Road icing prediction and warning device

Abstract

The application relates to a road icing prediction and early warning device, which belongs to the field of road traffic safety monitoring equipment and is used for providing more stable road icing signal transmission capacity. The road icing prediction and early warning device comprises a sensor assembly, a signal processing unit, a remote signal transmission module and a solar power supply module. The sensor assembly is arranged on a road and is used for detecting whether the road surface is iced and sending a signal. The signal processing unit is in communication connection with the sensor assembly and is used for receiving the signal of the sensor assembly and pre-processing the signal. The remote signal transmission module is in communication connection with the signal output end of the signal processing unit and is used for receiving and transmitting the signal of the signal processing unit. The remote signal transmission module comprises a parallel NB-IoT module and a GPRS module. The solar power supply module comprises a solar cell panel, a charging management circuit, a storage battery and a power management circuit, and the solar cell panel is electrically connected with the remote signal transmission module.

Description

Technical Field

[0001] This application relates to the field of road traffic safety monitoring equipment, and in particular to a road icing forecast and early warning device. Background Technology

[0002] In cold weather, road icing is frequent, seriously threatening transportation safety and easily causing traffic accidents, resulting in significant casualties and property damage. Therefore, icing detection sensors are installed on roads and airport runways to monitor road icing conditions and transmit information in real time, facilitating the issuance of early warning signals for ice breakage on airport runways and road icing.

[0003] However, icing detection sensors are also scattered on the road surface in outdoor areas far from the signal station. However, the distance between the sensors and the base station is far, the signal transmission stability is poor, and the wiring method is troublesome. Utility Model Content

[0004] This application provides a road icing forecast and early warning device for providing more stable road icing signal transmission capability.

[0005] This application provides a road icing forecast and early warning device, including a sensor assembly, a signal processing unit, a remote signal transmission module, and a solar power supply module. The sensor assembly is installed on the road and is used to detect whether the road surface is icy and emit a signal. The signal processing unit is communicatively connected to the sensor assembly and is used to receive the signal from the sensor assembly and preprocess the signal. The remote signal transmission module is communicatively connected to the signal output terminal of the signal processing unit and is used to receive and transmit the signal from the signal processing unit. The remote signal transmission module includes a parallel NB-IoT module and a GPRS module. The solar power supply module includes a solar panel, a charging management circuit, a battery, and a power management circuit. The solar panel is electrically connected to the remote signal transmission module and is able to supply power to the remote signal transmission module.

[0006] The remote signal transmission module in this application adopts a combination of wireless NB-IoT and GPRS communication methods, giving full play to the advantages of the two communication technologies. NB-IoT meets the needs of periodic transmission with low power consumption and small data volume, while GPRS enables real-time and rapid transmission of large amounts of data. Combined with dedicated data transmission protocols and security encryption measures, it ensures the stability, accuracy and security of data transmission in different environments, providing strong support for traffic management departments to grasp the road icing situation in a timely manner.

[0007] Solar power modules utilize clean energy and achieve sustainable power supply through high-efficiency solar panels, sophisticated charging management circuits, and large-capacity lithium polymer batteries, freeing the device from dependence on the traditional power grid. They are particularly suitable for remote areas, mountainous regions, and other areas with inconvenient power supply, reducing equipment installation and maintenance costs and improving the device's applicability and flexibility.

[0008] In some embodiments of this application, the NB-IoT module is a BC28 module, and the GPRS module is a SIM800C module. The BC28 module supports NB-IoT / eMTC / GSM multi-mode communication and operates in frequency bands covering mainstream global frequency bands. The SIM800C module supports GSM / GPRS networks and has a high data transmission rate. The combination of the two can achieve stable, remote, and secure signal transmission.

[0009] In some embodiments of this application, the signals transmitted by the remote signal transmission module are encrypted using the AES algorithm. By encrypting and authenticating communication signals, the accuracy, reliability, and security of data transmission are ensured.

[0010] In some embodiments of this application, the road icing forecast and early warning device further includes a housing, which is disposed outside the sensor assembly, with a remote signal transmission module disposed inside the housing, and a charging management circuit, a battery, and a power management circuit disposed inside the housing. The housing can protect the components located therein.

[0011] In some embodiments of this application, the outer casing is provided with ventilation holes and heat sinks, with the heat sinks disposed at the ventilation holes. The ventilation holes and heat sinks ensure normal heat dissipation of the device.

[0012] In some embodiments of this application, the remote signal transmission module and the signal processing unit are connected via a communication line, and the housing is provided with a communication interface for plugging in the communication line. The communication line enables fast and stable signal transmission between the remote signal transmission module and the signal processing unit.

[0013] In some embodiments of this application, a power supply line is further provided between the solar power module and the signal processing unit. The power supply line is used to enable the solar power module to supply power to the sensor components and the signal processing unit, and the outer casing is provided with a power supply interface for plugging in the power supply line. The power supply line enables the solar power module to stably supply power to the sensor components and the signal processing unit.

[0014] In some embodiments of this application, the sensor assembly includes a temperature sensor, a humidity sensor, and an ultrasonic ice thickness sensor. By combining the temperature sensor, humidity sensor, and ultrasonic ice thickness sensor with signal processing circuitry and data processing algorithms, road icing-related data can be accurately and in real-time collected and analyzed, improving the accuracy and reliability of icing warnings and effectively reducing the risk of traffic accidents caused by road icing.

[0015] In some embodiments of this application, the signal processing unit includes a signal amplification circuit, a filtering circuit, and an analog-to-digital conversion circuit. The signal processing unit can preprocess the sensor signal to facilitate stable signal transmission and encryption. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the technical solution of this utility model and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solution of this utility model and do not constitute a limitation on the technical solution of this utility model.

[0017] Figure 1 This is a schematic block diagram illustrating the connection of a road icing forecast and early warning device provided in an embodiment of this application.

[0018] Reference numerals: 1-Sensor assembly; 11-Temperature sensor; 12-Humidity sensor; 13-Ultrasonic ice thickness sensor; 2-Signal processing unit; 21-Signal amplification circuit; 22-Filtering circuit; 23-Analog-to-digital conversion circuit; 3-Remote signal transmission module; 31-NB-IoT module; 32-GPRS module; 4-Solar power supply module; 41-Solar panel; 42-Battery; 43-Charging management circuit; 44-Power management circuit; 5-Housing; 6-Power supply line. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0021] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this application have the meaning of establishing electrical connection. The specific meaning needs to be understood in conjunction with the context.

[0023] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0024] In cold weather, road icing is frequent, seriously threatening transportation safety and easily causing traffic accidents, resulting in significant casualties and property damage. Therefore, icing detection sensors are installed on roads and airport runways to monitor road icing conditions and transmit information in real time, facilitating the issuance of early warning signals for ice breakage on airport runways and road icing.

[0025] However, icing detection sensors are also scattered on the road surface in outdoor areas far from the signal station. However, the distance between the sensors and the base station is far, the signal transmission stability is poor, and the wiring method is troublesome.

[0026] Therefore, please refer to Figure 1 This application provides a road icing forecast and early warning device, including a sensor assembly 1, a signal processing unit 2, a remote signal transmission module 3, and a solar power supply module 4.

[0027] Please refer to Figure 1 Sensor assembly 1 is installed on the road and is used to detect whether the road surface is icy and send a signal. Sensor assembly 1 may include a high-precision temperature sensor 11, a humidity sensor 12, and an ultrasonic ice thickness sensor 13.

[0028] Please refer to Figure 1The temperature sensor 11 can be a digital temperature sensor DS18B20, which has high accuracy (±0.5℃), strong anti-interference ability, and adopts a single bus interface. It is installed close to the road surface at 5cm below the road surface to accurately measure the road surface temperature.

[0029] Please refer to Figure 1 The humidity sensor 12 can be the HIH-4000-3, which has a fast response speed and good linearity. It is also installed 5cm below the road surface to monitor changes in road surface humidity in real time.

[0030] Please refer to Figure 1 The ultrasonic ice thickness sensor 13 can be HC-SR04, which is installed on a bracket 30cm above the road surface. It calculates the ice thickness by measuring the propagation time of ultrasonic waves in the air. It has a large measurement range and high accuracy.

[0031] Please refer to Figure 1 The signal processing unit 2 is communicatively connected to the sensor assembly 1. The signal processing unit 2 is used to receive signals from the sensor assembly 1 and preprocess the signals. The signal processing unit 2 may include a signal amplification circuit 21, a filtering circuit 22, and an analog-to-digital conversion circuit 23.

[0032] Please refer to Figure 1 The analog signals output by the humidity sensor 12 and the ultrasonic ice thickness sensor 13 are amplified by the operational amplifier LM358, then filtered out by the second-order active low-pass filter to remove high-frequency noise, and finally converted into digital signals by the high-precision analog-to-digital converter ADC0809 for processing by the microcontroller; the digital signal output by the temperature sensor 11 is directly connected to the microcontroller.

[0033] Please refer to Figure 1 The microcontroller can be an STM32F103 series microcontroller, which processes and analyzes the collected data through preset algorithms to realize the judgment and early warning of road icing conditions.

[0034] Please refer to Figure 1 Sensor assembly 1 and signal processing unit 2 can together form an icing signal processing unit to determine whether the road is icy and the thickness of the ice layer based on the sensor signals.

[0035] Please refer to Figure 1 The remote signal transmission module 3 is communicatively connected to the signal output terminal of the signal processing unit 2. The remote signal transmission module 3 is used to receive and transmit signals from the signal processing unit. The remote signal transmission module 3 includes a parallel NB-IoT module 31 and a GPRS module 32.

[0036] Please refer to Figure 1The remote signal transmission module 3 adopts a communication method that combines NB-IoT and GPRS.

[0037] Please refer to Figure 1 The NB-IoT module 31 can be a BC28 module, which supports NB-IoT / eMTC / GSM multi-mode communication, and its operating frequency band covers the mainstream frequency bands in the world. It is connected to the microcontroller through the UART interface and is used to periodically transmit device status information, low-frequency icing data, etc., to reduce device energy consumption.

[0038] Please refer to Figure 1 The GPRS module 32 can be a SIM800C module, which supports GSM / GPRS networks and has a data transmission rate of up to 85.6Kbps. It is also connected to the microcontroller through a UART interface. When a change in road icing is detected or a query command is received from the monitoring center, it is used to transmit a large amount of icing monitoring data, sensor status and other information to the monitoring center in real time.

[0039] Meanwhile, the module has established a dedicated data transmission protocol. The data frame consists of a frame header, device identifier, data content, a checksum using CRC verification, and a frame trailer. It also defines the communication instruction set between the monitoring center and the monitoring device, and uses the AES algorithm to encrypt the data and authenticate the communication module to ensure the accuracy, reliability, and security of data transmission.

[0040] Please refer to Figure 1 The solar power module 4 includes a solar panel 41, a charging management circuit 43, a battery 42, and a power management circuit 44. The solar panel 41 is electrically connected to the remote signal transmission module 3 and can supply power to the remote signal transmission module 3.

[0041] Please refer to Figure 1 The solar panel 41 can be a 20W monocrystalline silicon solar panel 41, which has high conversion efficiency (up to 20% or more), good stability and long service life, and is used to convert solar energy into electrical energy.

[0042] Please refer to Figure 1 The charging management circuit 43 can use a dedicated charging management chip TP4056, which has functions such as constant current / constant voltage charging mode, overcharge protection, over-discharge protection, and short circuit protection, to achieve safe and efficient charging management of the battery 42.

[0043] Please refer to Figure 1 The storage battery 42 can be a 500Wh lithium polymer battery, configured in a parallel manner, and a protection board is installed on each storage battery 42 to power the device in low light or at night.

[0044] Please refer to Figure 1 The power management circuit 44 uses a DC-DC converter chip LM2596 to convert the electrical energy output from the battery 42 into the corresponding voltage according to the power supply requirements of each component in the device. For example, the voltage of the battery 42 is converted to 3.3V to power the microcontroller STM32F103, and converted to 5V to power the communication modules BC28 and SIM800C.

[0045] Please refer to Figure 1 Meanwhile, the circuit has functions such as power switch control and power monitoring. It controls the power switch through a microcontroller to realize power supply control of each component, reduce power consumption, and uses an ADC to monitor the voltage of the battery 42 in real time. When the power is lower than the set threshold, it sends a low power alarm message to the monitoring center through the remote signal transmission module 3.

[0046] Please refer to Figure 1 The remote signal transmission module 3 in this application adopts a communication method that combines wireless NB-IoT and GPRS, giving full play to the advantages of the two communication technologies. NB-IoT meets the needs of periodic transmission with low power consumption and small data volume, while GPRS enables real-time and rapid transmission of large amounts of data. Combined with dedicated data transmission protocols and security encryption measures, it ensures the stability, accuracy and security of data transmission in different environments, providing strong support for traffic management departments to grasp the road icing situation in a timely manner.

[0047] The solar power module 4 utilizes clean energy and achieves sustainable power supply for the device through a high-efficiency solar panel 41, a sophisticated charging management circuit 43, and a large-capacity lithium polymer battery 42. This eliminates dependence on the traditional power grid and is especially suitable for remote areas, mountainous regions, and other areas with inconvenient power supply. It reduces the installation and maintenance costs of the equipment and improves the applicability and flexibility of the device.

[0048] Please refer to Figure 1 In some examples, the NB-IoT module 31 is a BC28 module, and the GPRS module 32 is a SIM800C module. The BC28 module supports NB-IoT / eMTC / GSM multi-mode communication and operates in frequency bands covering mainstream global frequency bands. The SIM800C module supports GSM / GPRS networks and has a high data transmission rate. Together, they can achieve stable, long-distance, and secure signal transmission.

[0049] In some examples, the signals transmitted by the remote signal transmission module 3 are encrypted using the AES algorithm. Encryption and authentication of communication signals ensure the accuracy, reliability, and security of data transmission.

[0050] In some examples, the AES algorithm is used to encrypt data in the remote signal transmission module 3 of the road icing forecast and early warning device. Its core logic is to use the principle of symmetric encryption to encrypt and decrypt data with a key of a specific length.

[0051] Specifically, the AES algorithm supports various key lengths, including 128-bit, 192-bit, and 256-bit. The longer the key length, the stronger the encryption. In this device, after selecting a suitable key length, the encryption process divides the input plaintext data into fixed block lengths (e.g., 128 bits). Then, under the control of the key, a series of complex operations, such as byte substitution, row shifting, column mixing, and round key addition, convert the plaintext into ciphertext. When the monitoring center receives the ciphertext, it uses the same key to perform the reverse operation, thereby restoring the original plaintext data.

[0052] The AES algorithm plays a crucial role in long-distance signal transmission. On one hand, it effectively prevents data from being illegally intercepted during transmission. For example, if road icing data is not encrypted during transmission from monitoring devices to the monitoring center, malicious actors could obtain detailed road icing information through network sniffing, potentially causing serious disruption to traffic management. With AES encryption, even if the data is intercepted, the thief will only receive a meaningless string of gibberish without the correct key, unable to obtain the actual road icing data. On the other hand, the AES algorithm also prevents data tampering. Because the encryption process is closely related to the key, if the data is altered during transmission, the receiving end will not be able to obtain the correct plaintext during decryption, thus enabling timely detection of data anomalies and ensuring data integrity and authenticity.

[0053] In other examples, other encryption methods may be used, such as the DES or RSA algorithms.

[0054] Please refer to Figure 1 In some examples, the road icing forecast and warning device also includes a housing 5, which is disposed outside the sensor assembly 1, with the remote signal transmission module 3 disposed inside the housing 5, and the charging management circuit 43, battery 42, and power management circuit 44 disposed inside the housing 5. The housing 5 can protect the components located therein.

[0055] In some examples, the outer casing 5 is made of high-strength, waterproof, dustproof and corrosion-resistant engineering plastic material, and the interior adopts a layered design, with the icing signal processing unit, the remote signal transmission module 3 and the solar power supply module 4 installed in different areas to avoid electromagnetic interference between the components.

[0056] In some examples, the signal processing unit 2 can be housed within the housing 5, or it can be protected by a separate housing.

[0057] In some examples, the housing 5 is provided with ventilation holes and heat sinks, with the heat sinks located at the ventilation holes. The ventilation holes and heat sinks ensure proper heat dissipation of the device.

[0058] Please refer to Figure 1 In some examples, the remote signal transmission module 3 and the signal processing unit 2 are connected via a communication line, and the housing 5 is provided with a communication interface for plugging in the communication line. The communication line enables fast and stable signal transmission between the remote signal transmission module 3 and the signal processing unit 2.

[0059] For example, the communication line can be a coaxial cable or other signal cable used for communication, and the communication interface can be an RS-232 interface or an RS-485 interface.

[0060] Please refer to Figure 1 In some examples, a power supply line 6 is also provided between the solar power module 4 and the signal processing unit 2. The power supply line 6 is used to enable the solar power module 4 to supply power to the sensor assembly 1 and the signal processing unit 2. The housing 5 is provided with a power supply interface for plugging in the power supply line 6. The power supply line 6 enables the solar power module 4 to stably supply power to the sensor assembly 1 and the signal processing unit 2.

[0061] In some examples, the power supply line 6 can be a copper core PVC insulated wire or a rubber insulated wire, both of which can provide good stability for outdoor use.

[0062] For example, communication lines and power lines can be twisted together to facilitate wiring.

[0063] Please refer to Figure 1 In some examples, sensor component 1 includes a temperature sensor 11, a humidity sensor 12, and an ultrasonic ice thickness sensor 13. By combining the temperature sensor 11, humidity sensor 12, and ultrasonic ice thickness sensor 13 with signal processing circuitry and data processing algorithms, road icing-related data can be accurately and in real-time collected and analyzed, improving the accuracy and reliability of icing warnings and effectively reducing the risk of traffic accidents caused by road icing.

[0064] Please refer to Figure 1 In some examples, the signal processing unit 2 includes a signal amplification circuit 21, a filtering circuit 22, and an analog-to-digital conversion circuit 23. The signal processing unit 2 can preprocess the sensor signal to facilitate stable signal transmission and encryption.

[0065] Specifically, this example can be used when it is necessary to install this road icing forecast and early warning device outdoors.

[0066] First, according to the sensor installation requirements, the temperature sensor 11 and humidity sensor 12 are installed tightly against each other 5cm below the road surface. The ultrasonic ice thickness sensor 13 is installed on a bracket 30cm vertically above the road surface. The sensor connection wires are then led into the device housing 5 through the pre-drilled sensor mounting holes and correctly connected to the signal processing unit 2 of the icing signal processing unit. Next, the solar panel 41 is installed on top of or around the device housing 5 in a well-lit location to ensure it receives sufficient sunlight. The solar panel 41 is then connected to the charging management circuit 43 of the solar power module 4 via wires. Finally, the communication antennas of the NB-IoT module 31 and GPRS module 32 are installed in suitable locations through the pre-drilled communication antenna interfaces to ensure good signal reception and transmission. The communication modules are then connected to the microcontroller of the remote signal transmission module 3 via the UART interface.

[0067] After the device is started, temperature sensor 11, humidity sensor 12, and ultrasonic ice thickness sensor 13 begin to collect real-time data on road surface temperature, humidity, and ice thickness. The analog signals output by humidity sensor 12 and ultrasonic ice thickness sensor 13 are amplified by signal amplification circuit 21, filtered by filtering circuit 22, and then converted into digital signals by analog-to-digital converter circuit 23. These digital signals, along with the digital signal output by temperature sensor 11, are transmitted to the microcontroller. The microcontroller processes and analyzes the collected data according to a preset data analysis algorithm. When it determines that the road is icy or has reached a warning threshold, it generates corresponding warning information.

[0068] For low-frequency, small-volume device status information and icing data, the NB-IoT module 31 encapsulates and encrypts the data according to the established data transmission protocol and transmits it to the monitoring center periodically. When a change in road icing is detected or a query command is received from the monitoring center, the microcontroller controls the GPRS module 32 to package and encrypt a large amount of detailed icing data, sensor status and other information, and transmits it to the monitoring center quickly through the GPRS network.

[0069] Solar panel 41 converts solar energy into electrical energy under sunlight, which is then processed by charging management circuit 43 to charge battery 42. The electrical energy stored in battery 42 is converted into the voltage required by various components of the device by power management circuit 44 to power the device. Power management circuit 44 monitors the battery level of battery 42 in real time. When the battery level is lower than a set threshold, it controls remote signal transmission module 3 via microcontroller to send a low battery alarm message to the monitoring center, reminding maintenance personnel to handle the situation promptly.

[0070] After receiving the data and early warning information transmitted by the device, the monitoring center analyzes and processes the data and takes timely measures, such as issuing road icing warnings and arranging de-icing operations, to ensure road traffic safety.

[0071] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0072] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A road icing forecast and early warning device, characterized in that, include: A sensor assembly, installed on the road, is used to detect whether the road surface is icy and to send a signal. A signal processing unit is communicatively connected to the sensor assembly, and the signal processing unit is used to receive signals from the sensor assembly and preprocess the signals. A remote signal transmission module is communicatively connected to the signal output terminal of the signal processing unit. The remote signal transmission module is used to receive and transmit signals from the signal processing unit. The remote signal transmission module includes a parallel NB-IoT module and a GPRS module. The solar power supply module includes a solar panel, a charging management circuit, a battery, and a power management circuit. The solar panel is electrically connected to the remote signal transmission module and can supply power to the remote signal transmission module.

2. The road icing forecast and early warning device according to claim 1, characterized in that, The NB-IoT module is a BC28 module, and the GPRS module is a SIM800C module.

3. The road icing forecast and early warning device according to claim 2, characterized in that, The remote signal transmission module uses the AES algorithm to encrypt the transmitted signals.

4. The road icing forecast and early warning device according to any one of claims 1 to 3, characterized in that, The road icing forecast and early warning device also includes a housing, which is disposed outside the sensor assembly, and the remote signal transmission module is disposed inside the housing. The charging management circuit, the battery, and the power management circuit are disposed inside the housing.

5. The road icing forecast and early warning device according to claim 4, characterized in that, The outer casing is provided with ventilation holes and heat sinks, with the heat sinks located at the ventilation holes.

6. The road icing forecast and early warning device according to claim 5, characterized in that, The remote signal transmission module and the signal processing unit are connected via a communication line, and the outer casing is provided with a communication interface for plugging in the communication line.

7. The road icing forecast and early warning device according to claim 6, characterized in that, A power supply line is also provided between the solar power supply module and the signal processing unit. The power supply line is used to enable the solar power supply module to supply power to the sensor assembly and the signal processing unit. The housing is provided with a power supply interface for plugging in the power supply line.

8. The road icing forecast and early warning device according to claim 1, characterized in that, The sensor assembly includes a temperature sensor, a humidity sensor, and an ultrasonic ice thickness sensor.

9. The road icing forecast and early warning device according to claim 1, characterized in that, The signal processing unit includes a signal amplification circuit, a filtering circuit, and an analog-to-digital conversion circuit.

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