A relay selection method and system for multi-hop wireless sensor network coverage enhancement

Abstract

The present application relates to a kind of relay selection method and system for multi-hop wireless sensor network coverage enhancement, the multi-hop wireless sensor network includes source node, multiple relay nodes and destination node, there is no direct communication path between source node and destination node, the method includes the following steps: at the moment when source node sends data to destination node, trigger relay selection rule, the relay selection rule is as follows: select the relay node whose current memory capacity is less than upper limit, obtain the channel transmission gain between the relay node selected at this time and source node to form first set;Select the relay node whose current memory capacity is greater than zero, obtain the channel transmission gain between the relay node selected at this time and destination node to form second set;Obtain the maximum channel transmission gain in the union of first set and second set, and select the relay node corresponding to the maximum channel transmission gain as current relay.

Description

TECHNICAL FIELD

[0001] The present application relates to a relay selection method and system for multi-hop wireless sensor network coverage enhancement, and belongs to the technical field of relay node selection in wireless network. BACKGROUND

[0002] Wireless sensor network communication technology has the characteristics of low cost, flexible deployment, and multiple frequency bands, and can be quickly deployed on site to provide services for power business quickly and extend the coverage of power communication network. The conventional centralized single-hop star structure wireless sensor network has simple structure and strong reliability, but is limited by the communication distance of wireless sensor network and cannot achieve seamless coverage in underground and indoor environments. Therefore, wireless sensor network nodes need to be able to cooperate with transmission, and a multi-hop wireless sensor network is formed by relay method to improve the network coverage capability and achieve seamless coverage of power communication network. However, in the actual work of multi-hop wireless sensor network, how to select the most suitable relay to forward data is crucial to communication performance, and incorrect relay selection not only causes interruption of the entire communication link, but also causes waste of energy, greatly affecting the performance of the carried business.

[0003] At present, many methods have been proposed for relay selection in multi-hop communication. The most common one is the maximum worst channel selection method. The working principle of the maximum worst channel selection method is to select the relay with the worst channel quality in two hops as the forwarding relay. The basis for this method is the influence of the bucket effect, and the relay with the highest worst channel quality in two hops is selected to ensure the highest minimum transmission rate in two hops and the highest minimum transmission rate. However, this method does not consider the highest rate optimization, and in the case of generally good communication quality in two hops, the communication rate cannot be optimized. SUMMARY

[0004] In order to solve the problems existing in the prior art, the present application proposes a relay selection method and system for multi-hop wireless sensor network coverage enhancement.

[0005] The technical scheme of the present application is as follows:

[0006] On the one hand, the present application proposes a relay selection method for multi-hop wireless sensor network coverage enhancement, which includes a source node, a plurality of relay nodes and a destination node, and there is no direct communication path between the source node and the destination node. The method comprises the following steps:

[0007] At the moment when the source node sends data to the destination node, the relay selection rule is triggered, and the relay selection rule is as follows:

[0008] selecting a relay node with current memory capacity less than the upper limit, and obtaining a channel transmission gain between the selected relay node and the source node at this time to form a first set;

[0009] selecting a relay node with current memory capacity greater than zero, and obtaining a channel transmission gain between the selected relay node and the destination node at this time to form a second set;

[0010] obtaining the maximum channel transmission gain in the union of the first set and the second set, and selecting the relay node corresponding to the maximum channel transmission gain as the current relay.

[0011] As a preferred embodiment, the relay selection rule further comprises:

[0012] judging the size relationship between the channel transmission gain between the current relay and the source node and the channel transmission gain between the current relay and the destination node;

[0013] if the channel transmission gain between the current relay and the source node is greater than the channel transmission gain between the current relay and the destination node, then the current relay is in a receiving state;

[0014] if the channel transmission gain between the current relay and the destination node is greater than the channel transmission gain between the current relay and the source node, then the current relay is in a sending state.

[0015] As a preferred embodiment, the method further comprises:

[0016] when the current relay is in the receiving state, the memory capacity of the current relay is increased by one;

[0017] when the current relay is in the sending state, the memory capacity of the current relay is decreased by one.

[0018] In another aspect, the application further provides a relay selection system for multi-hop wireless sensor network coverage enhancement, wherein the multi-hop wireless sensor network comprises a source node, a plurality of relay nodes and a destination node, and there is no direct communication path between the source node and the destination node, and the system comprises:

[0019] a starting module for triggering a relay selection module to work when the source node sends data to the destination node, wherein the relay selection module comprises:

[0020] a first set selection unit for selecting a relay node with current memory capacity less than the upper limit, and obtaining a channel transmission gain between the selected relay node and the source node at this time to form a first set;

[0021] a second set selection unit for selecting a relay node with current memory capacity greater than zero, and obtaining a channel transmission gain between the selected relay node and the destination node at this time to form a second set;

[0022] The selecting unit is configured to obtain the maximum channel transmission gain in the union of the first set and the second set, and select the relay node corresponding to the maximum channel transmission gain as the current relay.

[0023] As a preferred embodiment, the relay selecting module further comprises:

[0024] The channel transmission gain unit is configured to determine the size relationship between the channel transmission gain between the current relay and the source node and the channel transmission gain between the current relay and the destination node.

[0025] The receiving state setting unit is configured to set the current relay to be in the receiving state when the channel transmission gain between the current relay and the source node is greater than the channel transmission gain between the current relay and the destination node.

[0026] The sending state setting unit is configured to set the current relay to be in the sending state when the channel transmission gain between the current relay and the destination node is greater than the channel transmission gain between the current relay and the source node.

[0027] As a preferred embodiment, the system further comprises:

[0028] The memory capacity updating module is configured to increase the memory capacity of the current relay by one when the current relay is in the receiving state, and decrease the memory capacity of the current relay by one when the current relay is in the sending state.

[0029] In another aspect, the present application further provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the relay selection method for coverage enhancement of a multi-hop wireless sensor network according to any one of the embodiments of the present application.

[0030] In another aspect, the present application further provides a computer readable storage medium having a computer program stored thereon, wherein the program is executable on a processor to implement the relay selection method for coverage enhancement of a multi-hop wireless sensor network according to any one of the embodiments of the present application.

[0031] The present application has the following advantages:

[0032] The present application provides a relay selection method and system for coverage enhancement of a multi-hop wireless sensor network, which takes the optimal channel transmission gain as a prerequisite, selects the relay node with the optimal channel transmission gain and the corresponding sending state under the condition that the bandwidth, sending power and noise are constant, and uses the memory space of the relay node as a limiting condition to prevent the system from being in the state of source node sending or relay sending for a long time, thereby providing the optimal system performance for the multi-hop wireless sensor network. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 Figure 1 is a flow chart of a method according to an embodiment of the present application;

[0034] Figure 2 Figure 2 is a diagram of a multi-hop wireless sensor network according to an embodiment of the present application;

[0035] Figure 3(a) is a diagram of a two-hop wireless sensor network transmission at time t=1 according to an embodiment of the present application;

[0036] Figure 3(b) is a diagram of a two-hop wireless sensor network transmission at time t=2 according to an embodiment of the present application;

[0037] Figure 3(c) is a diagram of a two-hop wireless sensor network transmission at time t=3 according to an embodiment of the present application;

[0038] Figure 3(d) is a diagram of a two-hop wireless sensor network transmission at time t=4 according to an embodiment of the present application;

[0039] Figure 4 Figure 4 is a diagram of a system according to another embodiment of the present application;

[0040] Figure 5 Figure 5 is a diagram of an electronic device according to another embodiment of the present application. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of the present application.

[0042] It should be understood that the step numbers used herein are only for the convenience of description, and are not limited to the execution sequence of the steps.

[0043] It should be understood that the terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0044] The terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0045] The term “and / or” refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes these combinations.

[0046] Example 1:

[0047] To address the problems existing in the background technology, this embodiment proposes a relay selection method for enhancing coverage of multi-hop wireless sensor networks.

[0048] See details Figure 2 The multi-hop wireless sensor network includes: (1) a source node S; and (2) a source node S and a relay node R. k Channel transmission gain between (3) A set of relay nodes C, of ​​which k relay nodes R k ∈C(1≤k≤K); Define Q k For R k memory space, Q k Satisfying 0≤Q k ≤L, where L is the upper limit of the relay node's memory; (4) Relay node R k+1 Transmission gain between destination node D and destination node D (5) Destination node D.

[0049] Source node S, multiple relay nodes R k (1 < k ≤ K) and the destination node D form a two-hop wireless sensor network system. There is no direct communication path between the source node S and the destination node D; data sent by the source node S needs to be forwarded through a relay in set C. The relay R... k Works in half-duplex mode.

[0050] See details Figure 1 The method provided in this embodiment specifically includes the following steps:

[0051] S100. When the source node S sends data to the destination node D, the relay selection rule is triggered.

[0052] The relay selection rules are as follows:

[0053] S201. First, select the current memory capacity Q from the relay set C. k For relay nodes <L, obtain the channel transmission gain between the selected relay node and the source node to form the first set:

[0054] S202, Continue selecting the current memory capacity Q from the relay set C. k For relay nodes with a value greater than 0, obtain the channel transmission gain between the selected relay node and the destination node to form a second set:

[0055] S203, obtaining the maximum channel transmission gain in the union of the first set and the second set, and selecting the relay node corresponding to the maximum channel transmission gain as the current relay R * Specifically,

[0056]

[0057] As an implementation manner of the embodiment, the relay selection rule further comprises:

[0058] S204, judging the size relationship between the channel transmission gain between the current relay R * and the source node S and the channel transmission gain between the current relay R * and the destination node D .

[0059] S205, if , the current relay R * is in a receiving state and is responsible for receiving data from the source node S.

[0060] S206, if , the current relay R * is in a sending state and is responsible for sending data to the destination node D.

[0061] As an implementation manner of the embodiment, the method further comprises:

[0062] When the current relay R * is in a receiving state, the memory capacity of the current relay is increased by one, indicating that one memory unit of data is received from the source node S.

[0063] When the current relay is in a sending state, the memory capacity of the current relay is decreased by one, indicating that one memory unit of data is sent to the destination node D by the relay R * .

[0064] The above steps S201-S206 are repeated at each moment when each source node S sends data to the destination node D.

[0065] Referring to the Shanon formula:

[0066]

[0067] Wherein, BW is the communication bandwidth, P is the transmission power, N0 is the background noise, and h is the channel transmission gain.

[0068] This embodiment takes optimal channel transmission gain as a premise. Under the conditions of fixed bandwidth, transmission power and noise, it selects the relay node with optimal channel transmission gain and the corresponding transmission state. At the same time, it uses the memory space of the relay node as a constraint to prevent the system from being in the same state of source node transmission or relay transmission for a long time. This can provide optimal system performance for multi-hop wireless sensor networks.

[0069] To help those skilled in the art further understand the technical solution of this embodiment, a specific operational example based on the relay selection method proposed in this embodiment is provided below:

[0070] refer to Figure 3(a) , 3(b) 3(c) and 3(d) Given a two-hop wireless sensor network system with three relay nodes (K=3), the memory limit of each relay node is L=3.

[0071] When the system starts running, i.e., at time t=1, assuming that each relay has no stored information, i.e., Q1=Q2=Q3=0, the following measurements are taken at this time:

[0072]

[0073] Because Q1 = Q2 = Q3 = 0, therefore: According to the selection principle in steps S203 to S206, R1 is selected as the current relay and is in the receiving state at time t=0. Therefore, Q1=0+1=1, as shown in Figure 3(a).

[0074] At time t=2, And the measurements show that:

[0075]

[0076] Therefore, at time t=2, R3 is selected as the current relay and is in the receiving state, so Q3=0+1=1, as shown in Figure 3(b).

[0077] At time t=3 And the measurements show that:

[0078]

[0079] Therefore, at time t=3, R1 is selected as the current relay and is in the receiving state, so Q1=1+1=2, as shown in Figure 3(c).

[0080] At time t=4 And the measurements show that:

[0081]

[0082] Thus at time t = 4, R1 is selected as the current relay and is in transmitting state, thus Q1 = 2 - 1 = 1, as shown in Fig. 3(d).

[0083] Embodiment Two:

[0084] Referring to Figure 4 The embodiment provides a relay selection system for coverage enhancement of a multi-hop wireless sensor network, the multi-hop wireless sensor network comprising a source node, a plurality of relay nodes and a destination node, the source node and the destination node not having a direct communication path, the system comprising:

[0085] A starting module, configured to trigger the relay selection module to work when the source node transmits data to the destination node; the module is used to realize the function of step S100 in Embodiment One, and thus will not be described here again;

[0086] The relay selection module comprises:

[0087] A first set selection unit, configured to select a relay node having a current memory capacity less than an upper limit, and obtain a channel transmission gain between the selected relay node and the source node to form a first set; the unit is used to realize the function of step S201 in Embodiment One, and thus will not be described here again;

[0088] A second set selection unit, configured to select a relay node having a current memory capacity greater than zero, and obtain a channel transmission gain between the selected relay node and the destination node to form a second set; the unit is used to realize the function of step S202 in Embodiment One, and thus will not be described here again;

[0089] A selection unit, configured to obtain a maximum channel transmission gain in a union of the first set and the second set, and select a relay node corresponding to the maximum channel transmission gain as a current relay; the unit is used to realize the function of step S203 in Embodiment One, and thus will not be described here again.

[0090] As a preferred embodiment of the embodiment, the relay selection module further comprises:

[0091] A channel transmission gain unit, configured to judge a size relationship between a channel transmission gain between the current relay and the source node and a channel transmission gain between the current relay and the destination node; the unit is used to realize the function of step S204 in Embodiment One, and thus will not be described here again;

[0092] A receiving state setting unit, configured to set the current relay in a receiving state if the channel transmission gain between the current relay and the source node is greater than the channel transmission gain between the current relay and the destination node; the unit is used to realize the function of step S205 in Embodiment One, and thus will not be described here again;

[0093] The sending state setting unit sets the current relay in a sending state if the channel transmission gain between the current relay and the destination node is greater than the channel transmission gain between the current relay and the source node. This unit is used to implement the function of step S206 in Embodiment One, and will not be described here again.

[0094] As a preferred embodiment of the present embodiment, the system further comprises:

[0095] The memory capacity updating module is configured to increase the memory capacity of the current relay by one when the current relay is in a receiving state, and decrease the memory capacity of the current relay by one when the current relay is in a sending state.

[0096] Embodiment Three

[0097] Figure 5 is a structural schematic diagram of an electronic device provided by the present embodiment. The electronic device is used for relay selection for multi-hop wireless sensor network coverage enhancement. As shown in Figure 5 the electronic device of the present embodiment at least includes a memory, a processor and a system bus, the memory includes a computer program stored thereon, and those skilled in the art can understand that, Figure 5 the electronic device structure shown in the above figure does not constitute a limitation on the electronic device, and can include more or fewer components than the figure, or combine certain components, or different component arrangements.

[0098] The following will be specifically described Figure 5 The various constituent components of the electronic device will be specifically introduced:

[0099] The memory can be used to store computer programs and modules, and the processor executes various functions and data processing of the electronic device by running the computer programs and modules stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application program required by a function (such as a sound playing function, an image playing function, etc.), etc.; the data storage area can store data (such as cache data) created according to the use of the electronic device, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, for example, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device.

[0100] The computer program comprising the relay selection method for multi-hop wireless sensor network coverage enhancement on the memory can be divided into one or more modules / units, which are stored in the memory and executed by the processor to realize the relay selection method for multi-hop wireless sensor network coverage enhancement and the like. The one or more modules / units can be a series of computer program instruction segments capable of completing a specific function, which are used to describe the execution process of the computer program in the electronic device. For example, the computer program can be divided into a starting module, a relay selection module and the like.

[0101] The processor is the control center of the electronic device, connects all parts of the electronic device through various interfaces and lines, executes various functions of the electronic device and processes data by running or executing the computer program and / or modules stored in the memory and calling the data stored in the memory, and thus monitors the overall state of the electronic device. Optionally, the processor can include one or more processing units; preferably, the processor can integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, application programs and the like, and the modem processor mainly processes wireless communication. It can be understood that the above-mentioned modem processor can also not be integrated into the processor.

[0102] The system bus is used to connect the internal functional components of the computer and can transmit data information, address information and control information, and its types can be, for example, PCI bus, ISA bus, CAN bus and the like. The instructions of the processor are transmitted to the memory through the bus, and the memory feeds back data to the processor, and the system bus is responsible for the interaction of data and instructions between the processor and the memory. Of course, the system bus can also access other devices, such as network interfaces, display devices and the like.

[0103] In the embodiment of the application, the computer program comprising the processing performed by the electronic device includes:

[0104] At the moment when the source node sends data to the destination node, the relay selection rule is triggered, and the relay selection rule is as follows:

[0105] The relay node with the current memory capacity less than the upper limit is selected, and the channel transmission gain between the selected relay node at this time and the source node is obtained to form a first set;

[0106] The relay node with the current memory capacity greater than zero is selected, and the channel transmission gain between the selected relay node at this time and the destination node is obtained to form a second set;

[0107] The maximum channel transmission gain in the union set of the first set and the second set is obtained, and the relay node corresponding to the maximum channel transmission gain is selected as the current relay.

[0108] Embodiment Four

[0109] The embodiment provides a computer readable storage medium, and a computer program is stored on the computer readable storage medium, and the computer program is executed by a processor to implement a relay selection method for multi-hop wireless sensor network coverage enhancement as described in any of the embodiments of the application.

[0110] In the embodiments of the present application, "at least one" means one or more, and "multiple" means two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the cases of A alone, A and B together, and B alone. Wherein A and B can be singular or plural. The character " / " generally represents that the associated objects before and after it are in an "or" relationship. "At least one of the following" and the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b, and c can be single or multiple.

[0111] Those skilled in the art can realize that the units and algorithm steps described in the embodiments disclosed in the present application can be realized by electronic hardware, computer software and combination of the electronic hardware and the computer software. Whether the functions are realized in hardware or software mode depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0112] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0113] In several embodiments provided in the present application, any function, if realized in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application or the parts of the technical solutions that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0114] The above description is only some embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, based on the content of the specification and drawings of the present application, are also included in the patent protection scope of the present application.

Claims

1. A relay selection method for multi-hop wireless sensor network coverage enhancement, the multi-hop wireless sensor network comprising a source node, a set of relay nodes consisting of a plurality of relay nodes C wherein k relay nodes ∈ C , and a destination node, there being no direct communication path between the source node and the destination node, characterized in that The method includes the following steps: When the source node sends data to the destination node, a relay selection rule is triggered, and the relay selection rule is as follows: In the relay node set C The relay node with the current memory capacity less than the upper limit is selected, and a channel transmission gain between the selected relay node and the source node at this time is obtained to form a first set; In the relay node set C The relay nodes with the current memory capacity greater than zero are selected, and a second set composed of the channel transmission gains between the selected relay nodes and the destination node at this time is obtained. Obtain the largest channel transmission gain in the union of the first set and the second set, and select the relay node corresponding to the largest channel transmission gain as the current relay; The relay selection rules also include: Determine the relationship between the channel transmission gain between the current relay and the source node, and between the current relay and the destination node; If the channel transmission gain between the current relay and the source node is greater than the channel transmission gain between the current relay and the destination node, then the current relay is put into receiving mode. If the channel transmission gain between the current relay and the destination node is greater than the channel transmission gain between the current relay and the source node, then the current relay is put into the transmitting state. The method further includes: When the current relay is in receiving mode, increment the memory capacity of the current relay by one. When the current relay is in the sending state, decrease the memory capacity of the current relay by one.

2. A relay selection system for enhancing coverage in multi-hop wireless sensor networks, wherein the multi-hop wireless sensor network includes a source node and a set of relay nodes. C Among them, k relay nodes ∈ C There is no direct communication path between the source node and the destination node, characterized in that... The system includes: The startup module is used to trigger the relay selection module to operate when the source node sends data to the destination node. The relay selection module includes: The first set selection unit is used to select relay nodes from the set. C Select relay nodes whose current memory capacity is less than the upper limit, and obtain the channel transmission gain between the selected relay nodes and the source node to form the first set; The second set selection unit is used to select relay nodes from the set. C Select relay nodes whose current memory capacity is greater than zero, and obtain the channel transmission gain between the selected relay nodes and the destination node to form a second set; The selection unit is used to obtain the maximum channel transmission gain in the union of the first set and the second set, and select the relay node corresponding to the maximum channel transmission gain as the current relay. The relay selection module further includes: The channel transmission gain unit is used to determine the relationship between the channel transmission gain between the current relay and the source node, and between the current relay and the destination node. If the channel transmission gain between the current relay and the source node is greater than the channel transmission gain between the current relay and the destination node, the receiving state setting unit sets the current relay to the receiving state. If the channel transmission gain between the current relay and the destination node is greater than the channel transmission gain between the current relay and the source node, the transmission state setting unit sets the current relay to the transmission state. The system also includes: The memory capacity update module is used to increment the memory capacity of the current relay by one when the current relay is in the receiving state, and decrement the memory capacity of the current relay by one when the current relay is in the transmitting state.

3. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the relay selection method for coverage enhancement of multi-hop wireless sensor networks as described in claim 1.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the relay selection method for coverage enhancement of multi-hop wireless sensor networks as described in claim 1.

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