KR100705537B1 - Probabilistic determination method of sensor activation for wireless sensor networks - Google Patents

Abstract

The present invention relates to a method for determining probability-based sensor activation in a wireless sensor network. The method for determining probability-based sensor activation in a wireless sensor network is a method for determining a sensor node activation in a wireless sensor network. Set to Listen and obtaining information of neighboring sensor nodes through wireless data communication with neighboring sensor nodes, (2) sensing radius (r) of sensor node and area (U) of sensor field. Calculating a minimum number of active nodes (N _CON ) that can guarantee coverage and connectorivity of the entire network using the minimum number of active nodes (N _CON ) using the minimum number of active nodes (N _CON ). Computing the average number of neighboring sensor nodes (MN _CON ) that can guarantee the coverage and connector connectivity of the network at the sensor node, (4) The average number of neighboring sensor nodes (MN) Calculating an active probability (P _Active ) of the sensor node using _CON ), and (5) determining whether the sensor node is active using the active probability (P _Active ). Probability-based sensor activation determination in a network.

According to the present invention, it is possible to extend the life of the sensor network by controlling whether the sensor node is activated or not according to a certain probability while ensuring coverage and connector connectivity of the network. As the state of all sensor nodes is determined based on the probabilities of adaptive adaptation to information, it is possible to control the flexible sensor nodes, thereby ensuring the performance of the network in various environments.

Wireless sensor, sensor network, sensor activation method, ubiquitous, sensor node

Description

Probabilistic determination method of sensor activation for wireless sensor networks

1 is an exemplary configuration diagram of a wireless sensor network.

2A and 2B are exemplary diagrams illustrating a model for partition prediction.

3A, 3B, and 3C are exemplary views showing regions to be connected according to the number of connected nodes.

4 is a round configuration diagram of a wireless sensor network.

5 is a sensor node state transition diagram according to an embodiment of the present invention.

6 is a flow chart showing a sensor node activation determination process according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100: sensing field 102: sink node

104, 106, 108, 110: sensor node 120: sensor node

The present invention relates to a method for determining an operational state of a sensor node of a wireless sensor network. More particularly, the present invention relates to an optimized number of active sensor nodes capable of guaranteeing coverage and connectivity of a wireless sensor network. The present invention relates to a method of probabilistically determining an operating state of a sensor node using the calculation.

Recently, due to the development of wireless communication and electronics technology, a network between low-cost, ultra-small sensors is possible. A network composed of these sensors is called a wireless sensor network.

Wireless sensor networks are used for ecological environment monitoring, intelligent environment monitoring, location awareness services, intelligent medical systems, and intelligent robotic systems, and are developing as a core technology of ubiquitous computing environment.

A wireless sensor network is a sensor node that senses, measures, and transmits physical data such as light, sound, temperature, and movement in the physical space, and a central primary node (sink node, sink) that receives and analyzes data transmitted from the sensor node. -node).

Sensor nodes typically include one or more sensors, actuators, microcontrollers, tens of kilobytes of EEPROM, several kilobytes of SRAM, hundreds of kilobytes of flash memory, analog-to-digital converters (ADCs), short-range wireless communication modules, and such. It is composed of a power source (energy source) for supplying power to the components.

In the wireless sensor network, sensor nodes are densely arranged in the sensor field for accurate information collection and reliability, and a plurality of sink nodes may be included according to a user's setting.

Due to the nature of the wireless sensor network, in most environments in which the wireless sensor network is applied, the sensor node has to operate for a long time and has a very limited resource because it is impossible to replace various components.

Among the limited resources, the decisive factor determining the survival time of the wireless sensor network is limited power. The survival time of the wireless sensor network is determined by how efficiently the limited power can be used.

The most energy-consuming component of the sensor is the RF (Radio Frequency) part, which is related to the wireless transmission and reception of data. The performance and survival time of the network varies depending on how effective the wireless communication networking technology is. .

Therefore, technologies that enable efficient power consumption while maintaining the coverage and connectorivity of the wireless sensor network have been studied, and as a result, to differentially control the operation state of the sensor according to a predetermined algorithm. Methods are suggested.

Conventional wireless sensor network coverage and connectorivity related technologies make up a tree of nodes that are activated by using the distance and angle with neighboring sensor nodes among the nodes placed in the sensor field. Techniques for excluding a node covered by neighboring sensor nodes, and techniques for placing a sensor node in a vulnerable area among sensor fields, have been proposed.

However, the related art has a problem in that it is difficult to simultaneously satisfy the coverage and the connectorivity of the wireless sensor network.

In addition, when determining the activity of the sensor according to the prior art, there was a problem that can not properly cope with changes in the surrounding environment.

In order to solve the problems of the prior art as described above, the present invention uses the activation probability calculated by the area information and the network information, and the coverage of the sensor field and the activated node by the minimum nodes activated. The purpose of the present invention is to provide a method for determining sensor node activation by a guaranteed probabilistic technique.

In order to achieve the above object, according to a preferred embodiment of the present invention, as a method for determining the sensor node activation of a wireless sensor network, (1) the state of the sensor node is set to Listen and neighboring sensors Obtaining information of a neighbor sensor node through wireless data communication with the node; (2) Calculate the minimum number of active nodes (N _CON ) that can guarantee coverage and connectivity of the entire network using the sensing radius (r) of the sensor node and the area (U) of the sensor field. Doing; 3, the group using the minimum number of active nodes (N _CON) for calculating the average of the neighboring sensors node (MN _CON) to ensure the coverage (coverage) and the connector Beattie (connectivity) of the network at an arbitrary sensor node step; (4) calculating an active probability (P _Active ) of a sensor node using the mean neighboring sensor node number (MN _CON ); And (5) determining whether a sensor node is activated using the active probability (P _Active ). A method of determining probability based sensor activation in a wireless sensor network is provided.

Definitions of terms used below are as follows.

U: sensing field, area of sensing field.

MN _COV : Average number of neighbor sensor nodes needed to ensure network coverage.

N _CON : Minimum total number of nodes to satisfy connectority.

MN _CON : Minimum number of neighbor sensor nodes needed to meet connector connectivity.

N: Total number of neighbor sensor nodes that can be checked by periodic HELLO messages from the sensor nodes.

P _Active : Active probability.

Round: When reporting of the sensing results of the active nodes ends with respect to the query message sent by the sink node.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the method for determining the probability-based sensor activation in the wireless sensor network.

1 is an exemplary configuration diagram of a wireless sensor network.

As shown in FIG. 1, the wireless sensor network includes a sink node 102 and a plurality of sensor nodes 120, 102, 104, 106, 108, 110, etc. installed in the sensing field (U = m * m) 100. Hereinafter referred to as a 'node'.

Hereinafter, the present invention will be described in detail with reference to any sensor node S 120.

Depending on the network design, the number of sink nodes and sensor nodes can be arbitrarily changed.

The sensor node 120 detects and measures various events generated within its sensing radius r, and transmits the information to the sink node 102, which transmits the information from the sensor node 120. It receives the information to perform various data processing.

The sensor node 120 transmits and receives data using short-range wireless data communication between the sensor nodes 104, 106, 108, and 110 or between the sensor node 120 and the sink node 100.

In the sensor network, coverage and connectivity are important issues. Coverage problems are areas that cannot be sensed by the active sensor nodes among randomly placed sensor nodes in the place where monitoring is needed. The problem of preventing the occurrence of a sensing hole is the problem of preventing the occurrence of a communication hole in which communication between the activated sensor nodes or between the sensor node and the sink node is impossible.

In the present invention, to ensure the coverage and connector connectivity of the sensor network, to satisfy the average number of neighbor sensor nodes (MN _COV ) and network connector connectivity (Connectivity) required to ensure network coverage (coverage) If you calculate the minimum number of neighboring sensor nodes (MN _CON ) needed to achieve this, and the difference between MN _CON and MN _COV is always greater than or equal to zero, you can activate only the nodes that guarantee network connectivity. It shows how to calculate the active probability (P _Active ) of the sensor node according to the MN _COV calculated using this, and proposes a method of controlling the active state of the sensor node according to the activity probability.

Will be described in detail calculated activity probability (P _Active) the process according to the present invention with reference to the accompanying drawings.

2A and 2B are exemplary diagrams illustrating a model for partition prediction.

2A and 2B, a process for _{obtaining an} average neighbor sensor node number MN _COV necessary to ensure network coverage will be described in detail.

2A is an exemplary diagram illustrating an area covered by a neighbor sensor node n1 140 when an arbitrary sensor node S 120 has one neighbor sensor node n1 104. May be calculated through Equation 1.

In Equation 1, r is the sensing radius of the sensor.

That is, when any sensor node S 120 has one neighbor sensor node n1 104, the area not covered by the neighbor sensor node n1 104 is on average in the sensor node area − It is about 41% of the area where sensor node S 120 senses.

2B is an example showing an area covered by a neighbor sensor node n1 104, n2 106 when any node S 120 has two neighbor sensor nodes n1 104, n2 106. As a diagram, an area not covered is calculated through the equation (2).

In Equation 2, k is the number of neighbor sensor nodes connected to sensor node S 120, and UCA (k) is a sensing radius of sensor node S 120 when k nodes are connected to sensor node S 120. It shows the area which is not covered.

Assuming that the sensor nodes are arranged in a uniform random manner, when there are two neighboring sensor nodes, 41% of the 41% sensor node area not covered by the neighboring sensor node n1 104 is not covered. Will remain.

The value of k when the result of Equation 2 is close to zero, that is, the number of neighboring sensor nodes needed to completely cover one sensor node area.

This result can be normalized through Equation 3.

In Equation 3, ε is defined as a number very close to zero, and the average neighboring sensor node number MN _COV necessary to ensure network coverage can be obtained from the sensing radius r of the sensor node.

3A, 3B, and 3C are exemplary views showing areas connected according to the number of connected nodes, and with reference to the accompanying drawings, the minimum number of neighboring sensor nodes required to satisfy connector connectivity according to the present invention ( It describes in detail how to calculate N _CON ).

The probability that any node n1 302 becomes a neighbor of sensor node S 300 is (πr ² / U), where the sum of the sensing areas by sensor node S 300 and any node n1 302 is obtained. Can be obtained as shown in Equation 4.

Here, U (100) is the area of the sensing field, it is assumed to be m * m.

SA (k) means the sum of the sensing areas when k nodes are connected to an arbitrary sensor node S 300.

That is, when two sensor nodes are connected, the sum of the sensing areas of the two sensor nodes is the difference between the sensing radius of the sensor node S 300 and the sensing area of the arbitrary node n1 302 and the sensor node S 300. It is the sum of the sets.

This value reflects the probability that an arbitrary node n1 302 becomes a neighbor of the sensor node S 300 in Equation 4.

When k nodes are connected to the sensor node S 300, the sum of the sensing areas by the k nodes is normalized as shown in Equation 5 below.

That is, even when any node n1 302, n2 304, n3 306, n4 308 is connected to the sensor node S 300 as shown in FIGS. 3B and 3C, the sum of the sensing areas is equal to. It may be calculated through Equation 5.

When the sensing area by the interconnected nodes becomes greater than or equal to the total sensing area, the value of k is the minimum number of nodes (N _CON ) to satisfy the connector connectivity of the network. You can get it.

Of course, if it is not an integer value, it should be rounded up to an integer value.

In addition, the average neighbor sensor node number MN _CON may be obtained by substituting Equation 6 with a minimum number N _CON of nodes for satisfying the connector connectivity calculated using Equation 5.

If the difference between the average number of neighbor sensor nodes (MN _CON ) needed to guarantee connector connectivity and the average number of neighboring sensor nodes (MN _COV ) required to ensure coverage is always greater than or equal to zero, If you activate only nodes that guarantee), coverage is automatically satisfied, which can be obtained as a function of the total network size and the node's sensing and communication radius.

Therefore, if the network design is designed to be greater than or equal to the average number of neighbor sensor nodes (MN _CON ) needed to ensure connector connectivity, the number of neighbor neighbor sensor nodes (MN _COV ) required to ensure coverage. Enabling only _CON ensures that both the connector connectivity and coverage of the network are guaranteed.

Of course, the design may also configure the network through the above-described process, or after the sensor node 120 of the network acquires the information of the neighbor sensor node and compares the MN _COV and the MN _CON , the MN _CON is large or Only in the same case may be configured to determine the activation of the sensor node through the activation determination method according to the present invention.

Using the total number of neighbor sensor nodes (N) identified by periodic HELLO messages at each node, and the average number of neighbor sensor nodes (MN _CON ) required to satisfy the connector connectivity, the active probability (P _Active ) is determined. Obtain

P _Active is defined as in Equation 7.

Equation (7) in determining the activation of the sensor node 120, when the number of neighboring sensor nodes (N) is less than the minimum value that can ensure the overall network coverage and connector connectivity (sensor node 120) ) Is unconditionally set to an activated state, and if the number of neighboring sensor nodes (N) is greater than the minimum value, it means that the probability is determined as belonging to a node group to be activated.

수학식으로 산출되는 활성확률(P_Active)에 의하여 센서 노드의 활성화를 결정하도록 구성되는 것이다.That is, the sensor node 120 compares the total number of neighbor sensor nodes (N) with the average number of neighbor sensor nodes (MN _CON ), so that the total number of neighbor sensor nodes (N) is smaller than the average number of neighbor sensor nodes (MN _CON ). In this case, the state of the sensor node is unconditionally activated, and when the total number of neighbor sensor nodes (N) is greater than or equal to the average number of neighbor sensor nodes (MN _CON ),

It is configured to determine the activation of the sensor node by the active probability (P _Active ) calculated by the equation.

Figure 4 is a round configuration diagram of a wireless sensor network, Figure 5 is a sensor node state transition diagram according to a preferred embodiment of the present invention.

Hereinafter, a state transition process of a sensor node according to the present invention will be described in detail with reference to the accompanying drawings.

The round refers to a time point at which the report on the sensing result of the activated sensor nodes ends with respect to the query message transmitted by the sink node 102.

The configuration of the round and the update interval of neighboring sensor node information of the sensor node 120 are defined as shown in FIG. 4.

The point at which the query is transmitted from the sink node 102 becomes the start point of each round, the sensor node 120 receives the query and performs the task, and transmits the result to the sink node 102 so as to transmit the result. ) Is the end of each round.

Sensor node 120 is configured to perform wireless communication to receive a query sent from sink node 102 during the time T _q of receiving each round of queries.

Several rounds are combined to form an update period Tu, which listens for the sensor node 120 to periodically acquire information about neighboring sensor nodes 104, 106, 108, 110, and so on. It is a reference to transition to the (Listen) state.

As shown in Fig. 5, each node is in one of three states (Listen, Sleep, and Active).

In the network initialization step, the sensor node 120 stays in a Listen state, and acquires neighbor sensor node information to calculate an activation probability P _Active .

Sensor node 120 is in active (Active) to the inactive state to the probability 1-P of the _Active by the calculated probability (Sleep) and the probability of P _Active transition to the next round.

In the sleep state, the sensor node 120 turns off the radio, transitions to the active state with a probability of P _{Active in} the next round, and stays in a sleep state with a probability of 1-P _Active .

The sensor node 120 in an active state refers to an activated node and refers to a node capable of participating in sensing and data routing.

In active (Active) state sensor node 120 is staying in the active (Active) state to the next round with a probability of P _Active, it will transition to the inactive (Sleep), the state to the next round with a probability of 1-P _Active.

On the other hand, if the sensor node 120 in the active state does not receive the query within the time T _q of receiving the query, the sensor node 120 immediately transitions to the sleep state.

This is because the sensor nodes are independently separated.

All nodes periodically transition to Listen state unconditionally in order to update the entire neighbor sensor node information, which may be preset or in a query message sent from the sink node 102. It may be included.

For example, if the update period T _u is set to 12 in the query message, all sensor nodes must transition to Listen after 12 rounds.

6 is a flowchart illustrating a sensor node activation determination process according to an embodiment of the present invention.

Hereinafter, a sensor node activation determination process according to a preferred embodiment of the present invention will be described in detail with reference to FIG. 6.

In the initialization phase of the wireless sensor network, each sensor node 120, 104, 106, 108, 110, etc., which will be described below based on any sensor node S 120, listens for the operation state of the node. Set the state (S600), and obtain information of the neighboring sensor node through the short-range wireless communication with the neighboring sensor nodes (S602).

The sensor node 120 transmits a 'Hello' message to each of the neighboring nodes 104, 106, 108, and 110 (in its own communication radius), and receives the number of neighboring sensor nodes that receive the response message. Define as N and save.

In this case, each sensor node 120 may be configured to obtain information of neighboring sensor nodes at a hop distance from itself, and may be configured to acquire only information of neighboring sensor nodes within a certain distance according to the setting. Can be.

The sensor node 120 uses the information of the wireless sensor network (the area of the sensing field, the sensing radius of the sensor node, the communication radius of the sensor node, etc.) and the average number of neighboring sensor nodes (MN _CON ) required to guarantee coverage. Calculate the minimum number of neighboring sensor nodes (N _CON ) required to satisfy the connector connectivity, and the average number of neighboring sensor nodes (MN _COV ) required to ensure the connectivity, and Using the neighbor sensor node information acquired in step S600, an active probability P _Active of a sensor node is calculated (S604).

The information of the wireless sensor network (area of the sensing field, the sensing radius of the sensor node, the communication radius of the sensor node, etc.) may use a preset value when designing the network, or data transmitted from the sink node 102. It may be configured to receive and use.

Average number of neighbor sensor nodes (M _CON ) required to ensure coverage, minimum number of neighbor sensor nodes (N _CON ) required to meet connector connectivity, average neighbors required to ensure connector connectivity Since the method of calculating the number of sensor nodes MN _COV and the active probability P _Active of the sensor nodes has been described above, a detailed description thereof will be omitted.

The sensor node 120 initializes the round count T _C to 0 to count the number of rounds in progress (S606).

Typically, the sensor node 120 has a change in its capacity due to various causes under a natural state other than an ideal state.

That is, a failure may occur and fall into an inoperable state, and since the failure may be restored and become operational again, in order to determine the active probability P _Active of the sensor node by reflecting the state of the sensor node 120. In the present invention, when a certain round passes, the operation state of the sensor node 120 is forcibly set to the Listen state and the sensor node 120 is controlled to obtain information of neighboring neighbor sensor nodes again.

The round count T _C is a constant variable for counting the number of rounds in progress, and is configured to increase by one for each round, and the sensor node 120 is preset with the round count Tc or The information of the neighbor sensor node is updated as compared with the update period Tu included in the query transmitted from the sink node 102.

The sensor node 120 calculates the total number N of neighboring sensor nodes neighboring the sensor node acquired in step S602 and the average number of neighbor sensor nodes MN _CON required to guarantee the connector connectivity calculated in step S604. In operation S608, when the total number N of sensor nodes adjacent to the sensor node is smaller than the number of MN _CONs , the operation state is set to active (S624).

If the total number N of sensor nodes adjacent to the sensor node 120 is smaller than the number of MN _CONs , all nodes in the vicinity including the sensor node 120 should be activated to ensure the connectivity of the network. In this case, the present invention is configured such that the operation state of the sensor node 120 is not determined probabilistically, but is set to an active state unconditionally, thereby ensuring the maximum performance of the network.

This process may be a separate step to compare the total number of neighboring sensor nodes (N) and the number of MN _CON , and to allow the operating state of the sensor node 120 to be controlled according to the result, the activation probability ( P _Active ) may be configured to perform at the step of determining whether to activate.

That is, since the activation probability P _Active is defined as MN _CON / N, when N is smaller than MN _CON , the activation probability P _Active may be configured to be set to an unconditional state because the activation probability P _Active becomes 1 or more.

When the sensor node 120 is set to the active state, the sensor node 120 receives a query transmitted from the sink node 102 to perform a task corresponding to the query and transmits the result to the sink node 102. .

At this time, the sensor node 120 increases the round count Tc by one at the end of each round (S626), and compares the update period Tu with the round count Tc to the update period (Tc). If smaller than Tu), the process returns to step S624, and if the round count Tc is equal to or larger than the update period Tu, the process returns to step S600.

The update period Tu is a number of rounds in which the sensor node 120 returns to step S600 to forcibly acquire the information of the neighbor sensor node. The update period Tu may be set in advance, and a query transmitted from the sink node 102. It may be configured to be included in.

The sensor node 120 compares in step S608 and, as a result, when the total number N of sensor nodes adjacent to the sensor node 120 is greater than or equal to the number of MN _COVs , the activity probability P calculated in step S604. _Active ) determines whether to activate the sensor node (S610).

Means for determining whether to activate the sensor node 120 by the active probability (P _Active ) may be a variety of, and in determining whether to activate the sensor node 120 using means obvious to those skilled in the art It is configured to reflect (P _Active ).

For example, a method of randomly generating a constant constant and comparing the value with a probability value, and setting it to an inactive state when it is large and setting it to an active state when it is small or the same according to the comparison result may be used. will be.

When the operation state is determined to be activated in operation S610, the sensor node 120 sets the operation state to an activation state, receives a query transmitted from the sink node 102, and performs a task corresponding to the query (S620).

However, when the sensor node 120 is set to an active state and performs wireless communication to receive a query transmitted from the sink node, but the query transmitted from the sink node 102 is not received within the query reception time Tq, The sensor node 120 automatically sets the operation state to an inactive state (S622).

The query reception time Tq is a time set to attempt wireless communication to receive a query in one round, and may be configured in advance or included in a query transmitted from the sink node 102.

Failure to receive a query during the query reception time (Tq) means that the sensor node 120 is isolated from the wireless network due to various obstacles (bad weather, inoperability of the sink node, etc.). ) State is meaningless even if it is activated, so it is forcibly set to the inactive state to prevent power consumption.

When the sensor node 120 is determined to be in an inactive state in operation S610, the sensor node 120 sets the operation state to an inactive state and waits for a predetermined round (ie, an update period Tu) in operation S620.

The sensor node 120 determines whether the sensor node 120 is activated according to an active probability (PActive) (activation state or inactivation state), and then increases the round count Tc by one (S616), and sets the updated update period (update). If the round count Tc is smaller than the update period Tu compared to the period period Tu, the process returns to step S610 and if the round count Tc is equal to or larger than the update period Tu, step S600. Return to (S618).

Through the above-described process, the sensor node 120 is able to probabilistically determine whether to activate the sensor according to the state of the surrounding environment.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

As described above, according to the probability-based sensor activation determination method in the wireless sensor network according to the present invention, it is possible to extend the life of the sensor network by determining whether to activate the sensor node according to the probability.

In addition, according to the present invention, there is an advantage that it is possible to efficiently use the resources of the limited sensor node while ensuring the coverage (coverage) and connectivity (connectivity) of the network.

In addition, according to the present invention, as the state of all sensor nodes is determined based on the activation probability adaptive to local information, the control of the flexible sensor nodes is possible, so that the performance of the sensor network can be guaranteed in various environments. have.

Claims (8)

A method for determining sensor node activation of a wireless sensor network, (1) setting the state of the sensor node to Listen and obtaining information of the neighboring sensor node through wireless data communication with the neighboring sensor node; (2) Calculate the minimum number of active nodes (N _CON ) that can guarantee coverage and connectivity of the entire network using the sensing radius (r) of the sensor node and the area (U) of the sensor field. Doing; (3) calculating an average number of neighboring sensor nodes (MN _CON ) that can guarantee coverage and connectivity of a network at any sensor node using the minimum number of active nodes (N _CON ). ; (4) calculating an active probability (P _Active ) of a sensor node using the mean neighboring sensor node number (MN _CON ); And (5) a method of determining a probability based sensor activation in a wireless sensor network, comprising determining whether a sensor node is activated using the active probability P _Active . According to claim 1, wherein step (2),

Probability-based sensor activation determination method in a wireless sensor network, characterized in that for calculating the minimum number of active nodes (N _CON ) using the equation. According to claim 1, wherein step (3),

Probability-based sensor activation determination method in a wireless sensor network, characterized in that to calculate the average number of neighboring sensor nodes (MN _CON ) using the equation. According to claim 1, wherein step (4),

Probability-based sensor activation determination method in a wireless sensor network, characterized in that to calculate the active probability (P _Active ) of the sensor node using the equation. 2. The method of claim 1, wherein the step (1) obtains information of one hop neighbor sensor node. The method of claim 1, After step (3), when the number of neighbor sensor nodes obtained in step (1) is compared with the number of neighboring sensor nodes (MN _CON ) calculated in step (3), the number of neighbor sensor nodes is large. Proceeding to step (4), if the number of neighboring sensor nodes is small, Probability-based sensor activation determination method in the wireless sensor network, characterized in that further comprising the step of setting the operating state of the sensor node to active. According to claim 1, wherein step (4), (A) determining whether the sensor node is activated according to a predetermined algorithm using the active probability (P _Active ); And (B) when the sensor node is set to an active state in the step (A), if the sensor node does not receive a query from the sink node within a predetermined query reception time (Tq), comprising setting the sensor node to an inactive state Probability-based Sensor Activation Determination Method in Wireless Sensor Networks. The method according to claim 6 or 7, Determining whether the preset number of rounds has been reached, repeating each step if the preset number of rounds has not been reached, and returning to step (1) if the preset number of rounds has been reached. Probability-based Sensor Activation Determination in Wireless Sensor Networks.

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