KR101185731B1 - Wireless sensor network system for monitoring environment - Google Patents

Abstract

A wireless sensor network system for monitoring the environment is provided. The environmental monitoring wireless sensor network system collects ambient air environment information through an environment sensor, a sensor node that delivers the collected air environment information by a broadcasting method, and amplifies and receives the collected air environment information. And a coordinator node configured to receive the standby environment information from the relay node and the sensor node and the relay node, convert the received standby environment information into a wireless mobile communication signal, and transmit the received wireless environment communication signal to a central server. And the installation position of the relay node is determined in consideration of a free space which is not affected by an ambient signal and a two ray ground space which is affected by reflection and refraction signals. The interval at which the relay node is installed is the channel of the surrounding channel environment. Characterized in that the determination in consideration of the environment variables.

Description

Environmental monitoring wireless sensor network system {WIRELESS SENSOR NETWORK SYSTEM FOR MONITORING ENVIRONMENT}

The present invention relates to a wireless sensor network system, and more particularly to a wireless sensor network system for monitoring the environment.

A wireless sensor network means that many sensors form a network through a wireless method. In other words, wireless sensor network technology spreads sensor nodes with computing power and wireless communication ability in the natural environment or the battlefield to form an autonomous network, transmits and receives sensing information acquired from wireless networks to each other, and monitors the remote locations through the network. / A technology that can be used for control purposes.

Among wireless wireless area area (PAN) technologies, a personal wireless networking solution for short distances of up to 10 meters, ZigBee technology can combine low-power ZigBee transceivers with sensors for detecting light, pressure, temperature, and humidity to form large sensor networks. To be. Recently, Zigbee technology has emerged as a competitive short-range wireless communication technology in the field of vertical applications such as sensor networks. In particular, attempts are being made to use short-range wireless communication technology in the environmental field, which is emerging recently. In case of using the near field communication technology in the conventional environment, the air pollution degree is disclosed in real time, but it is limited to only some regions, so it is impossible to accurately know the environmental information of the point to enjoy leisure.

Therefore, technologies for wireless communication networks and sensor nodes capable of obtaining environmental information of locations corresponding to various regions and user needs in real time should be continuously studied.

According to the present invention, an installation position of a sensor node is determined by considering a free space that is not affected by an ambient signal and a two ray ground space that is affected by reflection and refraction signals. An environmental monitoring wireless sensor network system is provided to extend a communication distance.

In addition, the present invention provides an environmental monitoring wireless sensor network system that maintains the transmission efficiency between nodes of a wireless network according to the adaptation to the change in the channel environment to determine the installation position of the sensor node.

In addition, the present invention provides an environment monitoring wireless sensor network system that can grasp the air environment information of the current location and the location you want to know by providing the air environment information to the terminal node in real time.

Environmental monitoring wireless sensor network system according to an embodiment of the present invention collects the ambient air environment information through the environment sensor, the sensor node for delivering the collected air environment information in a broadcast manner, the collected air environment information Coordinator for receiving and amplifying and transmitting the received air environment information from the relay node and the sensor node and the relay node, and converts the received air environment information into a wireless mobile communication signal to transmit to the central server. A node, wherein the installation position of the sensor node and the relay node considers a free space free from interference of peripheral signals and a two ray ground space affected by reflection and refraction signals And the sensor node and the relay node are installed It is characterized in that which is determined by considering the channel environment variables around the channel environment.

The sensor node may include an information collecting unit collecting at least one information of ambient temperature, humidity, illuminance, air pollution, and vibration through the environmental sensor, and a wireless transmitting / receiving unit transmitting the collected information through short range wireless communication. Can be.

The relay node may decode a preamble including a source, a destination, a serial number, and a count number in the collected atmospheric environment information packet, and increase the count number to indicate an order in which data is hopped.

The installation position of the coordinator node is the sensor node and the relay node determined in consideration of a free space which is not affected by an ambient signal and a two ray ground space which is affected by reflection and refraction signals. It may be closer to the free space than the position of.

The interval between the sensor node and the relay node may be set in consideration of a channel environment variable, and the interval may be narrowed when the channel environment variable value is increased, and the interval may be widened when the channel environment variable value is decreased.

The coordinator code decodes a preamble including a source, a destination, a serial number, and a count number in the standby environment information packet received from the sensor node and the relay node, and compares the count number with a preset count number. It may be determined whether the sensor node and the relay node are deactivated.

The sensor node may include a simple information collecting unit which collects surrounding environment information at a lower position than the sensor node and periodically transmits information to the sensor node.

The central server may analyze the received air environment information based on a preset air environment database, and transmit state information of the air environment, which is a result of the analysis, to the terminal node.

In addition, the environmental monitoring wireless sensor network system according to another embodiment of the present invention is a two-way affected by the free space and the reflection and refraction signals are not affected by the channel environment variables and the ambient signal of the surrounding channel environment The apparatus may further include a street light in which one of the sensor node, the relay node, and the coordinator node is mounted at a position determined in consideration of a two ray ground space.

The sensor node measures and transmits temperature and humidity at a first set time interval, switches to sleep mode at a second set time interval, and measures temperature, humidity, illuminance, air pollution, and vibration at a third set time interval. Can transmit

According to the present invention, an installation position of a sensor node is determined by considering a free space that is not affected by an ambient signal and a two ray ground space that is affected by reflection and refraction signals. An environmental monitoring wireless sensor network system can be provided that extends a communication distance.

In addition, the present invention can provide an environmental monitoring wireless sensor network system that maintains the transmission efficiency between nodes of a wireless network as the installation position of the sensor node is determined in response to the change in the channel environment.

In addition, the present invention can provide an environmental monitoring wireless sensor network system that can grasp the air environment information of the current location and the location you want to know by providing the air environment information to the terminal node in real time.

1 is a view showing an environmental monitoring wireless sensor network system according to an embodiment of the present invention.
2 is a view showing a node constituting an environmental monitoring wireless sensor network system according to an embodiment of the present invention.
FIG. 3 is a graph in which a two ray ground space model is applied to determine an installation position of a node in an environmental monitoring wireless sensor network system according to an exemplary embodiment of the present invention.
4 is a graph to which a log distance model is applied to estimate an interval between nodes in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.
5 is a diagram illustrating a data packet used in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.
6 is a diagram illustrating a method for finding an inactive node in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

Referring to FIG. 1, the environmental monitoring wireless sensor network system according to an embodiment of the present invention includes sensor nodes 110, 112, 114, relay nodes 120, 122, coordinator node 130, a central server 140, and a terminal node 150, 152. It includes.

The sensor nodes 110, 112, and 114 collect surrounding air environment information through an environment sensor, and transmit the collected air environment information in a broadcasting manner. Here, the environmental sensor may include a temperature sensor, a humidity sensor, an illuminance sensor, an air pollution sensor, a vibration sensor, a gas sensor, and the like. The sensor nodes 110, 112, and 114 may transmit the collected ambient air environment information to a relay node, a coordinator node, and a terminal node in the vicinity by transmitting information in a broadcasting manner.

In addition, the sensor node (110, 112, 114) through the environmental sensor to collect information of at least one of the ambient temperature, humidity, illumination, air pollution and vibration of the ambient and wireless to transmit the collected information through a short-range wireless communication It may include a transceiver. Here, the information collecting unit may collect at least one information of ozone, carbon dioxide, and nitrogen dioxide through the gas sensor. The wireless transceiver may transmit the collected atmospheric environment information to nearby terminal nodes through short range wireless communication. The short range wireless communication may include Bluetooth, Zigbee, infrared communication (IrDA), Ultra Wide Band (UWB), Wi-Fi, and WLAN.

In addition, the sensor nodes 110, 112, and 114 may store an unpleasant index in consideration of the average temperature and humidity of each season in a database, and provide current state information to the terminal node in comparison with the collected information. In addition, the sensor nodes 110, 112, and 114 may determine the air pollution degree by measuring each air substance in Table 1, and provide current state information to the terminal node in comparison with the normal concentration and the recommended concentration. Here, the current state information may include an ozone alert, an ozone alert, and the like. Conventionally, it was possible to grasp the atmospheric environment information in a wide area unit through general news, but through the environmental monitoring wireless sensor network system according to an embodiment of the present invention can receive real-time environmental information about the narrow area where the user is located. have.

Atmospheric substance Normal concentration Recommended concentration O3 0.07 ppm 0.1 ppm  (Average hourly) CO - 25 ppm  (Average hourly) NO2 0.5 ppm  ± 0.1 0.15 ppm  (Average hourly)

In addition, the sensor nodes 110, 112, and 114 may include a simple information collecting unit that collects surrounding environment information at a lower position than the sensor node and periodically transmits information to the sensor node. When the sensor nodes 110, 112, and 114 are installed in the street light, the sensor nodes 110, 112, and 114 may be installed at positions accessible to the user, and may transmit the user's status information when the user is in an emergency situation. In addition, the sensor nodes 110, 112, and 114 may collect the surrounding environment information through a plurality of simple information collectors having different positions to increase the accuracy of the atmospheric environment information.

In addition, the sensor nodes 110, 112, and 114 measure and transmit temperature and humidity in a first set time period, switch to a sleep mode in a second set time period, and (consider power consumption during a time when no people are present). Temperature, humidity, light intensity, air pollution and vibration can be measured and transmitted over time intervals. The first set time period may be an evening time when there are not many users. The second set time period may be a dawn time with few users. The third set time period may be the morning and afternoon time with the most users. That is, the sensor nodes 110, 112, and 114 may adjust the type of atmospheric environment information collected in response to the time required for user information in consideration of power consumption.

In addition, the sensor nodes 110, 112, 114 may include display means such as LEDs or LCDs. That is, the sensor nodes 110, 112, and 114 may display the collected atmospheric environment information through the display means. For example, the sensor nodes 110, 112, and 114 may display whether the concentration is normal or dangerous, compared to the current concentration of air, carbon dioxide, and nitrogen dioxide, and the preset reference concentration.

The relay nodes 120 and 122 receive the collected atmospheric environment information and amplify and transmit the amplified broadcast information. The relay nodes 120 and 122 amplify the atmospheric environment information received from the sensor nodes 110, 112, and 114 and transmit the amplified environment information to other relay nodes, coordinator nodes, and terminal nodes. That is, the relay nodes 120 and 122 serve to reliably transmit the information collected by the sensor nodes 110, 112, and 114 to the coordinator node and the terminal node.

In addition, the relay nodes 120 and 122 decode a preamble including a source, a destination, a serial number, and a count number from the collected atmospheric environment information packet, and increase the count number to indicate an order in which data is hopped. Can be. The information collected by the sensor nodes 110, 112, and 114 is transmitted in the form of a data packet. The head of the packet indicates a source indicating the information of the node that initially transmits the information, a destination indicating the information of the node to receive the information from the source, and the information. It may include a unique serial number of the node to transmit and receive, the count number indicating the hopping order when data is transmitted in a hopping manner. That is, the relay nodes 120 and 122 may receive the standby environment information packet to increase the count number to indicate the order of data hopping.

The coordinator node 130 receives air environment information from the sensor nodes 110, 112, 114, and relay nodes 120, 122, converts the received air environment information into a wireless mobile communication signal, and transmits the received air environment information to the central server. The coordinator node 130 collects the air environment information and transmits the air environment information to the central server so that the air condition information for each region can be analyzed in a predetermined total regional unit.

The wireless mobile communication signal may include all mobile communication signals for relaying wireless data such as WCDMA, GSM, TDMA, LTE, and LTE-A.

The installation positions of the sensor nodes 110, 112, 114, the relay nodes 120, 122, and the coordinator node 130 are free spaces that are not affected by surrounding signals and two-ray ground areas that are affected by reflection and refraction signals. ground space). The sensor nodes 110, 112, 114, the relay nodes 120, 122, and the coordinator node 130 constituting the environmental monitoring wireless sensor network system according to an exemplary embodiment of the present invention are not installed at arbitrary positions, but the two-ray ground area model ( This is determined using a two ray ground space model. The method of determining the installation position in Figure 3 will be described in more detail.

In addition, the interval at which the sensor nodes 110, 112, 114, the relay nodes 120, 122, and the coordinator node 130 are installed is determined in consideration of channel environment variables of the surrounding channel environment. The sensor nodes 110, 112, 114, relay nodes 120, 122, and coordinator node 130 constituting the environmental monitoring wireless sensor network system according to an embodiment of the present invention are configured with a log-distance model for a communication channel environment. Can be used to determine the maximum communicable distance. A method of determining the distance between nodes in FIG. 4 will be described in more detail.

In addition, the installation position of the coordinator node 130 is a sensor node determined in consideration of a free space that is not affected by the ambient signal and a two ray ground space that is affected by the reflection and refraction signals ( It may be closer to the free space than the locations of 110, 112, 114 and relay nodes 120, 122. By installing the coordinator node 130 close to a free space, it is possible to accurately and stably receive atmospheric environment information transmitted from the sensor nodes 110, 112, 114 and the relay nodes 120, 122 without being affected by surrounding signals. have.

The central server 140 analyzes the received air environment information based on a preset air environment database, and transmits the state information of the air environment, which is a result of the analysis, to the terminal nodes 150 and 152. In this case, the atmospheric environment database may include seasonal, quarterly, monthly, hourly temperature, humidity, illumination, ozone amount, carbon dioxide amount, nitrogen dioxide amount, and frequency according to an earthquake. The central server 140 may generate wide-area atmospheric environment information by analyzing the atmospheric environment information of each region received from the coordinator node 130 for each region in a larger unit, and transmit the wide-area atmospheric environment information to the terminal node. .

The terminal nodes 150 and 152 are terminals capable of requesting air environment information and receiving air environment information corresponding to the request in the environment monitoring wireless sensor network system according to an embodiment of the present invention. For example, the terminal nodes 150 and 152 may be mobile phones, smart phones, PDAs, notebook computers, PMPs, and MP3s.

In addition, the environmental monitoring wireless sensor network system according to an embodiment of the present invention is a free space that is not affected by channel environment variables and ambient signals of the surrounding channel environment and two-ray ground affected by reflection and refraction signals The lighting apparatus may further include a street light in which one of the sensor nodes 110, 112, 114, the relay nodes 120, 122, and the coordinator node 130 is mounted at a location determined in consideration of a two ray ground space. The street light may collect the air environment information by mounting the sensor nodes 110, 112, and 114 to transmit the current air environment information to the user in real time.

2 is a view showing a node constituting an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

Environmental monitoring wireless sensor network system according to an embodiment of the present invention includes a sensor node, a relay node, a coordinator node and a terminal node. The sensor node may include an information collecting unit collecting air environment information around the sensor node and a wireless transmitting / receiving unit transmitting the collected air environment information to the relay node and the terminal node in a broadcasting manner. The relay node receives the atmospheric environment information from the sensor node, examines whether the information is in error, amplifies the signal strength, and delivers the atmospheric environment information to the coordinator node and the terminal node. The coordinator node collects the atmospheric environment information from the sensor node and the relay node and transmits it to the central server. That is, the coordinator node may be connected to the central control server to manage the entire node. The terminal node may request the standby environment information from the sensor node and the relay node, and receive the standby environment information corresponding to the request in a broadcast manner.

FIG. 3 is a graph in which a two ray ground space model is applied to determine an installation position of a node in an environmental monitoring wireless sensor network system according to an exemplary embodiment of the present invention.

는 송신 노드와 수신 노드 사이의 거리,

는 송신 노드의 높이,

는 수신 노드의 높이,

는 전송 신호의 파장을 의미한다. 도 3에서는 주파수 2.4㎓를 사용하였고, 송신 노드와 수신 노드 사이의 거리를 200m, 송신 노드와 수신 노드의 높이를 같게 하여 계산하였다. 도 3을 참조하면 자유 영역(free space)에서 신호를 송수신하기 위해서는 3.5m 이상의 높이에 노드가 위치하면 된다. 따라서, 노드를 가로등에 탑재하는 경우에는 3.5m 에서 4m 높이에 설치하는 것을 고려할 수 있다.In the environmental monitoring wireless sensor network system according to an embodiment of the present invention, the installation position of the node is a two ray ground space and a line of sight (LOS) environment considering an area where signals are reflected and refracted. It is determined taking into account the free space of. Equation 1 applies a two ray ground space model. here

Is the distance between the sending node and the receiving node,

Is the height of the sending node,

Is the height of the receiving node,

Is the wavelength of the transmission signal. In FIG. 3, a frequency of 2.4 GHz was used, and the distance between the transmitting node and the receiving node was calculated by 200 m and the heights of the transmitting node and the receiving node were the same. Referring to FIG. 3, a node may be located at a height of 3.5m or more in order to transmit and receive a signal in a free space. Therefore, when the node is mounted on the street light, it may be considered to install at a height of 3.5m to 4m.

[Equation 1]

4 is a graph to which a log distance model is applied to estimate an interval between nodes in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

The log-distance model is a model of the strength of a received signal according to a distance in consideration of a channel environment. Referring to Table 2, variables of a channel environment (Path Loss Exponent) are shown in various environments. The variable value of the channel environment is used as the n value in Equation 2.

Environment Channel environment variables Environment Channel environment variables Free zone 2 Visible Path Area Inside Building 1.6 to 1.8 Inner City Propagation Zone 2.7 to 3.5 Congestion path area inside the building 4 to 6 Semi-center propagation area 3 to 5 Congestion Path Area inside the Factory 2 to 3

는 기준거리이고,

는 노드 간의 거리이며, n 은 표 2의 채널 환경 변수(Path Loss Exponent) 값이다. 도 4에서는 각 노드간에 사용되는 주파수는 2.4㎓, 송신 전력은 7dBm, 송신 안테나의 이득은 3dBi, 수신 안테나의 이득은 6dBi, 대역폭은 2㎒, 시스템에 요구되는 SNR_min은 2dBm, 기준거리는 1m 에서 수학식 2를 계산하였다. 도 4는 거리에 따른 수신 전력을 나타낸 도면인데, n 값에 따라 그 기울기가 다르다. 채널 환경 변수 n 값은 표 2에서 센서 노드가 가장 많이 활용될 수 있는 준도심 전파영역(Shadow urban cellular radio)을 적용하여 3에서 5의 범위로 설정하였다. n 값이 3에서 5인 범위에서 민감도(Sensitivity) 가 -91dBm인 경우에 노드 간의 거리는 40m 에서 400m까지 정보의 송수신이 가능하다. 따라서, 채널 환경이 준도심 전파영역(Shadow urban cellular radio)인 경우에 200m를 기준으로 노드 간의 거리를 설정하고, 투 레이 그라운드 영역 모델(two ray ground space model)을 이용하여 노드의 높이를 결정할 수 있다.In the environmental monitoring wireless sensor network system according to an embodiment of the present invention, the interval between each node may vary depending on the surrounding channel environment of the node that sends and receives information. The influence of the surrounding channel environment on the distance between nodes is reflected in Equation 2 using a log-distance model. here

Is the reference distance,

Is a distance between nodes, and n is a value of a channel environment variable (Path Loss Exponent) of Table 2. In Figure 4, the frequency used between each node is 2.4 GHz, the transmission power is 7dBm, the gain of the transmitting antenna is 3dBi, the gain of the receiving antenna is 6dBi, the bandwidth is 2MHz, the SNR _min required by the system is 2dBm, the reference distance is 1m Equation 2 was calculated. 4 is a diagram illustrating received power according to a distance, and its slope varies according to n values. The channel environment variable n is set in the range of 3 to 5 by applying a shadow urban cellular radio in which the sensor node is most utilized in Table 2. If the sensitivity is -91dBm in the range of n to 3 to 5, the distance between nodes can transmit and receive information from 40m to 400m. Therefore, when the channel environment is a shadow urban cellular radio, the distance between nodes may be set based on 200 m, and the height of the nodes may be determined using a two ray ground space model. have.

&Quot; (2) "

In addition, in the environmental monitoring wireless sensor network system according to an embodiment of the present invention, the interval between the installation of the sensor node and the relay node becomes smaller when the channel environment variable value is increased in consideration of the channel environment variable. As the width becomes smaller, the spacing between nodes can be widened. In other words, increasing the value of the channel environment variable means that the transmission efficiency becomes worse. Therefore, in order to maintain the transmission efficiency, the distance between nodes must be closer, and a smaller value of the channel environment variable means that the signal transmission efficiency becomes better. The distance between the nodes can be far from this maintained range.

In addition, the sensor node and the relay node may adjust the transmission power in consideration of the channel environment variable value. When data is transmitted between the nodes, the transmitting node may transmit data to the receiving node at the existing power, and transmit data by adjusting the transmission power by using Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) values. .

5 is a diagram illustrating a data packet used in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

Referring to FIG. 5, in the environmental monitoring wireless sensor network system according to an embodiment of the present invention, a preamble of a data packet indicates a source indicating information of a node that initially transmits information, and information of a node to receive information from the source. It may be defined as a destination indicating a, a unique serial number of each node that transmits and receives information, and a count number indicating a hopping order when data is transmitted in a hopping manner. Here, the count number may indicate the order of data hopping by increasing the number of counts by receiving nodes decode the preamble of the packet between nodes set to the minimum transmission distance when data is transmitted in a hopping manner.

6 is a diagram illustrating a method for finding an inactive node in an environmental monitoring wireless sensor network system according to an embodiment of the present invention.

The coordinator code decodes a preamble including a source, a destination, a serial number, and a count number in a standby environment information packet received from a sensor node and a relay node, and compares the count number with a preset count number. It may be determined whether the relay node is deactivated. The node receiving the information decodes the preamble of the data packet to detect the count number, and compares the count number based on the source and destination set in each node with the detected count number of the node generated during the transmission process. It can be determined whether to deactivate. In this case, the information is transmitted by storing the serial number of the node that has transmitted or received the information in a data packet or by displaying whether or not to receive the hello message in the packet when receiving the hello message from the node that should receive the information through the hello message. It may be determined whether the node is deactivated.

Referring to FIG. 6, in case of transmitting information from node A to node H, the source may be A, the destination may be H, and the relay node may be B to G in the middle. If the shortest transmission path from node A to node H is preconfigured as A → C → D → E → F → H, the count number of the data packet at node A is 0 and increases by one each time it passes through node H. At the node, the count number must be five. However, if the count number is not 5 in the H node, it means that the relay node is deactivated or information is transmitted through an additional relay node that is not the shortest transmission path. Even if the count number is 5, it can pass through a node other than the shortest transmission path, but each node receives information from the node of the shortest transmission path by storing serial numbers of its own node and the node in the shortest transmission path. In other words, by transmitting information to the node of the shortest transmission path, it is possible to avoid leaving the shortest transmission path.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

Claims (10)

In the environmental monitoring wireless sensor network system,
A sensor node that collects ambient air environment information through an environmental sensor and delivers the collected air environment information in a broadcasting manner;
A relay node receiving the collected atmospheric environment information and amplifying and transmitting the amplified broadcast information; And
And a coordinator node configured to receive the air environment information from the sensor node and the relay node, convert the received air environment information into a wireless mobile communication signal, and transmit the received air environment information to a central server.
The distance between the sensor node and the relay node is determined based on Equation 1 considering the channel environment variable of the surrounding channel environment, wherein,

Is distance between sensor node and relay node, n is channel environment variable,

Is the reference distance,

The

Path loss at,

The

The path loss at
[Equation 1]

The height of the sensor node and the height of the relay node is determined based on Equation 2, wherein,

Is the distance between the sensor node and the relay node,

Is the height of the sensor node,

Is the height of the relay node,

Is the wavelength of the transmitted signal
&Quot; (2) "

Environmental monitoring wireless sensor network system. The method of claim 1,
The sensor node is
An information collector configured to collect at least one of ambient temperature, humidity, illuminance, air pollution, and vibration through the environmental sensor; And
A wireless transceiver for transmitting the collected information through short range wireless communication
Environmental monitoring wireless sensor network system comprising a. The method of claim 1,
And the relay node decodes a preamble including a source, a destination, a serial number, and a count number in the collected atmospheric environment information packet, and increases the count number to indicate an order in which data is hopped. The method of claim 1,
The installation position of the coordinator node is the sensor node and the relay node determined in consideration of a free space which is not affected by an ambient signal and a two ray ground space which is affected by reflection and refraction signals. And an environmental monitoring wireless sensor network system closer to the free space than to the location of. The method of claim 1,
The interval between the sensor node and the relay node is set in consideration of the channel environment variable, the interval is narrowed when the channel environment variable value is increased, the interval is widened when the channel environment variable value is smaller. Network system. Claim 6 has been abandoned due to the setting registration fee. The method of claim 1,
The coordinator code decodes a preamble including a source, a destination, a serial number, and a count number in the standby environment information packet received from the sensor node and the relay node, and compares the count number with a preset count number. An environmental monitoring wireless sensor network system for determining whether a sensor node and the relay node are deactivated. Claim 7 was abandoned upon payment of a set-up fee. The method of claim 1,
The sensor node is
Environmental monitoring wireless sensor network system comprising a simple information collecting unit for collecting the surrounding environment information at a lower position than the sensor node, and periodically transmits information to the sensor node. Claim 8 was abandoned when the registration fee was paid. The method of claim 1,
The central server analyzes the received air environment information based on a preset air environment database, and transmits state information of the air environment as a result of the analysis to a terminal node. Claim 9 has been abandoned due to the setting registration fee. The method of claim 1,
The sensor node at a position determined in consideration of a channel environment variable of a surrounding channel environment and a free space free from interference of the surrounding signal and a two ray ground space affected by reflection and refraction signals, Street light mounted with one of the relay node and the coordinator node
Environmental monitoring wireless sensor network system further comprising. Claim 10 has been abandoned due to the setting registration fee. The method of claim 1,
The sensor node is
Measure and transmit the temperature and humidity in the first set time period,
Enters the sleep mode in the second set time period,
Environmental monitoring wireless sensor network system, characterized in that for measuring the temperature, humidity, illumination, air pollution and vibration in the third set time period.

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