Circuit for calculating saturation and parking times of intersection

Abstract

The utility model discloses a circuit for calculating saturation and parking times of an intersection, and belongs to the technical field of electronic circuits, the circuit for calculating saturation and parking times of the intersection comprises a vehicle detector interface circuit, a signal lamp color sampling circuit and a data processing and resolving circuit, and additionally or optionally, the signal lamp color sampling circuit is connected with the data processing and resolving circuit. The system further comprises a data encryption and decryption circuit, an Ethernet serial port server and a router. The vehicle detector interface circuit is used for receiving real-time vehicle speed, passing vehicle number and queuing length from a vehicle detector, the signal lamp color sampling circuit is used for sampling on-off states of three colors of traffic signal lamps, and the data processing and resolving circuit is used for processing and resolving received data. Therefore, the intersection saturation and the vehicle parking frequency are generated. The circuit can be directly and electrically connected with a vehicle detector and a traffic signal lamp, and real-time, accurate and automatic calculation of the saturation degree of the intersection and the number of parking times is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic circuits, and more particularly to a circuit for calculating intersection saturation and stopping times. BACKGROUND

[0002] An intersection is a convergence point of pedestrian flow, non-motor vehicle flow and motor vehicle flow, and is the throat of a city road network. The convergence and interweaving of two roads interfere with each other, which reduces the speed of vehicles and easily causes congestion. A traffic signal control system is a comprehensive traffic management system that improves the efficiency and safety of intersection traffic operation through technical means. After the traffic signal control system is operated, the performance of the traffic signal control algorithm used and the effectiveness of the optimization scheme need to be evaluated, so as to improve the operation efficiency and service quality of the system.

[0003] Intersection saturation and stopping times are important indicators for measuring the control efficiency of a traffic signal control algorithm and the passing state of an intersection. In actual applications, radar microwave detectors and video traffic detectors are limited to detecting common intersection traffic parameters such as traffic flow, average speed, lane occupancy rate and queue length. However, the calculation of intersection saturation and stopping times needs to be associated with the color duration of a signal light, and it is difficult to directly detect and obtain the values through a single detector.

[0004] In the prior art, intersection saturation and stopping times are not associated with signal light colors, but are calculated by regularly (usually for more than 15 minutes) counting the average value of traffic flow and vehicle speed. If the statistical period is short, the average value will be greatly different from the actual value due to the influence of the percentage of the green light duration in the statistical period. If the statistical period is long, it is not real-time and cannot meet the needs of real-time adjustment of traffic signal control. CONTENT OF THE INVENTION

[0005] In order to solve the problem that the prior art cannot meet the needs of real-time adjustment of traffic signal control when calculating intersection saturation and stopping times without associating with signal light colors, the present application provides a circuit for calculating intersection saturation and stopping times. The circuit communicates with a vehicle detector to obtain traffic flow, average speed and queue length in real time, and samples a traffic signal light voltage signal through a signal light color sampling circuit to obtain a real-time light color. Data processing is performed inside the circuit, so as to automatically calculate intersection saturation and stopping times.

[0006] In one embodiment of the present application, a circuit for calculating intersection saturation and stopping number is provided, which comprises a vehicle detector interface circuit, a signal light color sampling circuit and a data processing and solving circuit, wherein the vehicle detector interface circuit is electrically connected with the vehicle detector and the data processing and solving circuit respectively, for receiving real-time vehicle speed, vehicle number and queue length from the vehicle detector, and transmitting the received real-time vehicle speed, vehicle number and queue length to the data processing and solving circuit; the signal light color sampling circuit is electrically connected with the traffic signal light and the data processing and solving circuit respectively, for sampling the on-off state of three colors of the traffic signal light, and outputting the on-off state to the data processing and solving circuit; the data processing and solving circuit is used for receiving real-time vehicle speed, vehicle number and queue length from the vehicle detector interface circuit, and receiving the on-off state of three colors from the signal light color sampling circuit, and processing and solving the received data, thereby generating intersection saturation and vehicle stopping number.

[0007] In the above embodiment, further, the vehicle detector interface circuit comprises a 485 conversion chip U1, a resistor R21, a resistor R22, a resistor R23, a resistor R25, a resistor R29, a resistor R30, a resistor R31, a transient voltage suppression diode D4, a transient voltage suppression diode D5, a GDT ceramic gas discharge tube G1 and a capacitor C8, wherein the 1 pin of the 485 conversion chip U1 is connected with the vehicle detector interface input end RXD1 of the data processing and solving circuit through the resistor R21; the 2 pin of the 485 conversion chip U1 is connected with the 3 pin of the 485 conversion chip U1 through the resistor R25, and the 2 pin of the 485 conversion chip U1 is connected with the vehicle detector interface control end 485DIR of the data processing and solving circuit; the 4 pin of the 485 conversion chip U1 is connected with the vehicle detector interface output end TXD1 of the data processing and solving circuit through the resistor R31; the 5 pin of the 485 conversion chip U1 is connected with GND; the 6 pin of the 485 conversion chip U1 is connected with the power voltage through the resistor R29, and the 6 pin of the 485 conversion chip U1 is connected with GND through the transient voltage suppression diode D5, and the 6 pin of the 485 conversion chip U1 is connected with the 2 pin of the GDT ceramic gas discharge tube G1 through the resistor R30; the 7 pin of the 485 conversion chip U1 is connected with GND through the resistor R22, and the 7 pin of the 485 conversion chip U1 is connected with GND through the transient voltage suppression diode D4, and the 7 pin of the 485 conversion chip U1 is connected with the 1 pin of the GDT ceramic gas discharge tube G1 through the resistor R23; the 8 pin of the 485 conversion chip U1 is connected with GND through the capacitor C8, and the 8 pin of the 485 conversion chip U1 is connected with the power voltage; the 1 pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485A; the 2 pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485B; and the 3 pin of the GDT ceramic gas discharge tube G1 is connected with the ground EARTH.

[0008] In the above embodiment, further, the 485 conversion chip U1 adopts SP3485EN, the transient voltage suppression diode D4 adopts SMBJ10CA, the transient voltage suppression diode D5 adopts SMBJ10CA, the GDT ceramic gas discharge tube G1 adopts 3RL090L-6, and the power supply voltage is 3.3V.

[0009] In the above embodiment, further, the signal lamp color sampling circuit comprises an optocoupler U11, an inverter U10, resistors R83, R84, R85, R89, R94, R129, R130, R138, R139, transient voltage suppression diodes ZD2, ZD7, ZD8, capacitors C26, C27, C28, wherein the 1 pin of the inverter U10 is connected to GND through the capacitor C28, at the same time, the 1 pin of the inverter U10 is connected to the power supply voltage through the resistor R85, at the same time, the 1 pin of the inverter U10 is connected to the 16 pin of the optocoupler U11; the 2 pin of the inverter U10 is connected to the signal lamp color interface input end RED of the data processing and calculation circuit; the 3 pin of the inverter U10 is connected to GND through the capacitor C27, at the same time, the 3 pin of the inverter U10 is connected to the power supply voltage through the resistor R84, at the same time, the 3 pin of the inverter U10 is connected to the 14 pin of the optocoupler U11; the 4 pin of the inverter U10 is connected to the signal lamp color interface input end YEL of the data processing and calculation circuit; the 5 pin of the inverter U10 is connected to GND through the capacitor C26, at the same time, the 5 pin of the inverter U10 is connected to the power supply voltage through the resistor R83, at the same time, the 5 pin of the inverter U10 is connected to the 12 pin of the optocoupler U11; the 6 pin of the inverter U10 is connected to the signal lamp color interface input end GREEN of the data processing and calculation circuit; the 1 pin, 3 pin, 5 pin of the optocoupler U11 are connected to the power zero line N; the 2 pin of the optocoupler U11 is connected to the first anode pin of the TVS diode ZD8; the 4 pin of the optocoupler U11 is connected to the first anode pin of the TVS diode ZD2; the 6 pin of the optocoupler U11 is connected to the first anode pin of the TVS diode ZD7; the 11 pin, 13 pin, 15 pin of the optocoupler U11 are connected to GND; the second anode pin of the TVS diode ZD8 is connected to the first pin of the resistor R130; the second pin of the resistor R130 is connected to the first pin of the resistor R139; the second pin of the resistor R139 is the signal lamp interface R0; the second anode pin of the TVS diode ZD2 is connected to the first pin of the resistor R89; the second pin of the resistor 89 is connected to the first pin of the resistor R94; the second pin of the resistor R94 is the signal lamp interface Y0; the second anode pin of the TVS diode ZD7 is connected to the first pin of the resistor R129; the second pin of the resistor 129 is connected to the first pin of the resistor R138; the second pin of the resistor R138 is the signal lamp interface G0.

[0010] In the above embodiment, further, the optocoupler U11 adopts TLP620-4, the inverter U10 adopts SN74HC14D, the transient voltage suppression diode ZD2 adopts SMBJ120CA, the transient voltage suppression diode ZD7 adopts SMBJ120CA, the transient voltage suppression diode ZD8 adopts SMBJ120CA, and the power voltage is 3.3V.

[0011] In the above embodiment, further, the data processing and calculation circuit comprises a microcontroller U2, an RS232 interface chip U14, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R88, a resistor R89, a resistor R90, a resistor R91, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C41, a capacitor C42, a capacitor C43, a capacitor C44, a capacitor C49, a capacitor C50, a capacitor C51, a capacitor C52, wherein the 5th pin of the microcontroller U2 is connected to GND through the capacitor C2, at the same time, the 5th pin of the microcontroller U2 is connected to the 6th pin of the microcontroller U2 through the resistor R1 and the resistor R2, at the same time, the connection point of the resistor R1 and the resistor R2 is connected to GND through the capacitor C3, at the same time, the connection point of the resistor R1 and the resistor R2 is connected to the 5th pin of the microcontroller U2 through the crystal oscillator Y1; the 7th pin of the microcontroller U2 is connected to GND through the capacitor C1, at the same time, the 7th pin of the microcontroller U2 is connected to the power voltage through the resistor R3; the 60th pin of the microcontroller U2 is connected to GND through the resistor R4; the 13th pin of the microcontroller U2 is connected to the power voltage through the resistor R5; the 1st pin, the 19th pin, the 32nd pin, the 48th pin and the 64th pin of the microcontroller U2 are connected to the power voltage; the 28th pin of the microcontroller U2 is connected to GND through the resistor R6; the 12th pin, the 18th pin, the 31st pin, the 47th pin and the 63rd pin of the microcontroller U2 are connected to GND; the 16th pin TXD2 of the microcontroller U2 is connected to the 10th pin of the RS232 interface chip U14; the 17th pin RXD2 of the microcontroller U2 is connected to the 9th pin of the RS232 interface chip U14; the 29th pin TXD3 of the microcontroller U2 is connected to the 11th pin of the RS232 interface chip U14; the 30th pin RXD3 of the microcontroller U2 is connected to the 12th pin of the RS232 interface chip U14; the 42nd pin of the microcontroller U2 is connected to the input end TXD1 of the vehicle detector interface circuit; the 43rd pin of the microcontroller U2 is connected to the output end RXD1 of the vehicle detector interface circuit; the 44th pin of the microcontroller U2 is connected to the control end 485DIR of the vehicle detector interface circuit; the 24th pin of the microcontroller U2 is connected to the output end RED of the signal lamp color sampling circuit; the 25th pin of the microcontroller U2 is connected to the output end YEL of the signal lamp color sampling circuit; the 37th pin of the microcontroller U2 is connected to the output end GREEN of the signal lamp color sampling circuit; the 1st pin of the RS232 interface chip U14 is connected to the 3rd pin of the RS232 interface chip U14 through the capacitor C41; the 4th pin of the RS232 interface chip U14 is connected to the 5th pin of the RS232 interface chip U14 through the capacitor C42; the 2nd pin of the RS232 interface chip U14 is connected to the power voltage through the capacitor C43; the 6th pin of the RS232 interface chip U14 is connected to GND through the capacitor C44; the 16th pin of the RS232 interface chip U14 is connected to the power voltage; the 15th pin of the RS232 interface chip U14 is connected to GND.

[0012] In the above embodiment, further, the microcontroller U2 adopts STM32F103R8T6, the RS232 interface chip U14 adopts MAX3232, and the power voltage is 3.3V.

[0013] In another embodiment of the present application, the circuit for calculating intersection saturation and parking times of the present application further comprises a data encryption and decryption circuit for encrypting and decrypting communication data, which comprises a data encryption chip U5, a capacitor C12, and a capacitor C13, wherein pin 1 of the data encryption chip U5 is connected to GND; pin 8 of the data encryption chip U5 is connected to the power voltage, and at the same time, pin 8 of the data encryption chip is connected to GND through the capacitor C12, and pin 8 of the data encryption chip is connected to GND through the capacitor C13; pin 54 of the microcontroller U2 is connected to the 6-pin input end SSEL1 of the data encryption chip U5; pin 55 of the microcontroller U2 is connected to the 4-pin input end SCK1 of the data encryption chip U5; pin 56 of the microcontroller U2 is connected to the 2-pin output end MISO1 of the data encryption chip U5; pin 57 of the microcontroller U2 is connected to the 3-pin input end MOSI1 of the data encryption chip U5; and pin 58 of the microcontroller U2 is connected to the 7-pin input end HSC_RST of the data encryption chip U5, wherein the encryption chip U5 adopts HSC32C1-S1V30, and the power voltage is 3.3V.

[0014] In another embodiment of the present application, the circuit for calculating intersection saturation and parking times of the present application further comprises an Ethernet serial server for wired transmission of communication data, wherein pin 14 of the RS232 interface chip U14 is connected to the output end TXDOUT3 of the Ethernet serial server through the resistor R90, and at the same time, pin 14 of the RS232 interface chip U14 is connected to GND through the capacitor C50; pin 13 of the RS232 interface chip U14 is connected to the input end RXDOUT3 of the Ethernet serial server through the resistor R88, and at the same time, pin 13 of the RS232 interface chip U14 is connected to GND through the capacitor C52.

[0015] In another embodiment of the present application, the circuit for calculating intersection saturation and parking times of the present application further comprises a router for wireless transmission of communication data, wherein pin 7 of the RS232 interface chip U14 is connected to the output end TXDOUT2 of the router through the resistor R89, and at the same time, pin 7 of the RS232 interface chip U14 is connected to GND through the capacitor C51; pin 8 of the RS232 interface chip U14 is connected to the input end RXDOUT2 of the router through the resistor R91, and at the same time, pin 8 of the RS232 interface chip U14 is connected to GND through the capacitor C49.

[0016] The beneficial effects of the present application are:

[0017] Through the circuit of the present application, direct electrical connection can be achieved with the vehicle detector and the traffic signal light, thereby realizing real-time and accurate automatic calculation of the intersection saturation and the number of stops, solving the problem that the prior art cannot meet the real-time adjustment of traffic signal control when calculating the intersection saturation and the number of stops without being associated with the signal light color. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 A block schematic diagram of the circuit for calculating intersection saturation and number of stops of the present application;

[0019] Figure 2 A vehicle detector interface circuit in the circuit for calculating intersection saturation and number of stops of the present application;

[0020] Figure 3 A signal light color sampling circuit in the circuit for calculating intersection saturation and number of stops of the present application;

[0021] Figure 4 A data processing and solving circuit in the circuit for calculating intersection saturation and number of stops of the present application;

[0022] Figure 5 A data encryption and decryption circuit in the circuit for calculating intersection saturation and number of stops of the present application. DETAILED DESCRIPTION

[0023] Reference Figure 1 In an embodiment of the present application, a circuit for calculating intersection saturation and number of stops is provided, comprising a vehicle detector interface circuit, a signal light color sampling circuit and a data processing and solving circuit, additionally or optionally, the circuit for calculating intersection saturation and number of stops of the present application further comprises a data encryption and decryption circuit.

[0024] The vehicle detector interface circuit is electrically connected with the vehicle detector and the data processing and solving circuit respectively, for receiving real-time vehicle speed, number of vehicles passing and queue length from the vehicle detector, and transmitting the received real-time vehicle speed, number of vehicles passing and queue length to the data processing and solving circuit. The applicable vehicle detector includes but is not limited to video vehicle detector, microwave radar vehicle detector, geomagnetic vehicle detector, etc. The above types of vehicle detectors use video recognition, microwave radar wave reflection, detection of geomagnetic field magnetic flux change, etc. for vehicle detection, and the detection result data includes but is not limited to vehicle speed, number of vehicles passing and queue length. The vehicle detector is provided with a communication interface for outputting the detection result data.

[0025] The signal lamp color sampling circuit is electrically connected with the traffic signal lamp and the data processing and solving circuit respectively, and is used for sampling the lighting and extinguishing states of three colors of the traffic signal lamp, and outputting the lighting and extinguishing states to the data processing and solving circuit. The signal lamp color sampling circuit is directly connected to the power input end of the traffic signal lamp. The national standard of the traffic signal lamp stipulates that the power input of the signal lamp is AC220V. The signal lamp color sampling circuit is connected in parallel to the power input end of the traffic signal lamp, directly samples the power input voltage value of the traffic signal lamp, and transmits the processed electrical signal to the I / O interface of the data processing and solving circuit through voltage reduction, rectification and isolation processing.

[0026] The data processing and solving circuit is used for receiving real-time vehicle speed, vehicle number and queue length from the vehicle detector interface circuit, and receiving the lighting and extinguishing states of three colors from the signal lamp color sampling circuit, and processing and solving the received data, so as to generate the intersection saturation and the vehicle parking number.

[0027] A method for calculating intersection saturation is proposed in patent application CN116824857A, and a method for calculating parking number is proposed in patent application CN118781812A. The method for calculating intersection saturation and parking number in the present application can refer to the technical solutions described in the two pieces of disclosure.

[0028] In the present application, the intersection saturation calculation principle is that the data processing and solving circuit obtains vehicle speed, vehicle number and signal lamp color in real time. The microcontroller U2 of the data processing and solving circuit establishes a list to record the received vehicle speed and vehicle number in the internal storage space, and synchronously calculates the total green light time and the total yellow light time. The controller U2 of the data processing and solving circuit calculates the average speed of the vehicle according to the vehicle speed in the list, calculates the saturation flow according to the calculated average speed, and finally calculates the saturation degree according to the calculated saturation flow and the recorded vehicle number.

[0029] The parking number calculation principle is that the data processing and solving circuit obtains vehicle speed, vehicle number, queue length and signal lamp color in real time. The controller U2 of the data processing and solving circuit records the queue length data at the moment when the red light ends and the green light lights up in the internal storage space. At the same time, the microcontroller U2 of the data processing and solving circuit establishes a list to record the received vehicle speed and vehicle number in the internal storage space, and synchronously calculates the total green light time and the total yellow light time. The controller U2 of the data processing and solving circuit calculates the average speed of the vehicle according to the vehicle speed in the list, calculates the maximum releasable queue of the lane according to the green light time and the average speed of the vehicle. Finally, the controller U2 of the data processing and solving circuit calculates the parking number of the current green light according to the calculated maximum releasable queue of the lane and the stored queue length at the moment when the red light ends and the green light lights up.

[0030] Referring to Figure 2 In one embodiment of the present application, the vehicle detector interface circuit in the circuit for calculating intersection saturation and number of stops of the present application comprises a 485 conversion chip U1, a resistor R21, a resistor R22, a resistor R23, a resistor R25, a resistor R29, a resistor R30, a resistor R31, a transient voltage suppression diode D4, a transient voltage suppression diode D5, a GDT ceramic gas discharge tube G1, and a capacitor C8, wherein the 1 pin of the 485 conversion chip U1 is connected to the vehicle detector interface input end RXD1 of the data processing and solving circuit through the resistor R21; the 2 pin of the 485 conversion chip U1 is connected to the vehicle detector interface control end 485DIR of the data processing and solving circuit through the resistor R25, and at the same time, the 2 pin of the 485 conversion chip U1 is connected to the 3 pin of the 485 conversion chip U1; the 4 pin of the 485 conversion chip U1 is connected to the vehicle detector interface output end TXD1 of the data processing and solving circuit through the resistor R31; the 5 pin of the 485 conversion chip U1 is connected to GND; the 6 pin of the 485 conversion chip U1 is connected to the power supply voltage through the resistor R29, and at the same time, the 6 pin of the 485 conversion chip U1 is connected to GND through the transient voltage suppression diode D5, and at the same time, the 6 pin of the 485 conversion chip U1 is connected to the 2 pin of the GDT ceramic gas discharge tube G1 through the resistor R30; the 7 pin of the 485 conversion chip U1 is connected to GND through the resistor R22, and at the same time, the 7 pin of the 485 conversion chip U1 is connected to GND through the transient voltage suppression diode D4, and at the same time, the 7 pin of the 485 conversion chip U1 is connected to the 1 pin of the GDT ceramic gas discharge tube G1 through the resistor R23; the 8 pin of the 485 conversion chip U1 is connected to GND through the capacitor C8, and at the same time, the 8 pin of the 485 conversion chip U1 is connected to the power supply voltage; the 1 pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485A; the 2 pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485B; and the 3 pin of the GDT ceramic gas discharge tube G1 is connected to the ground EARTH.

[0031] Chip U1 is a communication interface voltage conversion chip, which converts the 485 level of the vehicle detector communication interface into the TTL level of the data processing and calculation circuit communication interface; resistor R21 is a series resistor of the U1 data receiving pin; resistor R22 is a pull-down resistor of the U1 differential data pin B; resistor R23 is a series resistor of the U1 differential data pin B; resistor R25 is an input resistor of the U1 data direction control pin; resistor R29 is a pull-up resistor of the U1 differential data pin A; resistor R30 is a series resistor of the U1 differential data pin A; resistor R31 is a series resistor of the U1 data output pin; transient voltage suppression diode D4 is a surge current discharge TVS tube of the U1 differential data pin B to GND; transient voltage suppression diode D5 is a surge current discharge TVS tube of the U1 differential data pin A to GND; GDT ceramic gas discharge tube G1 is a surge current discharge TVS tube of the U1 differential data pins A and B to the ground. Capacitor C8 is a power supply filtering capacitor of U1.

[0032] In an embodiment of the present application, the 485 conversion chip U1 adopts SP3485EN, resistor R21 is 120 ohms, resistor R22 is 4.3k ohms, resistor R23 is 10 ohms, resistor R25 is 33 ohms, resistor R29 is 4.3k ohms, resistor R30 is 10 ohms, resistor R31 is 33 ohms, transient voltage suppression diode D4 adopts SMBJ10CA, transient voltage suppression diode D5 adopts SMBJ10CA, GDT ceramic gas discharge tube G1 adopts 3RL090L-6, and capacitor C8 is 0.1uf.

[0033] Referring to Figure 3In an embodiment of the present application, the signal light color sampling circuit in the circuit for calculating intersection saturation and stopping times of the present application comprises optocoupler U11, inverter U10, resistor R83, resistor R84, resistor R85, resistor R89, resistor R94, resistor R129, resistor R130, resistor R138, resistor R139, transient voltage suppression diode ZD2, ZD7, ZD8, capacitor C26, C27, C28, wherein the 1 pin of inverter U10 is connected to GND through capacitor C28, while the 1 pin of inverter U10 is connected to power voltage through resistor R85, while the 1 pin of inverter U10 is connected to the 16 pin of optocoupler U11; the 2 pin of inverter U10 is connected to the signal light color interface input end RED of the data processing and solving circuit; the 3 pin of inverter U10 is connected to GND through capacitor C27, while the 3 pin of inverter U10 is connected to power voltage through resistor R84, while the 3 pin of inverter U10 is connected to the 14 pin of optocoupler U11; the 4 pin of inverter U10 is connected to the signal light color interface input end YEL of the data processing and solving circuit; the 5 pin of inverter U10 is connected to GND through capacitor C26, while the 5 pin of inverter U10 is connected to power voltage through resistor R83, while the 5 pin of inverter U10 is connected to the 12 pin of optocoupler U11; the 6 pin of inverter U10 is connected to the signal light color interface input end GREEN of the data processing and solving circuit; the 1 pin of optocoupler U11 is connected to the zero line N of mains; the 2 pin of optocoupler U11 is connected to the first anode pin of TVS diode ZD8; the 3 pin of optocoupler U11 is connected to the zero line N of mains; the 4 pin of optocoupler U11 is connected to the first anode pin of TVS diode ZD2; the 5 pin of optocoupler U11 is connected to the zero line N of mains; the 6 pin of optocoupler U11 is connected to the first anode pin of TVS diode ZD7; the 11 pin of optocoupler U11 is connected to GND; the 13 pin of optocoupler U11 is connected to GND; the 15 pin of optocoupler U11 is connected to GND; the second anode pin of TVS diode ZD8 is connected to the first pin of resistor R130; the second pin of resistor R130 is connected to the first pin of resistor R139; the second pin of resistor R139 is the signal light interface R0; the second anode pin of TVS diode ZD2 is connected to the first pin of resistor R89; the second pin of resistor 89 is connected to the first pin of resistor R94; the second pin of resistor R94 is the signal light interface Y0; the second anode pin of TVS diode ZD7 is connected to the first pin of resistor R129; the second pin of resistor 129 is connected to the first pin of resistor R138; the second pin of resistor R138 is the signal light interface G0.

[0034] Chip U11 is a 4-way photoelectric coupling chip, used for photoelectric isolation of signal lamp input voltage, the circuit samples the state of the red, yellow and green lamp surfaces, a total of 3-way photoelectric coupling circuit of U11 is used. The signal lamp input AC220V voltage is a high voltage strong current signal, which cannot be directly input to the microcontroller U2, otherwise it will cause U2 chip damage. U11 converts the high voltage strong current signal at the input end of the signal lamp into an optical signal inside the chip, thereby electrically isolating it, and then restoring it to a low voltage weak current signal that can be input to U1, thereby realizing photoelectric isolation. Chip U10 is a 6-way Schmitt trigger inverter, which can convert slowly changing input signals into clear, non-jitter output signals, thereby converting the low voltage weak current signal output by U11 into a clear, non-jitter TTL level signal, while performing logic inversion. The circuit samples the state of the red, yellow and green lamp surfaces, a total of 3-way Schmitt trigger inverter of U10 is used; resistor R83 is the pull-up resistor for the output end of U11 photoelectric coupling circuit 3; resistor R84 is the pull-up resistor for the output end of U11 photoelectric coupling circuit 2; resistor R85 is the pull-up resistor for the output end of U11 photoelectric coupling circuit 1; resistors R89 and R94 are input end current limiting resistors for U11 photoelectric coupling circuit 2, resistors R129 and R138 are input end current limiting resistors for U11 photoelectric coupling circuit 3, resistors R130 and R139 are input end current limiting resistors for U11 photoelectric coupling circuit 1, the input end of U11 is connected to the high voltage strong current signal at the input end of the signal lamp, and the loop current value needs to be limited to the range that the photoelectric tube inside U11 can bear through the current limiting resistor; transient voltage suppression diode ZD2 is the input end voltage reduction diode for U11 photoelectric coupling circuit 2, ZD7 is the input end voltage reduction diode for U11 photoelectric coupling circuit 3, and ZD8 is the input end voltage reduction diode for U11 photoelectric coupling circuit 1. The input end of U11 is connected to the high voltage strong current signal at the input end of the signal lamp, and the transient voltage suppression diode can provide rapid overvoltage protection for the circuit, thereby reducing the voltage at the input end of the U11 photoelectric coupling circuit to a range that the chip can withstand; capacitor C26 is the filter capacitor for the output end of U11 photoelectric coupling circuit 3, C27 is the filter capacitor for the output end of U11 photoelectric coupling circuit 2, and C28 is the filter capacitor for the output end of U11 photoelectric coupling circuit 1.

[0035] In one embodiment of the application, the optocoupler U11 is a TLP620-4, the inverter U10 is a SN74HC14D, the resistor R83 is 10 kOhm, the resistor R84 is 10 kOhm, the resistor R85 is 10 kOhm, the resistor R89 is 27 kOhm, the resistor R94 is 27 kOhm, the resistor R129 is 27 kOhm, the resistor R130 is 27 kOhm, the resistor R138 is 27 kOhm, the resistor R139 is 27 kOhm, the transient voltage suppression diode ZD2 is a SMBJ120CA, the transient voltage suppression diode ZD7 is a SMBJ120CA, the transient voltage suppression diode ZD8 is a SMBJ120CA, the capacitor C26 is 1 uF, the capacitor C27 is 1 uF, and the capacitor C28 is 1 uF.

[0036] Referring to Figure 4In an embodiment of the present application, the data processing and calculation circuit in the circuit for calculating intersection saturation and stopping frequency of the present application comprises a microcontroller U2, an RS232 interface chip U14, resistors R1, R2, R3, R4, R5, R6, R88, R89, R90, R91, capacitors C1, C2, C3, C41, C42, C43, C44, C49, C50, C51, C52, wherein the pin 5 of the microcontroller U2 is connected to GND through the capacitor C2, the pin 5 of the microcontroller U2 is connected to the pin 6 of the microcontroller U2 through the resistor R1 and the resistor R2, the connection point of the resistor R1 and the resistor R2 is connected to GND through the capacitor C3, and the connection point of the resistor R1 and the resistor R2 is connected to the pin 5 of the microcontroller U2 through the crystal oscillator Y1; the pin 7 of the microcontroller U2 is connected to GND through the capacitor C1, and the pin 7 of the microcontroller U2 is connected to the power voltage through the resistor R3; the pin 60 of the microcontroller U2 is connected to GND through the resistor R4; the pin 13 of the microcontroller U2 is connected to the power voltage through the resistor R5; the pin 1 of the microcontroller U2 is connected to the power voltage; the pin 32 of the microcontroller U2 is connected to the power voltage; the pin 48 of the microcontroller U2 is connected to the power voltage; the pin 64 of the microcontroller U2 is connected to the power voltage; the pin 19 of the microcontroller U2 is connected to the power voltage; the pin 28 of the microcontroller U2 is connected to GND through the resistor R6; the pin 31 of the microcontroller U2 is connected to GND; the pin 47 of the microcontroller U2 is connected to GND; the pin 63 of the microcontroller U2 is connected to GND; the pin 18 of the microcontroller U2 is connected to GND; the pin 12 of the microcontroller U2 is connected to GND; the pin 16 TXD2 of the microcontroller U2 is connected to the pin 10 of the RS232 interface chip U14; the pin 17 RXD2 of the microcontroller U2 is connected to the pin 9 of the RS232 interface chip U14; the pin 29 TXD3 of the microcontroller U2 is connected to the pin 11 of the RS232 interface chip U14; the pin 30 RXD3 of the microcontroller U2 is connected to the pin 12 of the RS232 interface chip U14; the pin 42 of the microcontroller U2 is connected to the input end TXD1 of the vehicle detector interface circuit; the pin 43 of the microcontroller U2 is connected to the output end RXD1 of the vehicle detector interface circuit; the pin 44 of the microcontroller U2 is connected to the control end 485DIR of the vehicle detector interface circuit; the pin 24 of the microcontroller U2 is connected to the output end RED of the signal lamp color sampling circuit; the pin 25 of the microcontroller U2 is connected to the output end YEL of the signal lamp color sampling circuit; the pin 37 of the microcontroller U2 is connected to the output end GREEN of the signal lamp color sampling circuit; the pin 1 of the RS232 interface chip U14 is connected to the pin 3 of the RS232 interface chip U14 through the capacitor C41; the pin 4 of the RS232 interface chip U14 is connected to the pin 5 of the RS232 interface chip U14 through the capacitor C42; the pin 2 of the RS232 interface chip U14 is connected to the power voltage through the capacitor C43; the pin 6 of the RS232 interface chip U14 is connected to GND through the capacitor C44;The 16-pin of RS232 interface chip U14 is connected with power voltage; the 15-pin of RS232 interface chip U14 is connected with GND.

[0037] Chip U2 is a microcontroller, which is internally integrated with a timer, a memory, a serial communication interface, an IO input / output interface and other functions, and is a core device for data processing, calculating saturation and parking times; chip U14 is an RS232 interface chip, which converts the TTL level of the serial communication interface of U2 into the RS232 level, and is used for connecting with a serial port server and a router; resistance R1, resistance R2, crystal oscillator Y1, capacitor C2 and capacitor C3 form an external oscillator input circuit of the microcontroller U2, which mainly generates an accurate frequency signal, and provides a stable and synchronous basic clock signal for the internal operation of the microcontroller, so as to ensure that various operations of the microcontroller can be synchronized; C1 and R3 form a power-on reset circuit of the microcontroller U2, which is used for stably resetting the microcontroller U2 when the circuit is powered on; R4 is a pull-down resistance of the BOOT0 pin of U2, which is used for starting U2 from the internal flash memory; R5 is a series magnetic bead of the analog power supply VDDA of the microcontroller U2, which is used for ensuring the stability of the power supply and reducing interference; R6 is a pull-down resistance of the BOOT1 pin of U2, which is used for starting U2 from the internal flash memory; C41, C42, C43 and C44 are peripheral resistors of the charge pump circuit of chip U14, which help U14 to generate the required ±5.5V voltage; capacitor C49, capacitor C50, capacitor C51 and capacitor C52 are filter capacitors of the TTL data end pin of U14, which are used for ensuring the stability of the data waveform and reducing interference.

[0038] In an embodiment of the present application, the microcontroller U2 adopts STM32F103R8T6, the RS232 interface chip U14 adopts MAX3232, resistance R1 is 1M ohm, resistance R2 is 220 ohm, resistance R3 is 10k ohm, resistance R4 is 20k ohm, resistance R5 is 10 ohm magnetic bead, resistance R6 is 10k ohm, resistance R88 is 22 ohm, resistance R89 is 22 ohm, resistance R90 is 22 ohm, resistance R91 is 22 ohm, capacitor C1 is 0.1uF, capacitor C2 is 20pF, capacitor C3 is 20pF, capacitor C41 is 0.22uF, capacitor C42 is 0.22uF, capacitor C43 is 0.22uF, capacitor C44 is 0.22uF, capacitor C49 is 100pF, capacitor C50 is 100pF, capacitor C51 is 100pF, and capacitor C52 is 100pF.

[0039] In an embodiment of the present application, the circuit for calculating the saturation and the parking times of the intersection further comprises a data encryption and decryption circuit, which is shown in FIG. 2.Figure 5 The data encryption and decryption circuit of the application comprises an encryption chip U5, a capacitor C12 and a capacitor C13, wherein pin 1 of the data encryption chip U5 is connected with GND; pin 8 of the data encryption chip U5 is connected with a power supply voltage, at the same time, pin 8 of the data encryption chip is connected with GND through the capacitor C12, and pin 8 of the data encryption chip is connected with GND through the capacitor C13; pin 54 of the microcontroller U2 is connected with the input end SSEL1 of pin 6 of the data encryption chip U5; pin 55 of the microcontroller U2 is connected with the input end SCK1 of pin 4 of the data encryption chip U5; pin 56 of the microcontroller U2 is connected with the output end MISO1 of pin 2 of the data encryption chip U5; pin 57 of the microcontroller U2 is connected with the input end MOSI1 of pin 3 of the data encryption chip U5; and pin 58 of the microcontroller U2 is connected with the input end HSC_RST of pin 7 of the data encryption chip U5.

[0040] The data encryption and decryption circuit is used for encrypting and decrypting communication data between the circuit and a central control system or other devices, so as to ensure the safety of data transmission. Since the circuit is applied to the field of traffic signal control, the central control system or other devices in communication with the circuit are usually deployed in the public security network, and therefore have very high requirements for data transmission safety.

[0041] In an embodiment of the application, the encryption chip U5 adopts HSC32C1-S1V30, the capacitor C12 is 0.1uF, and the capacitor C13 is 10uF.

[0042] In an embodiment of the application, the 485 conversion chip U1, the inverter U10, the microcontroller U2, the data encryption chip U5, the RS232 interface chip U14 and the microcontroller U2 all adopt a power supply voltage of 3.3V. The unified power supply voltage can significantly simplify the design, and the devices with a power supply voltage of 3.3V usually have lower static current and dynamic power consumption, so that the power consumption and cost can be reduced. In addition, in differential communication such as RS-485, 3.3V power supply can reduce the risk of common-mode voltage interference and improve the reliability of long-distance transmission. Finally, the 3.3V system usually has smaller power supply ripple and noise, so that the system reliability can be improved. Of course, other suitable power supply voltages are also possible.

[0043] In an embodiment of the application, the circuit for calculating the saturation degree and the number of stops of the intersection of the application further comprises an Ethernet serial server, wherein pin 14 of the RS232 interface chip U14 is connected with the output end TXDOUT3 of the Ethernet serial server through the resistor R90, and pin 14 of the RS232 interface chip U14 is connected with GND through the capacitor C50; pin 13 of the RS232 interface chip U14 is connected with the input end RXDOUT3 of the Ethernet serial server through the resistor R88, and pin 13 of the RS232 interface chip U14 is connected with GND through the capacitor C52.

[0044] The circuit is applied to the field of traffic signal control, and needs to communicate with a central control system or other equipment. The Ethernet serial server is the wired communication circuit of the circuit. The central control system or other equipment communicating with the circuit is usually deployed in the public security network, and the Ethernet is the transmission mode specified by the public security network.

[0045] In an embodiment of the present application, the circuit for calculating intersection saturation and stopping times of the present application further comprises a router, wherein the 7th pin of the RS232 interface chip U14 is connected to the output end TXDOUT2 of the router through the resistor R89, and at the same time, the 7th pin of the RS232 interface chip U14 is connected to GND through the capacitor C51; the 8th pin of the RS232 interface chip U14 is connected to the input end RXDOUT2 of the router through the resistor R91, and at the same time, the 8th pin of the RS232 interface chip U14 is connected to GND through the capacitor C49.

[0046] The circuit is applied to the field of traffic signal control, and needs to communicate with a central control system or other equipment. The router is the wireless communication circuit of the circuit, which can use a 4G router or a 5G router. The wireless communication circuit is suitable for intersections connected by 4G / 5G without optical cable. The circuit can select wired communication or wireless communication according to actual application needs; in some application scenarios with high requirements for communication reliability, wired communication can also be used as the main communication circuit, and wireless communication can be used as the backup communication circuit, which switches to wireless communication when wired communication is unstable or interrupted.

Claims

1. A circuit for calculating intersection saturation and number of stops, characterized by, The vehicle detector interface circuit, the signal lamp color sampling circuit and the data processing and solving circuit are connected with each other, wherein, The vehicle detector interface circuit is electrically connected with the vehicle detector and the data processing and solving circuit, and is used for receiving real-time vehicle speed, vehicle number and queue length from the vehicle detector and transmitting the received real-time vehicle speed, vehicle number and queue length to the data processing and solving circuit; The signal lamp color sampling circuit is electrically connected with the traffic signal lamp and the data processing and solving circuit, and is used for sampling the light-on and light-off state of three colors of the traffic signal lamp and outputting the light-on and light-off state to the data processing and solving circuit; The data processing and solving circuit is used for receiving real-time vehicle speed, vehicle number and queue length from the vehicle detector interface circuit and receiving the light-on and light-off state of three colors from the signal lamp color sampling circuit, and processing and solving the received data to generate intersection saturation and vehicle parking times.

2. The circuit for calculating intersection saturation and number of stops according to claim 1, wherein, The vehicle detector interface circuit comprises a 485 conversion chip U1, resistors R21, R22, R23, R25, R29, R30 and R31, transient voltage suppression diodes D4 and D5, a GDT ceramic gas discharge tube G1 and a capacitor C8, wherein, The 1th pin of the 485 conversion chip U1 is connected with the vehicle detector interface input end RXD1 of the data processing and solving circuit through the resistor R21; the 2th pin of the 485 conversion chip U1 is connected with the 3th pin of the 485 conversion chip U1 and the vehicle detector interface control end 485DIR of the data processing and solving circuit through the resistor R25; the 4th pin of the 485 conversion chip U1 is connected with the vehicle detector interface output end TXD1 of the data processing and solving circuit through the resistor R31; the 5th pin of the 485 conversion chip U1 is connected with GND; the 6th pin of the 485 conversion chip U1 is connected with the 2th pin of the GDT ceramic gas discharge tube G1 through the resistor R30 and connected with the power voltage through the resistor R29, and is connected with GND through the transient voltage suppression diode D5; the 7th pin of the 485 conversion chip U1 is connected with GND through the resistor R22 and connected with GND through the transient voltage suppression diode D4, and is connected with the 1th pin of the GDT ceramic gas discharge tube G1 through the resistor R23; the 8th pin of the 485 conversion chip U1 is connected with GND through the capacitor C8 and connected with the power voltage; The 1th pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485A; the 2th pin of the GDT ceramic gas discharge tube G1 is the vehicle detector interface 485B; and the 3th pin of the GDT ceramic gas discharge tube G1 is connected with the ground EARTH.

3. The circuit for calculating intersection saturation and stops according to claim 2, wherein, The 485 conversion chip U1 adopts SP3485EN, the transient voltage suppression diode D4 adopts SMBJ10CA, the transient voltage suppression diode D5 adopts SMBJ10CA, the GDT ceramic gas discharge tube G1 adopts 3RL090L-6, and the power supply voltage is 3.3V.

4. The circuit for calculating intersection saturation and number of stops according to claim 1, wherein, The signal lamp color sampling circuit comprises an optocoupler U11, an inverter U10, resistors R83, R84, R85, R89, R94, R129, R130, R138, R139, transient voltage suppression diodes ZD2, ZD7, ZD8, capacitors C26, C27 and C28, wherein, The 1 pin of the inverter U10 is connected with GND through the capacitor C28, and simultaneously, the 1 pin of the inverter U10 is connected with the power supply voltage through the resistor R85, and simultaneously, the 1 pin of the inverter U10 is connected with the 16 pin of the optocoupler U11; the 2 pin of the inverter U10 is connected with the signal lamp color interface input end RED of the data processing and solving circuit; the 3 pin of the inverter U10 is connected with GND through the capacitor C27, and simultaneously, the 3 pin of the inverter U10 is connected with the power supply voltage through the resistor R84, and simultaneously, the 3 pin of the inverter U10 is connected with the 14 pin of the optocoupler U11; the 4 pin of the inverter U10 is connected with the signal lamp color interface input end YEL of the data processing and solving circuit; the 5 pin of the inverter U10 is connected with GND through the capacitor C26, and simultaneously, the 5 pin of the inverter U10 is connected with the power supply voltage through the resistor R83, and simultaneously, the 5 pin of the inverter U10 is connected with the 12 pin of the optocoupler U11; and the 6 pin of the inverter U10 is connected with the signal lamp color interface input end GREEN of the data processing and solving circuit. The 1 pin, 3 pin and 5 pin of the optocoupler U11 are connected with the power supply zero line N; the 2 pin of the optocoupler U11 is connected with the first anode pin of the TVS diode ZD8; the 4 pin of the optocoupler U11 is connected with the first anode pin of the TVS diode ZD2; the 6 pin of the optocoupler U11 is connected with the first anode pin of the TVS diode ZD7; and the 11 pin, 13 pin and 15 pin of the optocoupler U11 are connected with GND. The second anode pin of the TVS diode ZD8 is connected with the first pin of the resistor R130. The second pin of the resistor R130 is connected with the first pin of the resistor R139. The second pin of the resistor R139 is the signal lamp interface R0. The second anode pin of the TVS diode ZD2 is connected with the first pin of the resistor R89. The second pin of the resistor 89 is connected with the first pin of the resistor R94. The second pin of the resistor R94 is the signal lamp interface Y0. The second anode pin of the TVS diode ZD7 is connected with the first pin of the resistor R129. The second pin of the resistor 129 is connected with the first pin of the resistor R138. The second pin of the resistor R138 is the signal lamp interface G0.

5. The circuit for calculating intersection saturation and number of stops according to claim 4, wherein, The optocoupler U11 adopts TLP620-4, the inverter U10 adopts SN74HC14D, the transient voltage suppression diode ZD2 adopts SMBJ120CA, the transient voltage suppression diode ZD7 adopts SMBJ120CA, the transient voltage suppression diode ZD8 adopts SMBJ120CA, and the power supply voltage is 3.3V.

6. The circuit for calculating intersection saturation and number of stops according to claim 1, wherein, The data processing and solving circuit comprises a microcontroller U2, an RS232 interface chip U14, resistors R1, R2, R3, R4, R5, R6, R88, R89, R90, R91, capacitors C1, C2, C3, C41, C42, C43, C44, C49, C50, C51 and C52, wherein, The 5th pin of the microcontroller U2 is connected to GND through the capacitor C2, the 5th pin of the microcontroller U2 is connected to the 6th pin of the microcontroller U2 through the resistor R1 and the resistor R2, the connection point of the resistor R1 and the resistor R2 is connected to GND through the capacitor C3, and the connection point of the resistor R1 and the resistor R2 is connected to the 5th pin of the microcontroller U2 through the crystal oscillator Y1; the 7th pin of the microcontroller U2 is connected to GND through the capacitor C1, and the 7th pin of the microcontroller U2 is connected to the power voltage through the resistor R3; the 60th pin of the microcontroller U2 is connected to GND through the resistor R4; the 13th pin of the microcontroller U2 is connected to the power voltage through the resistor R5; the 1st, 19th, 32nd, 48th and 64th pins of the microcontroller U2 are connected to the power voltage; the 28th pin of the microcontroller U2 is connected to GND through the resistor R6; the 12th, 18th, 31st, 47th and 63rd pins of the microcontroller U2 are connected to GND; the 16th pin TXD2 of the microcontroller U2 is connected to the 10th pin of the RS232 interface chip U14; the 17th pin RXD2 of the microcontroller U2 is connected to the 9th pin of the RS232 interface chip U14; the 29th pin TXD3 of the microcontroller U2 is connected to the 11th pin of the RS232 interface chip U14; the 30th pin RXD3 of the microcontroller U2 is connected to the 12th pin of the RS232 interface chip U14; the 42nd pin of the microcontroller U2 is connected to the input end TXD1 of the vehicle detector interface circuit; the 43rd pin of the microcontroller U2 is connected to the output end RXD1 of the vehicle detector interface circuit; the 44th pin of the microcontroller U2 is connected to the control end 485DIR of the vehicle detector interface circuit; the 24th pin of the microcontroller U2 is connected to the output end RED of the signal lamp color sampling circuit; the 25th pin of the microcontroller U2 is connected to the output end YEL of the signal lamp color sampling circuit; and the 37th pin of the microcontroller U2 is connected to the output end GREEN of the signal lamp color sampling circuit. The 1st pin of the RS232 interface chip U14 is connected to the 3rd pin of the RS232 interface chip U14 through the capacitor C41; the 4th pin of the RS232 interface chip U14 is connected to the 5th pin of the RS232 interface chip U14 through the capacitor C42; the 2nd pin of the RS232 interface chip U14 is connected to the power voltage through the capacitor C43; the 6th pin of the RS232 interface chip U14 is connected to GND through the capacitor C44; the 16th pin of the RS232 interface chip U14 is connected to the power voltage; and the 15th pin of the RS232 interface chip U14 is connected to GND.

7. The circuit for calculating intersection saturation and number of stops according to claim 6, wherein, The microcontroller U2 adopts STM32F103R8T6, the RS232 interface chip U14 adopts MAX3232, and the power voltage is 3.3V.

8. The circuit for calculating intersection saturation and number of stops according to any one of claims 6 to 7, wherein, Further comprising data encryption and decryption circuit, data encryption and decryption circuit is used for the encryption and decryption of communication data, data encryption and decryption circuit includes data encryption chip U5, capacitor C12, capacitor C13, wherein, The 1 pin of the data encryption chip U5 is connected with GND; the 8 pin of the data encryption chip U5 is connected with power voltage, at the same time, the 8 pin of the data encryption chip is connected with GND through capacitor C12, at the same time, the 8 pin of the data encryption chip is connected with GND through capacitor C13; the 54 pin of the microcontroller U2 is connected with the 6 pin input end SSEL1 of the data encryption chip U5; the 55 pin of the microcontroller U2 is connected with the 4 pin input end SCK1 of the data encryption chip U5; the 56 pin of the microcontroller U2 is connected with the 2 pin output end MISO1 of the data encryption chip U5; the 57 pin of the microcontroller U2 is connected with the 3 pin input end MOSI1 of the data encryption chip U5; the 58 pin of the microcontroller U2 is connected with the 7 pin input end HSC_RST of the data encryption chip U5, wherein, the encryption chip U5 adopts HSC32C1-S1V30, and the power voltage is 3.3V.

9. The circuit for calculating intersection saturation and number of stops according to claim 8, wherein, Further comprising an Ethernet serial server, the Ethernet serial server is used for wired transmission of communication data, wherein, The 14 pin of the RS232 interface chip U14 is connected with the output end TXDOUT3 of the Ethernet serial server through resistor R90, at the same time, the 14 pin of the RS232 interface chip U14 is connected with GND through capacitor C50; the 13 pin of the RS232 interface chip U14 is connected with the input end RXDOUT3 of the Ethernet serial server through resistor R88, at the same time, the 13 pin of the RS232 interface chip U14 is connected with GND through capacitor C52.

10. The circuit for calculating intersection saturation and number of stops according to claim 8, wherein, Further comprising a router, the router is used for wireless transmission of communication data, wherein, The 7 pin of the RS232 interface chip U14 is connected with the output end TXDOUT2 of the router through resistor R89, at the same time, the 7 pin of the RS232 interface chip U14 is connected with GND through capacitor C51; the 8 pin of the RS232 interface chip U14 is connected with the input end RXDOUT2 of the router through resistor R91, at the same time, the 8 pin of the RS232 interface chip U14 is connected with GND through capacitor C49.

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