Novel Bluetooth module

Abstract

The utility model discloses a novel Bluetooth module, which relates to the technical field of wireless communication, aims to solve the problem of limitation of the connection number of Bluetooth modules, and comprises a substrate, a chip module is arranged on the substrate, the chip module comprises an integrated chip U1, and the chip module is connected with a crystal oscillator module; the radio frequency module is electrically connected with the chip module, the radio frequency module comprises a matching circuit and an antenna unit, and the matching circuit is connected with the integrated chip U1; the external interface module comprises a data interface and a debugging interface, and the external interface module is connected with external equipment. The Bluetooth module provided by the utility model not only can be used as a host to connect up to 16 slave devices and send and receive data, but also can be used as a Beacon device to broadcast information outwards and be used for positioning, message pushing and the like, so that the connection capability is effectively expanded, and wider application requirements are met.

Description

Technical Field

[0001] The utility model belongs to the technical field of wireless communication, and particularly relates to a new type of Bluetooth module. Background Art

[0002] With the rapid development of the Internet of Things, the demand for Bluetooth modules that can support multi-device connection, data transmission, and positioning functions is increasing day by day. Most of the existing Bluetooth modules on the market can only work as a single role (master or slave), which limits their use in complex application scenarios. In addition, the application of Beacon devices is also increasing, especially in the fields of indoor positioning, advertising push, and smart retail.

[0003] At present, Bluetooth communication is a relatively advanced and widely used transmission method in the Internet of Things industry. With the progress of technology, Bluetooth technology has developed to multiple versions and is relatively mature. However, to develop a Bluetooth module that can support both master and slave modes and has Beacon functions, the following problems still exist:

[0004] 1. Many Bluetooth modules only support a single role (master or slave). Information transfer mainly relies on connections, which limits their application in multi-device interaction scenarios. For example, a device needs to control multiple slave devices simultaneously and serve as a data source for other masters; 2. Limitation of the number of connections. Originally, modules usually can only support a limited number of device connections, interact with and manage a few devices, and it is necessary to fully consider interaction events to ensure the stability and real-time nature of data transmission, making it difficult to meet the requirements for interacting with more devices.

[0005] 3. Problem of connection stability. In cases where the distance is far, interference is high, and the signal is poor, disconnection problems will occur, and users need to manually establish connections, which is very cumbersome in a multi-device environment and affects the user experience. In an environment with unstable signals, devices may frequently disconnect, requiring users to constantly reconnect, and operation errors may also occur, such as connecting to the wrong device.

[0006] For example, there is a Chinese patent with the publication number CN114079901A, which relates to a movable Bluetooth communication module and its usage method. It discloses a movable Bluetooth communication module and its usage method. The overall structure is light and compact, easy to place and hang, and can be connected to up to three different devices simultaneously. The connection port can fit the connection lines of various devices, and the device can be used more safely without malicious data theft, and the central transmission processor can also be used as a center for temporarily storing data. However, the Chinese patent with the publication number CN114079901A can connect to a maximum of 3 different devices, unable to meet the requirements for interacting with more devices, greatly limiting the usage scenarios. Summary of the Invention

[0007] To solve the problem of the connection number limit of the Bluetooth module, the present utility model proposes a new type of Bluetooth module, which can not only be used as a host to connect up to 16 slave devices to send and receive data, but also be used as a Beacon device to broadcast information outward to realize positioning and message pushing functions, effectively expanding the connection ability and meeting a wider range of application requirements.

[0008] To achieve the above object, the present utility model adopts the following technical solutions: A new type of Bluetooth module, comprising:

[0009] A chip module disposed on a substrate, and a crystal oscillator module is connected to the chip module;

[0010] A radio frequency module electrically connected to the chip module, the radio frequency module includes a matching circuit and an antenna unit, and the matching circuit is connected to the integrated chip U1 of the chip module;

[0011] An external interface module disposed on the substrate, including a data interface and a debugging interface, and the external interface module is connected to an external device.

[0012] In this technical solution, the chip module, the radio frequency module, the crystal oscillator module and the external interface module are all disposed on the substrate, and the substrate is a four-layer PCB board.

[0013] The integrated chip U1 is a main control chip, which can achieve multi-role compatibility, can be used as a host and a Beacon device at the same time, can provide a more flexible device connection ability, establish stable connections with multiple devices and perform data exchange. The user can also perform command settings to control the number of various roles, which is convenient and flexible.

[0014] The Bluetooth module further includes a radio frequency module electrically connected to the chip module, and the radio frequency module includes a matching circuit and an antenna unit to realize the sending and receiving of wireless signals.

[0015] The Bluetooth module is also provided with an external interface module, and parameters can be set through serial port commands to realize the function of automatic connection, quickly re-establish a connection with a disconnected device, and maintain stable communication, thereby improving the user experience and connection efficiency.

[0016] The present utility model is further configured as: the matching circuit is a π-shaped matching circuit, one end of the inductor L4 of the matching circuit is connected to the radio frequency pin of the integrated chip U1, and the other end is connected to the antenna unit.

[0017] In this technical solution, the matching circuit uses a π-shaped matching circuit and is placed close to the chip RF pin to realize antenna matching, reducing signal reflection and loss.

[0018] The present utility model is further configured as follows: Both ends of the inductor L4 are respectively connected to a capacitor C9 and a capacitor C11, and the other ends of the capacitor C9 and the capacitor C11 are grounded.

[0019] In this technical solution, the matching circuit is implemented by using an inductor of 3.3 nH and two capacitors of 1.5 pF, ensuring impedance matching.

[0020] The present utility model is further configured as follows: The antenna unit includes an inductor L3. One end of the inductor L3 is respectively connected to the matching circuit and a capacitor, and the other end of the inductor L3 is respectively connected to an antenna and a diode unit. The diode unit includes two zener diodes connected in reverse.

[0021] In this technical solution, the antenna can receive and transmit radio signals. Preferably, the antenna is an on-board PCB antenna, configured as an inverted F shape, placed at the edge of the board, and there are clearance areas on both the front and back sides.

[0022] The present utility model is further configured as follows: The crystal oscillator module includes a crystal oscillator Y1. Both ends of the crystal oscillator Y1 are respectively connected to a capacitor C14 and a capacitor C19, and the other ends of the capacitor C14 and the capacitor C19 are grounded.

[0023] In this technical solution, due to the reasons that the crystal oscillator itself has too large a frequency deviation and poor working temperature stability, it may cause the performance indicators of the FR801xH to decline or even fail to work. The crystal oscillator Y1 is a 24 MHz surface mount crystal oscillator with a frequency tolerance of 10 PPM. The load capacitors C14 and C19 are both 12 pF and are placed close to the crystal oscillator. The outer shell of the surface mount crystal oscillator is grounded, and the performance is stable.

[0024] The present utility model is further configured as follows: The integrated chip U1 is provided with a radio frequency pin and a ground pin, and the matching circuit is connected to the radio frequency pin and the ground pin of the integrated chip U1.

[0025] The present utility model is further configured as follows: The integrated chip U1 is also provided with a crystal oscillator pin, and the crystal oscillator pin is connected to the crystal oscillator module.

[0026] In this technical solution, the crystal oscillator module provides a stable and accurate single-frequency oscillation for the integrated chip U1.

[0027] The present utility model is further configured as follows: The integrated chip U1 is also provided with a power supply pin, and the power supply pin is connected to a power supply.

[0028] In this technical solution, the power supply supplies energy to the integrated chip U1.

[0029] The present utility model is further configured as follows: The data interface and the debugging interface are serial ports. The data interface conducts data communication with external devices, and the debugging serial port outputs the operation status and content of the module in real time.

[0030] In this technical solution, the user can communicate with the module through the data serial port to complete parameter setting and information sending and receiving. The debugging serial port can output the operation status and content of the module in real time, facilitating the user to understand the module situation and make settings.

[0031] The present utility model is further configured as: the model of the integrated chip U1 is FR8016HA.

[0032] The beneficial effects of the present utility model are:

[0033] 1. Support for multiple roles: Compatible with multiple roles, capable of acting as both a host and a Beacon device simultaneously, providing more flexible device connection capabilities, establishing stable connections with multiple devices and exchanging data. The user can also perform instruction settings to control the number of various roles, which is convenient and flexible, meeting the usage scenarios when a device needs to control multiple slave devices simultaneously and serve as a data source for other hosts;

[0034] 2. Support for multiple devices: Breaking through the limitation of the connection number, achieving stable connection of up to 16 slave devices simultaneously, effectively expanding the connection capabilities and meeting broader application requirements;

[0035] 3. Stable connection: Designed with an automatic reconnection function, capable of quickly re - establishing a connection to a disconnected device and maintaining stable communication,

[0036] thus improving the user experience and connection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is the circuit schematic diagram of a new type of Bluetooth module of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] To make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only the best embodiments of the present utility model, only used to explain the present utility model, and do not limit the protection scope of the present utility model. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present utility model.

[0039] Although Bluetooth technology is already quite mature, there are still the following problems in developing a Bluetooth module that can support both the host and slave modes simultaneously and has the Beacon function.

[0040] First, many Bluetooth modules only support a single role (host or slave), and information transmission is mainly through connection, which limits their application in multi-device interaction scenarios. For example, when a device needs to control multiple slave devices at the same time and serve as a data source for other hosts.

[0041] The second is the limitation on the number of connections. The original module usually only supports a limited number of device connections. Information exchange and management of a few devices need to be fully considered to ensure the stability and real-time nature of data transmission. It is difficult to meet the needs of more devices that need to interact.

[0042] The third is the problem of connection stability. In the case of long distance, high interference and poor signal, disconnection problems may occur, and users need to manually establish a connection, which is very cumbersome in a multi-device environment and affects the user experience. In an environment with unstable signals, devices may frequently disconnect, requiring users to constantly reconnect, and operational errors may also occur, such as connecting to the wrong device.

[0043] The utility model aims to develop a new type of Bluetooth module, which can not only act as a host to connect up to 16 slave devices to send and receive data, but also act as a Beacon device to broadcast information to the outside to achieve positioning and message push functions.

[0044] This Bluetooth module can be easily applied to the Internet of Things. By setting parameters with simple instructions, the corresponding functions can be completed, and the output information is complete, which can effectively reduce the user-side code and reduce the difficulty of development. In addition, the easy-to-use characteristics of Bluetooth make Bluetooth devices sufficient, which greatly increases the use scenarios of the utility model solution, whether it is garage positioning or environmental monitoring, it can be effectively used.

[0045] The module has a flexible control method and is controlled through the serial port and function pins. Using this module, users do not need to pay attention to the complex Bluetooth protocol and can develop standard BLE products in a short period of time.

[0046] This embodiment provides a new type of Bluetooth module, which is applied to the development of parking lot camera ground locking positioning scenarios.

[0047] In this embodiment, the camera is installed between two parking spaces in the parking lot. The camera can rotate to take pictures of the front and rear parking spaces in turn to achieve parking space recognition and license plate recognition.

[0048] The camera is in a state of long-term capture and analysis and recognition, and can identify the entry and exit of vehicles in parking spaces, as well as license plate information and parking duration at any time.

[0049] In some other embodiments, the camera may be a low-position video pole with two cameras that can simultaneously capture the front and rear parking spaces.

[0050] In some other embodiments, the camera can be a high-position video pile, and one high-position video pile can manage multiple parking spaces simultaneously. The ground lock is a flat ground lock, and the ground locks are arranged in one-to-one correspondence with the parking spaces.

[0051] In some other embodiments, the ground lock can also be a U-shaped ground lock or a D-shaped ground lock.

[0052] The Bluetooth module includes a substrate and a chip module. Among them, the substrate is a PCB board, which is a four-layer PCB board in this embodiment, and in some other embodiments, it can also be more than four layers.

[0053] As Figure 1 shown in the circuit schematic diagram of the new Bluetooth module, the chip module includes an integrated chip U1, that is, the main control chip. The low-power Bluetooth chip FR801xH series chips, which are easy to develop quickly for SOC (System on Chip), are selected. Specifically, it is FR8016HA of Furui Kun. This chip supports up to 20 connections and can perform broadcast and scan operations while connected.

[0054] This chip has the support of the Bluetooth smart firmware and protocol stack of Freqchi and is fully compatible with the Bluetooth V5.1 (LE mode) protocol. At the same time, users can develop various application programs based on the built-in ARM CorteM3 embedded 32-bit high-performance microcontroller of the chip.

[0055] Based on the development of this chip, multi-role compatibility can be achieved. The Bluetooth module can simultaneously act as a host and a Beacon device, providing more flexible device connection capabilities, establishing stable connections with multiple devices and performing data exchange. Users can also perform instruction settings to control the number of various roles, which is convenient and flexible.

[0056] The chip module is connected to a crystal oscillator module. The crystal oscillator module includes a crystal oscillator Y1. Capacitor C14 and capacitor C19 are respectively connected to both ends of the crystal oscillator Y1, and the other ends of capacitor C14 and capacitor C19 are grounded.

[0057] Specifically, the crystal oscillator Y1 selects a 24MHz surface mount crystal oscillator with a frequency tolerance of 10PPM. The load capacitors C14 and C19 are both 12pF and are placed close to the crystal oscillator.

[0058] Due to the reasons of excessive frequency deviation of the crystal oscillator itself and poor working temperature stability, it may cause the performance indicators of the main control chip to decline or even fail to work. Therefore, a surface mount crystal oscillator with a grounded shell is selected to make the performance more stable.

[0059] The crystal oscillator module provides a stable and accurate single-frequency oscillation for the integrated chip U1 and inputs it as a clock signal. In this embodiment, the clock frequency is 24MHz.

[0060] The integrated chip U1 is provided with a crystal oscillator pin, and the crystal oscillator pin is connected to a crystal oscillator module.

[0061] The Bluetooth module further includes a radio frequency module, and the radio frequency module includes a matching circuit and an antenna unit, and the matching circuit is a π-shaped matching circuit.

[0062] The matching circuit is implemented by using an inductor of 3.3 nH and two capacitors of 1.5 pF, ensuring impedance matching.

[0063] The matching circuit includes an inductor L4. One end of the inductor L4 is connected to the radio frequency pin of the integrated chip U1, and the other end is connected to the antenna unit.

[0064] Both ends of the inductor L4 are further respectively connected with a capacitor C9 and a capacitor C11, and the other ends of the capacitor C9 and the capacitor C11 are grounded.

[0065] Pin 5 (RF pin) of the FR8016HA chip is a radio frequency pin. The matching circuit is placed close to the chip RF pin to achieve antenna matching, reducing signal reflection and loss.

[0066] The antenna unit includes an inductor L3. The inductor L3 is 220 pF. One end of the inductor L3 is respectively connected to the matching circuit and a capacitor, and the other end of the inductor L3 is respectively connected with an antenna and a diode unit. The diode unit includes two zener diodes connected in reverse.

[0067] The antenna is used to receive and transmit radio signals. Preferably, the antenna is a board-mounted PCB antenna, set to an inverted F shape, placed at the edge of the board, and there are clearance areas on both the front and back sides.

[0068] The integrated chip U1 is provided with a radio frequency pin and a ground pin, and the matching circuit is connected to the radio frequency pin and the ground pin of the integrated chip U1.

[0069] After the PCB board is drawn, frequency offset calibration and antenna matching calibration are performed on the radio frequency performance.

[0070] The crystal oscillator module provides stable and accurate single-frequency oscillation for the integrated chip U1.

[0071] The Bluetooth module further includes an external interface module. The external interface module includes a data interface and a debugging interface, and the external interface module is connected to external devices.

[0072] All GPIO pins of the Fr801xH series chips are defaulted to a low voltage except for PA2 and PA3 when powered on. The Rom Code of the chip initializes PA2 and PA3 to the RXD pin and TXD pin (baud rate 115200) of the UART1 serial port by default. And the PA3 pin will print the character of freq once.

[0073] In this embodiment, the data interface and the debugging interface are serial ports. The data interface communicates with external devices, and the debugging serial port outputs the operation status and content of the module in real time.

[0074] Users can communicate with the module through the data serial port to complete parameter settings and information sending and receiving. The debugging serial port can output the operation status and content of the module in real time, facilitating users to understand the module situation and make settings.

[0075] This technical solution sets parameters through serial port commands, enables broadcasting and scanning at the same time. If the name of the device to be connected is scanned, an active connection is made. If connected by the host device, it can send a broadcast again and be connected again.

[0076] The function of automatic connection is realized, quickly re - establishing a connection for the disconnected device, maintaining stable communication, thereby improving the user experience and connection efficiency.

[0077] In addition, the low - power function can be achieved by switching the external mode control pin, thereby extending the working time.

[0078] In this embodiment, the automatic re - connection function is combined with position awareness to achieve more intelligent device management, improving the convenience and reliability of operation.

[0079] In some other embodiments, this function can be combined with some other intelligent functions (such as environmental monitoring) to achieve some other intelligent management.

[0080] Correspondingly, the chip can work in two modes: user mode and production test mode.

[0081] Specifically, the slave end adds HID (Human Interface Device). After the system initialization, the user can judge the mode. If it is the user mode, the serial port initialization and protocol parameter initialization will be carried out, and then the event - handling functions will be loaded to handle disconnection, connection, serial port command, and scanning events.

[0082] When a disconnection event occurs, the device of this disconnection will be judged. If it is a device that needs automatic connection, a connection will be initiated for this device; after successful connection, it can notify the MCU through the serial port that the connection has been completed and data communication can be carried out.

[0083] The serial port event is processed using the serial port command processing function. Users can set and query the parameters or communication of the module through the serial port, including but not limited to serial port baud rate, Beacon information parameters, connection quantity, and role configuration parameters. Here, an easy - to - use serial port command format is also defined to facilitate user operation.

[0084] The parameters of the beacon broadcast content can be set using serial port instructions to implement functions including but not limited to positioning.

[0085] The integrated chip U1 is also provided with a power pin, and the power pin is connected to a power supply, which powers the integrated chip U1.

[0086] The positioning of the ground lock in the parking lot belongs to indoor positioning. In the environment of indoor positioning, the commonly used GPS outdoor positioning has great limitations. On the one hand, the GPS signal power is extremely low, and the reception requirements are quite high. Only when the antenna is unobstructed to the sky can the satellite signal be received and positioning be achieved. On the other hand, due to the characteristics of modern building materials, the GPS signal is easily blocked or reflected by the wall and cannot enter the indoor smoothly, resulting in the inability to receive the satellite signal and the inability to achieve positioning indoors.

[0087] With the continuous maturity and development of BLE (Bluetooth Low Energy Technology), Bluetooth positioning technology can be widely applied to indoor positioning scenarios.

[0088] Apply the Bluetooth module to the ground lock and camera to implement the positioning function.

[0089] The Bluetooth modules of the ground lock and camera obtain the cloud platform control signal to control the ground lock and camera, and monitor the parking space usage status information and upload it to the cloud platform.

[0090] The cloud platform server stores the parking space status, location, opening time period, user parking time information, and the calculation of parking fees.

[0091] In some embodiments, the Bluetooth module can be combined with a mobile APP or a small program, and cooperate with the cloud platform server. Through three-terminal communication, the APP or the small program can obtain the parking space status from the cloud platform server, and then implement functions such as setting the parking space sharing time period, querying the parking space, reserving the parking space, remotely controlling the unlocking, and paying the parking fee.

[0092] On the premise of ensuring safety, realize the shared management of parking spaces and improve the turnover rate of parking space resources. It brings great convenience to the parking lot management and users' use of parking spaces.

[0093] The user holding the parking space can set the corresponding opening and sharing time period through the APP according to the usage or management of the parking space, and can view the parking space usage and income situation in real time.

[0094] The user looking for a parking space can view the parking space situation near the current location or at the travel destination through the APP, reserve the parking space according to their own needs, and can open the parking space lock through the APP after arriving at the destination, realizing fast parking and paying the fee after use.

[0095] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to enumerate all the implementation manners here. Any obvious changes or modifications derived from the technical solutions of the present utility model still fall within the protection scope of the present utility model.

Claims

1. A new type of Bluetooth module, characterized by: include: A chip module is arranged on the substrate, wherein the chip module is connected to a crystal oscillator module; A radio frequency module electrically connected to the chip module, the radio frequency module comprising a matching circuit and an antenna unit, the matching circuit being connected to the integrated chip U1 of the chip module; The external interface module arranged on the substrate includes a data interface and a debugging interface, and the external interface module is connected to an external device.

2. A novel Bluetooth module according to claim 1, characterized in that: The matching circuit is a π-shaped matching circuit, one end of the inductor L4 of the matching circuit is connected to the radio frequency pin of the integrated chip U1, and the other end is connected to the antenna unit.

3. A novel Bluetooth module according to claim 2, characterized in that: The two ends of the inductor L4 are connected to a capacitor C9 and a capacitor C11 respectively, and the other ends of the capacitor C9 and the capacitor C11 are grounded.

4. A novel Bluetooth module according to claim 1, characterized in that: The antenna unit includes an inductor L3, one end of the inductor L3 is respectively connected to a matching circuit and a capacitor, and the other end of the inductor L3 is respectively connected to an antenna and a diode unit, and the diode unit includes two reversely connected zener diodes.

5. The novel Bluetooth module according to claim 1, characterized in that: The crystal oscillator module includes a crystal oscillator Y1 , two ends of the crystal oscillator Y1 are connected to a capacitor C14 and a capacitor C19 respectively, and the other ends of the capacitor C14 and the capacitor C19 are grounded.

6. A novel Bluetooth module according to claim 1 or 3, characterized in that: The integrated chip U1 is provided with a radio frequency pin and a ground pin, and the matching circuit is connected to the radio frequency pin and the ground pin of the integrated chip U1.

7. A novel Bluetooth module according to claim 1 or 3, characterized in that: The integrated chip U1 is also provided with a crystal oscillator pin, and the crystal oscillator pin is connected to a crystal oscillator module.

8. A novel Bluetooth module according to claim 1 or 3, characterized in that: The integrated chip U1 is also provided with a power pin, and the power pin is connected to a power source.

9. The novel Bluetooth module according to claim 1, characterized in that: The data interface and the debugging interface are both serial ports. The data interface performs data communication with external devices, and the debugging serial port outputs the module operation status and content in real time.

10. A novel Bluetooth module according to any one of claims 1 to 5, characterized in that: The model of the integrated chip U1 is FR8016HA.

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