KR20120140117A - Usn based low power emergency communication system - Google Patents

Abstract

PURPOSE: A low power disaster alarm system based on USN is provided to automatically detect a disaster occurrence and be implemented with a low power sensor module for the resolution of a power problem, thereby preparing for a disaster on the mountain or the wild. CONSTITUTION: A low power disaster alarm system based on USN includes plural sensor nodes, plural routers, a boundary router, and a CDMA(Code Division Multiple Access) repeater. The plural sensor nodes measure a disaster in a prescribed area. The plural routers receive the measured values of the sensor nodes. The plural routers transmit the measured values of the sensor nodes to the boundary router. The boundary router receives data from the routers. The boundary router transmits data to the CDMA repeater. [Reference numerals] (AA) Sensor node; (BB) Router; (CC) Boundary router; (DD) CDMA relay; (EE) CDMA network; (F1) Area 1; (F2) Area 2; (F3) Area 3; (F4) Area n

Description

USS based low power emergency communication system

The present invention relates to a disaster alert system, and more particularly, to a low power disaster alert system and method based on a Ubiquitous Sensor Network (USN). Low-power sensor by battery in areas where power supply is not easy, such as disaster warning method by USN environment that can accurately and quickly identify disaster location, spreading path and spreading speed in case of disaster such as earthquake and wildfire It relates to how to operate a node.

Immediately after the Daegu subway disaster in 2003, the construction of disaster safety communication network and disaster warning system began to be discussed in Korea. No one can deny that a disaster alert system is essential to respond quickly to natural disasters or national security emergencies. Tetra, Wibro, etc. were considered as emergency communication networks for disaster alert systems, but only a lot of controversy arose over pros and cons and monopoly issues. As a candidate, Tetra has problems with standard delays, Motorola's monopoly, and its high dependence on a company.As seen in the last earthquake disaster in Japan, the existing disaster warning system has no idea of the magnitude of the disaster. Information could not be provided and communications would be disrupted when the power supply network was destroyed.

Accurate and rapid identification of disaster location, spreading path and spread rate during disasters such as earthquake and forest fire is very important for early response of disasters, and it is not easy to supply power such as mountainous areas. The operation of low power sensor nodes by batteries in the area is a very important factor for the stable and reliable operation of the system.

Conventional technologies of the disaster alert system include a system based on WiBro of FIG. 1 as shown in Patent Document 1, and a system using the Internet as shown in FIG. 2 as shown in Patent Document 2, which is based on USN. The patent documents of FIGS. 3 to 5 have been proposed.

1 is a public safety disaster relief system using a conventional WiMAX and Wi-Fi communication network. 1 relates to transmission and reception between a mobile transceiver device and a fire disaster prevention center system carried by a rescue worker using WiMAX and Wi-Fi communication networks, which are based on the present invention. At the same time, there is no solution to the prediction of speed. In addition, Patent Literature 1 requires a fire brigade to install a radio repeater in a disaster area at the time of rescue, and there is a power supply problem.

2 is related to the disaster prevention system using the Internet and the wireless communication network proposed in Patent Document 2, using a system for monitoring the state of the fire sensor and sensor including a heat detector or smoke detector and the Internet or CDMA / GSM communication network It is characterized by a system for transmitting and receiving. Patent Document 2 also can not collect any information on the size of the disaster, such as Patent Document 1, and does not present any solution to the power supply problem.

3 to 5 are prior arts for detecting disasters and the like using USN by a wide range of sensor nodes in order to overcome the limitations of Patent Document 1 and Patent Document 2. FIG.

3 is a disaster management system using USN proposed in Patent Document 3. In the event of a disaster, the sensor node detects this and notifies the danger area to the disaster occurrence area through an actuator such as a siren or notifies the risk to the management system through a wired / wireless network. However, Patent Document 3 also does not present a solution to the power problem, and also does not provide information on the disaster, such as the problem of automatic detection of the position of the detected sensor.

4 is to solve the information collection member for the disaster proposed in Patent Document 4, characterized in that to transmit forest fire data through the unmanned forest fire monitoring system and generate forest fire progress prediction data. However, there is a need for expensive equipment such as a wildfire surveillance camera, there is a problem with the power supply required for installation of the camera and sensor node.

5 includes a control server that detects and analyzes harmful environment information through the USN-based multiple sensor module proposed in Patent Document 5 to set a warning level and notify a dangerous situation. However, there is no specific description of the power problem and the location of the multiple sensor module.

As described above, the prior art literature on the disaster warning system lacks information on disasters such as the magnitude of disaster, spreading rate, and spreading path in the event of a disaster, and does not present measures for power consumption. It is not intended to be used at all.

1. Korea Patent Registration Publication 10-0788886 2. Korean Patent Registration Publication 10-0705661 3. Korea Patent Registration Publication 10-0826539 4. Korea Patent Registration Publication 10-0900937 5. Korean Patent Publication No. 10-2010-0118928

The present invention has been made to solve the problems of the prior art as described above, and to provide a disaster system configuration diagram and algorithm for accurately measuring the occurrence of the disaster and the occurrence location, the spread path, the spread rate for the first object.

A second object of the present invention is to provide a low power algorithm of a sensor node through a method of operating a communication network comprising a sensor node for measuring a disaster and a router for relay communication.

The USN-based disaster alert system according to the present invention for solving the above problems, a plurality of sensor nodes for disaster measurement of a predetermined area, a plurality of routers for receiving the measured values of the sensor node to transmit to the border router It includes a border router and a CDMA repeater for receiving data from the router and transmitting to the CDMA repeater.

As an embodiment of the present invention, the border router corresponds to a wide area location, the router corresponds to a local location in a wide area, each sensor node is configured to indicate a detailed location, the sensor node is an environmental sensor unit, a disaster occurrence detection unit And a disaster information processing unit and a Zigbee transmitter.

As an embodiment of the present invention, the sensor node operates only the environmental sensor and the disaster detection unit when a disaster does not occur, and turns on the power switch of the disaster information processing unit and the transmitter when the disaster is detected. The sensor node includes a storage battery which is charged by solar cells or wind power generation.

In one embodiment of the present invention, the router receives the measurement data from the sensor node and converts the RF data of the GFSK type to the boundary router.

In one embodiment of the present invention, in a method of operating a USN-based disaster alert system consisting of a plurality of sensor nodes, routers, border routers and CDMA repeaters,

Receiving disaster occurrence information from an environmental sensor unit of the sensor node and determining whether or not a disaster occurs in the disaster detection unit;

Turning on a power switch to apply power to the disaster information processing and transmission unit when the disaster occurrence detection unit determines that a disaster has occurred;

Transmitting the disaster information to the router or border router through the Zigbee transmitter of the sensor node;

Receiving, at the router, disaster information from the sensor node, converting the disaster information into a GFSK, and transmitting it to the boundary router;

Receiving disaster information from the sensor node or the router at the boundary router and transmitting the disaster information to the CDMA repeater; And

And converting the disaster information received through the GFSK receiver in the CDMA repeater into a CDMA signal and transmitting the same to the central control center.

In one embodiment of the present invention, in the disaster prediction method in the USN-based disaster alert system,

Receiving a disaster occurrence signal at a time Tk from a specific sensor node Sij among the plurality of sensor nodes;

Receiving a disaster occurrence signal from Sab and not the sensor node at time Tl;

Obtaining a distance d and a diffusion path between the sensor nodes using node information of the sensor nodes Sij and Sab receiving the disaster occurrence signal;

Obtaining a disaster spread rate V as V = d / (Tk − Tl) using the disaster occurrence signal reception time Tk and Tl; And

And notifying or displaying the spreading path and the spreading speed, and further comprising calculating a disaster area by using the number of sensor nodes at which an initial disaster occurrence signal is detected.

In one embodiment of the present invention, in the sensor node of the USN-based disaster alert system,

The sensor node is an environmental sensor unit for sensing the environment;

 Disaster occurrence detection unit for determining whether or not a disaster occurred from the measured value of the environmental sensor;

A disaster information processor including an analog-to-digital converter, a GPS position finder, and a microprocessor for transmitting signal information to a router when it is determined that a disaster occurs;

A Zigbee transmitter for transmitting to a router; And

 It is configured to include a power switch and a storage battery,

When a disaster does not occur, only the environmental sensor and the disaster detection unit operate. When a disaster occurs, the power is applied to the power switch of the disaster information processor and the Zigbee transmitter. It is characterized in that the transmission distance is about 1.5Km by adding RF Amp to have a transmission power of 13dBm.

The present invention is to solve the problem that the prior art is difficult to obtain information on the magnitude of the disaster, the spreading rate, the spreading path, etc., and difficult to build a system for disasters in places where power supply is difficult, and automatically detects the occurrence of a disaster Disaster location, spreading path, and spreading speed can be measured accurately, and low-power sensor module in sensor node for solving power problems can be prepared for mountain and remote disasters.

The recurrence alarm system according to the present invention makes it possible to construct and manage a systematic disaster management network by systematically assigning and managing addresses when adding a sensor node by simplifying address system management, and uses an unlicensed frequency band of 400 MHz and a GFSK communication method. By doing so, it can be used without a separate notification or permission, and can minimize radio interference caused by obstacles.

1 is a public safety disaster relief network system using WiMAX and Wi-Fi network in the prior art and a method of operation.
2 is a related art disaster prevention system using the Internet and a wireless communication network.
3 is a schematic diagram of a disaster management system using USN in the related art.
4 is a diagram illustrating a configuration of an unmanned wildfire monitoring system using USN and RF in the prior art.
5 is a configuration of a hazardous environment information detection system using a USN-based complex multi-sensor module according to the prior art.
6 is an overall system diagram of the USN-based low power disaster alert system of the present invention.
7 is a diagram illustrating a disaster prediction algorithm performed in the USN-based disaster alert system of the present invention.
8 is a USN sensor node block diagram of the present invention.
9 is a router block diagram of the present invention.
10 is a border router block diagram of the present invention.
11 is a CDMA repeater block diagram of the present invention.
12 is a conceptual diagram of a sensor node address management scheme using a boundary router according to the present invention.

Hereinafter, a disaster alert system according to the present invention will be described. Disaster alert systems must continuously monitor a wide range of areas without time constraints and must be able to provide information on the magnitude, spread rate and route of the disaster for critical early response in the event of a disaster.

The present invention has established a disaster alert system based on USN to provide such a disaster alert system. USN-based sensor nodes enable disaster monitoring in a wide range of locations. In addition, a disaster prediction algorithm using a sensor node is disclosed to enable accurate information on disaster size, spread rate, and path for initial response.

In addition, the present invention discloses a low power structure of a sensor node through a method of operating a communication network including a sensor node and a router for relay communication.

Figure 6 shows the overall system configuration of the present invention, the area shown in Figure 6 has a range of about 3Km in diameter, a number of sensor nodes for disaster measurement and about four routers for the transmission of measurement values (router) ) And a border router for transmitting the data received from the router to the CDMA repeater, and a CDMA repeater for transmitting the measurement data collected from the border router to the control center through the CDMA network. Each sensor node has a built-in GPS locator, and when a disaster occurs, the position of the sensor that detected the first disaster becomes the position of the first disaster, and the disaster spread path is measured in the order of the second sensor node and the third sensor node. In this case, the initial disaster detection time of the sensor nodes is the spreading speed.

The disaster prediction algorithm is shown in FIG. The example shows how the disaster spread path can be measured from the sensor node detection sequence.

In an embodiment, when there are N x M sensor nodes in the first boundary router, the sensor nodes in each i row and j column may be represented by Sij. Before a disaster, each sensor node is powered only by the environmental sensor and the disaster detection unit, but when a disaster is detected, the power switch is turned on and the sensing information is transmitted to the router through the Zigbee transmitter. In this case, the location information of the GPS node may be transmitted together with only the ij address information of the sensor node together with the sensing information. The sensor node's address, information arrival time, and location information collected by the central control center via routers and border routers allow the control center to grasp the magnitude, spreading speed, and path of the disaster. That is, if the disaster detection information at Sij + 1 is received after the T ms time after the disaster detection information of the sensor node Sij, the diffusion rate V = (distance between Sij and Sij + 1) / T can be obtained and the diffusion path is Sij. Can be predicted from the layout of Sij + 1 and the GPS information of the sensor nodes. In addition, if disaster occurrence information is collected from k sensors at the time of initial disaster detection, the magnitude of the initial disaster is also predictable according to the magnitude of k. Although not shown in the embodiment, the predicted disaster information may be notified to the administrator display or wired / wireless.

FIG. 8 is a block diagram of a sensor node, in which sensors such as fire, earthquake, and airflow, which are kinds of disasters, are connected in a multiplex to sequentially select and measure the connected sensors one by one, The measured data converted into values transmits the measured value at a predetermined period in the microprocessor. For example, once a disaster does not occur, the measured data is measured once every 10 seconds in a zigbee. The transmitter can transmit to the router.

When a disaster does not occur for the low power algorithm design of the sensor node, only the environmental sensor and the disaster occurrence detection unit are operated in the low power mode in FIG. 8, and the measured value is measured above the set value in the disaster occurrence detection unit. In this case, a signal is supplied to a power switch for applying power to the disaster information processing and transmission unit of FIG. 8 so that the measured values can be urgently transmitted.

In areas where the sensor node is installed in a mountain or remote area where it is difficult to supply commercial power, a battery such as a battery is used as well as a battery that is charged by renewable energy such as solar cells or wind power.

Zigbee transmitter adds RF Amp to have 13dBm transmit power and transmit distance is about 1.5Km. If the router is located in four locations at 90 degrees as shown in Figure 6, the diameter of the transmission zone is 3km. Routers use commercial power because they require continuous data transfer.

In the exemplary embodiment of FIG. 8, the GPS module is mounted on the sensor node. However, even when a GPS module error occurs or there is no GPS configuration, the spreading speed and path of the disaster may be predicted by a disaster prediction algorithm as shown in FIG. 7.

9 shows a block diagram of a router of the present invention. The router receives the measurement data from the sensor node and converts the measured data into a RF signal in the form of Gaussian Frequency Shift Keying (GFSK) and transmits it to a border router. GFSK's RF Power is designed to have a power output of 37dBm, allowing transmission distances within 15km.

FIG. 10 shows a block diagram of a border router and simultaneously transmits measurement data received from the router to the CDMA repeater along with relay transmission of the measurement data received from the sensor node.

11 shows a block diagram of a CDMA repeater and converts measured values received from a border router into a CDMA signal and transmits data to the control center.

By using the boundary router, which is a feature of the present invention, the following advantages are obtained. First is the simplicity of the address management system. For example, if tens of millions of sensor nodes installed nationwide have different addresses, they must have millions of address capacities for address assignment, which requires tens of bytes of additional data for address transmission. The waste of transmission energy and the rapid increase of traffic may prevent reliable data transmission due to data collision.

As shown in FIG. 12, when the address management system is hierarchically managed by a border router, a router, and a sensor node, the address of the sensor node is managed by a router. The address of sensor nodes can be assigned sequentially, and other routers can also assign the address of sensor nodes belonging to their area from 1 first. In transmission, data length and traffic volume can be reduced.

The second advantage is that the location of each border router, router and sensor node can be known. As shown in Figure 12, the address of the border router (border router) indicates a wide area location as an example of forest fire monitoring border router-1 may be designated as 'Chungcheongnam-do', router-1 is 'Gyeryongsan', the sensor node -1 is to know the actual location intuitively with each address like 'Mountain 5-1', so it is possible to quickly respond by identifying the approximate disaster location only by the address of the disaster occurrence sensor node. Therefore, it is possible to construct systematic disaster management network by systematically assigning and managing addresses when adding sensor nodes.

In addition, by using GFSK, which is a low frequency of 400MHz band, it minimizes radio interference caused by obstacles and can be used without additional notification or permission since it is an unlicensed frequency band.

The scope of the present invention is not limited to the above-described embodiments of the present invention, and various modifications and improvements by those skilled in the art to which the present invention pertains based on the basic technical idea of the present invention correspond to various modifications and configurations of the embodiments. A program that realizes possible means or functions or that can be implemented through a recording medium on which the program is recorded is also within the scope of the present invention.

Claims (10)

In the USN-based disaster alert system,
A plurality of sensor nodes for disaster measurement of a predetermined area;
A plurality of routers for receiving the measured values of the sensor nodes and transmitting the measured values to a border router;
A border router receiving data from the router and transmitting the data to a CDMA repeater; And
USN-based disaster alert system with a CDMA repeater. The method of claim 1,
The sensor node USN-based disaster alert system, characterized in that it comprises an environmental sensor unit, disaster occurrence detection unit, disaster information processing unit and transmitter. The method of claim 2,
The sensor node operates only the environmental sensor and the disaster detection unit when a disaster does not occur, and turns on the power switch of the disaster information processing unit and the transmitter when the disaster is detected and applies power. USN-based disaster alert system. The method of claim 1,
The sensor node USN-based disaster alert system, characterized in that it comprises a battery which is charged by solar or wind power generation. The method of claim 1,
The router receives the measurement data from the sensor node USN-based disaster alert system, characterized in that for converting the RF signal of the GFSK type transmission to the boundary router. In the operating method of the USN-based disaster alert system consisting of a plurality of sensor nodes, routers, border routers and CDMA repeaters,
Receiving disaster occurrence information from an environmental sensor unit of the sensor node and determining whether or not a disaster occurs in the disaster detection unit;
Turning on a power switch to apply power to the disaster information processing and transmission unit when the disaster occurrence detection unit determines that a disaster has occurred;
Transmitting the disaster information to the router or border router through the Zigbee transmitter of the sensor node;
Receiving, at the router, disaster information from the sensor node, converting the disaster information into a GFSK, and transmitting it to the boundary router;
Receiving disaster information from the sensor node or the router at the boundary router and transmitting the disaster information to the CDMA repeater; And
A method of operating a USN-based disaster alert system comprising converting a disaster information received through a GFSK receiver at a CDMA repeater into a CDMA signal and transmitting it to a central control center. In the disaster prediction method in the USN-based disaster alert system,
Receiving a disaster occurrence signal at a time Tk from a specific sensor node Sij among the plurality of sensor nodes;
Receiving a disaster occurrence signal from Sab and not the sensor node at time Tl;
Obtaining a distance d and a diffusion path between the sensor nodes using node information of the sensor nodes Sij and Sab receiving the disaster occurrence signal;
Obtaining a disaster spread rate V as V = d / (Tk − Tl) using the disaster occurrence signal reception time Tk and Tl; And
Notifying or displaying the spreading path and the spreading rate. The method of claim 7, wherein
Disaster prediction method in the USN-based disaster warning system further comprising the step of calculating the disaster area area by using the number of sensor nodes for which the initial disaster signal is detected. In the sensor node of the USN-based disaster alert system,
The sensor node is an environmental sensor unit for sensing the environment;
Disaster occurrence detection unit for determining whether or not a disaster occurred from the measured value of the environmental sensor;
A disaster information processor including an analog-to-digital converter, a GPS position finder, and a microprocessor for transmitting signal information to a router when it is determined that a disaster occurs;
A Zigbee transmitter for transmitting to a router; And
It is configured to include a power switch and a storage battery,
Sensor node of the USN-based disaster alert system, characterized in that only the environmental sensor and the disaster detection unit operates when a disaster does not occur. 10. The sensor node of claim 9, wherein the Zigbee transmitter adds an RF Amp so that the transmission distance is at least 1.5 km with a transmission power of 13 dBm.

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