Urban waterlogging monitoring system and method based on synesthesia integrated millimeter wave radar

Abstract

The application discloses a kind of urban waterlogging monitoring systems and methods based on the perception integrated millimeter wave radar, the system includes: lamp pole body;Perception integrated millimeter wave radar module is installed on the lamp pole body, realizes the perception detection of water, gully and catchment area and the transmission reception of emergency communication signal;Edge intelligent analysis unit is used to process radar echo signal, calculate water depth, identify gully blockage state and monitor catchment range, and generate warning level;Multi-mode communication unit;Three-level emergency power supply unit;Communication mode switching unit is used to detect current communication link state, and automatically switch between public network communication, Mesh relay communication and extreme direct communication.It is integrated in lamp pole body using the technical scheme, realize road water depth, gully blockage state, catchment range all-weather high-precision monitoring, ensure continuous communication.

Description

Technical Field

[0001] This invention belongs to the field of emergency communication technology and relates to an urban flood monitoring system and method based on a sensor-integrated millimeter-wave radar. Background Technology

[0002] With the intensification of global climate change, urban flooding is becoming increasingly frequent, posing a serious threat to the safety of urban infrastructure and the protection of residents' travel. Currently, urban flooding monitoring mainly relies on equipment such as video surveillance, infrared sensors, and ultrasonic detectors, while communication transmission primarily uses 4G / 5G public networks and fiber optics. However, significant shortcomings have been exposed in practical applications:

[0003] 1. Failure of perception in severe weather: Video surveillance is affected by light attenuation and visibility in heavy rain, dense fog, and dark night, resulting in a significant decrease in recognition accuracy or even complete failure; infrared sensors are easily affected by ambient temperature, and ultrasonic signals are severely attenuated in rain and fog, making it impossible to accurately obtain key information such as water depth and blockage of rainwater inlets, leading to frequent missed alarms and false alarms.

[0004] 2. Communication links are extremely vulnerable: During extreme rainstorm disasters, base stations often lose power, optical fibers are broken, and public networks become congested and paralyzed. Traditional transmission methods that rely on public networks or optical fibers are completely interrupted, and monitoring data cannot be transmitted back to the city's smart brain, resulting in "blindness" in emergency command and delayed early warning.

[0005] 3. Data loss in extreme scenarios: Existing monitoring equipment mostly relies on a single mains power supply and lacks multi-level emergency power supply protection. The equipment will stop directly after a power outage. Even if some equipment is equipped with backup batteries, critical monitoring data cannot be transmitted in the absence of a communication link, forming data silos and affecting the efficiency of disaster relief.

[0006] 4. High cost of separating sensing and communication: In the existing solution, sensing devices and communication devices are independent of each other, requiring separate deployment and maintenance, resulting in a large amount of construction work, high costs, and difficulty in achieving full coverage of the city.

[0007] While existing technologies attempt to improve performance by optimizing sensor parameters or adding backup communication links, they have not fundamentally solved the three core pain points of "all-weather sensing in rain and fog," "self-healing communication across all scenarios," and "emergency response to extreme power outages and network disruptions." There is an urgent need for an integrated solution that combines sensing and communication, multi-level power supply, and multi-link communication to achieve full coverage and reliable protection for urban flood monitoring across all scenarios. Summary of the Invention

[0008] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing an urban flood monitoring system and method based on a sensor-integrated millimeter-wave radar.

[0009] To achieve the above objectives, the basic solution of the present invention is: an urban flood monitoring system based on a sensor-integrated millimeter-wave radar, comprising:

[0010] The light pole itself;

[0011] A sensor-integrated millimeter-wave radar module is installed on the light pole body and is used to transmit and receive FMCW waveforms;

[0012] The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals to calculate water depth, storm drain blockage thickness, and catchment area, and to determine whether it is waterlogging.

[0013] If there is waterlogging, an early warning will be issued.

[0014] The working principle and beneficial effects of this basic solution are as follows: This technical solution uses a radar module to simultaneously handle the sensing and detection of water accumulation, storm drains, and catchment areas, as well as the transmission and reception of emergency communication signals, eliminating the need for additional independent communication equipment and reducing system costs and construction workload. Edge intelligent analysis units are used to calculate water depth, storm drain blockage thickness, and catchment area area, determining whether urban flooding has occurred and issuing early warnings, achieving full coverage of urban flooding monitoring.

[0015] Furthermore, it also includes: a multi-mode communication unit, which includes a public network communication module, a millimeter-wave Mesh self-organizing network relay module, and an extreme environment direct connection communication unit;

[0016] The emergency power supply unit is connected to the integrated millimeter-wave radar module, the edge resolution unit, and the multi-mode communication unit, respectively.

[0017] The communication mode switching unit is used to detect the current communication link status and automatically switch between public network communication, Mesh relay communication and extreme direct connection communication.

[0018] By integrating a sensor-integrated millimeter-wave radar module, an edge intelligent analysis unit, a multi-mode communication unit, a three-level emergency power supply unit, and a communication mode switching unit into the light pole body, integrated urban flood monitoring and emergency communication are achieved.

[0019] The communication mode switching unit automatically switches between public network communication, Mesh relay communication, and extreme direct connection communication to ensure that the communication link is not interrupted in extreme scenarios.

[0020] Furthermore, the light pole body has a built-in modular installation compartment and wiring groove. The integrated millimeter-wave radar module, edge intelligent analysis unit, multi-mode communication unit, three-level emergency power supply unit, and communication mode switching unit are all installed in the modular installation compartment, and the wiring between each unit is set in the wiring groove.

[0021] By integrating and installing each unit inside the warehouse and setting the wiring in the wiring trough, the system can be modularly and integratedly deployed without the need for external redundant equipment. Construction is free from excavation and wiring, which greatly reduces the difficulty of on-site installation and construction period. The protection level can reach IP67, which can adapt to harsh outdoor environments. At the same time, it is easy to maintain and replace modules later, reducing maintenance costs by more than 50%.

[0022] The present invention also provides a method for monitoring urban flooding based on the system described in the present invention, comprising the following steps:

[0023] The integrated sensing millimeter-wave radar module continuously transmits FMCW waveforms and receives echo signals from the monitored area.

[0024] The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals, calculate water depth, storm drain blockage thickness, and catchment area, and determine whether it is waterlogging; if it is waterlogging, it issues an early warning.

[0025] This method continuously transmits FMCW waveforms and receives echo signals through an integrated sensing millimeter-wave radar module. Combined with the distance-Doppler feature extraction and judgment of the edge intelligent analysis unit, it achieves automatic identification of water depth, rainwater inlet status, and warning level.

[0026] Furthermore, the communication mode switching unit detects the link status of the multi-mode communication unit and executes the corresponding communication strategy:

[0027] When the public network is functioning normally, data is uploaded through the public network communication module;

[0028] When the public network is interrupted but the Mesh link is available, multi-hop transmission is achieved through the millimeter-wave Mesh self-organizing network relay module;

[0029] When both the public network and the Mesh link are interrupted, the extreme environment direct communication unit is activated to transmit data to emergency mobile terminals within 50 meters and simultaneously triggers local encrypted storage unit backup.

[0030] When an early warning is triggered, the local audible and visual alarm module activates tiered alarms, and the management platform generates a heat map of urban flooding and emergency dispatch instructions.

[0031] The communication mode switching unit adaptively executes a three-level communication strategy based on the link status. When the public network is normal, it uploads data through the public network. When the public network is interrupted, it automatically switches to Mesh multi-hop relay transmission. When both the public network and Mesh are interrupted, it initiates extreme environment direct communication to transmit data to emergency mobile terminals within 50 meters, ensuring that data can still be received by rescue personnel under extreme network-free conditions.

[0032] When an early warning is triggered, it is linked with local sound and light alarms and the city's smart brain to generate a heat map of urban flooding and emergency dispatch instructions, which improves the efficiency of emergency response.

[0033] Furthermore, the edge intelligent analysis unit, connected to the integrated sensing millimeter-wave radar module, processes the radar echo signal and calculates the water depth, storm drain blockage thickness, and catchment area using the following method:

[0034] Calculate the water depth at time t :

[0035]

[0036] Where c is the speed of light. For radar round trip time, The temperature and humidity compensation value was obtained through calibration experiments at different temperatures and humidity levels.

[0037] The time series data is smoothed using mean filtering to obtain the smoothed true water depth:

[0038]

[0039] in, This represents the smoothed, true water depth at the current moment. This is a collection of historical raw water depth data. is the number of sampling frames; k is the summation index variable used to traverse the sequence number of historical frame data;

[0040] Obtain radar echo intensity Calculate the radar cross section:

[0041]

[0042] in, These represent the radar transmitter's radio frequency transmission power, the transmitter antenna gain, and the receiver antenna gain, respectively. Radar cross-section of accumulated water / drainage inlets;

[0043] Quantitative inversion of storm drain blockage thickness:

[0044] ,

[0045] in, This represents the theoretical depth of water accumulation when the drain outlet is completely unobstructed and free of blockages, under the same rainfall. Indicates the deviation in water depth: express If the value is higher than the unobstructed baseline, drainage is obstructed and there is a blockage; the larger the difference, the more severe the blockage. The real-time blocking correction factor is dynamically adjusted based on the echo intensity ratio. This represents the basic congestion conversion factor, based on... Match the calibration data of the fishing village, identify the debris blocking the rainwater inlet, retrieve the blockage correction coefficient curve corresponding to the material based on the type of debris, and obtain the real-time blockage correction coefficient; This indicates the radar echo intensity under laboratory calibration with the drain outlet completely blocked. R represents the average echo intensity around the rainwater inlet as measured by real-time radar at the site. The effective blockage thickness of the drain inlet is indicated by the vertical thickness of the accumulated silt, sand, and debris on the surface of the grate, which is used to determine the level of blockage.

[0046] Calculate the area of ​​the catchment area ,for:

[0047]

[0048]

[0049] :

[0050] Calculate the rate of change of water depth :

[0051]

[0052] Where i represents the measured rainfall intensity, The amount of water discharged from the rainwater inlet. The total area of ​​the drain opening. K represents the baseline drainage coefficient for unblocked rainwater inlets; K is the pre-stored calibration curve of the equipment. The larger the value, the more severe the blockage; the smaller the value, the greater the blockage.

[0053] Mean filtering is used to smooth time-series data, effectively eliminating instantaneous noise and random fluctuations, and improving data stability. Temperature and humidity compensation is incorporated into the calculation of water depth to correct for the influence of environmental factors on radar ranging, improving measurement accuracy to ±2 mm.

[0054] Quantitative analysis of radar echo energy using radar echo intensity formulas helps distinguish water surfaces from other ground targets. Calculation of area provides a basis for dynamic water catchment analysis, enabling quantitative inversion of storm drain blockage thickness, elevating blockage status from qualitative judgment to quantitative detection, and providing more accurate input parameters for analyzing the causes of urban flooding and determining early warning levels.

[0055] Furthermore, based on distance-Doppler characteristics, the method for determining whether it is urban flooding is as follows:

[0056] Level 1: Eliminate temporary, false water accumulation.

[0057] like <0 indicates that the water depth has receded, meaning there is only temporary flooding and no actual flooding.

[0058] like ≥0 indicates that the water level continues to rise or does not recede, thus entering Level II;

[0059] Second level: Eliminate static stagnant water and calculate the rate of expansion of the water accumulation area. :

[0060]

[0061] in, , Indicates time , The corresponding catchment area;

[0062] like This indicates that the area remains unchanged, the water is static and stagnant, and there is no flooding.

[0063] like > The threshold indicates that the water level continues to expand and enters the third level;

[0064] Level 3: Water flow confluence dynamics assessment, identifying actual water flow accumulation:

[0065] The monitoring area is divided into grids, and the consistency of the angle between the water flow and the rainwater inlet in each grid is calculated:

[0066]

[0067] in, The coordinates of the center of the storm drain are (monitoring reference point, coordinates pre-entered by municipal surveying). This represents the planar coordinates of the center point of the i-th grid cell (the monitoring area is uniformly divided into square grids, with a preferred size of 2m × 2m for each cell). , This represents the components of the water flow velocity in the i-th grid cell on the X and Y coordinate axes. For grid water flow vectors, This represents the magnitude of the flow velocity (combined velocity) of the i-th grid cell. The angle between the direction of water flow through the grid and the line connecting the grid to the storm drain inlet. The closer to 1: →0°, water flow is directed towards the rainwater inlet (effective catchment grid); When the value is ≥0.7, the grid cell is counted as a valid grid cell in the bus.

[0068] Define the confluence coefficient λ:

[0069]

[0070] If λ < 0.6, it indicates that the water flow is scattered, i.e., ordinary water accumulation;

[0071] If λ≥0.6, it indicates that a large area of ​​water flows towards the drainage outlet and enters the fourth level of final review;

[0072] Level 4: Determination of the causes of waterlogging:

[0073] like <2cm indicates good drainage and no waterlogging;

[0074] like ≥2cm indicates obstructed drainage and water accumulation that cannot be discharged in time; all four conditions are met: it is determined to be a real road flooding hazard;

[0075] Final flood assessment:

[0076]

[0077] IsFlood indicates the final flood assessment result.

[0078] The four-level progressive judgment mechanism significantly improves the accuracy of urban flooding early warning and effectively avoids the common problems of missed and false alarms in traditional single-threshold early warning schemes.

[0079] Furthermore, the criteria for determining the warning level are as follows:

[0080] Level 1 Warning: Water depth > 15cm, or complete blockage of storm drains, or expansion of the catchment area by ≥ 50% within 10 minutes;

[0081] Level 2 warning: water depth 5-15cm, or slight blockage of storm drains, or slow expansion of the catchment area.

[0082] Accurate early warnings facilitate use. Attached Figure Description

[0083] Figure 1 This is a flowchart illustrating the urban flooding monitoring method of the present invention;

[0084] Figure 2 This is a topology map of a 5-square-kilometer area for the urban flood monitoring system based on a sensor-integrated millimeter-wave radar, as described in this invention. Detailed Implementation

[0085] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0086] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0087] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0088] This invention discloses an urban flooding monitoring system based on a sensor-integrated millimeter-wave radar, comprising:

[0089] The light pole itself can be a municipal standard 6–12m light pole.

[0090] The (77GHz) integrated millimeter-wave radar module is installed on the light pole body, preferably in the lower middle part of the light pole, projecting downwards at 15°–30° to cover the road surface, rainwater inlets and catchment areas. It adopts the FMCW system, operates in the 76–81GHz frequency band, has a detection range of 0.1–30m, a resolution of ±2mm, and has rain and fog penetration and non-contact detection capabilities. It reuses the radar frequency band to realize sensing and communication functions.

[0091] The integrated sensing millimeter-wave radar module adopts ultra-large-scale MIMO beamforming technology to generate a concentrated directional beam. The signal attenuation is ≤3dB in rain and fog environments. It can penetrate rain curtains and dense fog with a thickness of ≤5cm and is not affected by light, temperature and humidity.

[0092] The integrated millimeter-wave radar module is used to transmit and receive FMCW waveforms, and simultaneously realizes the perception and detection of water accumulation, rainwater inlets and catchment areas, as well as the transmission and reception of emergency communication signals. Through the rain and fog penetration and non-contact detection characteristics of 77GHz millimeter waves, it can achieve all-weather high-precision monitoring of road water depth, rainwater inlet blockage status and catchment spread range, completely solving the technical defects of traditional video surveillance in the failure of recognition in heavy rain, dense fog and dark night environments.

[0093] The edge intelligent analysis unit is connected to the integrated millimeter-wave radar module to process radar echo signals, calculate water depth, storm drain blockage thickness and catchment area, and determine whether it is waterlogging.

[0094] If there is waterlogging, an early warning will be issued.

[0095] In a preferred embodiment of the present invention, the urban flooding monitoring system based on integrated sensing millimeter-wave radar further includes:

[0096] The multi-mode communication unit includes a public network communication module, a millimeter-wave mesh self-organizing network relay module, and an extreme environment direct connection communication unit. The millimeter-wave mesh self-organizing network relay module supports OFDM modulation and self-organizing network routing protocols, with a single-hop communication distance of 80–150m and supports up to 8 relays to form a regional emergency communication network.

[0097] The extreme environment direct communication unit reuses the 77GHz radar band, eliminating the need for public networks or mesh relays, enabling point-to-point direct communication between a single terminal and emergency mobile terminals within 50m; it employs millimeter-wave narrowband modulation technology, achieving a communication rate ≥1Mbps and a bit error rate ≤10⁻ 6 It supports emergency personnel in directly receiving core data via handheld emergency terminals.

[0098] The 77GHz millimeter wave wavelength is 1.6–3.9 mm, much smaller than the diameter of raindrops, and rain and fog have minimal signal attenuation. The dielectric constants of water and air differ significantly (water εr≈80, air εr≈1), resulting in high echo signal intensity from the water surface, making it easy to distinguish from other targets. The distance changes between the radar and the ground and water surface are measured using FMCW technology, and the water depth is calculated using a dielectric constant model. The blockage status of rainwater inlets is determined by the abrupt changes and fluctuations in echo energy. The catchment area is monitored by the echo distribution of multiple distance cells.

[0099] Under normal operating conditions, it utilizes the public network for high-speed transmission; when the public network is interrupted, it uses a Mesh self-organizing network for multi-hop relay; in extreme situations where there is no network or relay, it reuses the 77GHz radar frequency band to achieve point-to-point direct communication, ensuring that data can be received through emergency mobile terminals.

[0100] The three-level emergency power supply unit is electrically connected to the integrated millimeter-wave radar module, edge resolution unit, and multi-mode communication unit. It features overvoltage, overcurrent, and short-circuit protection. The supercapacitor module uses graphene-based materials, with a charging time of ≤10 minutes and a cycle life of ≥100,000 cycles. When the mains power is normal, it powers the system and charges the lithium battery; when the mains power is interrupted, it automatically switches to the lithium battery, providing ≥8 hours of continuous operation; when the lithium battery is depleted, the supercapacitor emergency power supply is activated, providing ≥30 minutes of continuous operation, ensuring uninterrupted core functions under extreme power outage scenarios. The supercapacitor, made of graphene-based materials, offers fast charging speed and long cycle life, making it suitable for emergency scenarios.

[0101] The communication mode switching unit detects the current communication link status and automatically switches between public network communication, Mesh relay communication, and extreme direct connection communication. In extreme scenarios such as 4G / 5G network failure, fiber optic interruption, or even complete power failure of a single terminal, point-to-point emergency communication can be achieved through millimeter-wave band reuse technology. Combined with supercapacitor emergency power supply and local data backup, it can achieve full-domain emergency protection of "uninterrupted sensing, uninterrupted communication, and no data loss".

[0102] Utilizing integrated sensing technology, the FMCW waveform emitted by the radar module can be used for both sensing and carrying communication data. Mesh relay communication is achieved through OFDM modulation, and direct communication in extreme environments is achieved through narrowband modulation. The Mesh self-organizing network supports automatic node discovery, automatic route selection, and automatic detour for link failures, ensuring self-healing of the communication network within the area. Directional beams are used for extreme direct communication to improve anti-interference capabilities and communication distance.

[0103] This system is applicable to complex scenarios such as urban main roads, low-lying sections, underpasses, and areas with dense storm drains. It provides a reliable end-to-end solution for urban flood monitoring and emergency command, fundamentally solving the problem of delayed early warning caused by perception failure and communication interruption in harsh environments.

[0104] In a preferred embodiment of the present invention, the light pole body has a built-in modular installation compartment and wiring groove. The integrated millimeter-wave radar module, edge intelligent analysis unit, multi-mode communication unit, three-level emergency power supply unit, and communication mode switching unit are all installed in the modular installation compartment, and the wiring between each unit is arranged in the wiring groove.

[0105] By integrating and installing each unit inside the warehouse and setting the wiring in the wiring trough, the system can be modularly and integratedly deployed without the need for external redundant equipment. Construction is free from excavation and wiring, which greatly reduces the difficulty of on-site installation and construction period. The protection level can reach IP67, which can adapt to harsh outdoor environments. At the same time, it is easy to maintain and replace modules later, reducing maintenance costs by more than 50%.

[0106] In a preferred embodiment of the present invention, the urban flooding monitoring system further includes a local audible and visual alarm module installed on the light pole body. The control terminal of the local audible and visual alarm module is electrically connected to the warning level signal output terminal of the edge intelligent analysis unit. For example, the local audible and visual alarm module triggers graded alarms according to the warning level: a level one warning triggers a flashing red light and a high-decibel buzzer; a level two warning triggers a constantly lit yellow light and a low-noise prompt.

[0107] In a preferred embodiment of the present invention, the urban flooding monitoring system further includes a local encrypted storage unit for caching monitoring data and automatically retransmitting it after communication interruption or power failure. In end-user scenarios, it automatically stores key data from the most recent hour, with a sampling frequency of once per minute. The data is encrypted to prevent leakage, and automatically retransmitted to the city's smart brain after power failure to avoid data loss.

[0108] The local encrypted storage unit performs encrypted backup of data in extreme scenarios and automatically retransmits the data after power failure to ensure that the data is not lost; the communication process uses encrypted transmission to prevent data leakage and meet the municipal data security requirements.

[0109] The three-level emergency power supply unit includes a mains power input module, a lithium battery backup module, and a supercapacitor emergency module. When the mains power is interrupted, it automatically switches to the lithium battery (with a battery life of ≥8 hours). When the lithium battery is depleted, it activates the supercapacitor (with a battery life of ≥30 minutes) to provide continuous power to the entire system.

[0110] The link detection period of the communication mode switching unit is 100ms, and the switching delay is ≤20ms.

[0111] This system uses municipal standard smart light poles as its carrier and integrates a 77GHz integrated millimeter-wave radar module, an edge intelligent analysis unit, a millimeter-wave Mesh self-organizing network relay module, a three-level emergency power supply unit, an extreme environment direct connection communication unit, a local encrypted storage unit, a local audible and visual alarm module, and a communication mode switching unit. All modules are integrated inside the light pole to form an integrated design, eliminating the need for external redundant equipment and making deployment convenient.

[0112] This invention overcomes the limitations of harsh environments such as rain, fog, and darkness, achieving high-precision, all-weather sensing of key parameters related to urban flooding. It constructs a three-tiered communication link—"public network - Mesh - direct connection"—ensuring uninterrupted communication even in extreme scenarios. A three-tiered emergency power supply system is designed to ensure continued operation after power outages, preventing data loss. The integrated sensing and communication design reduces deployment and maintenance costs, making it suitable for large-scale applications across entire cities.

[0113] Preferred, such as Figure 2As shown, this system is deployed in a 5-square-kilometer urban flood monitoring demonstration area. It uses municipal standard 10m smart light poles and evenly deploys 500 monitoring nodes at 30-50m intervals, covering main roads, secondary roads, low-lying sections, underpasses and areas with dense storm drains.

[0114] Each light pole is equipped with a 77GHz integrated millimeter-wave radar module in its lower middle section, projecting downwards at a 25° angle to cover a monitoring area with a radius of 15m. This ensures that a single node can cover 1–2 rainwater inlets and surrounding drainage surfaces. The edge intelligent analysis unit, millimeter-wave mesh relay module, three-level emergency power supply unit, and local encrypted storage unit are integrated into a waterproof sealed compartment at the top of the light pole, with an IP67 protection rating, suitable for harsh outdoor environments. The local audible and visual alarm module is installed in the upper middle section of the light pole at a height of 2.5m for easy observation by on-site personnel.

[0115] This invention also provides a method for monitoring urban flooding based on the system described in this invention, such as... Figure 1 As shown, it includes the following steps:

[0116] The integrated sensing millimeter-wave radar module continuously transmits FMCW waveforms and receives echo signals from the monitored area.

[0117] The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals, calculate water depth, storm drain blockage thickness, and catchment area, and determine whether it is waterlogging; if it is waterlogging, it issues an early warning.

[0118] In a preferred embodiment of the present invention,

[0119] The communication mode switching unit detects the link status of the multi-mode communication unit and executes the corresponding communication strategy:

[0120] When the public network is functioning normally, data is uploaded through the public network communication module;

[0121] When the public network is interrupted but the Mesh link is available, multi-hop transmission is achieved through the millimeter-wave Mesh self-organizing network relay module;

[0122] When both the public network and the Mesh link are interrupted, the extreme environment direct communication unit is activated to transmit data to emergency mobile terminals within 50 meters and simultaneously triggers local encrypted storage unit backup.

[0123] When an early warning is triggered, the local audible and visual alarm module activates tiered alarms, and the management platform generates a heat map of urban flooding and emergency dispatch instructions.

[0124] After the public network was interrupted, the communication mode switching unit detected the link abnormality within 100ms and automatically switched to the Mesh self-organizing network mode. Each monitoring node transmitted data to two aggregation nodes in the regional center through multi-hop relay between light poles. The aggregation nodes then uploaded the data to the city's smart brain through backup optical fiber. During the test, the edge nodes had a maximum of 4 hops, the data transmission delay was ≤150ms, and there was no data loss.

[0125] Simulating extreme scenarios such as mains power outage, lithium battery depletion, and both public network and Mesh network interruption, the supercapacitor automatically activates, and the system switches to extreme emergency mode; the radar module reduces the sampling frequency to 1 time / minute to ensure the supercapacitor's battery life is ≥30 minutes; the extreme environment direct communication unit activates, transmitting core data (water depth, blockage status, and warning level) to emergency personnel's handheld emergency terminals within 50 meters; emergency personnel can view the data locally on their terminals or forward it to the city's smart brain via mobile hotspot; a total of 15 sets of data are transmitted within 30 minutes of power outage, with a 0% error rate and 100% data integrity; after power outage is restored, the local encrypted storage unit automatically retransmits the backup data from the past 30 minutes, with no data loss.

[0126] The link detection period of the communication mode switching unit is 100ms, and the switching delay is ≤20ms, ensuring seamless switching of communication links.

[0127] The communication mode switching unit adaptively executes a three-level communication strategy based on the link status. When the public network is normal, it uploads data through the public network. When the public network is interrupted, it automatically switches to Mesh multi-hop relay transmission. When both the public network and Mesh are interrupted, it initiates extreme environment direct communication to transmit data to emergency mobile terminals within 50 meters, ensuring that data can still be received by rescue personnel under extreme network-free conditions.

[0128] The emergency mobile terminal supports 77GHz signal reception and data decoding, and can forward data to the city's smart brain via Bluetooth and WiFi, or store it locally for emergency responders to view. The city's smart brain integrates and analyzes data uploaded from multiple nodes to generate a regional flooding risk assessment report, and coordinates emergency dispatch with drainage pumping stations, smart manhole covers, and other equipment. This system seamlessly integrates with the city's smart brain, automatically generating flooding heat maps, emergency work orders, and dispatch instructions, and coordinating emergency dispatch with drainage pumping stations, smart manhole covers, and other equipment, shortening emergency response time by more than 50% and improving the efficiency of urban flooding emergency response.

[0129] In environments of heavy rain (50 mm / h) and dense fog (50 m visibility), traditional video surveillance is completely unable to identify water accumulation and the status of drain outlets. This system's radar module has a signal attenuation of only 2 dB, a water depth measurement error of ≤3 mm, a 100% accuracy rate in identifying drain outlet blockages, and a water catchment area monitoring deviation of ≤5%, fully meeting the requirements for emergency monitoring.

[0130] In a preferred embodiment of the present invention, the edge intelligent analysis unit is connected to the integrated sensing millimeter-wave radar module and is used to process the radar echo signal to calculate the water depth, the thickness of the storm drain blockage, and the area of ​​the catchment area.

[0131] Calculate the water depth at time t :

[0132]

[0133] Where c is the speed of light. For radar round-trip time, the optimal time is... (Sampling period 5 minutes); The temperature and humidity compensation values ​​were obtained through calibration experiments at different temperatures and humidity levels. , ℃, b=0.00012m / %RH; T is the ambient temperature, RH is the relative humidity of the air;

[0134] The time series data is smoothed using mean filtering to obtain the smoothed true water depth:

[0135]

[0136] in, This represents the smoothed, true water depth at the current moment. This is a collection of historical raw water depth data. N is the number of sampling frames, ranging from 8 to 32, with N=16 being preferred; k is the summation index variable, used to traverse the sequence number of historical frame data.

[0137] Obtain radar echo intensity Calculate the radar cross section:

[0138]

[0139] in, These represent the radar transmitter's radio frequency transmission power, the transmitter antenna gain, and the receiver antenna gain, respectively. The radar cross-section of accumulated water / drainage inlet debris (key: the ability of accumulated water and silt blockage to reflect electromagnetic waves; the thicker the blockage, the larger c is and the stronger the echo R).

[0140] Quantitative inversion of storm drain blockage thickness:

[0141] ,

[0142] in, This represents the theoretical water depth (calibrated value) when the drain outlet is completely unobstructed and free of blockages under the same rainfall. This indicates the actual water depth around the rainwater inlet, as calculated in real time by radar. Indicates the deviation in water depth: This indicates that the measured water accumulation is higher than the unobstructed baseline value, indicating that drainage is blocked or there is a blockage; the larger the difference, the more severe the blockage. The real-time blocking correction factor is dynamically adjusted based on the echo intensity ratio. This represents the basic blockage conversion factor (factory calibration constant, inherent conversion factor for silt / leaf debris), based on... By matching the calibration data of the fishing village, identifying the debris clogging the rainwater inlets, and retrieving the corresponding clogging correction coefficient curve based on the type of debris, the real-time clogging correction coefficient is obtained; laboratory calibration benchmark values ​​are also used. Siltation withered branches and fallen leaves ;

[0143] This indicates the radar echo intensity under laboratory calibration with the drain outlet completely blocked (taken from the echo formula R on this page). This represents the average echo intensity around the rainwater inlet as measured by real-time radar at the site. The effective blockage thickness of the drain inlet is indicated by the vertical thickness of the accumulated silt, sand, and debris on the surface of the grate, which is used to determine the level of blockage.

[0144] Calculate the area of ​​the catchment area ,for:

[0145]

[0146]

[0147] :

[0148] Calculate the rate of change of water depth :

[0149]

[0150] Where i represents the measured rainfall intensity, The amount of water discharged from the rainwater inlet. The total area of ​​the drain opening. The optimal drainage coefficient for non-clogging storm drains is selected. K represents the pre-stored calibration curve of the equipment. The larger the value, the more severe the blockage; the smaller the value, the greater the blockage.

[0151] In a preferred embodiment of the present invention, the method for determining whether there is waterlogging based on distance-Doppler characteristics is as follows:

[0152] First level: Eliminate momentary false water accumulation, if <0 indicates that the water depth has receded, meaning there is only temporary flooding and no actual flooding.

[0153] like ≥0 indicates that the water level continues to rise or does not recede, thus entering Level II;

[0154] Second level: Eliminating static stagnant water, calculating the rate of expansion of the water accumulation area:

[0155]

[0156] in, , Indicates time , The corresponding catchment area;

[0157] like This indicates that the area remains unchanged, the water is static and stagnant, and there is no flooding.

[0158] like > Threshold ( The preset range (e.g., 0.005-0.012 m / min, preferably 0.008 m / min) indicates that the water level is continuing to expand and has entered the third level.

[0159] Level 3: Water flow confluence dynamics assessment, identifying actual water flow accumulation:

[0160] The monitoring area is divided into grids, and the consistency of the angle between the water flow and the rainwater inlet in each grid is calculated:

[0161]

[0162] in, The coordinates of the center of the storm drain are (monitoring reference point, coordinates pre-entered by municipal surveying). This represents the planar coordinates of the center point of the i-th grid cell (the monitoring area is uniformly divided into square grids, with a preferred size of 2m × 2m for each cell). , This represents the components of the water flow velocity in the i-th grid cell on the X and Y coordinate axes. For grid water flow vectors, This represents the magnitude of the flow velocity (combined velocity) of the i-th grid cell. The angle between the direction of water flow through the grid and the line connecting the grid to the storm drain inlet. The closer to 1: →0°, water flow is directed towards the rainwater inlet (effective catchment grid); When the value is ≥0.7, the grid cell is counted as a valid grid cell in the bus.

[0163] Define the confluence coefficient λ:

[0164]

[0165] If λ < 0.6, it indicates that the water flow is scattered, i.e., ordinary water accumulation;

[0166] If λ≥0.6, it indicates that a large area of ​​water flows towards the drainage outlet and enters the fourth level of final review;

[0167] Level 4: Determination of the causes of waterlogging:

[0168] If 0 <2cm indicates good drainage and no waterlogging;

[0169] like ≥2cm indicates obstructed drainage and water accumulation that cannot be discharged in time; all four conditions are met: it is determined to be a real road flooding hazard;

[0170] Final flood assessment:

[0171]

[0172] IsFlood indicates the final flood assessment result.

[0173] The first-level time-domain steady-state determination calculates the rate of change of water depth to eliminate instantaneous false water accumulation signals caused by raindrops splashing or vehicles passing by, thus avoiding false alarms.

[0174] The second-level spatial spread determination distinguishes between static stagnant water and continuously expanding real water accumulation by calculating the expansion rate of the water accumulation area, further reducing the false alarm rate.

[0175] The third-level water flow confluence dynamics determination identifies ordinary water accumulation and real water flow with a clear confluence path by dividing the grid and calculating the consistency of the angle between the water flow and the rainwater inlet and the confluence coefficient.

[0176] The fourth-level blockage coupling final review determines the degree of drainage obstruction by quantitatively inverting the blockage thickness. Only when all four conditions are met is it finally determined to be a real road flooding hazard.

[0177] In a preferred embodiment of the present invention, the warning level determination criterion based on distance-Doppler characteristics is as follows:

[0178] Level 1 Warning: Water depth > 15cm, or complete blockage of storm drains, or expansion of the catchment area by ≥ 50% within 10 minutes;

[0179] Level 2 warning: water depth 5-15cm, or slight blockage of storm drains, or slow expansion of the catchment area.

[0180] The specific embodiments described herein are merely illustrative examples of the present invention. Those skilled in the art can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the technology of the present invention or exceeding the scope defined by the appended claims.

[0181] In the embodiments of this application, terms such as "fixed," "fixed connection," and "fixed connection" refer to common fixing methods in the prior art, such as welding, riveting, and screws. "Rotary connection" refers to common rotary connection methods in the prior art, such as hinges and bearing rotation. If electrical components are provided, the functions, control, and power supply methods of all electrical components are common technical means in the prior art. This application has not improved them and they are not within the protection scope of this application. Therefore, this application will not elaborate on them.

[0182] Furthermore, the selection of materials and strength limitations for all components in this application can be made and arranged by those skilled in the art based on the site environment and the requirements of relevant national or industry standards, and are not within the scope of protection of this application. Therefore, this application will not elaborate on these points.

Claims

1. An urban flood monitoring system based on a sensor-integrated millimeter-wave radar, characterized in that, include: The light pole itself; A sensor-integrated millimeter-wave radar module is installed on the light pole body and is used to transmit and receive FMCW waveforms; The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals to calculate water depth, storm drain blockage thickness, and catchment area, and to determine whether it is waterlogging. If there is waterlogging, an early warning will be issued.

2. The urban flood monitoring system based on integrated sensing millimeter-wave radar according to claim 1, characterized in that, Also includes: A multi-mode communication unit, comprising a public network communication module, a millimeter-wave Mesh self-organizing network relay module, and an extreme environment direct connection communication unit; The emergency power supply unit is connected to the integrated millimeter-wave radar module, the edge resolution unit, and the multi-mode communication unit, respectively. The communication mode switching unit is used to detect the current communication link status and automatically switch between public network communication, Mesh relay communication and extreme direct connection communication.

3. The urban flood monitoring system based on a sensor-integrated millimeter-wave radar according to claim 1, characterized in that, The light pole body has a built-in modular installation compartment and wiring groove. The integrated millimeter-wave radar module, edge intelligent analysis unit, multi-mode communication unit, emergency power supply unit, and communication mode switching unit are all installed in the modular installation compartment, and the wiring between each unit is set in the wiring groove.

4. A method for monitoring urban flooding based on the system described in any one of claims 1-3, characterized in that, Includes the following steps: The integrated sensing millimeter-wave radar module continuously transmits FMCW waveforms and receives echo signals from the monitored area. The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals, calculate water depth, storm drain blockage thickness, and catchment area, and determine whether it is flooding; if it is flooding, it will issue an early warning.

5. The urban flooding monitoring method according to claim 4, characterized in that, The communication mode switching unit detects the link status of the multi-mode communication unit and executes the corresponding communication strategy: When the public network is functioning normally, data is uploaded through the public network communication module; When the public network is interrupted but the Mesh link is available, multi-hop transmission is achieved through the millimeter-wave Mesh self-organizing network relay module; When both the public network and the Mesh link are interrupted, the extreme environment direct communication unit is activated to transmit data to emergency mobile terminals within 50 meters and simultaneously triggers local encrypted storage unit backup. When an early warning is triggered, the local audible and visual alarm module activates tiered alarms, and the management platform generates a heat map of urban flooding and emergency dispatch instructions.

6. The urban flooding monitoring method according to claim 4, characterized in that, The edge intelligent analysis unit, connected to the integrated millimeter-wave radar module, is used to process radar echo signals and calculate the water depth, storm drain blockage thickness, and catchment area using the following method: Calculate the water depth at time t : Where c is the speed of light. For radar round-trip time, The temperature and humidity compensation value was obtained through calibration experiments at different temperatures and humidity levels. The time series data is smoothed using mean filtering to obtain the smoothed true water depth: in, This represents the smoothed, true water depth at the current moment. This is a collection of historical raw water depth data. is the number of sampling frames; k is the summation index variable used to traverse the sequence number of historical frame data; Obtain radar echo intensity Calculate the radar cross section: in, These represent the radar transmitter's radio frequency transmission power, the transmitter antenna gain, and the receiver antenna gain, respectively. Radar cross-section of accumulated water / drainage inlets; Quantitative inversion of storm drain blockage thickness: ， in, This represents the theoretical depth of water accumulation when the drain outlet is completely unobstructed and free of blockages, under the same rainfall. Indicates the deviation in water depth: express If the value is higher than the unobstructed baseline, drainage is obstructed and there is a blockage; the larger the difference, the more severe the blockage. The real-time blocking correction factor is dynamically adjusted based on the echo intensity ratio. This represents the basic congestion conversion factor, based on... Match the calibration data of the fishing village, identify the debris blocking the rainwater inlet, retrieve the blockage correction coefficient curve corresponding to the material based on the type of debris, and obtain the real-time blockage correction coefficient; This indicates the radar echo intensity under laboratory calibration with the drain outlet completely blocked. This represents the average echo intensity around the rainwater inlet as measured by real-time radar at the site. The effective blockage thickness of the drain inlet is indicated by the vertical thickness of the accumulated silt, sand, and debris on the surface of the grate, which is used to determine the level of blockage. Calculate the area of ​​the catchment area ,for: ： Calculate the rate of change of water depth : Where i represents the measured rainfall intensity, The amount of water discharged from the rainwater inlet. The total area of ​​the drain opening. K represents the baseline drainage coefficient for unblocked rainwater inlets; K is the pre-stored calibration curve of the equipment. The larger the value, the more severe the blockage; the smaller the value, the greater the blockage.

7. The urban flooding monitoring method according to claim 6, characterized in that, The method for determining whether there is urban flooding based on distance-Doppler characteristics is as follows: First level: Eliminate momentary false water accumulation, if <0 indicates that the water depth has receded, meaning there is only temporary flooding and no actual flooding. like ≥0 indicates that the water level continues to rise or does not recede, thus entering Level II; Second level: Eliminate static stagnant water and calculate the rate of expansion of the water accumulation area. : in, , Indicates time , The corresponding catchment area; like This indicates that the area remains unchanged, the water is static and stagnant, and there is no flooding. like > Threshold This indicates that the floodwaters have continued to expand and have entered the third level. Level 3: Water flow confluence dynamics assessment, identifying actual water flow accumulation: The monitoring area is divided into grids, and the consistency of the angle between the water flow and the rainwater inlet in each grid is calculated: in, The coordinates of the center of the storm drain are (monitoring reference point, coordinates pre-entered by municipal surveying). This represents the planar coordinates of the center point of the i-th grid cell (the monitoring area is uniformly divided into square grids); , This represents the components of the water flow velocity in the i-th grid cell on the X and Y coordinate axes. For grid water flow vectors, This represents the magnitude of the flow velocity (combined velocity) of the i-th grid cell. The angle between the direction of water flow through the grid and the line connecting the grid to the storm drain inlet. Approaching 1: →0°, water flow is directed towards the rainwater inlet (effective catchment grid); When the value is ≥0.7, the grid cell is counted as a valid grid cell in the bus. Define the confluence coefficient λ: If λ < 0.6, it indicates that the water flow is scattered, i.e., ordinary water accumulation; If λ≥0.6, it indicates that a large area of ​​water flows towards the drainage outlet and enters the fourth level of final review; Level 4: Determination of the causes of waterlogging: like <2cm indicates good drainage and no waterlogging; like ≥2cm indicates obstructed drainage and water accumulation that cannot be discharged in time; all four conditions are met: it is determined to be a real road flooding hazard; Final flood assessment: IsFlood indicates the final flood assessment result.

8. The urban flooding monitoring method according to claim 7, characterized in that, Based on distance-Doppler characteristics, the criteria for determining the warning level are as follows: Level 1 Warning: Water depth > 15cm, or complete blockage of storm drains, or expansion of the catchment area by ≥ 50% within 10 minutes; Level 2 warning: water depth 5-15cm, or slight blockage of storm drains, or slow expansion of the catchment area.

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