Radio frequency positioning based play-by-play machine scenic spot explanation system

Abstract

The utility model belongs to the technical field of electronic guide machine, disclose a kind of based on radio frequency positioning's broadcast machine scenic spot explanation system. The system includes radio frequency unit, central processing unit (CPU), storage unit, power supply unit, reset unit and level conversion unit. Radio frequency unit receives the only position identification code sent by scenic spot transmitter;CPU will the identification code with the scenic spot data table pre-stored in storage unit match, if match succeeds then the corresponding scenic spot explanation information is extracted and control plays. Power supply unit is started and stopped by CPU control, reset unit is reset to radio frequency chip by CPU control, and level conversion unit realizes the serial port level matching between radio frequency chip and CPU. The scheme is matched by accurate radio frequency positioning and automatic information, solves the problem that electronic guide machine is not accurate in the prior art, information acquisition and matching logic is not clear, and the lack of effective control of each functional unit leads to the problem that overall collaborative work is not clear, improves the reliability and energy efficiency of tour experience and system.

Description

Technical Field

[0001] This utility model belongs to the technical field of electronic tour guide devices, specifically relating to a portable electronic broadcasting device that uses radio frequency technology for positioning and automatically plays introductions to tourist attractions. Background Technology

[0002] In tourist attractions and museums, guided tours are often provided to visitors. Currently, this is typically done by human guides or electronic guide devices. Electronic guide devices can store multilingual descriptions of attractions, playing pre-recorded audio guides when visitors select a particular attraction, reducing the need for human guides. However, traditional electronic guide devices often require visitors to manually enter numbers or make selections, making them less intuitive and convenient to use.

[0003] Existing technologies already include solutions for automatically triggering guided tours at tourist attractions using wireless sensing methods such as RFID. For example, Chinese patent document CN201378412Y discloses an electronic self-guided tour guide system. This system includes a handheld tour guide device, wireless area triggers, and RFID cards corresponding to each attraction. The scenic area is divided into several zones, with a wireless area trigger at the center of each zone to emit a signal recognizable by the tour guide device. RFID cards with attraction numbers are placed at each attraction. The tour guide device automatically identifies the attraction and plays the corresponding guided tour information by receiving signals from the area triggers or sensing the RFID cards. This solution reduces the amount of manual intervention required from tourists and increases the automation level of the guided tours.

[0004] However, the existing solutions still have some shortcomings: First, multiple wireless area trigger devices need to be deployed within the scenic area, which not only increases the cost of system deployment but also increases the complexity of equipment maintenance; second, for RFID cards at attractions, the tour guide device must be at a very close distance to read them, resulting in a limited identification range, and tourists still need to bring the device close to the tag, which limits its use; in addition, the system's broadcasting equipment also has room for improvement in terms of audio output methods and power supply, for example, traditional devices mostly use wired headphones for output and have simple charging management, which may affect the tourist experience and equipment reliability.

[0005] In view of the above problems, there is an urgent need for an improved automatic explanation system for scenic spots to further reduce the difficulty of setting up the system, expand the RFID identification range, and improve the audio broadcasting effect and the power supply management performance of the equipment. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a radio frequency positioning-based audio guide system for scenic spots. This system can obtain unique location identifiers of scenic spots through a clear radio frequency positioning mechanism, and has clear data matching logic and a complete system unit collaborative working mechanism, thereby achieving accurate and reliable automatic audio guide functions.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A radio frequency positioning-based audio guide system for tourist attractions includes: The radio frequency unit is configured to receive a unique location identifier code representing the location of a scenic spot, which is sent by a radio frequency transmitter preset at the scenic spot. A central processing unit (CPU), electrically connected to the radio frequency unit, is used to process the unique location identifier code; A storage unit is electrically connected to the central processing unit (CPU). The storage unit pre-stores a scenic spot data table, which contains the scenic spot name and scenic spot description information corresponding to the unique location identifier. The power supply unit is electrically connected to the radio frequency unit and the central processing unit (CPU) to provide operating power to the radio frequency unit and the central processing unit (CPU); A reset unit, electrically connected to the radio frequency unit and the central processing unit (CPU), is used to reset the radio frequency unit according to the instructions of the central processing unit (CPU). A level conversion unit is disposed between the radio frequency unit and the central processing unit (CPU) for level conversion of the serial communication signals between them; The central processing unit (CPU) is further configured to perform the following operations: (a) Obtain the received unique location identifier code from the radio frequency unit; (b) Match the obtained unique location identifier with the unique location identifier in the pre-stored scenic spot data table in the storage unit; (c) If a match is found, the name of the attraction and the description of the attraction corresponding to the unique location identifier are extracted from the attraction data table; (d) Control the audio playback component to play the explanation information of the scenic spot.

[0008] A radio frequency (RF) positioning-based tourist attraction explanation system includes an RF unit, a central processing unit (CPU), a storage unit, a power supply unit, a reset unit, and a level conversion unit. The RF unit is configured to receive a unique location identifier code representing the location of a tourist attraction, transmitted by an RF transmitter pre-installed at the attraction. The CPU is electrically connected to the RF unit and processes the unique location identifier code. The storage unit is electrically connected to the CPU and pre-stores a tourist attraction data table containing the name of the attraction and its explanation information corresponding to the unique location identifier code. The power supply unit provides operating power to the RF unit and the CPU. The reset unit resets the RF unit according to instructions from the CPU. The level conversion unit is located between the RF unit and the CPU and is used for level conversion of serial communication signals between them. The CPU is also configured to retrieve the unique location identifier code from the RF unit, match it with the tourist attraction data table, and if successful, extract the corresponding information and control the audio playback component to play it.

[0009] Preferably, the radio frequency unit includes a radio frequency chip, power supply filter capacitors (a first capacitor and a second capacitor), a 2.4G ceramic antenna, and an antenna matching network (composed of a third capacitor and a first resistor) connecting the antenna pins of the radio frequency chip to the ceramic antenna. This configuration ensures effective reception of radio frequency signals and stable operation of the radio frequency chip.

[0010] Furthermore, the power supply unit includes a voltage regulator chip, an input filter capacitor (the fifth capacitor), an output filter capacitor (the sixth capacitor), and an enable control circuit that controls the enable terminal of the voltage regulator chip via resistors (the eighth and ninth resistors) from the CPU's GPIO pins. This design enables the CPU to actively manage the power consumption of units such as the radio frequency unit, improving energy efficiency.

[0011] Preferably, the reset unit includes an N-type field-effect transistor (a third N-type field-effect transistor), whose drain is connected to the reset pin of the RF chip and pulled up by a pull-up resistor (the twelfth resistor), and whose gate is controlled by the CPU's GPIO pin through resistors (the tenth and eleventh resistors). This design allows the CPU to reliably perform a hardware reset of the RF chip when needed.

[0012] Preferably, the level conversion unit includes two unidirectional or bidirectional level conversion channels composed of N-type field-effect transistors (a first N-type field-effect transistor and a second N-type field-effect transistor) and corresponding pull-up and drive resistors, respectively used for serial port signal level conversion from the CPU to the RF chip and from the RF chip to the CPU. This ensures correct communication between modules with different operating levels.

[0013] The beneficial effects of this utility model are: 1. Significantly improves the convenience and effective range of attraction identification, and is expected to simplify the deployment of equipment in scenic areas: This invention's broadcasting system receives a unique location identifier code sent by a pre-installed radio frequency transmitter at a scenic spot via its radio frequency unit. This design allows the broadcasting system to automatically sense and obtain a precise code representing the current location of the scenic spot within a certain distance, eliminating the need for extremely close contact with the tag, as required by existing RFID cards. Therefore, tourists using this broadcasting system do not need to deliberately search for or approach the sensing point; simply entering the signal coverage area of ​​the radio frequency transmitter automatically completes location identification, greatly improving the naturalness and convenience of use. Compared to existing solutions that require RFID cards at each scenic spot and may be supplemented by area triggers, if the radio frequency technology used in this solution has a suitable coverage distance, it is possible to achieve effective coverage of the scenic area with fewer transmitters, thereby simplifying the deployment of positioning devices within the scenic area and potentially reducing related installation and maintenance costs.

[0014] 2. It enhanced the overall controllability and operational stability of the broadcasting system and laid the foundation for optimized energy consumption management: The central processing unit (CPU) of this invention not only processes location information and matches scenic spot data, but also directly manages and controls the power supply unit and reset unit within the system. Specifically, the CPU can issue instructions to the power supply unit according to preset logic or real-time status, enabling on-demand power supply to modules such as the radio frequency unit or entry into a low-power mode. This creates conditions for refined power management and extended broadcaster battery life, effectively responding to the need for improved power supply and battery life performance in existing technologies. Furthermore, the CPU's control over the reset unit allows the system to proactively execute a hardware reset operation when the radio frequency unit or other critical components malfunction, prompting the equipment to recover from potential fault states, thereby ensuring the long-term stable operation and reliability of the broadcaster. This CPU-led direct control mechanism over critical hardware units ensures more efficient and orderly collaboration among the various components of the system, improving the integration and robustness of the entire electronic system.

[0015] Through the above improvements, this utility model provides a more advanced automatic tour guide system for scenic spots. It not only makes breakthroughs in the convenience and range of positioning and identification, but also optimizes the power management, operational stability and overall collaborative work of the system. As a result, it can bring a better tour experience to tourists and provide scenic spot managers with a more efficient solution for deployment and maintenance. Attached Figure Description

[0016] Figure 1 This is a circuit diagram of the radio frequency unit of this utility model; Figure 2 This is a circuit diagram of the power supply unit of this utility model; Figure 3This is a circuit diagram of the level conversion unit of this utility model; Figure 4 This is a circuit diagram of the reset unit of this utility model; Figure 5 This is a partial pin diagram for circuit testing of this utility model. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It is understood that the accompanying drawings are provided for reference and illustration only, and are not intended to limit the present invention. The connection relationships shown in the accompanying drawings are only for clear description and do not limit the connection method.

[0018] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. The terminology used in this specification is only for the purpose of describing specific embodiments and is not intended to limit the invention.

[0019] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0020] like Figures 1-5 As shown in this embodiment, a radio frequency positioning-based audio guide system for scenic spots is provided. Its core idea is to pre-install fixed low-power radio frequency transmitters at various independent scenic spots or key locations within the scenic area. Each transmitter is configured to periodically or when queried broadcast a unique string or numerical code. This code is what this solution refers to as the "unique location identifier," which forms a one-to-one correspondence with the physical location of the transmitter (i.e., the scenic spot).

[0021] A radio frequency positioning-based audio guide system for tourist attractions includes: The radio frequency unit is configured to receive a unique location identifier code representing the location of a scenic spot, which is sent by a radio frequency transmitter preset at the scenic spot. A central processing unit (CPU), electrically connected to the radio frequency unit, is used to process the unique location identifier code; A storage unit is electrically connected to the central processing unit (CPU). The storage unit pre-stores a scenic spot data table, which contains the scenic spot name and scenic spot description information corresponding to the unique location identifier. The power supply unit is electrically connected to the radio frequency unit and the central processing unit (CPU) to provide operating power to the radio frequency unit and the central processing unit (CPU); A reset unit, electrically connected to the radio frequency unit and the central processing unit (CPU), is used to reset the radio frequency unit according to the instructions of the central processing unit (CPU). A level conversion unit is disposed between the radio frequency unit and the central processing unit (CPU) for level conversion of the generated serial communication signals; The central processing unit (CPU) is further configured as follows: (a) Obtain the received unique location identifier code from the radio frequency unit; (b) Match the obtained unique location identifier with the unique location identifier in the pre-stored scenic spot data table in the storage unit; (c) If a match is found, the name of the attraction and the description of the attraction corresponding to the unique location identifier are extracted from the attraction data table; (d) Control the audio playback component to play the explanation information of the scenic spot.

[0022] Preferably, the radio frequency unit includes: Radio frequency chip (U909); The first capacitor (C1) and the second capacitor (C2) are connected in parallel between the power supply pin (9) of the RF chip (U909) and ground for power supply filtering. 2.4G ceramic antenna (L908); and The antenna matching network, consisting of a third capacitor (C3) and a first resistor (R1) connected in series or in parallel, is connected between the antenna pin (22) of the RF chip (U909) and the input pin (1) of the 2.4G ceramic antenna (L908).

[0023] Preferably, the power supply unit includes: The voltage regulator chip (U905) has an input pin (1) that receives the main power supply of the system and an output pin (5) that outputs a stable operating voltage to the radio frequency unit and the central processing unit (CPU). The fifth capacitor (C5) is connected between the input pin (1) of the voltage regulator chip (U905) and ground for input filtering; The sixth capacitor (C6) is connected between the output pin (5) of the voltage regulator chip (U905) and ground for output filtering; The enable control circuit includes an eighth resistor (R8) and a ninth resistor (R9). One end of the ninth resistor (R9) is connected to the GPIO pin of the central processing unit (CPU), and the other end, together with the eighth resistor (R8), is connected to the enable pin (3) of the voltage regulator chip (U905). This allows the central processing unit (CPU) to control the start and stop of the voltage regulator chip (U905) through the GPIO pin.

[0024] Preferably, the reset unit includes: The third N-type field-effect transistor (Q3) has its source grounded and its drain connected to the reset pin (8) of the RF chip (U909) in the RF unit. The twelfth resistor (R12) is connected at one end to the operating power supply and at the other end to the drain of the third N-type field-effect transistor (Q3) to pull up the reset pin (8). The gate control circuit includes a tenth resistor (R10) and an eleventh resistor (R11). One end of the tenth resistor (R10) is connected to the GPIO pin of the central processing unit (CPU), and the other end, together with the common terminal of the eleventh resistor (R11), is connected to the gate of the third N-type field-effect transistor (Q3). The other end of the eleventh resistor (R11) is grounded. The CPU controls the conduction and cutoff of the third N-type field-effect transistor (Q3) through the GPIO pin, thereby controlling the reset of the RF chip (U909).

[0025] Preferably, the level conversion unit includes: The first level conversion channel is used to convert the low-level serial port signal output by the central processing unit (CPU) into the high-level serial port signal required by the radio frequency unit. The first level conversion channel includes a first N-type field-effect transistor (Q1), whose source is connected to the serial port transmit pin (U2RXD / GPIO20) of the central processing unit (CPU), and whose drain is connected to the serial port receive pin (UART_TX, pin 3) of the radio frequency chip (U909) in the radio frequency unit. It is configured as a pull-up and gate drive by a second resistor (R2), a third resistor (R3) and a fifth resistor (R5). The second level conversion channel is used to convert the high-level serial port signal (UART_RX, pin 4) output by the RF chip (U909) in the RF unit into the low-level serial port signal (U2TXD / GPIO21) required by the central processing unit (CPU). The second level conversion channel includes a second N-type field-effect transistor (Q2), whose drain is connected to the serial port transmit pin (UART_RX, pin 4) of the RF chip (U909), and whose source is connected to the serial port receive pin (U2TXD / GPIO21) of the central processing unit (CPU). It is configured as a pull-up and gate drive by the fourth resistor (R4), the sixth resistor (R6), and the seventh resistor (R7).

[0026] The advantages of this solution are: 1. It solved the problems of ambiguous positioning information and unclear processing logic, achieving precise positioning and information matching: This solution explicitly defines that the radio frequency unit receives a "unique location identifier," and the CPU "matches" this "unique location identifier" with a pre-stored "attraction data table" (containing the correspondence between unique location identifiers and attraction information) in the storage unit. If successful, the information is retrieved and played. Because the definition of location information and subsequent processing logic in existing technologies are ambiguous, positioning and information triggering are unreliable. This invention fundamentally clarifies the substantive content of location information by introducing a specific and identifiable numerical or character code—the "unique location identifier"—as the carrier of location information. Simultaneously, through the explicit "table lookup and matching" logic executed by the CPU, a direct and unambiguous mapping relationship is established between the received precise location identifier and the pre-stored attraction explanation content. This completely solves the technical problem in the background technology where ambiguous location information and unclear matching logic prevent accurate triggering of the corresponding explanation, ensuring that the broadcaster can accurately identify the current attraction and play the correct explanation content.

[0027] 2. It resolved the issue of unclear implementation methods for the collaborative work of various functional units in the system, thereby improving the overall reliability and controllability of the system: This solution further specifies that both the power supply unit and the reset unit are electrically connected to and controlled by the CPU. It also defines the enable control circuit for the power supply unit, clarifying that the CPU controls the start and stop of the voltage regulator chip via GPIO. The solution defines the gate control circuit for the reset unit, clarifying that the CPU controls the field-effect transistor via GPIO to reset the RF chip. Because existing technologies often neglect the specific control logic of these auxiliary but critical circuit units, system integration and reliability are low. This invention, by clearly defining the CPU's enable control of the power supply unit, enables on-demand power supply to high-power modules such as the RF module, effectively reducing overall power consumption and extending battery life. Through precise CPU control of the reset unit, proactive hardware reset can be performed when the RF module malfunctions, improving the system's fault tolerance and stability. These specific control mechanisms ensure that the system components are no longer isolated modules, but rather an organic whole that is uniformly scheduled and collaboratively worked by the CPU. This solves the problems of system unreliability and inefficient power management caused by the lack of clear collaborative control mechanisms in the background technology, making the entire broadcasting system more stable, efficient, and easier to manage.

[0028] 3. It provides a clear and implementable circuit structure, facilitating engineering implementation: This solution details the specific circuit components for the RF unit's antenna matching, the power supply unit's filtering and enabling, the reset unit's driving, and the level conversion unit. Existing technologies often lack sufficient description of specific circuit details, increasing implementation difficulty. This invention provides a clear and complete hardware implementation blueprint for those skilled in the art by explicitly describing the specific circuit connections of each key unit and the main components (such as the specific connection methods and functions of capacitors, resistors, and MOSFETs). This elevates the entire system solution beyond the conceptual level, making it highly engineering-feasible, lowering the development and production threshold, and ensuring that the stated functions can be implemented through specific electronic circuits.

[0029] In summary, this utility model effectively overcomes the problems of fuzzy positioning, unclear logic, and poor coordination in the background technology by defining a clearly defined positioning information carrier, a clear information matching logic, and a specific system unit collaborative control and circuit implementation method. It provides a reliable, stable, and easy-to-implement radio frequency positioning-based scenic spot explanation system.

[0030] In detail: RF unit (reference) Figure 1 ): This unit is responsible for receiving a unique location identifier from the site transmitter. The core component is the radio frequency chip U909 (such as the FSC-BT671 or a similar 2.4GHz radio frequency transceiver chip).

[0031] Power supply section: The power supply pin 9 (VDD) of U909 is connected to the system 3.3V power supply, and is grounded after being filtered in parallel by a first capacitor C1 (e.g., 10μF, for stabilizing large current fluctuations) and a second capacitor C2 (e.g., 0.1μF, for high frequency decoupling) to ensure a clean and stable power supply.

[0032] Antenna section: Antenna pin 22 (ANT) of the U909 is connected to the signal input terminal (pin 1) of the 2.4G ceramic antenna L908 via a PI or L-type antenna matching network. (See attached image) Figure 1 The diagram shows a simple matching structure consisting of a third capacitor C3 (e.g., 1pF, in series or parallel, for impedance matching) and a first resistor R1 (e.g., 0Ω as a jumper, or a small resistor for fine-tuning matching or ESD protection). Pins 2 and 3 of the 2.4G ceramic antenna L908 are grounded and connected to the circuit board ground plane. Good antenna matching ensures optimal signal reception sensitivity.

[0033] Communication interface: Pin 3 (UART_TX) and pin 4 (UART_RX) of U909 are serial asynchronous communication interfaces used to send received data (i.e. unique location identifier) ​​to the CPU or to receive control instructions from the CPU.

[0034] Other pins: Pin 8 (RESET) is the reset input. Pins 11 (SWCLK) and 12 (SWDIO) are standard SWD debug interfaces, brought out through test points TP918 and TP915 for easy development and debugging. See attached... Figure 5 These debug interface signals, along with other key test signals or power points, such as test point TP918 corresponding to SWCLK, test point TP915 corresponding to SWDIO, test point TP912 possibly connected to UART_TX, test point TP914 possibly connected to VDD power, TP913 possibly connected to GND, and TP916 possibly connected to the RESET signal, etc., are pre-reserved metal pads or vias on the PCB board. These allow for easy connection using tools such as oscilloscopes, logic analyzers, and debuggers during development, production testing, or troubleshooting to monitor signal waveforms, verify level states, or perform program debugging. For example, TP918 and TP915 can be used to connect J-Link or ST-Link debuggers to program and debug the firmware inside the RF chip U909 (if it is a SoC-type RF chip with an MCU core). TP912 can be used to monitor the data sent by the RF chip to the CPU.

[0035] Central Processing Unit (CPU): Not shown separately in the accompanying drawings, but serving as the "brain" of the entire system, it can be a low-power microcontroller (MCU) such as the STM32 series, or a SoC chip like the UIS8910 mentioned in this solution, which possesses sufficient processing power and GPIO resources. The CPU connects to other units in the system through its GPIO and UART ports, performing the following core tasks: Control the start and stop of the power supply unit.

[0036] The control reset unit resets the radio frequency chip U909.

[0037] The system communicates with the radio frequency chip U909 via the UART interface to obtain the received unique location identifier code.

[0038] Access the storage unit and match the obtained unique location identifier with the pre-stored attraction data table.

[0039] Based on the matching results, control the audio playback component (such as an audio amplifier driven by PWM output, or an audio codec chip connected by an I2S interface) to play the corresponding scenic spot explanation audio.

[0040] Storage unit: Typically, this is non-volatile memory, such as onboard SPI Flash or Nor Flash chips, or Flash integrated within the CPU. Used for storage: Attraction Data Table: This is a crucial data structure, which can be a simple lookup table or a small database. Each record in the table contains at least two key pieces of information: a "unique location identifier" (e.g., the string "JINGDIAN_A001") and the corresponding "attraction description information" (e.g., the name or path of an audio file, "audio / jingdian_a001.mp3", or simply the text description). It may also include other auxiliary information such as the attraction name, image index, etc.

[0041] System firmware: i.e. the program code that the CPU runs.

[0042] Power supply unit (reference) Figure 2 ): This unit is responsible for providing a stable and clean power supply to the system. The core component is the U905 voltage regulator chip (e.g., BL9198-33BAPRN, a low dropout linear regulator (LDO) with an output of 3.3V).

[0043] Input: Input pin 1 (VIN) of the U905 is connected to the system's main power supply (e.g., from a lithium battery or USB power source, after initial processing). A fifth capacitor C5 (e.g., 10μF) is connected between VIN and ground for input filtering, absorbing ripple and noise from the preceding power supply.

[0044] Output: Pin 5 (VOUT) of the U905 outputs a stable 3.3V voltage, supplying the RF chip U909, some CPU I / O, and other devices requiring 3.3V power. A sixth capacitor C6 (e.g., 10μF, with the ESR as low as possible) is connected between VOUT and ground for output filtering, ensuring output voltage stability and improving load transient response.

[0045] Enable Control: The enable pin 3 (EN) of the U905 is used to control its switching. This pin is connected via an eighth resistor R8 (e.g., 100kΩ, possibly as a pull-up or voltage divider with R9) and a ninth resistor R9 (e.g., 10kΩ). The other end of R9 is connected to a GPIO pin of the CPU (e.g., U1CTS / GPIO18 shown in the diagram; the specific pin can be configured by software). When the CPU outputs a high level through this GPIO (or makes the EN pin active high), the U905 turns on and outputs 3.3V; when the CPU outputs a low level (or makes the EN pin low), the U905 turns off, thereby cutting off power to subsequent circuits (especially the RF unit) to achieve energy saving.

[0046] Grounding: Pin 2 (GND) of U905 is grounded.

[0047] Reset unit (refer to) Figure 4 ): This unit is used to perform a hardware reset of the RF chip U909 under the control of the CPU to deal with possible deadlock or initialization requirements.

[0048] The core switching element is the third N-type field-effect transistor Q3 (such as a small-signal MOSFET like the 2N7002). The source (S) of Q3 is directly grounded. The drain (D) of Q3 is connected to the reset pin 8 (RESET) of the RF chip U909.

[0049] The twelfth resistor R12 (e.g., 10kΩ) is connected at one end to the 3.3V operating power supply and at the other end to the drain of Q3 (i.e., the RESET pin of U909). The function of R12 is to pull the RESET pin high when Q3 is off, so that U909 is in normal operating condition.

[0050] The gate (G) of Q3 is connected to a GPIO pin of the CPU (e.g., U1CTS / GPIO18 in the diagram) via a tenth resistor R10 (e.g., 10kΩ, for current limiting and protection). If multiplexing with the power enable, pay attention to the logic; it is generally recommended to use a separate GPIO. The eleventh resistor R11 (e.g., 100kΩ) is connected between the gate of Q3 and ground as a pull-down resistor to ensure that the gate of Q3 is low and Q3 remains off when the CPU's GPIO is not initialized or in a high-impedance state.

[0051] Operating Logic: When the CPU needs to reset U909, it controls the GPIO to output a high level to the gate of Q3. This turns on Q3, forcibly pulling its drain to a low level close to ground, thereby pulling the RESET pin of U909 low and triggering the reset operation of U909. After the reset is complete, the CPU restores the GPIO output to a low level, Q3 turns off, and the RESET pin returns to a high level under the pull-up action of R12, and U909 begins normal operation.

[0052] Level conversion unit (reference) Figure 3 ): Because the UART interface level of the RF chip U909 is typically 3.3V logic, while the UART interface level of the CPU (such as some GPIOs of the UIS8910) may be 1.8V logic, level conversion is required to ensure reliable communication. (See attached image) Figure 3 A bidirectional or two unidirectional level shifting circuit implemented using N-type MOSFETs is demonstrated.

[0053] The first channel (CPU 1.8V -> U909 3.3V): The CPU's serial port transmit pin (U2RXD / GPIO20, output 1.8V logic) is connected to the source (S) of the first N-type field-effect transistor Q1. The gate (G) of Q1 is pulled up to the 3.3V power supply through the third resistor R3 (e.g., 4.7kΩ). The drain (D) of Q1 is pulled up to the 3.3V power supply through the fifth resistor R5 (e.g., 10kΩ) and connected to the serial port receive pin 3 (UART_TX) of U909. The second resistor R2 (e.g., 10kΩ) pulls up the source of Q1 to the 1.8V power supply.

[0054] Operating principle (simplified explanation: unidirectional): When the CPU sends logic '0' (close to 0V), the source of Q1 is very low, Vgs (gate-source voltage) is about 3.3V, which is much greater than the turn-on threshold voltage Vth of Q1. Q1 turns on, and its drain is pulled low to close to 0V. U909 receives logic '0'. When the CPU sends logic '1' (close to 1.8V), the source of Q1 is 1.8V, and Vgs is about 1.5V. If this value is still greater than Vth, Q1 turns on, and its drain is also pulled to close to 1.8V. However, because R5 pulls up to 3.3V, the actual output may not be ideal or may depend on the precise threshold. A more standard 1.8V to 3.3V unidirectional conversion would use a BJT or a dedicated IC. If this circuit is understood as a MOSFET level conversion method for bidirectional buses (such as I2C), it depends on the symmetry of the MOSFET and the characteristics of the body diode.

[0055] The second channel (U909 3.3V -> CPU 1.8V): The serial transmit pin 4 of U909 (UART_RX, output 3.3V logic) is connected to the drain (D) of the second N-type MOSFET Q2. The gate (G) of Q2 is pulled up to the 1.8V power supply through the seventh resistor R7 (e.g., 4.7kΩ). The source (S) of Q2 is pulled up to the 1.8V power supply through the sixth resistor R6 (e.g., 10kΩ) and connected to the CPU's serial receive pin (U2TXD / GPIO21). The fourth resistor R4 (e.g., 10kΩ) pulls up the drain of Q2 to the 3.3V power supply.

[0056] Operating principle (simplified as unidirectional): When U909 sends logic '0' (close to 0V), the drain of Q2 is low. If the gate of Q2 is 1.8V, then Vgd (gate-drain voltage) is positive, which may cause Q2 to partially conduct or affect the body diode. When U909 sends logic '1' (3.3V), the drain of Q2 is 3.3V, and Vgs (gate-source voltage, the source is pulled up to 1.8V by R6) is approximately 0V or negative (depending on the precise state of Q2). Q2 is off, and the CPU senses the 1.8V logic '1' through R6. The simplest way to perform a unidirectional conversion from 3.3V to 1.8V is to use a resistor divider, or a 1.8V buffer with an input withstand voltage of 3.3V.

[0057] Important Note: Attached Figure 3 The MOSFET level shifting circuit shown was originally designed for level shifting on bidirectional open-drain buses such as I2C. While it can work under certain conditions for unidirectional UART signals, the logic is not the most direct or optimal. To ensure absolute clarity and reliability, it is strongly recommended to use a standard unidirectional level shifting scheme in actual product design and new patent applications, such as: For 1.8V->3.3V: Use an NPN transistor or a 3.3V buffer that is active low on input.

[0058] For 3.3V to 1.8V: Use a simple resistor divider network, or a 1.8V buffer that is active high at input (make sure its input pin can withstand 3.3V).

[0059] Alternatively, use dedicated multi-channel level conversion ICs, such as the TXS010x series or TXB010x series, which integrate more sophisticated logic.

[0060] During work: Power-on and initialization: When the broadcaster is powered on, the power supply unit U905 starts working under the control of the CPU's GPIO (or by default power-on enable), outputting a stable 3.3V power supply to all parts of the system.

[0061] The CPU executes an initialization program, which includes setting the functions of its GPIO ports (used to control power enable, reset, UART communication, etc.).

[0062] The CPU performs a hardware reset on the RF chip U909 through the reset unit (Q3 circuit) to ensure that U909 is in a known initial state.

[0063] The CPU sends configuration commands to the U909 via the UART interface (if needed), such as setting the working channel and receiving mode.

[0064] The CPU puts the U909 into wireless signal receiving mode, waiting to receive a unique location identifier code from the site transmitter.

[0065] Attraction location identification: When a tourist carries a radio into a scenic area with a pre-set radio frequency transmitter (for example, the east entrance of the Long Corridor in the Summer Palace), the radio's 2.4G ceramic antenna L908 will receive the radio frequency signal broadcast by the transmitter in that area.

[0066] The radio frequency chip U909 demodulates the signal and extracts the unique location identifier contained therein (e.g., a string "YHY_CL_EAST_001").

[0067] The U909 sends this identifier code to the CPU's UART receive pin (U2TXD / GPIO21) via its UART_RX pin (pin 4) through the level conversion unit (second channel).

[0068] Information matching and decision-making: The CPU receives the complete and unique location identifier "YHY_CL_EAST_001" in its UART receive interrupt service routine or main loop polling.

[0069] The CPU uses this identifier as a key to search within its internal storage unit's pre-stored "attraction data table". Example of the data table structure: |Unique Location Identifier|Attraction Name|Audio File Name||---------------------|-----------|-----------------------||"YHY_CL_EAST_001"|"East Entrance of the Long Corridor in the Summer Palace"|"audio / changlang_east.mp3"||"YHY_FX_GE_TOP_001"|"Top of the Tower of Buddhist Incense"|"audio / foxiangge_top.mp3"||...|...|...| The CPU compares the received code with the "Unique Location Identifier" field in the table one by one.

[0070] Tourist attraction information broadcast: Match successful: If the CPU finds a record in the data table that exactly matches "YHY_CL_EAST_001", it determines that the current tourist is located at "East Entrance of the Long Corridor of the Summer Palace". The CPU extracts the corresponding "attraction name" ("East Entrance of the Long Corridor of the Summer Palace") and "audio file name" ("audio / changlang_east.mp3") from the record.

[0071] The CPU then controls the audio playback component (for example, by sending a digital audio stream to the audio CODEC via the I2S interface, or by outputting an analog audio signal to the audio amplifier via PWM) to load and play the audio file named "audio / changlang_east.mp3".

[0072] Visitors can hear a detailed introduction about the "East Entrance of the Long Corridor in the Summer Palace".

[0073] (Optional) If the broadcasting machine has a display screen, the CPU can simultaneously send the name of the attraction, "East Entrance of the Long Corridor of the Summer Palace," to the display screen.

[0074] Matching failure: If the CPU does not find a matching identifier in the data table (possibly because the tourist is in a signal dead zone, signal interference, or receives a code from an unknown transmitter), the CPU will not perform the broadcast operation, or will play a prompt tone (such as "Current location not identified").

[0075] Status updates and continuous operation: The CPU can be designed to temporarily ignore repeated reception of the same location identifier code after a successful broadcast (to avoid repeated broadcasts at the same location) until a new, different location identifier code is received, or after a preset period of time, before lifting the ignore.

[0076] The system is constantly receiving information. When tourists move to the next attraction with a transmitter, the above process will repeat, achieving automatic and continuous explanation of the attractions.

[0077] The CPU can alert the user when the battery is low by monitoring battery voltage and other methods. When there is no operation for an extended period or no valid position signal, the CPU can control the power supply unit to shut down components such as the radio frequency module, entering a low-power standby mode.

[0078] Finally, it should be noted that any cross-referencing or superposition of the various embodiments of this solution by those skilled in the art still falls within the original disclosure scope of this solution. Furthermore, the above descriptions are merely preferred embodiments of this utility model and are not intended to limit this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A radio frequency positioning-based audio guide system for tourist attractions, characterized in that, include: The radio frequency unit is configured to receive a unique location identifier code representing the location of a scenic spot, which is sent by a radio frequency transmitter preset at the scenic spot. A central processing unit (CPU), electrically connected to the radio frequency unit, is used to process the unique location identifier code; A storage unit is electrically connected to the central processing unit (CPU). The storage unit pre-stores a scenic spot data table, which contains the scenic spot name and scenic spot description information corresponding to the unique location identifier. The power supply unit is electrically connected to the radio frequency unit and the central processing unit (CPU) to provide operating power to the radio frequency unit and the central processing unit (CPU); A reset unit, electrically connected to the radio frequency unit and the central processing unit (CPU), is used to reset the radio frequency unit according to the instructions of the central processing unit (CPU). A level conversion unit is disposed between the radio frequency unit and the central processing unit (CPU) for level conversion of the generated serial communication signals.

2. The radio frequency positioning-based scenic spot explanation system according to claim 1, characterized in that, The radio frequency unit includes: Radio frequency chip (U909); The first capacitor (C1) and the second capacitor (C2) are connected in parallel between the power supply pin (9) of the RF chip (U909) and ground for power supply filtering. 2.4G ceramic antenna (L908); and The antenna matching network, consisting of a third capacitor (C3) and a first resistor (R1) connected in series or in parallel, is connected between the antenna pin (22) of the RF chip (U909) and the input pin (1) of the 2.4G ceramic antenna (L908).

3. The radio frequency positioning-based scenic spot explanation system according to claim 1, characterized in that, The power supply unit includes: The voltage regulator chip (U905) has an input pin (1) that receives the main power supply of the system and an output pin (5) that outputs a stable operating voltage to the radio frequency unit and the central processing unit (CPU). The fifth capacitor (C5) is connected between the input pin (1) of the voltage regulator chip (U905) and ground for input filtering; The sixth capacitor (C6) is connected between the output pin (5) of the voltage regulator chip (U905) and ground for output filtering; The enable control circuit includes an eighth resistor (R8) and a ninth resistor (R9). One end of the ninth resistor (R9) is connected to the GPIO pin of the central processing unit (CPU), and the other end, together with the eighth resistor (R8), is connected to the enable pin (3) of the voltage regulator chip (U905). This allows the central processing unit (CPU) to control the start and stop of the voltage regulator chip (U905) through the GPIO pin.

4. The radio frequency positioning-based scenic spot explanation system according to claim 1, characterized in that, The reset unit includes: The third N-type field-effect transistor (Q3) has its source grounded and its drain connected to the reset pin (8) of the RF chip (U909) in the RF unit. The twelfth resistor (R12) is connected at one end to the operating power supply and at the other end to the drain of the third N-type field-effect transistor (Q3) to pull up the reset pin (8). The gate control circuit includes a tenth resistor (R10) and an eleventh resistor (R11). One end of the tenth resistor (R10) is connected to the GPIO pin of the central processing unit (CPU), and the other end, together with the common terminal of the eleventh resistor (R11), is connected to the gate of the third N-type field-effect transistor (Q3). The other end of the eleventh resistor (R11) is grounded. The CPU controls the conduction and cutoff of the third N-type field-effect transistor (Q3) through the GPIO pin, thereby controlling the reset of the RF chip (U909).

5. The radio frequency positioning-based scenic spot explanation system according to claim 1, characterized in that, The level conversion unit includes: The first level conversion channel is used to convert the low-level serial port signal output by the central processing unit (CPU) into the high-level serial port signal required by the radio frequency unit. The first level conversion channel includes a first N-type field-effect transistor (Q1), whose source is connected to the serial port transmit pin of the central processing unit (CPU), whose drain is connected to the serial port receive pin of the radio frequency chip (U909) in the radio frequency unit, and is configured as a pull-up and gate drive by a second resistor (R2), a third resistor (R3) and a fifth resistor (R5). The second level conversion channel is used to convert the high-level serial port signal output by the RF chip (U909) in the RF unit into the low-level serial port signal required by the central processing unit (CPU). The second level conversion channel includes a second N-type field-effect transistor (Q2), whose drain is connected to the serial port transmit pin of the RF chip (U909), whose source is connected to the serial port receive pin of the central processing unit (CPU), and is configured as a pull-up and gate drive by a fourth resistor (R4), a sixth resistor (R6), and a seventh resistor (R7).

6. The radio frequency positioning-based scenic spot explanation system according to claim 1, characterized in that, The central processing unit (CPU) is further configured to: obtain a received unique location identifier from the radio frequency unit; match the obtained unique location identifier with a unique location identifier in a pre-stored attraction data table in the storage unit; if the match is successful, extract the attraction name and attraction description information corresponding to the unique location identifier from the attraction data table; and control the audio playback component to play the attraction description information.

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