KR101465120B1 - System and Method for data collecting in wireless sensor network - Google Patents

Abstract

The present invention relates to an apparatus and a method for applying data collection in a wireless sensor network, which increase energy efficiency and reduce data collection time by applying B-MAC+ and XY-MAC to downlink traffic and uplink traffic respectively in a data collection tree. According to the present invention, an MAC layer is configured to include: a packet interpreter that interprets a data packet received through the transceiver and reception part of a physical layer; a hybrid MAC operation control module that performs traffic analysis and node analysis for the packet interpreted by the packet interpreter, analyzes an MAC protocol, and applies a preamble sampling technique of different protocols to downlink traffic and uplink traffic respectively in a data collection tree; and a packet generator that generates a packet through the control of the hybrid MAC operation control module.

Description

TECHNICAL FIELD [0001] The present invention relates to an apparatus and a method for collecting data in a wireless sensor network,

The present invention relates to data communication in a wireless sensor network. More particularly, in the data collection tree, preamble sampling techniques of different protocols are respectively applied to the downlink traffic and the uplink traffic to increase the energy efficiency and reduce the data collection time And more particularly, to a device and method for data collection in a wireless sensor network.

Wireless sensor networks consist of sensor nodes that use limited energy sources such as batteries. These sensor nodes basically have to guarantee a lifetime of several months to several years and at the same time, it is difficult to recharge and replace due to battery consumption, so it is most important to manage energy efficiently.

Since wireless sensor networks have low data generation rate, it is unnecessary for the sensor node to keep the idle listening for intermittent data communication, which may unnecessarily use the radio and consume energy.

In particular, energy consumption in sensor nodes is mostly due to the use of radio for data transmission and reception, so it is essential to reduce idle listening for energy efficiency. In order to minimize the energy consumption of the sensor node, the duty cycle method is mainly used in the wireless sensor network.

Duty cycle is operated in order to maximize energy efficiency. RF transceiver is divided into active state and dormant state and it is repeatedly performed to maintain the active state only when data transmission and reception are required. Otherwise, the dormant state is maintained It is energy saving technique.

These duty cycle based MAC protocols are classified into synchronous and asynchronous depending on whether the nodes constituting the network are synchronized.

Unlike synchronous protocols such as S-MAC (Sensor-MAC), which perform periodic synchronization packets to synchronize operation time among all nodes and perform communication, asynchronous protocols such as B-MAC (Berkeley-MAC) And performs communication by only synchronizing the nodes to be communicated.

As shown in FIG. 1, preamble sampling is a technique of transmitting a preamble in order to synchronize with a destination node before a transmitting node transmits actual data. The preamble sampling is advantageous in that it transmits a periodic synchronization packet and has a small overhead compared to synchronization .

However, since the preamble must be longer than the sleep interval in order to enable synchronization between any nodes, a neighboring node not participating in actual communication also has a problem of overhearing a preamble.

In B-MAC +, a preamble overhearing problem of a node not participating in communication is solved by using a short preamble packet including an address of a destination node as shown in FIG. However, like the B-MAC, there is a problem that the transmitting node repeatedly transmits a short preamble packet for a longer time than the sleep interval before transmitting the actual data to the destination node.

In order to reduce the preamble overhead in the X-MAC, an Early ACK interval is inserted between each preamble packet as shown in FIG. 3, and a destination node that recognizes the preamble packet notifies the transmitting node of the preamble packet, So that real data can be transmitted quickly.

However, in the asynchronous protocol, since the wakeup time of the receiving node may exist within the Early ACK interval of the transmitting node, the receiving node must keep the idle listening for a longer time than the Early ACK interval in order to recognize the preamble packet.

This has a problem that the waiting time of the wakeup of the receiving node becomes longer than that of B-MAC + by the interval of the early ACK.

The XY-MAC uses an early termination scheme as shown in FIG. 4 to solve this problem.

Since the Early ACK interval is a reserved interval between the transmitting node and the destination node, the transmitting node can detect the status of the channel for a short period of time through the CCA (Clear Channel Assessment), and can determine whether or not an Early ACK packet of the destination node is transmitted.

Therefore, the Early Termination scheme can reduce the Early ACK interval from the receipt time of the Early ACK packet to the CCA execution time, thus reducing the waiting time of the receiving node.

In order to increase energy efficiency, which is the most important consideration in wireless sensor networks, each protocol proposes a technique for minimizing the energy consumption of a transmitting node or a receiving node in 1: 1 communication. However, in real environment, communication type such as broadcasting to sensor node or convergecating to collection node is dominant rather than 1: 1 communication between sensor nodes.

In addition, since wireless sensor networks are used in various fields such as situation information request and event detection, various design methods of MAC layer should be studied according to differences in energy efficiency and application requirements.

In addition, D-MAC (Dynamic-MAC) is proposed to provide high energy efficiency and low latency as a representative protocol for event transmission applications. As shown in FIG. 5, each node follows a staggered schedule method of sequentially waking up according to a predetermined depth in the data collection tree, receiving data from its child node, and then transmitting data to the parent node immediately.

On the other hand, the data communication of the data collection application is performed by the information request of the periodic collection node and the response of the sensor node accordingly as shown in FIG.

Therefore, it is necessary to design a new MAC layer considering bidirectional communication traffic, unlike the event transmission application that considers only unidirectional communication traffic from the sensor node to the collection node.

Korean Patent Publication No. 10-2007-0072443 Korean Patent Publication No. 10-2009-0090767

The present invention solves the problem of the data collection process in the conventional wireless sensor network. The present invention applies a different preamble sampling scheme to downlink traffic and uplink traffic in the data collection tree, And to reduce the data collection time while increasing the size of the wireless sensor network.

The present invention operates as B-MAC + in the broadcasting type traffic in the downlink direction in the data collection tree and as XY-MAC in the convergecasting type traffic in the uplink direction And an object of the present invention is to provide an apparatus and method for data collection in a wireless sensor network that can reduce data collection time while improving energy efficiency.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided an apparatus for data collection in a wireless sensor network, comprising: a packet analyzer for analyzing a data packet received through a transceiver and a receiver of a physical layer; A hybrid MAC operation control module for performing node analysis and analyzing a MAC protocol to apply a preamble sampling technique of different protocols to downlink traffic and uplink traffic in a data collection tree; And a packet generator for performing a MAC function on the MAC layer.

The hybrid MAC operation control module includes a traffic analyzer for analyzing a traffic characteristic of the analyzed packet, a node analyzer for receiving node information from the network layer and performing node analysis, The MAC protocol analyzer operates as B-MAC + in the broadcasting type traffic in the downlink direction and operates as the XY-MAC in the convergecasting type traffic in the uplink direction .

The functions performed by the hybrid MAC operation control module include a sleep and wakeup function of a sensor node, a preamble packet recognition function of a receiving node, an Early ACK packet recognition function of a transmitting node, and a timing control function of each function .

The sleep and wakeup functions of the sensor node are implemented by controlling the state of the RF transceiver in the sleep state and the Rx state.

The preamble packet recognition function of the receiving node detects a preamble packet of a transmitting node by detecting a channel of a predetermined interval through a CCA (Clear Channel Assessment). If the channel is idle at a receiving node's wakeup time, It is determined that the node has not transmitted the preamble packet and the next duty cycle is performed. On the contrary, if the channel is busy, the node determines that the preamble packet has been transmitted and waits to receive the preamble packet.

The function of recognizing the Early ACK packet of the transmitting node is to detect the channel at the same time that the transmitting node transmits the preamble packet and start the Early ACK interval. If the channel is idle, the destination node transmits an Early ACK packet It is determined that the ACK packet has not been transmitted and the next preamble packet is transmitted immediately after the ACK interval is terminated. On the other hand, if the channel is busy, the destination node determines that the ACK packet has been transmitted and waits to receive the ACK packet.

The timing control function fixedly applies the CCA time for the early termination of the transmitting node and the idle listening time of the receiving node to 2 ms and 5 ms, respectively, irrespective of the data transmission rate in the XY-MAC, and B- Since the early ACK interval is not used, the idle listening is maintained only for the CCA time of 2 ms in order to recognize the preamble packet at the time of the wakeup of the receiving node, and the sleep interval is differently applied according to the requirements of the user or the characteristics of the application .

According to another aspect of the present invention, there is provided a method of data collection in a wireless sensor network, wherein a hybrid MAC protocol operation of a data collection application device in a wireless sensor network comprises: receiving a data packet received through a transceiver and a receiver of a physical layer; (B-MAC +) in the broadcasting type traffic in the downlink direction from the data collection tree, and in the convergecasting type traffic in the uplink direction as the XY-MAC And performing packet generation by the control of the hybrid MAC operation control module.

Here, the B-MAC + Phase operation of the collecting node includes a process of transmitting the preamble packet and the collection request data based on the B-MAC + to the lower node in order to propagate the data collection request.

The XY-MAC Phase operation of the collecting node is a process of waiting for a data collection response from all the lower nodes and, when recognizing the preamble packet, determining whether the node is the destination node through the address of the destination node included in the preamble packet And transmitting an Early ACK packet to the transmitting node to receive the actual data if the node is the destination node.

In the B-MAC + Phase operation of the sensor node, a normal node and a leaf node wait for a data collection request in the same manner. At this time, a process of performing a minimum idle listening according to B-MAC + and performing a duty cycle, Determining whether the node is a destination node through an address of a destination node included in a preamble packet when the packet is recognized; maintaining a sleep state for a predetermined period of time through a preamble packet number included in the preamble packet, And transmitting the preamble packet and the collection request data based on the B-MAC + to the lower node to propagate the data collection request if the node is not a leaf node.

In the XY-MAC Phase operation of the sensor node, if the node is a leaf node, it transmits the preamble packet and the collection response data based on the XY-MAC to the upper node immediately. Performing a duty cycle according to the XY-MAC in order to wait for a data collection response of the preamble packet, and if the preamble packet is recognized at the idle listening time, determining whether the preamble packet is a destination node through the address of the destination node included in the preamble packet, If the destination node is a destination node, the process of receiving the actual data by transmitting the Early ACK packet to the transmitting node, and then collecting the collected response data of the node and the lower node, and transmitting the XY- And transmitting the packet and the collection response data.

The apparatus and method for data collection in a wireless sensor network according to the present invention have the following effects.

First, B-MAC + in the broadcasting type traffic in the downlink direction from the data collection tree, and convergecasting type traffic in the uplink direction operates as XY-MAC, Efficiency can be increased.

Second, data collection time can be reduced by applying sampling protocols of different protocols to downlink traffic and uplink traffic in the data collection tree.

Third, B-MAC + and XY-MAC are applied to the communication traffic pattern of each direction and then mixed.

Fourth, in a wireless sensor network composed of sensor nodes using a limited energy source such as a battery, recharging and replacement due to battery consumption are minimized and energy can be efficiently managed.

1 to 5 are block diagrams showing an operation mechanism according to a general MAC protocol
FIG. 6 is a block diagram illustrating bidirectional communication traffic of a data collection application;
FIG. 7 shows a network configuration diagram of a tree form
8 is a diagram showing a hybrid MAC operation of a data collection application device in a wireless sensor network according to the present invention.
9 is a block diagram of a data acquisition application apparatus in a wireless sensor network according to the present invention.
10A and 10B are flowcharts showing a hybrid MAC operation of a data acquisition application device in a wireless sensor network according to the present invention.

Hereinafter, a preferred embodiment of a data acquisition application apparatus and method in a wireless sensor network according to the present invention will be described in detail.

The features and advantages of the data collection application device and method in a wireless sensor network according to the present invention will be apparent from the following detailed description of each embodiment.

FIG. 7 is a network configuration diagram of a tree form, and FIG. 8 is a configuration diagram illustrating a hybrid MAC operation of a data collection application device in a wireless sensor network according to the present invention.

The present invention operates as B-MAC + in the broadcasting type traffic in the downlink direction in the data collection tree and as XY-MAC in the convergecasting type traffic in the uplink direction To increase energy efficiency while reducing data collection time.

The purpose of a data collection application is for one collection node to collect data from multiple sensor nodes. Therefore, the data communication in the data collection application can be divided into the information request of the collection node and the response of the sensor node accordingly.

The collection node broadcasts an information request to all sensor nodes in the network distributed over a large area. This may last a single hop or multiple hops depending on the size of the network in the downlink direction.

While the response of the sensor node is convergecasted in the uplink direction towards one acquisition node. Convergecasting can also be performed with a single hop or multiple hops, depending on the network size.

Generally, in a convergecasting environment, it is advantageous for all the sensor nodes to combine their data with the data of the lower node and transmit them to the collecting node along a pre-configured path, thereby reducing the energy consumed by the data transmission.

At this time, a spanning tree or the like can be used as a connection method between the sensor nodes as shown in FIG.

As described above, the main transmission pattern of the data collection application is the communication traffic direction in the downlink direction and the uplink direction. This direction creates a new transmission pattern of data collection applications that is predictability of communication traffic.

First, it is impossible to predict whether or not the sensor node itself can generate communication traffic until the acquisition of the acquisition node. However, once the communication traffic is generated in the downlink direction, it can be predicted that the sensor node itself generates communication traffic in the uplink direction opposite to the direction.

This is because if the network is composed of multiple hops rather than a single hop and the sensor node is not a leaf node, it can determine that it exists on the communication traffic transmission path in the uplink direction generated from the lower node.

As shown in FIG. 8, the method proposed in the present invention operates as B-MAC + in the broadcasting type traffic in the downlink direction in the data collection tree, and performs convergecasting in the uplink direction. Type traffic can operate as XY-MAC to increase energy efficiency while reducing data collection time.

First, the sensor node itself can not predict the occurrence of communication traffic until the transmission request of the collection node. Therefore, the sensor node must perform its own duty cycle and wait until communication traffic in the downlink direction is generated.

In this case, the energy consumption of the sensor node occupies most of the children listening at every wakeup time and using the radio.

Therefore, B-MAC + is applied to reduce the energy consumption of the receiving node to the highest priority until communication traffic in the downlink direction is generated.

However, once the communication traffic in the downlink direction is generated, it can be predicted that the sensor node itself generates communication traffic in the uplink direction opposite to the direction. Since the communication traffic in the uplink direction is reserved, the preamble transmission interval for transmission at B-MAC + is much longer than the idle listening interval for reception at the XY-MAC from this point, It may be inefficient to keep -MAC + and operate as it is.

Therefore, after communication traffic in the downlink direction is generated, it operates as XY-MAC to reduce the energy consumption and delay time of the transmitting node.

The elements to be implemented in the data collection application apparatus and method in the wireless sensor network according to the present invention include a sleep and wakeup function of the sensor node, a preamble packet recognition function of the receiving node, and an Early ACK packet recognition function Function) and the timing control function of each of these functions.

Hereinafter, an apparatus and method for data collection in a wireless sensor network according to the present invention will be described in more detail.

FIG. 9 is a configuration diagram of a data collection application device in a wireless sensor network according to the present invention, and FIGS. 10A and 10B are flowcharts illustrating a hybrid MAC operation of a data collection application device in a wireless sensor network according to the present invention.

The data collecting application apparatus in the wireless sensor network according to the present invention includes a packet analyzer 93 for analyzing data packets received through the transceiver 91 and the receiving unit 92 of the physical layer, A hybrid MAC operation control module for performing node analysis and analyzing a MAC protocol to apply a sampling technique of different protocols to downlink traffic and uplink traffic in a data collection tree, The packet generator 95 is configured in the MAC layer.

The hybrid MAC operation control module includes a traffic analyzer 94a for analyzing traffic characteristics, a node analyzer 94b for receiving node information from the network layer and performing node analysis, A MAC protocol analyzer 94c that operates as B-MAC + in the broadcasting type traffic that proceeds in the downlink direction and operates as the XY-MAC in the convergecasting type traffic that proceeds in the uplink direction ).

The functions performed by the hybrid MAC operation control module are as follows: (A) a sleep and wakeup function of a sensor node; (B) a preamble packet recognition function of a receiving node; (C) (D) a timing control function of each of these functions.

(A) In case of the sleep and wakeup function of the sensor node, it is easy to implement by controlling the state of the RF transceiver to the sleep state and the Rx state.

(B) In case of the preamble packet recognition function of the receiving node, it is possible to detect a preamble packet of a transmitting node by detecting a channel of a certain period through a CCA (Clear Channel Assessment).

If the channel is idle at the wakeup time of the receiving node, it is determined that the transmitting node has not transmitted the preamble packet and the next duty cycle is performed. If the channel is busy, the transmitting node determines that the preamble packet has been transmitted. .

(C) The function of recognizing the Early ACK packet of the transmitting node can be implemented through the CCA similar to the preamble packet recognition function of the receiving node. After the transmitting node transmits one preamble packet, the early ACK interval starts and the channel is detected.

If the channel is idle, it determines that the destination node has not transmitted the Early ACK packet, stops the Early ACK interval, and immediately transmits the next preamble packet.

On the other hand, if the channel is busy, it is determined that the destination node has transmitted the Early ACK packet, and it waits to receive it.

Finally, (D) Timing control functions of each of these functions can be implemented by using the timer provided by the MCU. Since the CCA time for the early termination of the transmitting node and the idle listening time of the receiving node are fixedly set to 2 ms and 5 ms, respectively, irrespective of the data transmission rate in the XY-MAC, the present invention can be implemented without modification.

On the other hand, since B-MAC + does not use the early ACK interval of the transmitting node, it is necessary to maintain the idle listening only during the CCA time in order to recognize the preamble packet at the wakeup time of the receiving node. Therefore, it can be implemented by applying 2ms, which is the same as CCA time in XY-MAC. In case of the sleep interval, it can be applied flexibly according to the requirements of the user or the characteristics of the application.

The operation of the hybrid MAC protocol of the data collection application device in the wireless sensor network according to the present invention will be described in detail.

The hybrid MAC protocol is divided into B-MAC + Phase and XY-MAC Phase. Each node repeatedly performs B-MAC + Phase and XY-MAC Phase until its lifetime expires.

Analyzing a data packet received through a transceiver and a receiver of a physical layer; Operating as B-MAC + in the broadcasting type traffic in the downlink direction in the data collection tree, and in XY-MAC in the convergecasting type traffic in the uplink direction; And performing packet generation by control of the hybrid MAC operation control module.

First, the operation process of the hybrid MAC protocol of the collecting node is as follows.

S101 to S107 in FIG. 10A show the operation process of the collecting node.

The B-MAC + Phase operation of the collecting node sends the B-MAC + based preamble packet and the collection request data to the lower node to propagate the data collection request.

And the XY-MAC Phase operation of the acquisition node waits for a data collection response from all the lower nodes.

When recognizing the preamble packet, it determines whether it is the destination node through the address of the destination node included in the preamble packet. If it is the destination node, it sends the Early ACK packet to the transmitting node to receive the actual data.

The operation procedure of the hybrid MAC protocol of the sensor node is as follows.

S111 to S133 of FIG. 10B show the operation process of the sensor node.

In the B-MAC + Phase operation of the sensor node, the normal node and the leaf node wait for the same data collection request.

At this time, minimum idle listening according to B-MAC + is performed and the duty cycle is performed. When recognizing the preamble packet at the idle listening time, it determines whether the preamble packet is the destination node through the address of the destination node included in the preamble packet.

Also, the mobile station maintains the sleep state for a short period of time through the preamble packet number included in the preamble packet, and then wakes up again to receive the actual data.

Then, if it is not a leaf node, it transmits the B-MAC + based preamble packet and the collection request data to the lower node to propagate the data collection request.

The XY-MAC Phase operation of the sensor node is as follows.

If it is a leaf node, its sub-node does not exist, so it directly sends an XY-MAC based preamble packet and collection response data to its parent node.

A normal node that is not a leaf node performs a duty cycle according to the XY-MAC to wait for a data collection response from its child nodes.

When recognizing the preamble packet at the idle listening time, it determines whether the preamble packet is the destination node through the address of the destination node included in the preamble packet. At this time, if the node is the destination node, it transmits the Early ACK packet to the transmitting node to receive the actual data.

Then, it collects the collection response data of itself and the lower node, and transmits the XY-MAC based preamble packet and the collection response data to transfer the data collection response to the upper node.

The present invention can be applied to all data collection applications of a wireless sensor network.

In spite of the spanning tree as a collection node as a connection method between sensor nodes for data collection, various topologies such as star and linear multi-hop can be used in a real environment depending on the environment in which the sensor node is installed.

However, since the present invention is designed by analyzing the transmission pattern of the data collection application, the present invention can be applied as long as the data communication is performed by the information request of the collection node and the response of the sensor node according to the data communication, regardless of the topology.

The apparatus and method for collecting data in a wireless sensor network according to the present invention are characterized in that in the data collection tree, in a broadcasting type traffic in the downlink direction, the apparatus operates as B-MAC + In convergecasting traffic, it works as XY-MAC to increase energy efficiency while reducing data collection time.

As described above, it will be understood that the present invention is implemented in a modified form without departing from the essential characteristics of the present invention.

It is therefore to be understood that the specified embodiments are to be considered in an illustrative rather than a restrictive sense and that the scope of the invention is indicated by the appended claims rather than by the foregoing description and that all such differences falling within the scope of equivalents thereof are intended to be embraced therein It should be interpreted.

91. Transceiver 92. Receiver
93. Packet interpreter 94a. Traffic Analyzer
94b Node Analyzer 94c. MAC protocol analyzer
95. Packet generator 96. Transmitter

Claims (12)

A data collection application in a wireless sensor network,
A packet analyzer for analyzing a data packet received through a transceiver and a receiver of a physical layer;
A hybrid MAC operation control module for performing traffic analysis and node analysis of packets analyzed by the packet analyzer and analyzing a MAC protocol to apply preamble sampling techniques of different protocols to downlink traffic and uplink traffic in a data collection tree;
And a packet generator for performing packet generation under the control of the hybrid MAC operation control module is configured in a MAC layer. The method of claim 1, wherein the hybrid MAC operation control module comprises:
A traffic analyzer for analyzing a traffic characteristic of the analyzed packet,
A node analyzer for receiving node information from a network layer and performing node analysis,
B-MAC + in the broadcasting type traffic in the downlink direction from the data collection tree by performing the MAC protocol analysis, and in the convergecasting type traffic in the uplink direction, the XY- And a MAC protocol analyzer for allowing the MAC protocol analyzer to operate as a MAC. The method as claimed in claim 1, wherein the function performed by the hybrid MAC operation control module comprises:
A sleeping and wake-up function of a sensor node, a preamble packet recognition function of a receiving node, an Early ACK packet recognition function of a transmitting node, and a timing control function of each of these functions. Application device. 4. The method of claim 3, wherein the sleep and wake-
And the RF transceiver is controlled to be in a sleep state and an Rx state. 4. The method of claim 3, wherein the preamble packet recognition function of the receiving node comprises:
A preamble packet of a transmitting node is detected by detecting a channel of a predetermined interval through a CCA (Clear Channel Assessment)
If the channel is idle at the wake-up time of the receiving node, it is determined that the transmitting node has not transmitted the preamble packet, the next duty cycle is performed,
If the channel is busy, it determines that the transmitting node has transmitted the preamble packet and waits to receive the preamble packet. The method of claim 3, wherein the function of recognizing the Early ACK packet of the transmitting node comprises:
After the transmitting node transmits one preamble packet, it detects the channel at the same time that the Early ACK interval starts,
If the channel is idle, it determines that the destination node has not transmitted the Early ACK packet, stops the Early ACK interval, immediately transmits the next preamble packet,
If the channel is busy, it determines that the destination node has transmitted the Early ACK packet and waits to receive it. The apparatus of claim 3, wherein the timing control function comprises:
The CCA time for early termination of the transmitting node and the idle listening time of the receiving node are fixedly applied at 2 ms and 5 ms, respectively, regardless of the data transmission rate in the XY-MAC,
Since the B-MAC + does not use the Early ACK interval, the B-MAC + keeps the idle listening only for the CCA time of 2ms in order to recognize the preamble packet at the wakeup time of the receiving node,
Wherein the sleep interval is differently applied according to a user's requirement or a characteristic of an application to be applied. The operation of the hybrid MAC protocol of a data acquisition application device in a wireless sensor network,
Analyzing a data packet received through a transceiver and a receiver of a physical layer;
Operating as B-MAC + in the broadcasting type traffic in the downlink direction in the data collection tree, and in XY-MAC in the convergecasting type traffic in the uplink direction;
And performing packet generation by control of the hybrid MAC operation control module. 9. The method of claim 8, wherein the B-MAC + Phase operation of the collecting node comprises transmitting a preamble packet and collection request data based on the B-MAC + to the lower node to propagate the data collection request. Methods of data collection in a network. 9. The method of claim 8, wherein the XY-MAC Phase operation of the collecting node comprises waiting a data collection response from all the lower nodes,
When recognizing a preamble packet, determining whether the node is a destination node through an address of a destination node included in a preamble packet, and if the node is a destination node, transmitting an Early ACK packet to a transmitting node to receive actual data A method of data collection in a wireless sensor network. 9. The method of claim 8, wherein the B-MAC + Phase operation of the sensor node comprises:
The normal node and the leaf node wait for a data collection request in the same manner, perform a minimum idle listening according to B-MAC + and perform a duty cycle,
Determining whether the preamble packet is a destination node through an address of a destination node included in a preamble packet when recognizing a preamble packet at an idle listening time;
The method comprising the steps of: maintaining a sleep state for a predetermined period of time through a preamble packet number included in a preamble packet,
And transmitting the preamble packet and the collection request data based on the B-MAC + to the lower node to propagate the data collection request if the node is not a leaf node. The method of claim 8, wherein the XY-MAC Phase operation of the sensor node comprises:
If the node is a leaf node, transmitting the preamble packet and the collection response data based on the XY-MAC to the upper node immediately;
a general node other than the leaf node performs a duty cycle according to the XY-MAC to wait for a data collection response from its lower node,
When recognizing a preamble packet at an idle listening time, determining whether the node is a destination node through an address of a destination node included in a preamble packet and transmitting an Early ACK packet to a transmitting node if the node is a destination node,
And collecting the collection response data of the node and the lower node and transmitting the XY-MAC based preamble packet and the collection response data to transmit the collection response data to the upper node. Data collection application method.

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