KR20180090179A - Method and apparatus for routing in multihop network - Google Patents

Abstract

A routing method performed in a multi-hop network is disclosed. The routing method comprises: a step of allowing at least one relay node included in a first path to relay communication between a source node and an end node; a step of reporting a channel quality degradation to the source node when the first relay node included in the first path detects the quality degradation of a channel for a destination node specified in the first relay node; and a step of allowing the first relay node to extend the first path by adding a second relay node between the first relay node and the destination node. It is possible to change a communication path efficiently.

Description

[0001] METHOD AND APPARATUS FOR ROUTING IN MULTIHOP NETWORK [0002]

The present invention relates to a routing method performed in a multi-hop network, and more particularly, to a technique for efficiently changing a communication path when a failure occurs in a wireless channel between communication nodes included in a multi-hop network.

The communication system may be a core network (e.g., a mobility management entity (MME), a serving gateway (SGW), a packet data network (PDW) A small base station, a relay, etc.), a terminal, and the like. Communication between a base station and a terminal may be performed using various radio access technologies (e.g., 4G communication technology, 5G communication technology, WiBro (wireless broadband) technology, wireless local area network (WLAN) Etc.). ≪ / RTI >

Recently, research on communication technology using millimeter wave (mmWave) band is actively conducted in wireless communication. The millimeter wave band has many advantages over multiple communications over the microwave band. However, the millimeter wave band has a higher channel attenuation and noise power than the microwave band. In order to solve the above-mentioned problem, the problem of channel attenuation can be solved to some extent by making the propagation of the millimeter wave band have directivity and straightness. However, in this case, if an obstacle exists in the propagation path, the influence of the signal attenuation caused by the obstacle may be large due to the directivity of the radio wave.

In order to maintain communication performance in a mobile environment, there is a demand for a routing technology capable of efficiently changing a communication path in accordance with a channel state change between communication nodes.

The present invention provides a method for efficiently changing a communication path by appropriately combining a path extending method and a path re-setting method when a failure occurs in a wireless channel between communication nodes included in a multi-hop network.

According to an aspect of the present invention, there is provided a routing method performed in a multi-hop network, the method comprising: relaying communication between a source node and an end node by at least one relay node included in a first path; Reporting the channel quality degradation to the source node when a first relay node included in the first path detects a channel quality degradation for a destination node designated in the first relay node; The first relay node extending the first path by adding a second relay node between the first relay node and the destination node; The source node searching for a reset path for the end node; And changing, by the source node, the communication path with the end node to the detected reset path if the channel quality is not restored until the reference time elapses after the channel quality deteriorates.

The second relay node may be a communication node not included in the first path before expansion of the first path.

The first relay node may measure the channel quality between the first relay node and the destination node based on the reference signal received from the destination node.

The first relay node may determine that the channel quality is degraded when the strength of the reference signal received from the destination node is less than a reference strength.

When the first path is extended, the second relay node may relay the communication between the first relay node and the destination node.

The first relay node may exclude the second relay node from the first path if the channel quality is recovered before the reference time has elapsed after the channel quality degrades.

The first relay node transmits a communication relay stop request message to the second relay node when the channel quality is recovered before the reference time passes after the channel quality deteriorates, Upon receiving the interruption request message, the communication relay between the first relay node and the destination node can be stopped.

The source node may not change the communication path to the end node to the reset path if the channel quality is recovered before the reference time after the channel quality degrades.

A method of operating a source node in a multi-hop network according to an exemplary embodiment of the present invention includes: receiving a channel quality degradation report between a relay node included in a first path and a destination node of the relay node; Receiving channel state information between communication nodes included in the multi-hop network; Searching for a reset path for the end node based on the channel state information; And changing the communication path with the end node to the detected reset path if the channel quality is not restored until the reference time passes after the channel quality deteriorates.

The changing of the communication path to the retrieved reset path may transmit configuration information for the reset path to at least some of the communication nodes included in the multi-hop network.

The setting information for the reset path may include identification information of a relay node included in the reset path.

The setting information for the reset path may include information about a destination node of the relay node included in the reset path.

If the recovery report of the channel quality is received before the reference time has elapsed after the channel quality degrades, the source node may not change the communication path with the end node to the reset path.

A method of operating a first relay node included in a first path according to an exemplary embodiment of the present invention includes: communicating with a destination node of the first relay node designated in the first path, Relaying the communication; Reporting the channel quality degradation to the source node if it detects a degradation in channel quality between the first relay node and the destination node; Expanding the first path by the first relay node adding a second relay node between the destination node; And receiving setting information for the second path reset by the source node when the channel quality is not recovered until the reference time elapses after the channel quality is degraded.

The step of extending the first path may request the second relay node to relay the communication between the first relay node and the destination node.

The second relay node may be a communication node not included in the first path before expansion of the first path.

The first relay node may determine that the channel quality is degraded when the strength of the reference signal received from the destination node is less than a reference strength.

If the first relay node is not included in the second path, the first relay node may stop the communication relay between the source node and the end node.

The first relay node may exclude the second relay node from the first path if the channel quality is recovered before the reference time has elapsed after the channel quality degrades.

If the channel quality is recovered before the reference time has elapsed after the channel quality deteriorates, the first relay node may transmit a communication stop request message to the second relay node.

According to the present invention, it is possible to efficiently change the communication path in the multi-hop network by appropriately combining the path extending method and the path re-setting method. The routing method is a method in which after the channel quality deteriorates, the path is changed according to the path extending method before the reference time passes, and the path is changed according to the path resetting method after the reference time passes, can do.

1 is a block diagram illustrating a communication node according to an embodiment of the present invention.
2 is a conceptual diagram illustrating a multi-hop network according to an embodiment of the present invention.
FIG. 3 is a conceptual diagram illustrating an example in which the channel state of the multi-hop network shown in FIG. 2 is changed.
4 is a conceptual diagram showing a first embodiment in which a path is changed according to a path extending method.
5 is a conceptual diagram showing a second embodiment in which a path is changed according to a path extending method.
FIG. 6 is a conceptual diagram exemplarily showing a path change according to a path resetting method.
7 is a conceptual diagram illustrating a routing method of a multi-hop network according to a first embodiment of the present invention.
8 is a conceptual diagram illustrating a routing method of a multi-hop network according to a second embodiment of the present invention.
9 is a graph comparing the performance of the path extending method and the path re-setting method.
FIG. 10 is a graph for explaining the performance difference between the two schemes in the section (a) of FIG.
FIG. 11 is a graph for explaining the performance difference between the two schemes in the section (b) of FIG.
FIG. 12 is a graph for explaining the performance difference between the two schemes in the interval (c) of FIG.
FIG. 13 is a graph comparing average throughputs of a combination of a path extending method, a path resetting method, and both methods according to the speed of an end node.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, 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.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

Throughout the specification, the network can be, for example, a wireless Internet such as a low power wide area wireless communication (LPWAN), a Zigbee, a wireless fidelity (WiFi), a wireless broadband internet (WiBro) 2G mobile communication network such as GSM (global system for mobile communication) or CDMA (code division multiple access), 3G mobile communication network such as wideband code division multiple access (WCDMA) or CDMA2000, HSDPA a 3.5G mobile communication network such as a downlink packet access (HSUPA) or a high speed uplink packet access (HSUPA), a 4G mobile communication network such as an LTE (Long Term Evolution) network or an LTE-Advanced network, and a 5G mobile communication network.

In the specification, a source node, a relay node, and an end node are terms classified according to functions performed by a communication node. The functions performed by the communication node may vary depending on the situation. For example, one communication node may operate as a source node or a relay node depending on the situation. The source node may generate information to be transmitted to the end node. The source node may communicate with the end node via the relay node.

The relay node may be a communication node relaying communication between the source node and the end node. At least one relay node may relay communications between the source node and the end node.

1 is a block diagram illustrating a communication node 100 in accordance with an embodiment of the present invention.

Referring to FIG. 1, a communication node 100 may include at least one processor 110, a memory 120, and a network interface device 130 for communicating with a network. The server 100 may further include an input interface device 140, an output interface device 150, a storage device 160, and the like. Each component included in the communication node 100 may be connected by a bus 170 and communicate with each other.

The processor 110 may execute a program command stored in the memory 120 and / or the storage device 160. The processor 110 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the methods of the present invention are performed. The memory 120 and the storage device 160 may be composed of a volatile storage medium and / or a non-volatile storage medium. For example, the memory 120 may be comprised of read only memory (ROM) and / or random access memory (RAM).

2 is a conceptual diagram illustrating a multi-hop network according to an embodiment of the present invention.

Referring to FIG. 2, a multi-hop network may include a plurality of communication nodes. Some of the communication nodes may perform the function of a source node (SN). Some of the communication nodes may perform the function of a relay node (RN). The relay node can relay the communication between the source node and the end node (EN). An end node may be a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, an access terminal, an end-device and may include all or some of the functions of a terminal, a mobile station, a mobile terminal, a subscriber station, a mobile subscriber station, a user apparatus, an access terminal, and the like.

At least some of the relay nodes RN1, RN2, RN3, RN4 may relay communications between the source node SN and the end node EN. The source node SN may establish relay nodes involved in relaying the communication. For example, the source node SN may include a channel state between the relay nodes RN1, RN2, RN3, RN4, a channel state between the relay nodes RN1, RN2, RN3, RN4 and the source node SN, Relay nodes that relay communications between the source node SN and the end node EN may be determined based on channel conditions between the relay nodes RN1, RN2, RN3, RN4 and the end node EN.

For example, the source node SN can establish communication between the source node SN and the end node EN via the first path. The source node SN may request that the first relay node RN1 and the second relay node RN2 included in the first path relay the communication between the source node SN and the end node EN. The source node SN may assign a destination node to each of the first relay node RN1 and the second relay node RN2. The destination node is a destination node to which the relay node transmits a signal.

The source node SN sets the destination node of the first relay node RN1 to the second relay node RN2 and the destination node of the second relay node RN2 to the end node EN, . When the first relay node RN1 receives the downlink signal from the source node SN, it can transmit the downlink signal to the second relay node RN2. When the second relay node RN2 receives the downlink signal from the first relay node RN1, the second relay node RN2 can transmit the downlink signal to the end node EN. Each of the first and second relay nodes RN1 and RN2 may direct the directional direction of the radio wave toward the destination node of the downlink signal.

The source node SN sets the destination node of the second relay node RN2 as the first relay node RN1 and the destination node of the first relay node RN1 as the source node SN, . When the second relay node RN2 receives the uplink signal from the end node EN, it can transmit the uplink signal to the first relay node RN1. When the first relay node RN1 receives the uplink signal from the second relay node RN2, it can transmit the uplink signal to the source node SN. Each of the first and second relay nodes RN1 and RN2 may direct the directional direction of the radio wave toward the destination node of the uplink signal.

FIG. 3 is a conceptual diagram illustrating an example in which the channel state of the multi-hop network shown in FIG. 2 is changed.

Referring to FIG. 3, the channel quality between the end node EN and the second relay node RN2 may be degraded. The channel quality between the end node EN and the second relay node RN2 deteriorates due to an obstacle between the end node EN and the second relay node RN2 as the position of the end node EN changes. . As another example, even if the position of the end node EN does not change, the channel quality may deteriorate due to the appearance of an existing obstacle between the end node EN and the second relay node RN2.

In the millimeter-wave band, it is difficult to recover channel quality degradation caused by obstacles because the communication nodes generate radio waves with strong linearity. Therefore, the communication path may need to be changed in order to maintain the communication quality.

4 is a conceptual diagram showing a first embodiment in which a path is changed according to a path extending method.

Referring to FIG. 4, the second relay node RN2 can detect that the channel quality between the second relay node RN2 and the end node EN is degraded. The second relay node RN2 can exchange reference signals with the end node EN. The second relay node RN2 may determine that the quality of the channel is degraded when the strength of the reference signal received from the end node EN is less than the reference strength. As another example, the end node EN may receive the reference signal from the second relay node RN2 and may transmit the received reference signal strength information to the second relay node RN2. The second relay node RN2 can determine whether the channel quality is degraded based on the reception strength information of the reference signal received from the end node EN.

When the second relay node RN2 determines that the channel quality between the second relay node RN2 and the end node EN has deteriorated, the second relay node RN2 adds a new relay node to the existing path, You can extend the path. The second relay node RN2 may add a fourth relay node RN4 between the second relay node RN2 and the end node EN. The second relay node RN2 may transmit a message requesting the fourth relay node RN4 to relay the communication between the second relay node RN2 and the end node EN. The fourth relay node RN4 may transmit the downlink signal received from the second relay node RN2 to the end node EN. The fourth relay node RN4 may transmit the uplink signal received from the end node EN to the second relay node RN2.

The fourth relay node RN4 is added to the existing path so that the communication failure due to the deterioration of the channel quality between the second relay node RN2 and the end node EN can be overcome. However, according to the path extending method, since the hop number between the source node SN and the end node EN is increased, damage may occur in terms of throughput in the long term.

5 is a conceptual diagram showing a second embodiment in which a path is changed according to a path extending method. In the following description of the embodiment of FIG. 5, the description overlapping with FIG. 4 is omitted.

Referring to FIG. 5, the first relay node RN1 may detect degradation in channel quality between the first relay node RN1 and the second relay node RN2. The second relay node RN2 may be a destination node of the first relay node RN1. When the first relay node RN1 detects deterioration in channel quality, the first relay node RN1 may add a new relay node to the existing path. The first relay node RN1 may add a third relay node RN3 between the first relay node RN1 and the second relay node RN2. The third relay node RN3 may relay the communication between the first relay node RN1 and the second relay node RN2.

FIG. 6 is a conceptual diagram exemplarily showing a path change according to a path resetting method.

Referring to FIG. 6, the second relay node RN2 may detect degradation in channel quality between the second relay node RN2 and the end node EN. The second relay node RN2 may transmit a message reporting the channel quality degradation to the source node SN through the uplink signal. In this process, the first relay node RN1 can relay the communication between the second relay node RN2 and the source node SN. The source node SN may receive the report of the channel quality degradation and may reset the communication path between the source node SN and the end node EN. The source node SN may collect channel state information between the communication nodes of the multi-hop network, and may reset the communication path based on the collected channel state information. The source node SN is connected to the second path including the third relay node RN3 and the fourth relay node RN4 in the first path including the first relay node RN1 and the second relay node RN2, The communication path can be changed.

As the source node SN resets the communication path, the second relay node RN2 may not be involved in the communication relay. Accordingly, the problem of channel quality degradation between the second relay node RN2 and the end node EN can be solved. However, in the case of the path resetting method, it may take time for the source node SN to search for the reset second path. If the channel quality between the second relay node RN2 and the end node EN is restored within a short time, the reset second path may not have a better throughput than the existing first path .

7 is a conceptual diagram illustrating a routing method of a multi-hop network according to a first embodiment of the present invention.

Referring to FIG. 7, the first relay node RN1 and the second relay node RN2 in the first path can relay communication between the source node SN and the end node EN. The channel quality between the second relay node RN2 and the end node EN may be degraded due to an obstacle between the second relay node RN2 and the end node EN or for other reasons. The second relay node RN2 can detect a channel quality degradation based on the reception strength of the reference signal or the reference signal reception strength of the end node EN received from the end node EN.

The second relay node RN2 can change the path by the path extending method. For example, the second relay node RN2 may extend the path by adding another relay node to the first path. The second relay node RN2 may extend the first path by adding a relay node not included in the existing first path to the first path. For example, the second relay node RN2 may add the fourth relay node RN4 to the first path. The second relay node RM2 may add a fourth relay node RN4 between the second relay node RN2 and the end node EN. The fourth relay node RN4 may relay the communication between the second relay node RN4 and the end node EN.

The second relay node RN2 may send a message reporting the degradation of the channel quality. The first relay node RN1 may receive the message reporting the channel quality degradation from the second relay node RN2 and may forward the message to the source node SN. The source node SN may receive the message and perform an operation for path re-establishment.

The source node SN can determine the reset path by considering the channel state between the communication nodes of the multi-hop network. For example, periodically, the communication nodes can measure the mutual channel state and transmit the measurement results to the source node SN. As another example, the source node SN may request the communication nodes to measure the mutual channel status and send measurement results for the path reset.

The source node SN can re-establish the communication path between the source node SN and the end node EN, taking into consideration the channel state between the communication nodes. For example, the source node SN can search for a path that maximizes the communication throughput between the source node SN and the end node EN. However, the embodiment is not limited thereto, and the source node SN may reset the path in consideration of other parameters.

The source node SN may search the second path and determine whether to change the communication path to the second path. If the channel quality between the second relay node (RN2) and the end node (EN) is not restored during the reference time after the degradation of channel quality, the source node (SN) changes the path from the first path to the second path . The source node SN may transmit configuration information for the second path to the communication nodes to change the path. The setting information for the second path includes the identification information of the third relay node RN3 and the fourth relay node RN4 included in the second path and the identification information of the destination node of the third relay node RN3, RN4, and so forth. Communication between the source node SN and the end node EN can be made by the extended first path until the source node SN completes the resetting of the path.

As described above, if routing is performed by combining the path extension method and the path reset method, the disadvantages of both methods can be compensated. For example, if the channel quality degradation between the second relay node RN2 and the end node EN is not restored for a long time, the source node SN reestablishes the communication path, It is possible to prevent the number of hops between the end node EN and the end node EN from being set inefficiently large. Further, when the channel quality deterioration between the second relay node RN2 and the end node EN is recovered in a short time, the source node SN may not change the communication path to the second path. In this case, it is possible to prevent the route from being unnecessarily changed.

8 is a conceptual diagram illustrating a routing method of a multi-hop network according to a second embodiment of the present invention.

8, if an obstacle occurs between the second relay node RN2 and the end node EN or the channel quality between the second relay node RN2 and the end node EN may be degraded for some other reason have. The second relay node RN2 may extend the path and request the source node SN to reset the path.

The channel quality between the second relay node RN2 and the end node EN can be recovered while the source node SN is searching for the second path. For example, if the end node EN moves at a high speed or if the channel environment between the end node EN and the second relay node RN2 changes rapidly, before the reference time elapses, The channel quality between the RN2 and the end node EN can be restored.

The second relay node RN2 may request the source node SN to cancel the path reset after detecting the recovery of the channel quality before the reference time elapses after the channel quality has deteriorated. The source node SN may receive a cancellation request message of the path reset before the reference time elapses. In this case, the source node SN can stop the re-route operation. For example, the source node SN may stop searching for the second path. If the search for the second path is completed, the source node SN may not change the communication path from the first path to the second path. The source node SN may not transmit configuration information for the second path to the communication nodes.

When the channel quality between the second relay node RN2 and the end node EN is restored in a short time, the source node SN can maintain the previously set first path. Thus, it is possible to prevent the communication path from being set to the second path which is unnecessarily poor in communication efficiency than the first path. Also, the second relay node RN2 may return the first path to the extended full path. The second relay node RN2 may transmit a message requesting the fourth relay node RN4 to stop the communication relay. The fourth relay node RN4 may receive the message requesting the interruption of the communication relay and stop the communication relay between the second relay node RN2 and the end node EN. Therefore, if the channel quality is restored before the reference time elapses after the channel quality deteriorates, communication between the source node SN and the end node EN can be performed through the previously set first path.

9 is a graph comparing the performance of the path extending method and the path re-setting method.

In FIG. 9, the horizontal axis represents the ratio of the time period during which the channel quality is degraded (hereinafter referred to as "channel quality degradation time period") during the entire time. The vertical axis represents the average throughput of each scheme. Referring to FIG. 9, when the ratio of the channel quality degradation time interval is small as in (a), the path extending method may be advantageous compared to the path resetting method. In the case of the path extension method, the time required for the path change is smaller than the path reset method, and when the channel environment is restored, the path can be easily returned to the previous path. Therefore, when the channel quality deterioration occurs for a short time, the path extending method may be more advantageous than the path resetting method.

Referring to (b), the average throughputs of both schemes can be approximately the same as the channel quality degradation time interval ratio increases. The reference time used as a reference for determining whether the source node SN is changed by the path resetting method can be determined in consideration of the time when the average throughputs of the path extending method and the path resetting method are almost equal to each other.

Referring to the area (c), as the ratio of the channel quality degradation time period increases, the path reordering method may be more advantageous than the path extending method. According to the path extending method, if the number of hops is increased and the channel quality degradation time becomes longer, the efficiency may be lower than the path resetting method.

FIG. 10 is a graph for explaining the performance difference between the two schemes in the section (a) of FIG.

Referring to FIG. 10, in the path extending method, the delay time for changing the path may be shorter than the delay time of the path resetting method. On the other hand, the average data rate in the path changed by the path resetting method may be higher than the average data rate in the path according to the path extending method. As shown in FIG. 9A, when the channel quality degradation time is short, the data transmission amount may be larger than the path resetting method in the path extending method.

FIG. 11 is a graph for explaining the performance difference between the two schemes in the section (b) of FIG.

Referring to FIG. 11, when the channel quality degradation time reaches a critical point, the data transmission amount of each of the path resetting method and the path extending method can be substantially the same. The above-described reference time can be determined in consideration of the time when the performance of both schemes becomes almost equal.

FIG. 12 is a graph for explaining the performance difference between the two schemes in the interval (c) of FIG.

Referring to FIG. 12, as the channel quality degradation time becomes larger, the data transmission amount in the path resetting method can be further increased. If the channel quality degradation time increases, the efficiency of the path extending method may be lower than that of the path re-setting method because the hop count is increased and the average data transmission rate is low. Therefore, it is necessary to appropriately combine both schemes according to the size of the channel quality degradation time.

FIG. 13 is a graph comparing average throughputs of the path expansion method, the path resetting method, and the combination of both methods according to the speed of the end node EN.

13, the horizontal axis represents the speed of the end node EN, and the vertical axis represents the average throughput. If the speed of the end node EN is small, the rate of change of the channel environment may be low. Therefore, if the channel quality is degraded, the channel quality degradation time interval may be long. On the other hand, if the speed of the end node EN is large, the rate of change of the channel environment may be large. Therefore, if the channel quality is degraded, the channel quality degradation time interval may be short.

Referring to FIG. 13, if the channel quality degradation time is long because the speed of the end node EN is small, the path resetting method may perform better than the path extending method. In addition, the routing method according to the embodiment of the present invention changes the route by the route re-setting method when the reference time elapses, so that it can exhibit almost the same performance as the route re-setting method.

As the speed of the end node EN increases, the channel quality degradation time may gradually decrease. The routing method according to the embodiment of the present invention uses the changed route according to the route extending method before the reference time elapses and uses the changed route according to the route extending method after the lapse of the reference time, The performance can be more excellent.

If the speed of the end node EN is greater, the channel quality degradation time interval may be shorter than the critical point. Therefore, the path extension method may be more efficient than the path reset method. Since the routing method according to the embodiment of the present invention uses a route changed according to the route extension method before the reference time elapses, the performance is slightly better than the route extension method, and the performance can be significantly better than the route reset method.

The routing method of the multi-hop network according to the embodiment of the present invention has been described above with reference to FIG. 1 to FIG. According to the embodiment of the present invention, it is possible to efficiently change the communication path in the multi-hop network by appropriately combining the path extension method and the path reset method. The routing method is a method in which after the channel quality deteriorates, the path is changed according to the path extending method before the reference time passes, and the path is changed according to the path resetting method after the reference time passes, can do.

The methods according to the present invention can be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer readable medium may be those specially designed and constructed for the present invention or may be available to those skilled in the computer software.

Examples of computer readable media include hardware devices that are specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by the compiler 1, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. Be able to

Claims (1)

In a routing method performed in a multi-hop network,
At least one relay node included in the first path relaying communication between the source node and the end node;
Reporting the channel quality degradation to the source node when a first relay node included in the first path detects a channel quality degradation for a destination node designated in the first relay node;
The first relay node extending the first path by adding a second relay node between the first relay node and the destination node;
Searching for a reset path for the source node and the end node;
And changing, by the source node, the communication path with the end node to the discovered reset path if the channel quality is not restored until the reference time elapses after the channel quality deteriorates.

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