast channel; only the broadcast packet conforming to the mobile phone feature information received in S4 is processed; meanwhile, a radio frequency receiving sensitivity RSSI value sensed when the broadcast packet is received is obtained through a Bluetooth radio frequency bottom layer;

s7: the digital key Bluetooth main module receives a data packet sent by the mobile phone APP through the paired private channel, and can acquire a radio frequency receiving sensitivity RSSI value at the moment through a Bluetooth radio frequency bottom layer;

s8: the digital key Bluetooth master module acquires the RSSI acquired by the Bluetooth antenna in S6 through an LIN bus and periodically polls the RSSIs of 3 Bluetooth antennas in a LIN scheduling table mode;

s9: the digital key Bluetooth main module calculates the position of the current mobile phone relative to the vehicle body through a triangulation algorithm by using the 4 RSSI values obtained in S8, and judges whether the mobile phone is in the vehicle, namely a left PE, a right PE, a rear PE and a welcome area.

2. The digital key location algorithm for vehicles based on bluetooth RSSI of claim 1, wherein the operating current of the bluetooth main module and 3 bluetooth antennas is less than 100mA, and the quiescent current is less than 1.5 mA.

3. The bluetooth RSSI-based automobile digital key location algorithm according to claim 1, wherein before the steps are performed, bluetooth transmission and antenna efficiency tests are required to be completed by the bluetooth rf of the bluetooth main module and the 3 bluetooth antennas, so as to ensure that the actual bluetooth receiving sensitivity is consistent in performance.

4. The automobile digital key positioning algorithm based on Bluetooth RSSI of claim 1, wherein the 3 Bluetooth antennas are required to be arranged at the left front part, the right front part and the tail part of the automobile body, and are symmetrically arranged at the left and right positions, and the Bluetooth main module and the Bluetooth tail antenna are arranged on the central axis of the automobile body.

5. The automobile digital key positioning algorithm based on Bluetooth RSSI of claim 1, wherein Bluetooth radio frequency differences of compatible mobile phone brands are required, and Bluetooth performances and parameters of mainstream mobile phone brands are required to be calibrated.

Technical Field

The invention relates to the field of automobile digital keys, in particular to a digital key positioning method based on Bluetooth RSSI.

Background

The current automobile key experiences the development of mechanical key, RKE remote control key and PEPS intelligent key in the third generation through technical iteration, and the intelligent mobile phone becomes a necessary product for people to carry in daily life due to the popularization of the intelligent mobile phone and the deep mind of mobile payment concept, and meanwhile, due to the rise of sharing economy, the digital key based on the intelligent mobile phone draws extensive attention of the market. The digital key based on the smart phone covers the traditional automobile key, and meanwhile, new functional characteristics such as key sharing, interface display, digital safety and the like are added. The PEPS intelligent key has the advantages that the function of the existing PEPS intelligent key is completely replaced, the function of positioning the mobile phone is required to be completed, whether the mobile phone is in the car or out of the car is identified, and the PEPS controller is matched to complete the functions of passively entering the PE and passively starting the PS. For example, when the bluetooth digital key is determined to be located in the vehicle, the user is allowed to start the engine. When the Bluetooth digital key is judged to be positioned outside the automobile, only the user is allowed to open or close the automobile door, and the user is forbidden to start the engine. The digital key location capability is therefore critical.

The existing digital key positioning algorithm has long calculation time, slow response and higher required equipment cost, thus leading to poor user experience and difficult popularization and application.

Disclosure of Invention

In view of the above, the present invention provides a digital key positioning method with fast response and low hardware cost.

The purpose of the invention is realized by the following technical scheme:

a Bluetooth positioning method based on RSSI specifically comprises the following steps:

s1: the digital key mobile phone APP finishes the Bluetooth pairing process of the mobile phone and the digital key main module through a Bluetooth binding process and a Bluetooth broadcast channel of the Bluetooth, only the Bluetooth equipment passing the security authentication is successfully paired, and once the security authentication fails, the Bluetooth pairing is quitted;

s2: after the Bluetooth pairing is completed, the digital key mobile phone APP sends the physical characteristic information of the mobile phone to the digital key main module through a specific GATT data stream;

s3: the digital key main module informs the received physical characteristic information of the mobile phone to 3 Bluetooth antennas through an LIN bus in an LIN diagnosis mode; the transmission of the transmission layer conforms to an ISO15765-2 multi-frame transmission principle, and the protocol layer conforms to an ISO14229 service standard;

s4: the Bluetooth antenna receives the physical characteristic information of the mobile phone and then temporarily stores the physical characteristic information into the RAM, so that the Bluetooth antenna identifies whether the mobile phone is a broadcast message sent by the mobile phone connected with the Bluetooth antenna or not through the received mobile phone characteristic information;

s5: the method comprises the steps that a digital key mobile phone APP sends a broadcast packet, and mobile phone physical characteristic information is attached to the broadcast packet;

s6: the Bluetooth antenna scans all Bluetooth broadcast packets in a Bluetooth broadcast channel; only the broadcast packet conforming to the mobile phone feature information received in S4 is processed; meanwhile, a radio frequency receiving sensitivity RSSI value sensed when the broadcast packet is received is obtained through a Bluetooth radio frequency bottom layer;

s7: the digital key Bluetooth main module receives a data packet sent by the mobile phone APP through the paired private channel, and can acquire a radio frequency receiving sensitivity RSSI value at the moment through a Bluetooth radio frequency bottom layer;

s8: the digital key Bluetooth master module acquires the RSSI acquired by the Bluetooth antenna in S6 through an LIN bus and periodically polls the RSSIs of 3 Bluetooth antennas in a LIN scheduling table mode;

s9: the digital key Bluetooth main module calculates the position of the current mobile phone relative to the vehicle body through a triangulation algorithm by using the 4 RSSI values obtained in S8, and judges whether the mobile phone is in the vehicle, namely a left PE, a right PE, a rear PE and a welcome area.

Further, the working current of the Bluetooth main module and the 3 Bluetooth antennas is less than 100mA, and the quiescent current is less than 1.5 mA.

Further, before the steps are executed, the Bluetooth master module and the Bluetooth radio frequency of the 3 Bluetooth antennas need to complete Bluetooth conduction and antenna efficiency tests, and the fact that the real vehicle Bluetooth receiving sensitivity is consistent in performance is guaranteed.

Furthermore, 3 bluetooth antennas need to be arranged at the front left, front right and tail of the automobile body, and the left and right arrangement positions are symmetrical, and the bluetooth main module and the tail antenna are arranged on the axis of the automobile body.

Furthermore, the bluetooth radio frequency difference of the mobile phone brand needs to be compatible, and the bluetooth performance and parameters of the mobile phone with the mainstream brand need to be calibrated.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

the invention successfully solves the problem that the digital key has the key positioning function with the necessary functions, the hardware cost required by the positioning algorithm is relatively lower, LIN bus communication is adopted, and SBC + BLE is adopted as the Bluetooth antenna; meanwhile, the algorithm has short calculation time and quick response; meanwhile, the algorithm determines that the mobile phone adopts a Bluetooth host scanning mode, so that the compatibility at the mobile phone end is better; meanwhile, the mobile phone end adopts the functions of calibration and calibration, so that the compatibility of the Bluetooth differences of different mobile phone brands is better.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.

Drawings

The drawings of the present invention are described below.

FIG. 1 illustrates the software and hardware requirements of the digital key arrangement of the present invention;

FIG. 2 is a flow chart of a method implementation of the present invention;

FIG. 3 is a schematic diagram of a triangulation method of the present invention.

Detailed Description

In order to make the technical solutions, advantages and objects of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention without any inventive step, are within the scope of protection of the present application.

The invention is further illustrated by the following figures and examples.

Example 1

Referring to fig. 1 to 3, fig. 1 illustrates a hardware layout requirement of a digital key location algorithm based on bluetooth RSSI, which includes the following steps:

s1: the digital key mobile phone APP is used as a Bluetooth host;

s2: the digital key Bluetooth master module is used as a Bluetooth slave;

s3: the digital key Bluetooth antenna scans the broadcast of the digital key mobile phone;

s4: the digital key Bluetooth main module and the Bluetooth rear antenna are arranged on a central axis of the vehicle;

s5: the left and right digital key Bluetooth antennas are symmetrically arranged on the left and right door handles.

The implementation process comprises the following steps:

s1: the digital key mobile phone APP finishes the Bluetooth pairing process of the mobile phone and the digital key main module through a Bluetooth binding process and a Bluetooth broadcast channel of the Bluetooth, only the Bluetooth equipment passing the security authentication is successfully paired, and once the security authentication fails, the Bluetooth pairing is quitted;

s2: after the Bluetooth pairing is completed, the digital key mobile phone APP sends the physical characteristic information of the mobile phone to the digital key main module through a specific GATT data stream;

s3: the digital key main module tells the received mobile phone characteristic information to 3 Bluetooth antennas through the LIN bus; since the characteristic information exceeds the maximum byte 8 of the length of the LIN data frame, the LIN diagnosis mode is needed; the transmission of the transmission layer follows the ISO15765-2 multi-frame transmission principle; the protocol layer conforms to the ISO14229 service standard

S4: after receiving the mobile phone characteristic information, the Bluetooth antenna temporarily stores the mobile phone characteristic information in the RAM, so that the Bluetooth antenna identifies whether the mobile phone is a broadcast message sent by a mobile phone connected with Bluetooth or not through the received mobile phone characteristic information;

s5: the method comprises the steps that a digital key mobile phone APP sends a broadcast packet, and mobile phone feature information is attached to the broadcast packet;

s6: the Bluetooth antenna scans all Bluetooth broadcast packets in a Bluetooth broadcast channel; only the broadcast packet conforming to the mobile phone feature information received in S4 is processed; meanwhile, a radio frequency receiving sensitivity RSSI value sensed when the broadcast packet is received is obtained through a Bluetooth radio frequency bottom layer;

s7: the digital key Bluetooth main module receives a data packet sent by the mobile phone APP through the paired private channel, and can acquire a radio frequency receiving sensitivity RSSI value at the moment through a Bluetooth radio frequency bottom layer;

s8: the digital key bluetooth master module acquires the RSSI acquired by the bluetooth antenna in S6 through the LIN bus. Periodically polling the RSSI of 3 Bluetooth antennas in a LIN scheduling table mode;

s9: the digital key Bluetooth main module calculates the current position of the mobile phone relative to the vehicle body according to the 4 RSSI values through a triangulation algorithm, and judges whether the mobile phone is in the vehicle, a left PE, a right PE, a rear PE, a welcome area and the like.

Finally, the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered in the protection scope of the present invention.