WO2014169640A1

WO2014169640A1 - Method, system, and sensor for adjusting detection frequency of sensor node

Info

Publication number: WO2014169640A1
Application number: PCT/CN2013/087331
Authority: WO
Inventors: 程伟; 徐勇; 李勇
Original assignee: 华为技术有限公司
Priority date: 2013-04-16
Filing date: 2013-11-18
Publication date: 2014-10-23
Also published as: CN104113896A

Abstract

Provided in embodiments of the present invention are a method, system, and sensor for adjusting a detection frequency of a sensor node. When a to-be-detected target is detected to have left a detection area of the sensor node, a prediction is made on whether or not the to-be-detected target will enter a detection area of the neighboring node, thus acquiring a prediction result. A frequency instruction message for instructing the neighboring node whether to employ a high detection frequency or a low detection frequency for detection is transmitted to the neighboring node on the basis of the prediction result. Correspondingly, when the frequency instruction message received by the sensor node is a first frequency instruction message that instructs the sensor node to employ the high detection frequency for detection, the high detection frequency is employed for detection of the to-be-detected target. When the frequency instruction message received is a second frequency instruction message that instructs the sensor node to employ the low detection frequency for detection, the low detection frequency is employed for detection of the to-be-detected target. This reduces the overall power consumption of a wireless sensor network. The present invention relates to the technical field of sensors.

Description

Method, system and sensor for detecting frequency of sensor node

The present invention relates to the field of sensor technologies, and in particular, to a method, system and sensor for detecting a frequency of a sensor node. Background technique

Wireless Sensor Networks (WSN) are network systems formed by a large number of sensor nodes deployed in the monitoring area and coordinated by radio communication.

Each sensor node has a probe radius and a communication radius. The detection radius indicates that the sensor node can detect the detection area of the target. It is generally considered that the detection area of the sensor node is a circular area with a radius R1 centered on the sensor node. When the sensor node detects the target for the first time, the target is considered to be located. The detection radius is the boundary line of the circular area of R1, and the position point on the boundary line where the target is located at this time is the entry point of the target entering the detection area of the sensor node; similarly, when the sensor node loses the target for the first time, The target can be considered to be on the boundary line of the circular area with the detection radius R1, and the position point on the boundary line where the target is located at this time is the departure point of the target leaving the detection area of the sensor node. In order to detect the target more accurately, the sensor nodes in the wireless sensor network are usually able to cover the monitoring area redundantly, that is to say there are overlapping detection areas i or between the sensor nodes.

The communication radius indicates the maximum distance that the sensor node can communicate with the neighbor node of the sensor node. It is generally considered that the communication area of the sensor node is a circular area with a communication radius of R2 centered on the sensor node, that is, with the sensor. A sensor node whose distance between nodes is not greater than R2 can be used as a neighbor node of the sensor node. The detection radius R1 of the sensor node can be greater than, less than or equal to its communication radius R2.

An important application of sensor networks is to locate targets entering the wireless sensor network. And tracking. Sensor nodes in sensor networks typically work as follows:

Initializing a sensor node in the sensor network, setting a detection frequency of the sensor node, and recording, for each sensor node, status information of each neighbor node corresponding to a target to be tested;

The neighbor node status information includes a location relationship between the neighbor node of the sensor node and the object to be tested, that is, the object to be tested is located in the detection area of the neighbor node, or the target to be tested is not located in the detection area of the neighbor node. During initialization, the position relationship between each neighbor node and the above-mentioned object to be tested is initialized to be that the target to be tested is not located in the detection area of the neighbor node.

The sensor node updates the state information of the neighbor node stored by itself by receiving a location indication message sent by each neighbor node that characterizes the location relationship between the target to be tested and each neighbor node. For example, when the target to be tested enters the neighboring node detection area of the sensor node, the neighboring node sends a location indication message that the target to be tested is located in its own detection area to its neighbor node (including the sensor node), and correspondingly, When the target to be tested leaves the detection area of the neighbor node of the sensor node, the neighbor node sends a location indication message that the target to be tested is not in its own detection area to its neighbor node (including the sensor node).

When detecting that the target to be tested enters the detection area of the sensor node, the determined entry target enters the detection point of the detection area of the sensor node and sends the location to the designated device (usually a base station), and the designated device according to the received sensor node The location of the transmitted entry point, and the received entry points of the other target nodes when the target to be tested enters the detection area of the other neighbor nodes, calculates the motion track of the target to be measured, and implements tracking of the target to be measured.

However, in the prior art, when the sensor nodes in the wireless sensor network are initialized, each sensor node maintains a fixed detection frequency to detect the target, that is, the detection frequency of the sensor node cannot be dynamically adjusted. For example, in the case where no target enters the wireless sensor network, or the target is only active in a part of the detection area covered by the wireless sensor network, all sensor nodes in the wireless sensor network use a fixed detection frequency to detect the target. This makes the wireless sensor network consume more power. Summary of the invention

The embodiment of the invention provides a method, a system and a sensor for adjusting a detection frequency of a sensor node, which are used to solve the problem that the detection frequency of all sensor nodes in the wireless sensor network is fixed in the prior art, so that the wireless sensor network consumes a large amount of power. The problem.

In a first aspect, a method for adjusting a detection frequency of a sensor node is provided, including:

Determining the motion of the target to be tested according to the entry point position and the exit point position in the detection area of the sensor node in the current detection period when detecting the detection target leaving the detection area of the sensor node Directional motion vector;

Determining, according to a location of the sensor node, a location of a neighbor node of the sensor node, and a positional relationship between the motion vectors, whether the target to be tested is to enter a detection area of the neighbor node to obtain a prediction result;

And transmitting, according to the prediction result, a frequency indication message to the neighboring node, where the frequency indication message indicates that the neighboring node performs detection by using a high detection frequency or a low detection frequency.

With reference to the first aspect, in a first possible implementation, before detecting a motion vector of a motion direction of the target to be tested, when detecting that the target to be tested enters a detection area of the sensor node, the sensor The node sends a first frequency indication message indicating that the neighboring node uses the high-detection frequency to detect the neighboring node, and sends a frequency indication message to the neighboring node according to the prediction result, specifically: when predicting If the result is no, a second frequency indication message indicating that the neighboring node uses the low detection frequency for detecting is sent to the neighboring node.

With reference to the first aspect, in a second possible implementation manner, the sending, by the neighboring node, the frequency indication message according to the prediction result, specifically: when the prediction result is yes, sending the neighboring node to the neighboring node And detecting, by the node, a first frequency indication message that is detected by using a high detection frequency; and when the prediction result is no, sending, to the neighboring node, a second frequency indication message indicating that the neighboring node detects by using a low detection frequency.

With reference to the first aspect, in a third possible implementation manner, according to a location of the sensor node, a location of the neighbor node of the sensor node, and a positional relationship between the motion vectors, Predicting whether the target to be tested is to enter the detection area of the neighbor node to obtain a prediction result, specifically, comprising: acquiring a preset direction vector of a location of the sensor node that points to a location of the neighbor node; determining the direction vector and An angle between the motion vectors; when the angle between the direction vector and the motion vector is greater than a preset angle threshold, predicting that the target to be tested is not about to enter the detection area of the neighbor node; When the angle between the direction vector and the motion vector is not greater than a preset angle threshold, the target to be tested is predicted to enter the detection area of the neighbor node.

With reference to the first aspect, or in combination with the first possible implementation of the first aspect, in a fourth possible implementation, the location of the sensor node, the location of the neighbor node of the sensor node And determining a positional relationship between the motion vectors, and predicting whether the target to be tested is to enter the detection area of the neighboring node to obtain a prediction result, specifically: acquiring a preset location of the sensor node to point to the neighbor node a direction vector of the position; determining an angle between the direction vector and the motion vector; predicting the target to be tested when an angle between the direction vector and the motion vector is greater than a preset angle threshold a detection area that is not to enter the neighboring node; when an angle between the direction vector and the motion vector is not greater than a preset angle threshold, when determining a detection area that leaves the sensor node from the object to be tested When the target to be tested does not enter the detection area of the sensor node, the prediction is within the preset duration Said object to be measured not to enter the detection area neighbor node.

With reference to the fourth possible implementation of the first aspect, in a fifth possible implementation, the preset duration is determined by: according to the target to be tested, currently in the detection area of the sensor node Determining a moving distance of the object to be tested in a detecting area of the sensor node according to the entry point position and the leaving point position; and entering an accessing time of the detecting area of the sensor node according to the object to be tested Determining a movement time of the object to be tested from the detection area of the sensor node, and determining a movement time of the object to be tested in the detection area of the sensor node; according to the movement distance and the movement time Determining a speed of movement of the object to be tested in a detection area of the sensor node; determining that the preset duration is a ratio of a product of a preset coefficient to a radius of a detection area of the sensor node to the motion speed. With reference to the first aspect, in a sixth possible implementation, determining, by using the following manner, the leaving point position of the detecting target in the detecting area of the sensor node: when detecting that the target to be tested leaves the a detection area of the sensor node is respectively obtained, and a boundary between the sensor node and each neighbor node is obtained, where an intersection boundary between the sensor node and the neighbor node is a detection area of the sensor node and a boundary of the detection area of the sensor node in a boundary of the overlap area of the detection area of the neighbor node; determining, from the neighbor nodes, each first neighbor node in the detection area of the target to be detected, and determining a first overlapping boundary of each intersection boundary between the sensor node and each of the first neighboring nodes; determining, from each of the neighboring nodes, each second neighboring node that the object to be tested is not located in the detecting area And respectively determining an intersection boundary between the sensor node and each of the second neighbor nodes and the first overlapping boundary a second overlapping boundary; determining a position of the leaving point of the detecting area of the target node passing through the sensor node, and a boundary range on a boundary of the detecting area of the sensor node, except for the first overlapping boundary a boundary outside the second overlapping boundary; determining, according to the boundary range on a boundary of the detecting area of the sensor node, a position of the leaving point of the detecting area of the sensor node.

With reference to the first aspect, or in combination with the above various possible implementation manners of the first aspect, in the seventh possible implementation, the entry point of the detection area of the sensor node is currently according to the object to be tested. Position and the leaving point position, determining a moving distance of the object to be tested in a detecting area of the sensor node; entering an access time of the detecting area of the sensor node according to the object to be tested, and Determining, by the target, the departure time of the detection area of the sensor node, determining the motion time of the object to be tested in the detection area of the sensor node; determining the to-be-waited according to the motion distance and the motion time Measuring the speed of movement of the target within the detection area of the sensor node.

In a second aspect, a method for adjusting a detection frequency of a sensor node is provided, including:

The sensor node receives a frequency indication message sent by the neighbor node of the sensor node, where the frequency indication message is based on the location of the sensor node, the location of the neighbor node of the sensor node, and the motion vector of the target to be tested. Positional relationship determination; When the received frequency indication message is a first frequency indication message indicating that the sensor node uses a high detection frequency for detecting, the target to be tested is detected by using the high detection frequency;

When the received frequency indication message is a second frequency indication message indicating that the sensor node detects by using a low detection frequency, the target to be tested is detected by using the low detection frequency.

With reference to the second aspect, in a first possible implementation manner, the first frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested is to be Entering a detection area of the sensor node, and transmitting a frequency indication message to the sensor node; detecting the detection target to enter the detection area of the sensor node, and detecting the target to be tested by using the high detection frequency.

With reference to the second aspect, in a second possible implementation manner, the first frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested is to be a frequency indication message sent to the sensor node in the detection area of the sensor node; the second frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighbor node, and predicts A frequency indication message sent to the sensor node that the target to be tested will not enter the detection area of the sensor node.

With reference to the second aspect, in a third possible implementation manner, the first frequency indication message is that the neighboring node detects that the target to be tested enters the detection area of the neighboring node, and sends a frequency indication to the sensor node. The second frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node. a frequency indication message sent to the sensor node, or a frequency indication message sent by the neighboring node to the sensor node after a predetermined period of time has elapsed since the time when the target to be tested leaves the detection area of the sensor node And receiving, by the neighboring node, a location indication message that is not located in a detection area of the neighboring node that is sent when the to-be-detected target leaves the detection area of the neighboring node; Frequency indication message When the second frequency indication message that is detected by the sensor node is detected by using the low detection frequency, the target to be tested is detected by using the low detection frequency, specifically: when the received frequency indication message is indicating When the sensor node uses the second frequency indication message for detecting the low detection frequency, and the time between the time when the location indication message is received and the time when the second frequency indication message is received is less than the duration threshold, and the received Between the moment when the location indication message is received and the time when the second frequency indication message is received, the first frequency indication message sent by the other neighboring node is not received, and the target to be tested is detected by using the low detection frequency.

In a third aspect, a sensor is provided, including:

a determining module, configured to: when detecting a detection area where the target to be tested leaves the sensor node, determining, according to the entry point position and the exit point position in the detection area of the sensor node in the current detection period of the object to be tested a motion vector of a moving direction of the target to be tested;

a prediction module, configured to predict, according to a location of the sensor node, a location of a neighbor node of the sensor node, and a positional relationship between motion vectors determined by the determining module, whether the target to be tested is about to enter the neighbor The detection area of the node obtains the prediction result;

And a sending module, configured to send, according to the prediction result predicted by the prediction module, a frequency indication message to the neighboring node, where the frequency indication message indicates that the neighboring node performs detection by using a high detection frequency or a low detection frequency.

With reference to the third aspect, in a first possible implementation, the sending module is further configured to: when detecting that the object to be tested enters a detection area of the sensor node, the sensor node is to the neighbor node of the sensor node Transmitting, by the sending module, a first frequency indication message that is used by the neighboring node to detect the high-detection frequency, where the sending module is configured to: when the prediction result predicted by the prediction module is negative, send the indication to the neighboring node The second frequency indication message that the neighbor node uses the low detection frequency for detection.

With reference to the third aspect, in a second possible implementation, the sending module is specifically configured to: when the prediction result predicted by the prediction module is yes, send, to the neighboring node, the neighboring node to use a high detection frequency. The first frequency indication message of the probe; when the prediction result predicted by the prediction module is No, sending, to the neighboring node, a second frequency indication message indicating that the neighboring node detects by using a low detection frequency.

With reference to the third aspect, in a third possible implementation, the prediction module is specifically configured to acquire a direction vector of a position of the preset sensor node that is located at a position of the neighbor node, and determine the direction vector and the location Determining an angle between the motion vectors determined by the module; when the angle between the direction vector and the motion vector determined by the determining module is greater than a preset angle threshold, predicting that the target to be tested is not a detection area to be entered into the neighboring node; when the angle between the direction vector and the motion vector determined by the determining module is not greater than a preset angle threshold, predicting that the target to be tested is about to enter the neighbor The detection area of the node.

With reference to the third aspect, or in combination with the first possible implementation manner of the third aspect, in a fourth possible implementation, the prediction module is specifically configured to obtain a preset location of the sensor node, a direction vector of a position of the node; determining an angle between the direction vector and the motion vector determined by the determining module; an angle between the direction vector and the motion vector determined by the determining module When the threshold is greater than the preset angle, the predicted target is not to enter the detection area of the neighbor node; and the angle between the direction vector and the motion vector determined by the determining module is not greater than a preset angle At the threshold, when it is determined that the target to be tested has entered the detection area of the sensor node within a preset time period from the time when the target to be tested leaves the detection area of the sensor node, the prediction is to be tested. The target is not about to enter the detection area of the neighbor node.

With reference to the fourth possible implementation of the third aspect, in a fifth possible implementation, the prediction module is specifically configured to determine the preset duration according to the following manner: according to the target to be tested Determining a moving distance of the object to be tested in a detecting area of the sensor node according to the entry point position and the leaving point position of the detecting area of the sensor node; entering the sensor according to the object to be tested The time of entry of the detection area of the node, and the departure time of the detection area of the object to be tested from the sensor node, determining the movement time of the object to be tested in the detection area of the sensor node; The motion distance and the motion time determine a motion speed of the object to be tested in a detection area of the sensor node; determining the preset duration as a preset coefficient and the The ratio of the product of the radius of the detection zone of the sensor node to the velocity of the motion.

With reference to the third aspect, in a sixth possible implementation, the determining module is specifically configured to: determine, by using the following manner, the leaving point position of the detecting target in the detecting area of the sensor node: when detecting The detection target leaves the detection area of the sensor node, and obtains an intersection boundary between the preset sensor node and each neighbor node thereof, where the intersection boundary between the sensor node and the neighbor node is Defining a boundary of the detection area of the sensor node in a boundary between a detection area of the sensor node and an area of the detection area of the neighbor node; and determining, from each of the neighbor nodes, the object to be tested located in the detection area a first neighboring node, and determining a first overlapping boundary of each intersecting boundary between the sensor node and each of the first neighboring nodes; determining, from the neighboring nodes, that the target to be tested is not located in the detecting area thereof Each second neighbor node, and respectively determining a phase between the sensor node and each of the second neighbor nodes a second overlapping boundary of the boundary with the first overlapping boundary; determining a position of the leaving point of the detecting area of the target node passing through the sensor node, a boundary range on a boundary of the detecting area of the sensor node, a boundary other than each of the second overlapping boundaries of the first overlapping boundary; determining, according to the boundary range on a boundary of the detecting area of the sensor node, the target to be tested is currently in the sensor The point of departure of the detection area of the node.

With reference to the third aspect, or in combination with the foregoing various possible implementation manners of the third aspect, in a seventh possible implementation, the prediction module is specifically configured to be at the sensor node according to the target to be tested. Determining a moving distance of the object to be tested in a detecting area of the sensor node according to the entry point position and the leaving point position of the detecting area; and entering the detecting area of the sensor node according to the object to be tested The entry time, and the departure time of the detection target from the detection area of the sensor node, determining the movement time of the object to be tested in the detection area of the sensor node; The motion time determines a speed of movement of the object to be tested within a detection area of the sensor node.

In a fourth aspect, a sensor is provided, including:

a receiving module, configured to receive, by the sensor node, a frequency index sent by a neighbor node of the sensor node a message indicating that the frequency indication message is determined according to a location relationship between the location of the sensor node, a location of a neighbor node of the sensor node, and a motion vector of the target to be tested;

a frequency adjustment module, configured to: when the frequency indication message received by the receiving module is a first frequency indication message indicating that the sensor node uses a high detection frequency for detecting, using the high detection frequency to the to-be-tested The target is detected; when the frequency indication message received by the receiving module is a second frequency indication message indicating that the sensor node uses a low detection frequency for detecting, the low detection frequency is used to perform the target to be tested. probe.

With reference to the fourth aspect, in a first possible implementation manner, the first frequency indication message that is received by the receiving module is that the neighboring node detects that a target to be tested leaves a detection area of the neighboring node, and predicts a frequency indication message sent to the sensor node to be detected in the detection area of the sensor node; the frequency adjustment module is further configured to detect the detection target entering the detection area of the sensor node The detection is performed using the high detection frequency.

With reference to the fourth aspect, in a second possible implementation manner, the first frequency indication message that is received by the receiving module is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts a frequency indication message sent to the sensor node to be sent to the detection node of the sensor node, and the second frequency indication message received by the receiving module is detected by the neighbor node The target to be tested leaves the detection area of the neighbor node, and predicts that the target to be tested does not enter the detection area of the sensor node, and the frequency indication message is sent to the sensor node.

With reference to the fourth aspect, in a third possible implementation manner, the first frequency indication message that is received by the receiving module is that the neighboring node detects that the target to be tested enters the detection area of the neighboring node, a frequency indication message sent by the sensor node; the second frequency indication message received by the receiving module is that the neighboring node detects that the object to be tested leaves the detection area of the neighboring node, and predicts the waiting The measurement target does not enter the detection area of the sensor node, the frequency indication message sent to the sensor node, or the neighboring node passes the time when the target to be tested leaves the detection area of the sensor node. After the duration, the sensor node is The frequency indication message is sent; the receiving module is further configured to: when the neighboring node detects that the object to be tested leaves the detection area of the neighboring node, the target to be tested is not located in the neighboring node a location indication message in the area; the frequency adjustment module is configured to: when the frequency indication message received by the receiving module is a second frequency indication message indicating that the sensor node uses a low detection frequency for detecting, and a duration between a time when the receiving module receives the location indication message and a time when the second frequency indication message is received is less than a duration threshold, and a time when the location indication message is received and the second is received Between the moments of the frequency indication message, the first frequency indication message sent by the other neighboring node is not received, and the target to be tested is detected by using the low detection frequency.

A fifth aspect provides a detection frequency adjustment system for a sensor node, including: a first sensor node, which is a second sensor node of a neighbor node of the first sensor node, where:

The first sensor node is configured to: when detecting that the target to be tested leaves the detection area of the first sensor node, according to the entry point of the object to be tested in the detection area of the first sensor node in the current detection period Position and leaving point position, determining a motion vector of a moving direction of the object to be tested; predicting according to a position of the first sensor node, a position of the second sensor node, and a positional relationship between the motion vectors Whether the target to be tested is to enter the detection area of the second sensor node to obtain a prediction result; according to the prediction result, sending a frequency indication message to the second sensor node, the frequency indication message indicating the second sensor The node uses a high detection frequency or a low detection frequency for detection;

The second sensor node is configured to receive a frequency indication message sent by the first sensor node, where the received frequency indication message is a first frequency indication message that is used by the second sensor node to detect by using a high detection frequency. And detecting, by the high detection frequency, the target to be tested; when the received frequency indication message is a second frequency indication message indicating that the second sensor node uses a low detection frequency for detecting, The low detection frequency is used to detect the target to be tested.

Advantageous effects of embodiments of the present invention include: A method, system and sensor for detecting a detection frequency of a sensor node according to an embodiment of the present invention, when detecting a detection target leaving a detection area of a sensor node, according to the object to be tested, the detection area of the sensor node in the current detection period Determining the motion vector of the moving direction of the object to be tested, and determining the position according to the position of the sensor node, the position of the neighbor node of the sensor node, and the positional relationship between the motion vectors Whether the target to be tested is about to enter the detection area of the neighboring node to obtain a prediction result; according to the prediction result, a frequency indication message is sent to the neighboring node, and the frequency indication message indicates that the neighboring node detects by using a high detection frequency or a low detection frequency. Correspondingly, the sensor node can receive the frequency indication message sent by the neighboring node; when the received frequency indication message is the first frequency indication message indicating that the sensor node uses the high detection frequency for detecting, the target is to be measured with a high detection frequency. Performing detection; when the received frequency indication message is a second frequency indication message indicating that the sensor node uses a low detection frequency for detection, the target to be measured is detected by using a low detection frequency. The sensor node determines a neighboring node to be detected by using a high detection frequency or a low detection frequency according to the motion trend of the target to be measured in the detection area, and sends a corresponding frequency indication message to the neighbor node, and the neighbor node receives the corresponding frequency indication message. The frequency indication message is detected by using a high detection frequency or a low detection frequency according to its own situation. Compared with the prior art, all sensor nodes in the wireless sensor network reduce the overall power consumption of the wireless sensor network in any case by using a fixed detection frequency to detect the target to be measured. DRAWINGS

FIG. 1 is a flowchart of a method for adjusting a detection frequency of a sensor node according to an embodiment of the present disclosure;

2 is a second flowchart of a method for adjusting a detection frequency of a sensor node according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for adjusting a detection frequency of a sensor node as a transmission frequency indication message side according to Embodiment 1 of the present invention; Schematic diagram of one of the positional relationships of points;

FIG. 5 is a flowchart of a method for adjusting a detection frequency of a sensor node as a receiving frequency indication message side according to Embodiment 2 of the present invention;

FIG. 6 is a second flowchart of a method for adjusting a detection frequency of a sensor node as a transmission frequency indication message according to Embodiment 3 of the present invention; FIG.

8 is a second flowchart of a method for adjusting a detection frequency of a sensor node as a receiving frequency indication message according to Embodiment 4 of the present invention;

FIG. 9 is a structural diagram of a detection frequency adjustment apparatus for a sensor node according to an embodiment of the present invention;

FIG. 10 is a second structural diagram of a detection frequency adjustment device for a sensor node according to an embodiment of the present invention. detailed description

The specific method for adjusting the detection frequency of the sensor node, the system and the sensor are described below with reference to the accompanying drawings.

The method for adjusting the detection frequency of the sensor node provided by the embodiment of the present invention is applied to each sensor node in the sensor network as one side of the transmission frequency indication message. As shown in FIG. 1, the method includes the following steps:

5101. When detecting that the target to be tested leaves the detection area of the sensor node, determining the moving direction of the target to be tested according to the position of the entry point and the position of the exit point in the detection area of the sensor node in the current detection period. Sport vector.

5102. predicting, according to the location of the sensor node, the location of the neighbor node of the sensor node, and the positional relationship between the motion vectors, whether the target to be tested is to enter the foregoing The detection area of the neighbor node obtains the prediction result.

S103. Send a frequency indication message to the neighboring node according to the foregoing prediction result, where the frequency indication message indicates that the neighboring node performs detection by using a high detection frequency or a low detection frequency.

Further, the detection frequency adjustment method of the above sensor node is applicable to each neighbor node of the sensor node.

Further, before the step S101, the method may further include the following steps: when detecting that the object to be tested enters the detection area of the sensor node, the sensor node sends an indication to the neighbor node that the neighbor node uses the high detection frequency to detect The first frequency indication message. Correspondingly, in the foregoing step S103, if the prediction result is no, the second frequency indication message indicating that the neighboring node uses the low detection frequency for detecting is sent to the neighboring node. That is to say, the sensor node detects that the target to be tested enters its own detection area, and sends a first frequency indication message indicating that the neighboring node uses the high detection frequency for detecting, and detects the detection target leaving the detection area of the target. If it is predicted that the target to be tested is not about to enter the neighbor node, the neighboring node may send a second frequency indication message indicating that the neighboring node uses the low detection frequency for detecting, if it is predicted that the target to be tested is about to enter the neighbor. The node may not send a second frequency indication message indicating that the neighbor node uses the low detection frequency for detecting, and may not send a first frequency indication to the neighbor node indicating that the neighbor node uses the high detection frequency for detection. The message, because when the target to be tested enters the detection area of the sensor node, the sensor node has sent a first frequency indication message to the neighbor node indicating that the neighbor node uses the high detection frequency for detection.

Further, in the above step S103, when the sensor node detects that the target to be tested leaves its own detection area, predicts whether the target to be tested is about to enter the detection area of the neighbor node of the sensor node, and if the prediction result is yes, to the neighbor The node sends a first frequency indication message indicating that the neighboring node uses the high detection frequency for detecting. When the prediction result is no, the second frequency indication message indicating that the neighboring node uses the low detection frequency for detecting is sent to the neighboring node. That is to say, when the sensor node detects that the target to be tested leaves its own detection area, according to the motion trend of the target to be measured, it is predicted that the above detection will be performed with a high detection frequency or a low detection frequency will be used for detection, and The neighbor node sends a corresponding frequency indication message.

Corresponding to the method shown in FIG. 1 , the embodiment of the present invention further provides a method for adjusting a detection frequency of a sensor node, which is applied to each sensor node in the sensor network as a side of receiving a frequency indication message, as shown in FIG. 2 . The indication includes the following steps:

5201. The sensor node receives a frequency indication message sent by a neighbor node of the sensor node, where the frequency indication message is based on a location of the sensor node, a location of a neighbor node of the sensor node, and a location between motion vectors of the target to be tested. Relationship is determined.

5202. When the received frequency indication message is a first frequency indication message indicating that the sensor node uses a high detection frequency for detecting, the target to be tested is detected by using the high detection frequency.

S203. When the received frequency indication message is a second frequency indication message indicating that the sensor node uses a low detection frequency for detecting, the target to be tested is detected by using the low detection frequency.

Further, in the foregoing step S202, the first frequency indication message may be that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested is about to enter the detection area of the sensor node, and the sensor is a frequency indication message sent by the node; when the first frequency indication message received by the sensor node is used, detecting the target to be tested by using the high detection frequency; and the sensor node may also detect that the target to be tested enters the sensor node The detection area is detected by the above-mentioned high detection frequency. Correspondingly, in the foregoing step S203, the second frequency indication message may be that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node. , a frequency indication message sent to the above sensor node. When the frequency indication message received by the sensor node is the second frequency indication message indicating that the sensor node detects the low detection frequency, the target to be tested is detected by using the low detection frequency.

Further, in the foregoing step S202, the first frequency indication message may be that the neighboring node detects that the target to be tested enters the detection area of the neighbor node, and sends the frequency index to the sensor node. Correspondingly, in the foregoing step S203, the second frequency indication message may be that the neighboring node detects that the target to be tested is away from the detection area of the neighbor node, and predicts that the target to be tested does not enter the sensor node. a detection area, a frequency indication message sent to the sensor node, or a frequency indication message sent by the neighboring node to the sensor node after a predetermined period of time has elapsed since the time when the target to be tested leaves the detection area of the sensor node . In this case, when the frequency indication message received by the sensor node is the second frequency indication message, and receiving the location indication message that the target to be tested is not located in the detection area of the neighbor node, The duration between the times when the second frequency indication message is sent is less than the duration threshold, and between the time when the location indication message is received and the time when the second frequency indication message is received, the first one sent by the other neighbor node is not received. The frequency indication message is used to detect the target to be tested by using the low detection frequency.

Said.

Embodiment 1:

FIG. 3 is a flowchart of a method for adjusting a detection frequency of a sensor node as a transmission frequency indication message side according to Embodiment 1, and the specific steps are as follows:

S301. The sensor node detects that the target to be tested enters a detection area of the sensor node.

5302. The sensor node sends a first frequency indication message to the neighbor node indicating that the neighbor node uses the high detection frequency for detecting.

Further, in this step, when the sensor node detects that the target to be tested enters the detection area of the sensor node, it sends a first frequency indication message to its neighbor node, indicating that the neighbor node uses the high detection frequency for detection. That is, when detecting that the target to be tested enters the detection area of the sensor node and sends the first indication message, the neighbor node of the sensor node may be prepared for detection in advance, because the target to be tested may leave the detection area of the detection node at any time. The detection zone i or the neighbor node of the sensor node.

S303. The sensor detects that the target to be tested leaves the detection area of the sensor node. 5304. Determine, according to the entry point position and the exit point position of the detection area of the sensor node, the motion vector of the motion direction of the object to be tested.

Further, the motion vector of the motion direction of the target to be tested in this step may be that the entry point of the detection target that the target to be tested enters into the sensor node belongs to the detection area of the target node that is leaving the sensor node. The motion vector that leaves the point position. The motion vector characterizes the motion trend of the target to be tested.

5305. According to the location of the sensor node, the location of the neighbor node of the sensor node, and the positional relationship between the motion vectors, predict whether the target to be tested is about to enter the detection region of the neighbor node.

Further, this step can be implemented by the following steps:

Step 1: Obtain a preset direction vector of the location of the sensor node pointing to the location of the neighbor node;

Further, the position vector of the location of the sensor node in step 1 is directed to the direction vector of the location of the neighbor node, and may be pre-determined and stored when the sensor node is initialized, thereby avoiding transmission when determining the direction vector in the process of detecting the target to be tested. The amount of data is large, which consumes wireless sensor network resources.

Step 2, determining an angle between the direction vector and the motion vector;

Step 3: When the angle between the direction vector and the motion vector is greater than a preset angle threshold, predict that the target to be tested is not to enter the detection area of the neighbor node;

Step 4: When the angle between the direction vector and the motion vector is not greater than the preset angle threshold, when determining the preset duration from the time when the target to be tested leaves the detection area of the sensor node, The target to be tested does not enter the detection area of the sensor node, and it is predicted that the target to be tested is not to enter the detection area of the neighbor node.

The following is an example. Figure 4 is a schematic diagram showing one of the relationship between the motion trajectory of the target to be measured and the sensor node and its neighbor nodes, as shown in Figure 4:

N _x (at the center of the circle at the top), N _y (at the center of the circle at the far right), and N _z (at the center of the circle at the bottom) are three sensor nodes, and the detection area of ^ is Take O _x as medium The circular detection area with the radius R of the heart, the detection area of Ny is a circular detection area with the radius of R centered on Oy, and the detection area is a circular detection area with a radius of R centered on 0 ₂ . And the detection areas of the sensor nodes N _x , Ny , and are overlapped with each other, and the three are neighbor nodes. Suppose object to be measured has to move past the sensor tracks TrackA node N _x, N _y, and N _z is the detection region, the sensor node TrackA Ν _{_χ,} Ν γ, and N _Z intersection point detection area are A, B, C , D, E, F.

The target to be tested leaves the detection area of the sensor node N _z with the track of the track A, the point C is the entry point of the detection area of the target to enter the sensor node, and the point F is the departure point of the detection area of the target to leave the sensor node N _z . Determining that the motion vector of the target to be tested in the detection area of the sensor node N _z is CF, and because the direction vector of the sensor node to the sensor node N _x is O _z O _x , the direction vector of the sensor node N to the sensor node N _y is between O _z O _y, when the target to be detected away from the point F through the detection area of the sensor node N _z, N _z sensor nodes themselves are pointing direction determining sensor node N _x O _z O _x vector of the object to be measured motion vector CF The first angle between the first angle and the direction vector O _z O _y of the sensor node Ny and the motion vector CF of the target to be tested, if the first angle is greater than the preset angle threshold, the determined to be measured the target is not to enter the detection area of the sensor node N _x; Similarly, if the angle is greater than a second predetermined angle threshold value, it is determined not to be a target to be measured into the sensor detection area node N _y If the first angle is no greater than a predetermined angle threshold value, the departure time is determined when the detection area of the sensor node N _z from the target to be detected since, after the preset time length of the target to be detected does not enter the sensor node N _z The detection area predicts that the target to be tested is not about to enter the detection area of N _x ; similarly, if the second angle is not greater than the preset angle threshold, when it is determined that the detection target is away from the detection area of the sensor node N _z Within the preset duration, the target to be tested does not enter the detection area of the sensor node N _z , and predicts that the target to be tested is not going to enter the detection area of N _y .

Preferably, the preset angle threshold may be 90 degrees, or slightly less than 90 degrees, or slightly larger than 90 degrees.

Further, the following steps are used to determine the preset duration:

Step 1, determining, according to the position of the entry point of the detection target of the sensor node and the position of the exit point, the operation of the object to be tested in the detection area of the sensor node Moving distance

Step 2: determining, according to the entry time of the detection target entering the detection area of the sensor node, and the departure time of the detection area of the target to be tested from the sensor node, determining the detection of the target to be detected at the sensor node Movement time in the area;

Step 3: determining, according to the moving distance and the moving time, a moving speed of the target to be tested in a detection area of the sensor node;

Step 4: Determine the preset duration is a ratio of a product of the preset coefficient to the radius of the detection area of the sensor node to the motion speed.

Preferably, the preset coefficient may be 3, 4, 5, etc., and the product of the preset coefficient and the radius of the detection area of the sensor node represents the estimated distance, and it may be considered that if the target to be measured moves the estimated distance has not returned to the sensor node detection For the area, it can be considered that the target to be tested does not return to the motion trend of the detection area of the sensor node.

Further, in the step of determining the preset duration, the motion speed of the object to be tested in the detection area of the sensor node is determined. In the prior art, the sensor node determines the moving speed of the target to be tested in the detecting area, but is based on the entry point of the target to be detected into the detecting area, and at least one of the target to be tested enters The entry point location of the neighbor node of the sensor node is determined. Then, in the prior art, if the sensor node wants to determine the motion speed of the target to be tested in the detection area, the at least one neighbor node needs to send the location information of the entry point of the object to be tested to the neighbor node to the sensor node, which is Increasing the amount of data transmitted in the sensor network increases the power consumption of the sensor network. In the embodiment of the present invention, the sensor node determines the entry point position of the target to be tested to enter the detection area of the sensor node, the departure point position of the detection area that has left the sensor node, and the target to enter and leave the sensor. The time difference of the node detection area determines the motion speed of the target to be tested in the self detection area. Compared with the prior art method for determining the moving speed of the target to be tested, the amount of information transmission between the sensor nodes is reduced, and the network power consumption is saved.

Further, a method for adjusting a detection frequency of a sensor node according to an embodiment of the present invention is applicable. For any sensor network, including binary sensor networks. A binary sensor means that the sensor can only send single-bit information (1 or 0) to its neighbor nodes according to the current state of the target to be measured, which has less communication and saves network power consumption. In the embodiment of the present invention, the frequency indication message and the location indication message transmitted between the sensor node and its neighbor nodes may be represented by single bit information (1 or 0), but in the prior art, the target to be tested is detected at the sensor node. When the speed of the motion in the area is required, the location of the entry point of the neighboring node detection area of the sensor node needs to be transmitted, and the location information of the entry point cannot be represented by single-bit information, which further illustrates the detection frequency provided by the embodiment of the present invention. The adjustment method can save power consumption of the sensor network.

S306. When the prediction result is no, send, to the neighbor node, a second frequency indication message indicating that the neighbor node performs detection by using a low detection frequency.

Embodiment 2:

5 is a flowchart of a method for adjusting a detection frequency of a sensor node on a receiving frequency indication message side corresponding to a detection frequency adjustment method of a sensor node as a transmission frequency indication message side provided in the first embodiment, As shown in FIG. 5, the following steps are specifically included:

S501. The sensor node receives a first frequency indication message sent by a neighbor node of the sensor node to indicate that the sensor node uses a high detection frequency for detecting.

In this step, the first frequency indication message is a frequency indication message sent by the neighboring node to the detection area of the neighboring node detected by the neighboring node, and sent to the sensor node.

5502. Perform detection by using the above high detection frequency.

The sensor node receives the location indication message that the to-be-detected target is not located in the detection area of the neighboring node, and the neighboring node sends the neighboring node to the detection area of the neighboring node. A second frequency indication message indicating that the sensor node is probing with a low detection frequency.

In this step, the second frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node, and sends the detection area to the sensor node. Frequency indication message, or for the neighbor node mentioned above A frequency indication message sent to the sensor node after the preset time length has elapsed since the time when the target is separated from the detection area of the sensor node.

S504. Determine a duration between the time when the location indication message is received and the time when the second frequency indication message is received is less than a duration threshold, and the time when the location indication message is received and the time when the second frequency indication message is received The first frequency indication message sent by other neighboring nodes is not received, and the target to be tested is detected by using a low detection frequency.

Further, when the neighboring node detects that the target to be tested is away from the detection area of the neighboring node, the location indication message may be sent to the sensor node, and when the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, And predicting that the target to be tested does not enter the detection area of the sensor node, and sending the location indication message and the second frequency indication message to the sensor node, in which case the location indication message and the second frequency are The indication message may be encapsulated and sent in the same message, or may be sent separately into two messages. When the two messages are sent separately, the time interval for sending the two messages is very small, and the sending is in no order, and the location indication message may be sent first. Then, the second frequency indication message is sent, and the second frequency indication message may be sent first and then the location indication message is sent. The time interval between the location indication message and the second frequency indication message received by the sensor node is very small, and there is no order.

Further, when the neighboring node detects that the target to be tested leaves the detection area of the neighbor node, but cannot immediately predict whether the target to be tested does not enter the detection area of the sensor node, the foregoing node may send the foregoing to the sensor node. a position indication message, after the preset time length elapses from the time when the target to be tested leaves the detection area of the sensor node, sending the second frequency indication message to the sensor node, in which case the sensor node receives the position indication There may be a certain time interval between the message and the receiving time of the second frequency indication message. Therefore, the sensor node is required to determine that the time interval is less than the duration threshold, and the time when the location indication message is received is received. Between the moments of the second frequency indication message, the first frequency indication message sent by the other neighboring nodes is not received, and the target to be tested is detected by using the low detection frequency. And if the second location indication message is received at the time of receiving the location indication message Between the moments, when the first frequency indication message sent by the other neighboring node is received, the target to be tested is detected by using a high detection frequency.

Further, the high detection frequency is higher than the low detection frequency.

Embodiment 3:

FIG. 6 is a flowchart of a method for adjusting a detection frequency of a sensor node as a transmission frequency indication message side according to Embodiment 3, and the specific steps are as follows:

5601. The sensor node detects that the target to be tested leaves the detection area of the sensor node.

S602. Determine, according to the entry point position and the departure point position of the detection area of the sensor node, the motion vector of the motion direction of the object to be tested.

Further, the following steps may be used to determine the position of the object to be tested that is currently at the exit point of the detection area of the sensor node:

Step 1: When detecting that the target to be tested leaves the detection area of the sensor node, respectively obtain a preset boundary between the sensor node and each neighbor node thereof, where the sensor node and the neighbor node The intersection boundary is a boundary of the detection area of the sensor node in a boundary between the detection area of the sensor node and the detection area of the neighbor node;

Further, the intersection boundary between the sensor node and each neighbor node in step 1 and the location information of each neighbor node may be pre-determined and stored when the sensor node is initialized, thereby avoiding the process of detecting the target to be tested. The amount of data transmitted during the determination of each intersection boundary is large, and the wireless sensor network resources are consumed.

Step 2: Determine, from each of the neighbor nodes, each first neighbor node in the detection area, and determine a first overlapping boundary of each intersection boundary between the sensor node and each of the first neighbor nodes. ;

Step 3: Determine, from each of the neighboring nodes, the second neighboring nodes that are not located in the detection area, and determine an intersection boundary between the sensor node and each of the second neighboring nodes, and the first a second overlapping boundary of the overlapping boundary;

Step 4: determining, at the departure point position of the detection area of the sensor node, the target to be tested. a boundary range on a boundary of the detection area of the sensor node, which is a boundary other than each of the second overlapping boundaries in the first overlapping boundary;

Step 5: Determine, according to the foregoing boundary range on the boundary of the detection area of the sensor node, the position of the departure point of the detection target of the target node. In this step, it can be determined that the midpoint of the above boundary range is the position of the above-mentioned exit point.

The following is an example. Figure 7 is a schematic diagram showing the relationship between the motion trajectory of the target to be measured and the positional relationship between the sensor node and its neighbor nodes, as shown in Figure 7:

N _x (at the center of the circle at the top), N _y (at the center of the circle at the far right), and N _z (at the center of the circle at the bottom) are three sensor nodes, and the detection area of ^ is A circular detection area with a radius of R centered on O _{x , and} a detection area of N _y is a circular detection area with a radius of R centered on Ο _γ , and the detection area is centered at 0 ₂ with a radius of R Round detection area. And the detection areas of the sensor nodes N _x , N _y , and are overlapped with each other, and the three are neighbor nodes. It is assumed that the target to be measured passes the detection nodes of the sensor nodes Ν _χ , _{γ γ} , and N _z in the motion track TrackA, and the position of the departure point when the target to be detected leaves the detection area of the sensor node is point A, and the target to be tested leaves the sensor node. The position of the exit point when the detection area of N _y is point B. In this embodiment, the steps of determining the boundary of the detection area of the sensor node where the positions of points A and B are located are as follows:

The step of determining the boundary range on the boundary of the sensor node N _x detection area at the point A is as follows: Step 1. When the sensor node N _x detects that the target to be tested leaves its own detection area, respectively acquires the preset own detection area and the neighbor node N. intersecting the boundary region between the probe EO _x F _y is N _y located inside the arc corresponding to the intersection between the boundary detection area N _x detection region itself and the neighbor node is located inside the CO _x D corresponding N _z arc;

Step 2, determining a target to be measured is located within the detection area of the sensor node N _y, and located within the detection region of the sensor node N _z, determining the detection region is located inside the arc _Ν γ EO _x F corresponding to the located corresponding to CO _x D The portion of the N 々 detection area where the arc overlaps is the first overlapping boundary, that is, the arc corresponding to EO _γ and N _z corresponding to EO _x D;

Step 3. Determine the position of point A, the boundary of the boundary of the sensor node N 々 detection area Surrounding, an arc corresponding to EO _x D and located inside Ν _γ and N _z ;

Step 4: Determine the position of point A according to an arc corresponding to EO _x D and located inside N _y and N _z . For example, the position of point A may be any point on the above EO _x D arc, preferably, it may be determined as midpoint.

The step of determining the boundary range on the boundary of the sensor node N _y detecting area at point B: Step 1: When the sensor node N _y detects that the target to be tested leaves its own detection area, respectively acquires the preset own detection area and the neighbor node ^ The intersection boundary between the detection regions is an arc located inside N _x corresponding to EO _y F , and the intersection boundary between the detection region of Ny itself and the detection region of the neighbor node is an arc corresponding to GOyH and located inside N _z ;

Step 2: determining that the target to be measured is located in the detection node N 々 detection area, and determining that the arc corresponding to the interior of N _z corresponding to GOyH is the first overlapping boundary;

The step 3, determining a target to be measured is not located in the detection area of the sensor nodes ^, EO _y F is determined corresponding to the N _x inside the arc with the first overlapping boundary GOyH corresponding to the overlapping boundary between the inside of the arc N _z , that is, the arc corresponding to EO _y G is the second overlapping boundary;

Step 4, the position of point B is determined, the boundaries on the boundary detection area of the sensor node N _y, is located inside the corresponding GOyH N _z-arc corresponding to the arc EOyG addition, i.e. corresponding to the located _ΕΟ γ Η The arc inside N _Z ;

Step 5, the position of point B is determined based on the EO _y H N _z located inside the arcs corresponding, for example, the position of point B can be determined as any point on the arc EO _y H, preferably, it may be determined as the midpoint.

S603. Predict whether the target to be tested is about to enter the detection area of the neighbor node according to the location of the sensor node, the location of the neighbor node of the sensor node, and the positional relationship between the motion vectors. If yes, go to step S604; if no, go to step S605.

Further, this step can be implemented by the following steps:

Step 3: When an angle between the direction vector and the motion vector is greater than a preset angle threshold, Predicting that the target to be tested is not going to enter the detection area of the neighbor node;

Step 4: When the angle between the direction vector and the motion vector is not greater than a preset angle threshold, predict that the target to be tested is about to enter the detection area of the neighbor node.

Further, the preset angle threshold may be 90 degrees, or slightly greater than 90 degrees, or slightly less than 90 degrees.

5604. When the prediction result is yes, send, to the neighbor node, a first frequency indication message indicating that the neighbor node uses the high detection frequency for detecting; the process ends.

S605, when the prediction result is no, send, to the neighbor node, a second frequency indication message indicating that the neighbor node detects by using a low detection frequency.

Further, when the prediction result is no, the neighbor node may be determined to be a non-edge sensor node, where the non-edge sensor node is a sensor node that is not located at the edge of the wireless sensor network to which the sensor node belongs. The edge node can always keep detecting with a high detection frequency. Therefore, when the prediction result is no, even if the second frequency indication message is sent to the neighbor node as the edge sensor node, the edge sensor node may not lower its own detection frequency.

Further, the location of the entry point of the target to be tested and the location of the exit point of the detection area of the sensor node may be sent to the designated device, where the specified device is configured to determine according to the location of the entry point and the location of the exit point. The trajectory of the target to be tested.

Embodiment 4:

FIG. 8 is a flowchart of a method for adjusting a detection frequency of a sensor node on a receiving frequency indication message side corresponding to a detection frequency adjustment method of a sensor node as a transmission frequency indication message side provided in Embodiment 3, As shown in FIG. 8, the following steps are specifically included:

S801, determining that the sensor node receives the first frequency indication message sent by the neighboring node of the sensor node indicating that the sensor node uses a high detection frequency for detection; if yes, proceeding to step S802; if not, proceeding to step S803;

In this step, the first frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested is about to enter the detection area of the sensor node. Domain, a frequency indication message sent to the above sensor node.

S802. Detecting the object to be tested by using a high detection frequency.

Further, when the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, the target to be tested may have entered the detection area of the sensor node, and if the neighboring node moves according to the predicted target to be tested Trending, sending the first frequency indication message to the sensor node, so that the sensor node may detect when the first frequency indication message is received by using a high detection frequency (because the target to be tested has entered the detection area of the sensor node), Therefore, the method may further include the step of: detecting, by the sensor node, the detection target into the detection area of the sensor node, and detecting the target to be tested by using the high detection frequency.

S803. When the received frequency indication message is a second frequency indication message indicating that the sensor node uses a low detection frequency for detecting, the target to be tested is detected by using the low detection frequency.

Further, the foregoing second frequency indication message is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node, and sends the detection area to the sensor node. Frequency indication message.

Further, in this step, before detecting with a low detection frequency, the method may further include: determining that the node is a non-edge sensor node; wherein, the non-edge sensor node is a sensor node that is not located at an edge of the wireless sensor network to which the sensor node belongs. The sensor node located at the edge of the wireless sensor network can be set to always detect at a high detection frequency, so when the second frequency indication message sent by its neighbor node is received, the detection frequency is not lowered.

Based on the same inventive concept, an embodiment of the present invention further provides a detection frequency adjustment system and a sensor of a sensor node. The principle of the problem solved by the system and the sensor is similar to the detection frequency adjustment method of the foregoing sensor node. For the implementation of the sensor, reference may be made to the implementation of the foregoing method, and the repeated description will not be repeated.

A method for adjusting a detection frequency of a sensor node according to the above embodiment of the present invention is applied to each sensor node in a sensor network as a side of a transmission frequency indication message, and correspondingly, The embodiment of the present invention further provides a sensor 901, which is shown in FIG. 9. The specific structure includes: a determining module 902, configured to detect a target to leave the sensor node when detecting the target to be tested, according to the target to be tested. Determining a motion vector of a moving direction of the object to be tested in an attack point position and an exit point position in a detection area of the sensor node in a sub-detection period;

The prediction module 903 is configured to predict, according to the location of the sensor node, the location of the neighbor node of the sensor node, and the positional relationship between the motion vectors determined by the determining module 902, whether the target to be tested is to enter the neighboring node. The region obtains the predicted results;

The sending module 904 is configured to send, according to the prediction result predicted by the prediction module 903, a frequency indication message to the neighboring node, where the frequency indication message indicates that the neighboring node performs detection by using a high detection frequency or a low detection frequency.

Further, the sending module 904 is further configured to: when detecting that the object to be tested enters a detection area of the sensor node, the sensor node sends a first frequency to the neighbor node that indicates that the neighbor node uses the high detection frequency to detect Indication message

The foregoing sending module 904 is specifically configured to: when the prediction result predicted by the prediction module is negative, send, to the neighboring node, a second frequency indication message indicating that the neighboring node detects by using a low detection frequency.

Further, the foregoing sending module 904 is specifically configured to: when the prediction result predicted by the prediction module 903 is yes, send, to the neighboring node, a first frequency indication message indicating that the neighboring node uses a high detection frequency for detecting; when the prediction module 903 predicts If the prediction result is no, the second neighboring node sends a second frequency indication message indicating that the neighboring node uses the low detection frequency for detecting.

Further, the foregoing prediction module 903 is specifically configured to acquire a direction vector of a position of the foregoing sensor node that is located at a position of the neighboring node, and determine an angle between the direction vector and the motion vector determined by the determining module 902; When the angle between the direction vector and the motion vector determined by the determining module 902 is greater than the preset angle threshold, predicting that the target to be tested is not to enter the detection area of the neighbor node; when the direction vector is determined by the determining module 902 When the angle between the above motion vectors is not greater than the preset angle threshold, it is predicted that the target to be tested is to enter the neighbor The detection area of the node.

Further, the foregoing prediction module 903 is specifically configured to acquire a direction vector of a position of the foregoing sensor node that is located at a position of the neighboring node, and determine an angle between the direction vector and the motion vector determined by the determining module 902; When the angle between the direction vector and the motion vector determined by the determining module 902 is greater than the preset angle threshold, predicting that the target to be tested is not to enter the detection area of the neighbor node; when the direction vector is determined by the determining module 902 When the angle between the motion vectors is not greater than the preset angle threshold, the target to be tested does not enter the sensor when it is determined that the preset time is elapsed from the time when the target to be tested leaves the detection area of the sensor node. The detection area of the node predicts that the target to be tested is not going to enter the detection area of the neighbor node.

Further, the foregoing prediction module 903 is specifically configured to determine the preset duration according to the following manner: determining, according to the entry point position of the detection target area of the sensor node and the leaving point position, the target to be tested is The moving distance in the detecting area of the sensor node; determining the waiting time according to the entry time of the detecting area of the current target to enter the sensor node, and the leaving time of the detecting area of the target to be tested from the sensor node a motion time of the target in the detection area of the sensor node; determining a motion speed of the target to be measured in the detection area of the sensor node according to the motion distance and the motion time; determining the preset duration as a preset coefficient and the foregoing The ratio of the product of the radius of the detection area of the sensor node to the speed of motion described above.

Further, the determining module 902 is specifically configured to determine, by using the following manner, the leaving point position of the detecting target in the detecting area of the sensor node:

When detecting that the target to be tested leaves the detection area of the sensor node, respectively acquiring an intersection boundary between the preset sensor node and each neighbor node thereof, wherein an intersection boundary between the sensor node and the neighbor node is the foregoing a boundary of the detection area of the sensor node in a boundary between a detection area of the sensor node and a detection area of the neighbor node; and determining, from each of the neighbor nodes, each first neighbor node in which the object to be tested is located in the detection area And confirm the above a first overlapping boundary of each intersection boundary between the sensor node and each of the first neighboring nodes; determining, from each of the neighboring nodes, each second neighboring node that is not located in the detecting area, and determining the foregoing a second overlapping boundary between the intersection of the sensor node and each of the second neighboring nodes and the first overlapping boundary; determining a position of the leaving point of the detecting area of the object to be tested and passing through the sensor node, at the sensor node The boundary range on the boundary of the detection area is a boundary other than each of the second overlapping boundaries in the first overlapping boundary; determining the target to be tested according to the boundary range on the boundary of the detection area of the sensor node At the exit point position of the detection area of the sensor node described above.

Further, the foregoing prediction module 903 is specifically configured to determine, according to the entry point position and the exit point position of the detection area of the sensor node, the motion of the object to be tested in the detection area of the sensor node. Determining the entry time of the detection area of the above-mentioned sensor node according to the above-mentioned object to be tested, and the departure time of the detection area of the object to be tested from the sensor node, determining the detection area of the object to be tested at the sensor node The motion time within the motion time; determining the motion speed of the object to be tested in the detection area of the sensor node according to the motion distance and the motion time.

According to the foregoing embodiment of the present invention, a method for adjusting a detection frequency of a sensor node is applied to each sensor node in the sensor network as a side of receiving a frequency indication message. Accordingly, an embodiment of the present invention further provides a The sensor 1001 has a schematic structural diagram as shown in FIG. 10, and specifically includes:

The receiving module 1002 is configured to receive, by the sensor node, a frequency indication message sent by the neighbor node of the sensor node, where the frequency indication message is based on a location of the sensor node, a location of a neighbor node of the sensor node, and a motion vector of the target to be tested. Positional relationship determination;

The frequency adjustment module 1003 is configured to: when the frequency indication message received by the receiving module 1002 is a first frequency indication message indicating that the sensor node uses a high detection frequency for detecting, use the high detection frequency to perform the target to be tested. Detecting; the frequency indication message received by the receiving module is a second frequency indication indicating that the sensor node uses a low detection frequency for detecting In the message, the target to be tested is detected by using the low detection frequency.

Further, the first frequency indication message received by the receiving module 1002 is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested is about to enter the detection area of the sensor node, a frequency indication message sent by the sensor node;

The frequency adjustment module 1003 is further configured to detect the target to be tested by detecting the target to be tested and entering the detection area of the sensor node by using the high detection frequency.

The second frequency indication message received by the receiving module 1002 is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node. The frequency indication message sent by the above sensor node.

Further, the first frequency indication message received by the receiving module 1002 is a frequency indication message sent by the neighboring node to the detection area of the neighboring node detected by the neighboring node, and sent to the sensor node;

The second frequency indication message received by the receiving module 1002 is that the neighboring node detects that the target to be tested leaves the detection area of the neighboring node, and predicts that the target to be tested does not enter the detection area of the sensor node. a frequency indication message sent by the sensor node, or a frequency indication message sent by the neighboring node to the sensor node after a predetermined period of time has elapsed since the time when the target to be tested leaves the detection area of the sensor node;

The receiving module 1002 is further configured to receive, by the neighboring node, a location indication message that is not located in the detection area of the neighboring node that is sent by the neighboring node when the detection target is removed from the detection area of the neighboring node;

The frequency adjustment module 1003 is specifically configured to be used by the receiving module 1002 to receive the foregoing frequency. When the rate indication message is a second frequency indication message indicating that the sensor node uses the low detection frequency for detecting, and the time between the time when the receiving module 1002 receives the location indication message and the time when the second frequency indication message is received If the time threshold is less than the duration, and the time when the location indication message is received and the time when the second frequency indication message is received, the first frequency indication message sent by the other neighboring node is not received, and the low detection frequency is used to treat the to The target is detected.

A detection frequency adjustment system for a sensor node according to an embodiment of the present invention includes: a first sensor node, which is a second sensor node of a neighbor node of the first sensor node, where: the first sensor node is used to detect The target to be tested is separated from the detection area of the first sensor node, and the moving direction of the target to be tested is determined according to the position of the entry point and the position of the exit point in the detection area of the first sensor node in the current detection period. And determining, according to the position of the first sensor node, the position of the second sensor node, and the positional relationship between the motion vectors, whether the target to be tested is to enter the detection area of the second sensor node to obtain a prediction result. Transmitting, according to the foregoing prediction result, a frequency indication message to the second sensor node, where the frequency indication message indicates that the second sensor node detects by using a high detection frequency or a low detection frequency;

The second sensor node is configured to receive the frequency indication message sent by the first sensor node, and when the received frequency indication message is a first frequency indication message that is used by the second sensor node to detect by using a high detection frequency, The high detection frequency is used to detect the target to be tested; when the received frequency indication message is a second frequency indication message indicating that the second sensor node uses a low detection frequency for detecting, the low detection frequency is used to The target is detected.

A method, system and sensor for detecting a detection frequency of a sensor node according to an embodiment of the present invention, when detecting a detection target leaving a detection area of a sensor node, according to the object to be tested, the detection area of the sensor node in the current detection period Determining the motion vector of the moving direction of the object to be tested, and determining the position according to the position of the sensor node, the position of the neighbor node of the sensor node, and the positional relationship between the motion vectors Whether the target to be tested is going to enter The detection area of the neighboring node obtains a prediction result. According to the prediction result, a frequency indication message is sent to the neighboring node, where the frequency indication message indicates that the neighboring node performs detection by using a high detection frequency or a low detection frequency. Correspondingly, the sensor node can receive the frequency indication message sent by the neighboring node; when the received frequency indication message is the first frequency indication message indicating that the sensor node uses the high detection frequency for detecting, the target is to be measured with a high detection frequency. Performing detection; when the received frequency indication message is a second frequency indication message indicating that the sensor node uses a low detection frequency for detection, the target to be measured is detected by using a low detection frequency. The sensor node determines a neighboring node to be detected by using a high detection frequency or a low detection frequency according to the motion trend of the target to be measured in the detection area, and sends a corresponding frequency indication message to the neighbor node, and the neighbor node receives the corresponding frequency indication message. The frequency indication message is detected by using a high detection frequency or a low detection frequency according to its own situation. Compared with the prior art, all sensor nodes in the wireless sensor network reduce the overall power consumption of the wireless sensor network in any case by using a fixed detection frequency to detect the target to be measured.

Through the description of the above embodiments, those skilled in the art can clearly understand that the embodiments of the present invention can be implemented by hardware, or can be implemented by means of software plus necessary general hardware platform. Based on the understanding, the technical solution of the embodiment of the present invention may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (which may be a CD-ROM, a USB flash drive, a mobile hard disk, etc.). A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments of the present invention.

Those skilled in the art will appreciate that the drawings are only a schematic representation of a preferred embodiment, and that the modules or processes in the drawings are not necessarily required to practice the invention.

Those skilled in the art can understand that the modules in the apparatus in the embodiments may be distributed in the apparatus of the embodiment according to the description of the embodiments, or the corresponding changes may be located in one or more apparatuses different from the embodiment. The modules of the above embodiments may be combined into one module, or may be further split into a plurality of sub-modules.

The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments. The spirit and scope of the Ming. Thus, it is intended that the present invention cover the modifications and the modifications of the invention

Claims

claims

1. A method for adjusting the detection frequency of sensor nodes, which is characterized by including:

When it is detected that the target to be measured leaves the detection area of the sensor node, the movement of the target to be measured is determined based on the entry point position and exit point position of the target to be measured within the detection area of the sensor node during this detection period. direction of motion vector;

According to the position relationship between the position of the sensor node, the position of the neighbor node of the sensor node, and the motion vector, predict whether the target to be measured will enter the detection area of the neighbor node to obtain a prediction result;

According to the prediction result, a frequency indication message is sent to the neighbor node, and the frequency indication message instructs the neighbor node to use a high detection frequency or a low detection frequency for detection.

2. The method according to claim 1, characterized in that, before determining the motion vector of the motion direction of the target to be measured, it further includes:

When it is detected that the target to be measured enters the detection area of the sensor node, the sensor node sends a first frequency indication message to its neighbor node instructing the neighbor node to use the high detection frequency for detection;

According to the prediction result, sending a frequency indication message to the neighbor node includes:

When the prediction result is negative, a second frequency indication message is sent to the neighbor node instructing the neighbor node to use a low detection frequency for detection.

3. The method according to claim 1, characterized in that, according to the prediction result, sending a frequency indication message to the neighbor node, specifically including:

When the prediction result is yes, sending a first frequency indication message to the neighbor node instructing the neighbor node to use a high detection frequency for detection;

4. The method according to claim 1, characterized in that, according to the position of the sensor node, The position relationship between the neighbor nodes of the sensor node and the motion vector is used to predict whether the target to be measured will enter the detection area of the neighbor node to obtain the prediction result, which specifically includes:

Obtain a preset direction vector pointing from the position of the sensor node to the position of the neighbor node; Determine the angle between the direction vector and the motion vector;

When the angle between the direction vector and the motion vector is greater than the preset angle threshold, it is predicted that the target to be measured will not enter the detection area of the neighbor node;

When the angle between the direction vector and the motion vector is not greater than the preset angle threshold, it is predicted that the target to be measured will enter the detection area of the neighbor node.

5. The method according to claim 1 or 2, characterized in that, according to the position of the sensor node, the position of the neighbor node of the sensor node, and the position relationship between the motion vectors, predict the Whether the target to be measured is going to enter the detection area of the neighbor node is determined to obtain the prediction result, which specifically includes:

When the angle between the direction vector and the motion vector is not greater than the preset angle threshold, when it is determined that within a preset time period elapsed from the moment when the target to be measured leaves the detection area of the sensor node, The target to be measured has not entered the detection area of the sensor node, and it is predicted that the target to be measured will not enter the detection area of the neighbor node.

6. The method of claim 5, wherein the preset duration is determined in the following manner:

According to the entry point position and the exit point position of the target to be measured in the detection area of the sensor node this time, determine the movement distance of the target to be measured in the detection area of the sensor node; According to the entry time of the target to be measured entering the detection area of the sensor node this time, and the departure time of the target to be measured leaving the detection area of the sensor node this time, it is determined that the target to be measured is in the sensor node The movement time of the node within the detection area;

Determine the movement speed of the target to be measured in the detection area of the sensor node according to the movement distance and the movement time;

The preset duration is determined as the ratio of the product of the preset coefficient and the radius of the detection area of the sensor node to the movement speed.

7. The method according to claim 1, characterized in that the following method is used to determine the departure point position of the target to be measured in the detection area of the sensor node:

When it is detected that the target to be measured leaves the detection area of the sensor node, the preset intersection boundaries between the sensor node and its neighbor nodes are respectively obtained, wherein: The intersection boundary is the boundary of the detection area of the sensor node in the boundary of the overlapping area of the detection area of the sensor node and the detection area of the neighbor node;

From each of the neighbor nodes, determine each first neighbor node in which the target to be measured is located in its detection area, and determine the first overlap of each intersection boundary between the sensor node and each of the first neighbor nodes. border;

From each of the neighbor nodes, determine each second neighbor node in which the target to be measured is not located in its detection area, and determine the intersection boundary between the sensor node and each second neighbor node and the said a second overlapping boundary of the first overlapping boundary;

Determine the departure point position of the target to be measured passing through the detection area of the sensor node this time. The boundary range on the boundary of the detection area of the sensor node is the first overlapping boundary except each of the second Boundaries beyond overlapping boundaries;

According to the boundary range on the boundary of the detection area of the sensor node, the departure point position of the target to be measured in the detection area of the sensor node is determined.

8. The method according to any one of claims 1 to 4, further comprising:

According to the entry point position of the target to be measured in the detection area of the sensor node this time and the departure point position to determine the movement distance of the target to be measured within the detection area of the sensor node;

According to the entry time of the target to be measured entering the detection area of the sensor node this time, and the departure time of the target to be measured leaving the detection area of the sensor node this time, it is determined that the target to be measured is in the sensor node The movement time of the node within the detection area;

The movement speed of the target to be measured in the detection area of the sensor node is determined based on the movement distance and the movement time.

9. A method for adjusting the detection frequency of sensor nodes, which is characterized by including:

The sensor node receives a frequency indication message sent by a neighbor node of the sensor node. The frequency indication message is based on the position of the sensor node, the position of the neighbor node of the sensor node, and the motion vector of the target to be measured. The positional relationship is determined;

When the received frequency indication message is a first frequency indication message instructing the sensor node to use a high detection frequency for detection, using the high detection frequency to detect the target to be measured;

When the received frequency indication message is a second frequency indication message instructing the sensor node to use a low detection frequency for detection, the low detection frequency is used to detect the target to be measured.

10. The method of claim 9, wherein the first frequency indication message is when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured is about to Entering the detection area of the sensor node, sending a frequency indication message to the sensor node;

The method also includes:

When it is detected that the target to be measured enters the detection area of the sensor node, the high detection frequency is used to detect the target to be measured.

11. The method of claim 9, wherein the first frequency indication message is when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured leaves the detection area of the neighbor node. The target is about to enter the detection area of the sensor node, and a frequency indication message is sent to the sensor node;

The second frequency indication message is when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured will not enter the detection area of the sensor node, to the neighbor node. The frequency indication message sent by the sensor node.

12. The method of claim 9, wherein the first frequency indication message is a frequency indication sent to the sensor node when the neighbor node detects that the target to be measured enters the detection area of the neighbor node. information;

The second frequency indication message is when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured will not enter the detection area of the sensor node, to the neighbor node. The frequency indication message sent by the sensor node, or the frequency indication message sent by the neighbor node to the sensor node after a preset time period has elapsed since the time when the target to be measured leaves the detection area of the sensor node;

The method also includes:

Receive a location indication message that the target to be measured is not located within the detection area of the neighbor node and is sent when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node; when the received frequency When the indication message is a second frequency indication message instructing the sensor node to use a low detection frequency for detection, the low detection frequency is used to detect the target to be measured, specifically:

When the received frequency indication message is a second frequency indication message instructing the sensor node to use a low detection frequency for detection, and the time when the location indication message is received is the same as the time when the second frequency indication message is received. The duration between moments is less than the duration threshold, and the first frequency indication message sent by other neighbor nodes is not received between the moment when the location indication message is received and the moment when the second frequency indication message is received, using the The target to be measured is detected using the low detection frequency.

13. A sensor, characterized in that it includes:

Determining module, used when detecting that the target to be measured leaves the detection area of the sensor node, according to the The entry point position and exit point position of the target to be measured in the detection area of the sensor node during this detection period determine the motion vector of the movement direction of the target to be measured;

A prediction module configured to predict whether the target to be measured will enter the neighbor based on the position of the sensor node, the position of the neighbor node of the sensor node, and the positional relationship between the motion vectors determined by the determination module. The detection area of the node obtains the prediction result;

A sending module, configured to send a frequency indication message to the neighbor node according to the prediction result predicted by the prediction module, where the frequency indication message instructs the neighbor node to use a high detection frequency or a low detection frequency for detection.

14. The sensor according to claim 13, wherein the sending module is further configured to: when detecting that the target to be measured enters the detection area of the sensor node, the sensor node sends a message to its neighbor node. Send a first frequency indication message instructing the neighbor node to use the high detection frequency for detection;

The sending module is specifically configured to send a second frequency indication message to the neighbor node instructing the neighbor node to use a low detection frequency for detection when the prediction result predicted by the prediction module is no.

15. The sensor according to claim 13, wherein the sending module is specifically configured to send an instruction to the neighbor node to use a high detection frequency when the prediction result predicted by the prediction module is yes. The first frequency indication message for detection; when the prediction result predicted by the prediction module is negative, send a second frequency indication message to the neighbor node instructing the neighbor node to use a low detection frequency for detection.

16. The sensor according to claim 13, wherein the prediction module is specifically configured to obtain a preset direction vector from the position of the sensor node to the position of the neighbor node; determine the relationship between the direction vector and the position of the neighbor node. The angle between the motion vector determined by the determination module; When the angle between the direction vector and the motion vector determined by the determination module is greater than a preset angle threshold, it is predicted that the target to be measured is not is about to enter the detection area of the neighbor node; when the angle between the direction vector and the motion vector determined by the determination module is not greater than the preset angle threshold, predict that the target to be measured is about to enter the neighbor The detection area of the node.

17. The sensor according to claim 13 or 14, wherein the prediction module is specifically configured to obtain a preset direction vector from which the position of the sensor node points to the position of the neighbor node; determine the direction vector. The angle between the direction vector and the motion vector determined by the determination module; when the angle between the direction vector and the motion vector determined by the determination module is greater than a preset angle threshold, predict the to-be-tested The target is not about to enter the detection area of the neighbor node; when the angle between the direction vector and the motion vector determined by the determination module is not greater than the preset angle threshold, when it is determined to leave the target to be measured Within a preset time period that elapses from the detection area of the sensor node, the target to be measured does not enter the detection area of the sensor node, and it is predicted that the target to be measured will not enter the detection area of the neighbor node.

18. The sensor of claim 17, wherein the prediction module is specifically configured to determine the preset duration in the following manner:

According to the entry point position and the exit point position of the target to be measured in the detection area of the sensor node this time, the movement distance of the target to be measured in the detection area of the sensor node is determined; The entry time of the target to be measured entering the detection area of the sensor node this time, and the departure time of the target to be measured leaving the detection area of the sensor node this time, determine the location of the target to be measured at the sensor node. Movement time in the detection area; Determine the movement speed of the target to be measured in the detection area of the sensor node based on the movement distance and the movement time; Determine the preset time length as the preset coefficient and the sensor The ratio of the product of the node's detection area radius to the movement speed.

19. The sensor according to claim 13, wherein the determination module is specifically configured to determine the departure point position of the target to be measured in the detection area of the sensor node in the following manner:

When it is detected that the target to be measured leaves the detection area of the sensor node, the preset intersection boundaries between the sensor node and its neighbor nodes are respectively obtained, wherein: The intersection boundary is the boundary of the detection area of the sensor node in the boundary of the overlapping area of the detection area of the sensor node and the detection area of the neighbor node; from each neighbor Among the nodes, determine each first neighbor node where the target to be measured is located in its detection area, and determine the first overlapping boundary of each intersection boundary between the sensor node and each first neighbor node; from the Among each neighbor node, determine each second neighbor node in which the target to be measured is not located in its detection area, and determine the intersection boundary between the sensor node and each second neighbor node and the first overlap respectively. The second overlapping boundary of the boundary; Determine the departure point position of the target to be measured passing through the detection area of the sensor node this time, and the boundary range on the boundary of the detection area of the sensor node is the first overlapping boundary Boundaries other than each of the second overlapping boundaries; Determine the exit point of the target to be measured in the detection area of the sensor node according to the boundary range on the boundary of the detection area of the sensor node. Location.

20. The sensor according to any one of claims 13 to 16, wherein the prediction module is specifically configured to determine the entry point position and position of the target to be measured in the detection area of the sensor node this time. The departure point position determines the movement distance of the target to be measured in the detection area of the sensor node; according to the entry time of the target to be measured entering the detection area of the sensor node, and the The departure time of the target leaving the detection area of the sensor node this time, determine the movement time of the target to be measured in the detection area of the sensor node; determine the target to be measured based on the movement distance and the movement time Movement speed within the detection area of the sensor node.

21. A sensor, characterized in that it includes:

A receiving module, configured for a sensor node to receive a frequency indication message sent by a neighbor node of the sensor node, where the frequency indication message is based on the location of the sensor node, the location of the neighbor node of the sensor node, and the target to be measured. The positional relationship between the motion vectors is determined;

a frequency adjustment module, configured to use the high detection frequency to adjust the frequency to be measured when the frequency indication message received by the receiving module is a first frequency indication message instructing the sensor node to use a high detection frequency for detection. The target is detected; when the frequency indication message received by the receiving module is a second frequency indication message instructing the sensor node to use a low detection frequency for detection, use the low detection frequency to perform detection on the target to be measured. detection.

22. The sensor according to claim 21, characterized in that: the receiving module receives The first frequency indication message is sent to the sensor node when the neighbor node detects that the target to be measured leaves the detection area of the neighbor node and predicts that the target to be measured will enter the detection area of the sensor node. frequency indication message;

The frequency adjustment module is also configured to use the high detection frequency to detect the target to be measured when it is detected that the target to be measured enters the detection area of the sensor node.

23. The sensor according to claim 21, wherein the first frequency indication message received by the receiving module is that the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts When the target to be measured is about to enter the detection area of the sensor node, send a frequency indication message to the sensor node;

The second frequency indication message received by the receiving module is that the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured will not enter the sensor. The detection area of the node, and the frequency indication message sent to the sensor node.

24. The sensor according to claim 21, wherein the first frequency indication message received by the receiving module indicates that the neighbor node detects that the target to be measured enters the detection area of the neighbor node, and sends the signal to the neighbor node. The frequency indication message sent by the sensor node;

The second frequency indication message received by the receiving module is that the neighbor node detects that the target to be measured leaves the detection area of the neighbor node, and predicts that the target to be measured will not enter the sensor. The detection area of the node, the frequency indication message sent to the sensor node, or the neighbor node sends a message to the sensor node after a preset time period has elapsed since the time when the target to be measured leaves the detection area of the sensor node. Frequency indication messages sent;

The receiving module is also configured to receive a location indication message sent by the neighbor node when it detects that the target to be measured leaves the detection area of the neighbor node, indicating that the target to be measured is not located in the detection area of the neighbor node. ;

The frequency adjustment module is specifically used when the frequency indication message received by the receiving module is a second frequency indication message instructing the sensor node to use a low detection frequency for detection, and the receiving module receives the The time when the position indication message is received and the second frequency indication message is received The duration between the moments is less than the duration threshold, and the first frequency indication message sent by other neighbor nodes is not received between the moment when the location indication message is received and the moment when the second frequency indication message is received, adopt The low detection frequency detects the target to be measured.

25. A detection frequency adjustment system for sensor nodes, characterized in that it includes: a first sensor node, a second sensor node that is a neighbor node of the first sensor node, wherein:

The first sensor node is configured to, when detecting that the target to be measured leaves the detection area of the first sensor node, based on the entry point of the target to be measured within the detection area of the first sensor node during this detection period. position and departure point position, determine the motion vector of the motion direction of the target to be measured; predict according to the position relationship between the position of the first sensor node, the position of the second sensor node, and the motion vector. Whether the target to be measured is going to enter the detection area of the second sensor node is predicted to obtain a prediction result; according to the prediction result, a frequency indication message is sent to the second sensor node, and the frequency indication message indicates the second sensor Nodes use high detection frequency or low detection frequency for detection;

The second sensor node is configured to receive a frequency indication message sent by the first sensor node; when the received frequency indication message is a first frequency indication message instructing the second sensor node to use a high detection frequency for detection. When the high detection frequency is used to detect the target to be measured; when the received frequency indication message is a second frequency indication message instructing the second sensor node to use a low detection frequency for detection, the frequency indication message is used. The target to be measured is detected using the low detection frequency.