KR101539188B1 - Packet transferring method in multi hop node using ambient backscatter communication and m2m communication system using adhock network based on ambient backscatter communication - Google Patents

Abstract

A packet transmission method in a multi-hop node using ambient backscatter communication comprises: a step where a first node for performing ambient backscatter communication transmits packets; and a step where the ambient backscatter communication is carried out and a second node that is one hop away from the first node receives the packet and transmits the received packets to a peripheral node in accordance with time synchronization in order for constructive interference to occur in a received signal.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for transmitting a packet in a multi-hop node based on an ambient backscatter communication and an object communication system including an ad hoc network based on an ambient backscatter communication. ON AMBIENT BACKSCATTER COMMUNICATION}

The technique described below relates to a technique for transmitting packets in an ambient backscatter communication based network.

Ambient Backscatter is a zero-power communication technique developed by University of Washington researchers in 2013. The surrounding radio signals (eg, TV, mobile communication, WiFI, etc.) can be collected as usual energy, and if necessary, signals can be absorbed or reflected to communicate between two adjacent devices. Such a communication environment can continuously absorb relatively weak peripheral radio signals and store them as energy and transmit / receive information with very low power consumption.

There is a passive RFID as a representative technology of the conventional backscatter. An RFID reader transmits a command through a radio signal to an adjacent RFID tag, and then transmits a radio signal of a fixed strength to receive information from the RFID tag. The RFID tag uses the received energy to backscatter the wireless signal transmitted from the RFID reader to its ID information. There are various application services using RFID and it is growing steadily.

Korean Patent Publication No. 10-2008-0052367

Acknowledgments The ACM SIGCOMM 2013 conference on SIGCOMM, pp. 39-50, pp. 39-50, p. Published paper Aaron N. Parks, Angli Liu, Shyamnath Gollakota, Joshua R. Smith, "Turbocharging Ambient Backscatter Communication", SIGCOMM'14, August 17-22 page 2014 Internet web page http://abc.cs.washington.edu/

The RFID system is limited in that all the RFID tags can transmit information only to the RFID readers, and the RFID tags and the RFID readers must be located within a communicable distance. On the other hand, the Ambient Backscatter communication of the University of Washington allows any two devices to send and receive information using the surrounding radio signals. However, if the two devices are out of the communication range, communication is impossible.

The following description is based on an ambient backscatter communication technique, and a multi-hop network is constructed, and a packet transmission method is proposed in a multi-hop network or an ad hoc network.

The solutions to the technical problems described below are not limited to those mentioned above, and other solutions not mentioned can be clearly understood by those skilled in the art from the following description.

A method for transmitting a packet in a multi-hop node based on an ambient backscatter communication includes a first node performing an ambient backscatter communication and an ambient backscatter communication, Receiving the packet and transmitting the received packet to the neighboring node in time synchronization so that constructive interference occurs in the received signal.

The second node may repeatedly transmit the received packet in time synchronization so that constructive interference occurs in the received signal.

The second node can transmit the received packet to the neighboring node when the hop distance from the reference node, which is a distance reference, is smaller than or equal to the first node.

An object communication system including an ad hoc network for performing ambient backscatter communication includes a sensor device for collecting information and transmitting a packet including the information, an ambient backscatter communication device for performing ambient backscatter communication with the sensor device at a one- A first relay node for receiving the packet and transmitting the received packet in time synchronization so as to cause constructive interference with the received signal; a second relay node for receiving the packet while performing ambient backscatter communication with the first relay node at a one- A second relay node for transmitting the received packet in time synchronization so that constructive interference occurs in the received signal, and a destination node for receiving the packet via the second relay node.

The sensor device receives an external wireless signal, not the wireless signal used in the object communication system, and uses the energy contained in the external wireless signal as electric power.

At least one of the first relay node and the second relay node may repeatedly transmit the received packet in time synchronization so that constructive interference occurs in the received signal.

Wherein at least one of the first relay node and the second relay node is a plurality of relay nodes, the plurality of relay nodes repeatedly transmit the received packet in time synchronization so that constructive interference occurs in the received signal, Wherein at least one of the nodes included in the node includes at least one of a number of relay nodes, a repetition number of transmissions, a power required for transmission of each node belonging to the plurality of relay nodes, a remaining power of each node belonging to the plurality of relay nodes, The packets may be transmitted in a different order from the remaining nodes included in the plurality of relay nodes in consideration of at least one of the power charging rates of the respective nodes belonging to the relay node.

The technique described below is based on the ambient backscatter communication technique, which allows a packet to be forwarded to a node at a distance without using additional power. Using the techniques described below, it is possible to construct a network that does not consume energy in object communication, sensor networks, and the like.

The effects of the techniques described below are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is an example of a communication system including an ambient backscatter communication based node.
2 is an example of an operation of transmitting a packet in the communication system of Fig.
3 is another example of an operation for transmitting a packet in the communication system of Fig.
4 is an example of an operation for repeatedly transmitting a packet in the communication system of Fig.
FIG. 5 shows an example of an object communication system based on ambient backscatter communication.
FIG. 6 shows an example in which packets are transmitted in a communication system based on ambient backscatter communication.

The following description is intended to illustrate and describe specific embodiments in the drawings, since various changes may be made and the embodiments may have various embodiments. However, it should be understood that the following description does not limit the specific embodiments, but includes all changes, equivalents, and alternatives falling within the spirit and scope of the following description.

The terms first, second, A, B, etc., may be used to describe various components, but the components are not limited by the terms, but may be used to distinguish one component from another . For example, without departing from the scope of the following description, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

As used herein, the singular " include "should be understood to include a plurality of representations unless the context clearly dictates otherwise, and the terms" comprises & , Parts or combinations thereof, and does not preclude the presence or addition of one or more other features, integers, steps, components, components, or combinations thereof.

Before describing the drawings in detail, it is to be clarified that the division of constituent parts in this specification is merely a division by main functions of each constituent part. That is, two or more constituent parts to be described below may be combined into one constituent part, or one constituent part may be divided into two or more functions according to functions that are more subdivided. In addition, each of the constituent units described below may additionally perform some or all of the functions of other constituent units in addition to the main functions of the constituent units themselves, and that some of the main functions, And may be carried out in a dedicated manner. Accordingly, the existence of each component described in the present specification should be interpreted as a function. For this reason, the communication system 100 including the multi-hop node based on the ambient backscatter communication of the technology described below and the ambient backscatter It is clear that the configuration of the components according to the object communication system 300 including the communication-based ad hoc network can be different from the corresponding figure within the scope of achieving the object of the following description.

Also, in performing a method or an operation method, each of the processes constituting the method may take place differently from the stated order unless clearly specified in the context. That is, each process may occur in the same order as described, may be performed substantially concurrently, or may be performed in the opposite order.

Hereinafter, the object communication system 300 including the communication system 100 including the multi-hop node based on the ambient backscatter communication and the ad hoc network based on the ambient backscatter communication will be described in detail with reference to the drawings.

As described above, the technique described below is based on a backscatter communication technique disclosed by the University of Washington. 1 is an illustration of a communication system 100 including an ambient backscatter communication based node. In the lower part of FIG. 1, several nodes transmit specific data packets through backscatter technology.

1, the node 1 transmitting the initial data is represented by S in the sense of a source node, and the node 10 finally receiving data is represented by T in the sense of a target node. And the other nodes 5, 6 and 7 denote R as a relay node.

The nodes in Fig. 1 have different code numbers or symbols, but they can be hardware identical nodes. Alternatively, the node 1 for collecting data and the nodes 5, 6 and 7 for relaying data may have different configurations. The node 10, which is finally receiving data, may be a device such as a relay node, a gateway device or an AP for transmitting data to another network, or may be a server device or a database device It is possible.

The node in Figure 1 is a network device without its own power supply (battery). At least the nodes (1, 5, 6 and 7) involved in data transfer correspond to devices using the ambient backscatter communication technique. In some cases, the node 10 that has finally collected the data in FIG. 1 may also be an apparatus using an ambient backscatter communication technique.

A node using an ambient backscatter communication method collects radio signals received by a node, stores energy (power), and transmits / receives data using stored energy. In FIG. 1, a signal transmitted from a TV repeater, a signal transmitted from a mobile communication base station, a signal transmitted by an adjacent Wi-Fi AP, and a wireless power transmission (WPT) signal are shown as examples of radio signals. The backscatter communication technique is characterized by using a radio signal that can be heard around the current node as an energy source. Thus, the node of Figure 1 needs a module for storing the radio signal as an energy source. A detailed description of the principle of the ambient backscatter communication will be omitted.

On the other hand, when the node 6 transmits a packet in an ambient backscatter manner, the node 7 receiving the signal transmitted by the node 6 may use the signal itself transmitted from the node 6 as an energy source. That is, in the communication system 100, a node may use a signal transmitted by another node as an energy source.

It is assumed that the data transmitted by the node is a packet having a specific standard. Hereinafter, it is proposed to transmit a packet in a multi-hop system where a plurality of ambient backscatter communication nodes are present.

Fig. 2 is an example of an operation for transmitting a packet in the communication system 100 of Fig. An ambient backscatter communication based node forwards packets to other nodes in an ambient backscatter manner. Hereinafter, the expression " transmitting / transmitting a packet " is based on an ambient backscatter system. Since the packet is transmitted using limited energy, the distance over which the packet is transmitted may be limited. Meanwhile, the signal transmitted by the node corresponds to an analog signal having a specific waveform.

It is necessary to efficiently determine when and from among a plurality of nodes that have received the signal including the packet. The CSMA / CA scheme is a typical distributed radio channel access technology, but collision can occur due to individual transmission attempt and control overhead is required to avoid collision due to a hidden node problem (inherent problem of radio channel). In the communication system 100, a plurality of nodes transmit signals correctly at the same time, so that neighboring nodes can correctly receive signals using a constructive interference effect instead of a collision.

FIG. 2 shows an example in which a packet received by each node is transmitted only once. In FIG. 2, a dotted circle shows an area where one node can transmit a packet in a backscatter manner.

Referring to FIG. 2 (a), node 1 transmits a packet in a time slot '0'. Packets transmitted by node 1 are forwarded to node 2 and node 3. Referring to FIG. 2B, node 2 and node 3 simultaneously transmit the received packets to time slot '1'. The packet transmitted by node 2 is delivered to node 1, node 3 and node 5, and the packet transmitted by node 3 is delivered to node 1, node 2 and node 4. Referring to FIG. 2 (c), the node 4 and the node 5 transmit the received packet to the time slot '2'. The packet transmitted by the node 4 is transmitted to the node 3 and the node 5, and the packet transmitted by the node 5 is transmitted to the node 2 and the node 4. As a result, packets are transmitted to all the nodes by transmitting the packets to the nodes in one hop distance in an ambient backscatter manner.

FIG. 3 is another example of an operation for transmitting a packet in the communication system 100 of FIG. FIG. 3 shows an example in which each node repeatedly transmits a received packet twice to increase reliability.

Referring to FIG. 3 (a), the node 1 transmits a packet in a time slot '0'. Packets transmitted by node 1 are forwarded to node 2 and node 3. However, it is assumed that node 3 did not receive the packet at this time. The node 3 may not be able to receive packets normally due to insufficient energy or interference.

Referring to FIG. 3B, a node 2 transmits a packet to a time slot '1', and a packet transmitted by the node 2 is transmitted to a node 1, a node 3, and a node 5.

Referring to FIG. 3 (c), nodes 1, 3, and 5 simultaneously transmit packets in a time slot '2'. Node 1 is repeating the second transmission. Repeated transmissions are shown in bold solid lines in FIG. The packet transmitted by node 3 is delivered to node 1, node 2 and node 4, and the packet transmitted by node 5 is delivered to node 2 and node 4.

Referring to FIG. 3 (d), the node 2 performs the second transmission in the time slot '3', and the node 4 simultaneously transmits the packet. The packet transmitted by node 4 is delivered to node 3 and node 5.

Referring to FIG. 3 (e), node 3 and node 5 repeat the second transmission in time slot '4'. Referring to FIG. 3 (f), node 4 is transmitting a second time slot '5'.

As shown in FIG. 3, if each node repeats transmission, even if a situation occurs in which a neighbor node can not receive a packet, there is a high possibility that a packet is delivered to all nodes. The number of iterations can be set according to the performance of the node, the distance between the nodes, the residual energy of the node, and so on.

FIG. 4 is an example of an operation for repeatedly transmitting a packet in the communication system 100 of FIG.

Fig. 4 (a) shows another example of the communication system 100 of Fig. And four nodes for initially receiving a signal from the node S (1). That is, this is the case where there are a plurality of nodes (R1-1, R1-2, R1-3, and R1-4) one-hop distance from the node S (1).

In the communication system 100, there may be a plurality of nodes having a distance of one hop from a specific node. As shown in Fig. 4 (a), there may be a plurality of nodes 5 that are one-hop distance from the node S (1). There may be a plurality of nodes 6 one-hop distance from the node 5 or a plurality of nodes 7 one-hop distance from the node 6. [ For convenience of explanation, as an example, a case where a plurality of nodes 5 that are one-hop distance from the node S (1) as shown in FIG.

Referring to FIG. 4 (a), four nodes at a distance of one hop from the node S (1) are R1-1, R1-2, R1-3, and R1-4. For convenience of explanation, four nodes at a distance of one hop from the node S (1) are referred to as a first level node. The node 5 is a first level node, the node 6 is a second level node, and the node 7 is a third level node depending on the distance from the node transmitting the original packet.

As shown in FIG. 4 (a), when there are a plurality of first level nodes, a node belonging to the first level node can cooperatively perform a process of repeatedly transmitting signals. For example, the first level nodes may be divided into several groups according to the number. It is assumed that the first group includes the node R1-1 and the node R1-2, and the second group includes the node R1-3 and the node R1-4. 4B illustrates an example in which signals are transmitted while the first group node and the second group node alternate in order. In Fig. 4 (b), the abscissa indicates the order of transmission. 4 (b) shows a case where the first group (node R1-1 and node R1-2) and the second group (node R1-3 and node R1-4) It is an example of transmitting a signal with alternating order.

If a node belonging to the same level cooperatively transmits a signal, the power consumption of each node can be reduced. However, since each node collects the surrounding radio signals and stores the power, they can have different power depending on the strength of the received signal, the collection rate of power, the power consumed in signal transmission, the type and number of signals to be transmitted, have.

Therefore, at least one of the nodes belonging to the same level belongs to the same level, the number of repetition of transmission, the power required for transmission of each node belonging to the same level, the remaining power of each node belonging to the same level, The transmission can be performed considering at least one of the power charging rates of the respective nodes. This approach can be more efficient in terms of energy consumption.

FIG. 4 (c) illustrates an example in which nodes belonging to the first level repeat transmission in consideration of the above criteria. The first R1-1 and R1-3 perform the first iteration, R1-4 performs the first iteration, R1-1 performs the third iteration, and R1-3 and R1-4 perform the fourth iteration And finally, R1-2 performs the fifth iteration transmission.

In order for the nodes belonging to the first level to repeatedly perform transmission continuously in the time slot, it is preferable that each node share a reference variable such as a charging rate, a residual power, a power consumed in transmission, and the like of each node. Also, one of the nodes belonging to the first level may serve as a control node.

However, transfer iteration does not necessarily have to be done continuously. Therefore, each node may transmit a signal separately at a time when it is possible to transmit it considering its own residual power, power consumed in transmission, charge rate, and the like.

FIG. 5 shows an example of an object communication system 300 based on ambient backscatter communication. Fig. 5 corresponds to an example in which the communication system 100 of Fig. 1 is applied to object communication. In Fig. 5, the source node is a sensor device for sensing information, the relay node is a device for relaying information, and the destination node is a device for collecting information.

In FIG. 5, a sensor device for sensing certain information is indicated by M (311, 312 and 313), a device for relaying the sensed information is indicated by R (321 to 326), and finally a device for collecting information ). The apparatus 350 for collecting information corresponds to a server that processes or stores the collected information. Further, the apparatus 350 for collecting information may be a gateway apparatus or an AP apparatus for transferring collected information to another network.

On the other hand, the relay apparatus R (312 to 326) may be a device that performs only a function of relaying information, or may collect information as a sensor device. In the latter case, the sensor device M and the relay device R may be devices having the same hardware. In this case, the object communication system 300 will correspond to an Ad-Hoc network using a sensor device.

One or more devices 350 for collecting final information may exist and their locations may also be known or unknown in advance. When the sensor device M transmits information collected by itself, the relay device, which is a node at a one-hop distance, can receive it. The relay apparatus receiving the signal transmitted by the sensor apparatus transmits the received signal so that constructive interference occurs as described in FIG.

The object communication system 300 can be largely divided into three types according to a signal transmission method. The first is always flooding to all nodes, so intermediate nodes deliver according to their power situation. In the second case, only the initial signal is flooded to the entire network, and if the destination node sends a response signal, only the intermediate nodes in the reverse direction participate in signal transmission. Third, the destination node periodically sends a signal and the signal is flooded to the entire network, and the intermediate nodes memorize the routing information of the destination (such as distance information to the destination). When the intermediate node receives a signal directed to a specific destination, it determines whether to deliver it according to preset routing information.

Returning to the description of FIG. 5, the sensor device M1 311 transmits a signal including the sensed information, and transmits the signal received by the relay device R1 321, which is one-hop distance from the M1 311, again. At this time, the Rl 321 may repeatedly transmit a signal so that the received signal may be constructively interfered. The signal transmitted by R1 321 (the signal interfered with the signal of M1) is transmitted to R3 323 and R4 324 which are one hop away from R1 321. At this time, the R323 and the R324 may repeat the transmission cooperatively as illustrated in FIG. The signal transmitted by R3 323 and / or R4 324 is transmitted to collector device 350 via R6 326. The information sensed by the other sensor apparatuses M2 (312) and M3 (313) is also transmitted to the collecting apparatus 350 in a similar manner.

Referring to FIG. 5, each relay device can receive signals transmitted from different sensor devices. For example, R4 324 is a relay device that is two hops away from M1 311 and M2 312, and a relay device that is one hop away from M3 313. The R4 324 may receive and transmit a signal sensed by all of the sensor devices 311, 312, and 313 shown in FIG. However, in this case, the R4 324 may exhaust power collected by frequent transmission.

Therefore, nodes that perform repetitive transmission must manage their own power efficiently. (1) For example, the R4 324 may perform transmission once for a new signal without performing a process of repeatedly transmitting. (2) Furthermore, if the path from the initial sensor device to the collecting device is determined in the object communication system 300, and each path is managed in the R4 324 in the form of a routing table, the R4 324 does not necessarily transmit You may know the signal you do not need. For example, a signal transmitted from M1 311 or a signal transmitted from M3 313 exists in an alternative path. In this case, the R4 324 may be set to transmit only the signal transmitted from the M2 312.

6 is an example in which a packet is transmitted in the communication system 400 based on the ambient backscatter communication.

In FIG. 6, M1 411 and M2 412 are information sensing devices for sensing specific information such as sensors, Rs 421 through 427 correspond to relay nodes relaying packets, and C 450 finally It corresponds to an information collecting device that collects information. In FIG. 6, each node transmits data in a manner of transmitting a packet according to the method described with reference to FIG. 2 to FIG.

In FIG. 6A, the information collecting apparatus C 450 transmits packets to the entire network while transmitting certain packets. Through this process, each node can grasp the hops distance from the information collecting device C (450). For example, R6 426 and / or R7 427 are one hop away from information collection device C 450. R3 423 and R4 424 are one hop away from R6 426 and R7 427 and are two hops away from information collecting device C 450.

Meanwhile, when the node R6 426, which is one hop away from each other, transmits a packet received from the information collecting apparatus C 450 to the R7 427, the R7 427 transmits the packet to the information collecting apparatus C 450, It is presumed that the hop distance is not increased when receiving the already received packet in order to exclude this case. Therefore, it is determined that R6 426 and R7 427 have a one-hop distance from the information collecting device C 450, respectively.

In this manner, the information collecting apparatus C 450 can transmit an arbitrary packet to grasp the hop distance to each node of the entire network. 6 is the hop distance from the information collecting apparatus C (450). Each node stores the hop distance from the information collection device C (450) in the routing table.

Each node can then determine whether to retransmit the received packet using the stored hop distance. 6 (b). In FIG. 6 (b), each node transmits a packet when the hop distance of a node that has transmitted a currently received packet (called a previous node) is greater than or equal to its own hop distance. That is, only the node having the same or smaller distance from the information collecting device C (450) than the previous node transmits the packet. This is to prevent packets from being transmitted in the opposite direction, not in the direction of information transfer, and at the same time to reduce unnecessary energy consumption.

The information sensing device M2 412 transmits the information sensed by the information sensing device M2 412 in a packet form. The packet transmitted by the information sensing device M2 412 is received by the relay node R2 422 which is one hop away. The relay node R2 422 transmits the received packet because the hop distance of the information sensing apparatus M2 412 as the previous node is 4 and its own hop distance is 3.

And the packets transmitted by the relay node R2 422 are transmitted to the relay node R4 424 and the relay node R5 425, respectively.

The relay node R4 424 and the relay node R5 425 each transmit the received packet. The hop distance of the relay node R2 422 is smaller than the hop distance of the relay node R2 422 which is the previous node.

Meanwhile, the relay node R4 424 and the relay node R5 425 can receive packets transmitted from each other. The relay node R5 425 no longer transmits the node transmitted by the relay node R4 424 if the hop distance of the previous node is set to a value larger than the hop distance of the previous node. If the hopping distance of the previous node is set to be equal to or greater than its own reference, the relay node R5 425 will transmit the packet transmitted by the relay node R4 424 again. In FIG. 6 (b), it is assumed that the hopping distance of the previous node is set to a case where the hopping distance of the previous node is equal to or greater than itself.

The packet transmitted by the relay node R4 424 and the relay node R5 425 is transmitted to the relay node R7 427 and the packet transmitted by the relay node R7 427 is transmitted to the relay node R6 426 and the information collecting node C (450). Meanwhile, the relay node R6 426 may forward the packet received from the relay node R7 427 to the information collection node C 450. [

It should be noted that the present embodiment and the drawings attached hereto are only a part of the technical idea included in the above-described technology, and those skilled in the art will readily understand the technical ideas included in the above- It is to be understood that both variations and specific embodiments which can be deduced are included in the scope of the above-mentioned technical scope.

100: communication system including nodes based on ambient backscatter communication
1, 5, 6, 7, 10: Node
1: source node 5, 6, 7: relay node
10: destination node
300: Ambient backscatter communication based object communication system
311, 312, 313: sensor device
321, 322, 323, 324, 325, 326:
350: Collecting device
400: Ambient Backscatter Communication Based Communication System
411, 412: Information sensing device
421, 422, 423, 424, 425, 426, 427:
450: Information collecting device

Claims (16)

Transmitting a first signal including a packet by a first node performing ambient backscatter communication;
Performing ambient backscatter communication and receiving a first signal from a second node that is one hop away from the first node; And
And transmitting a second signal including the packet to the neighboring node in time synchronization so that the second node is undergoing constructive interference with the first signal transmitted through the second node, Hop node in a multi-hop node. The method according to claim 1,
Wherein the first node and the second node receive the separate wireless signal and use the energy contained in the wireless signal as the power, in the multi-hop node based on the ambient backscatter communication. The method according to claim 1,
Wherein the first node and the second node receive the signal including the packet and use the energy contained in the signal as the power, in the multi-hop node based on the ambient backscatter communication. The method according to claim 1,
Wherein the second node repeatedly transmits the second signal in synchronization with time synchronization so as to cause constructive interference with the first signal. 5. The method of claim 4,
When a plurality of the second nodes are one-hop distance from the first node, the plurality of second nodes are divided into a first group and a second group,
Hop node that repeatedly transmits the second signal in a different order from a node belonging to the first group to a node belonging to the second group in the course of repeating the transmission, Way. The method according to claim 1,
The second node repeatedly transmits the second signal received in time synchronization with the first signal so as to cause constructive interference with the first signal, ,
Wherein at least one of the nodes included in the plurality of second nodes includes at least one of a number of second nodes, a repetition number of transmissions, a power required for transmission of each node belonging to the plurality of second nodes, The second node transmits the second signal in a different order than the remaining nodes included in the plurality of second nodes in consideration of at least one of the remaining power of each node and the power charging rate of each node belonging to the plurality of second nodes A method for transmitting a packet in a multi-hop node based on backscatter communication. The method according to claim 1,
The second node transmits the received second signal to the neighboring node when the hop distance from the second node to the reference node, which is a distance reference, is less than or equal to the hop distance from the first node to the reference node, A method for transmitting a packet in a multi-hop node based on an ambient backscatter communication. 8. The method of claim 7,
Wherein the reference node is a node for collecting information, wherein the reference node is an ambient backscatter communication based multi-hop node. A sensor device for collecting information and transmitting a first signal comprising a packet containing said information;
Receiving the first signal while performing ambient backscatter communication with the sensor device at a one-hop distance, synchronizing time synchronization with the first signal transmitted through the first relay node to generate constructive interference, A first relay node for transmitting a second signal;
Receiving the second signal while performing ambient backscatter communication with the first relay node at a one-hop distance, and synchronizing the second signal with the second signal transmitted through the second relay node so that constructive interference occurs, A second relay node for transmitting a third signal comprising; And
And an ad-hoc network for performing ambient backscatter communication including a destination node for receiving the third signal. 10. The method of claim 9,
Wherein the sensor device comprises an ad-hoc network based on an ambient backscatter communication that uses an energy contained in the external wireless signal as power by receiving an external wireless signal other than the wireless signal used in the object communication system. 10. The method of claim 9,
Wherein at least one of the first relay node and the second relay node receives a separate external radio signal and uses energy contained in the external radio signal as electric power, the object communication system including an ad hoc network based on an ambient backscatter communication . 10. The method of claim 9,
At least one of the first relay node and the second relay node includes an ad hoc network based on an ambient backscatter communication that receives a signal transmitted from the sensor device or another relay node and uses the energy contained in the signal as electric power Communication system. 10. The method of claim 9,
Wherein at least one of the first relay node or the second relay node repeatedly transmits a signal including the packet, wherein the at least one of the first relay node and the second relay node comprises an ad hoc network based on an ambient backscatter communication. 14. The method of claim 13,
Wherein the first relay node is divided into a first group and a second group when the first relay node is one-hop distance from the sensor device,
An ad hoc network based on an ambient backscatter communication in which nodes belonging to the first group and nodes belonging to the second group transmit the second signal in different orders. 14. The method of claim 13,
When a plurality of the second relay nodes are one-hop distance from the first relay node, the plurality of second relay nodes are divided into a first group and a second group,
An ad hoc network based on an ambient backscatter communication in which nodes belonging to the first group and nodes belonging to the second group transmit the third signal in different orders. 10. The method of claim 9,
Wherein at least one of the first relay node and the second relay node is a plurality of relay nodes, the relay node repeatedly transmits a signal including the packet,
Wherein at least one of the nodes included in the plurality of relay nodes includes at least one of a number of relay nodes, a repetition number of transmissions, a power required for transmission of each node belonging to the plurality of relay nodes, An ad hoc network based on an ambient backscatter communication that transmits the signals in a different order than the remaining nodes included in the plurality of relay nodes in consideration of at least one of a power and a power charging rate of each node belonging to the plurality of relay nodes Object communication system.

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