Wireless communication system

Abstract

The embodiment of the present invention provides a wireless communication method and system, wherein the method includes: a communication terminal device sends a route query RREQ data frame; if the communication terminal device receives a route reply RREP data frame sent by a gateway within a preset time period, the route discovery is successful; after the route discovery is successful and the route connection is successfully established, the communication terminal device transmits data according to the application layer data frame structure; after the communication terminal device completes the data transmission, it enters a sleep state and uses an adaptive sleep algorithm to adjust the sleep time in real time. The embodiment of the present invention has the characteristics of no manual deployment, ultra-low power consumption, and can meet a large number of communication loads. It solves the practicality, reliability and stability of the communication equipment under conditions such as lack of infrastructure and harsh environment. It does not require a cellular network and can perform self-organizing network coverage based on itself.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and more specifically, to a wireless communication system. Background Art

[0002] In construction sites, if communications are carried out on site, the following challenges are usually faced: lack of infrastructure and no cellular network coverage for the time being; the accumulation of debris at the work site is not suitable for the deployment of communication nodes on the ground; communication nodes face challenges such as power consumption, because the construction site must meet the condition of not requiring maintenance for a long time; there are many construction workers and the communication load is heavy.

[0003] Therefore, in order to solve the problems of practicality, reliability and stability of communication equipment under conditions such as lack of infrastructure and harsh environment, it is urgent to provide a wireless communication method or system that does not require manual deployment, has ultra-low power consumption, and can meet a large number of communication loads. Summary of the invention

[0004] In order to solve or at least partially solve the above problems, an embodiment of the present invention provides a line communication method and system.

[0005] In a first aspect, an embodiment of the present invention provides a wireless communication method, including:

[0006] The communication terminal device sends a route query RREQ data frame;

[0007] If the communication terminal device receives the route reply RREP data frame sent by the gateway within the preset time period, the route discovery is successful;

[0008] After the route discovery is successful and the route connection is successfully established, the communication terminal device transmits data according to the application layer data frame structure;

[0009] After completing data transmission, the communication terminal device enters a sleep state and uses an adaptive sleep algorithm to adjust the sleep time in real time.

[0010] The method of adjusting the sleep time in real time by using an adaptive sleep algorithm is as follows:

[0011] Calculate the importance of each communication terminal device by using a neighbor adaptation strategy and / or a location awareness strategy;

[0012] Based on the importance of each communication terminal device, a load balancing algorithm is used to calculate the sleep time of each communication terminal device.

[0013] Wherein, after the step of sending the route query RREQ data frame by the communication terminal device, the step further includes:

[0014] If the communication terminal device does not receive the route reply RREP data frame sent by the gateway within the preset time period, the route query RREQ data frame is resent, and the waiting time for response is doubled. If the communication terminal device receives the route reply RREP data frame sent by the gateway within the waiting time for response, the route discovery is successful; or,

[0015] If the communication terminal device does not receive the routing reply RREP data frame sent by the gateway within the waiting response time, the gateway is marked as unreachable in the routing table and the application layer is notified. At the same time, the communication terminal device enters the sleep state according to the adaptive sleep algorithm.

[0016] The RREQ data frame includes the following fields: frame type, sequence number, source address, destination address, routing path, forwarded quantity and power;

[0017] The RREP data frame and the RREQ data frame have the same frame structure;

[0018] The application layer data frame structure includes the following fields: device information, location information and control information.

[0019] Among them, it also includes:

[0020] During the route discovery process, the communication terminal device performs route updates according to the received or forwarded RREQ data frames and RREP data frames, caches the latest route information to the route table, and updates the route generation time;

[0021] The routing table includes the following fields: network address, network mask, gateway, interface and metric.

[0022] The use of a neighbor adaptation strategy and / or a location awareness strategy to calculate the importance of each communication terminal device is specifically as follows:

[0023] The importance of each communication terminal device obtained based on the neighbor adaptation strategy is set to P1, and the calculation formula of P1 is:

[0024]

[0025] and / or,

[0026] The importance of each communication terminal device obtained based on the location awareness strategy is set to P2, and the calculation formula of P2 is:

[0027]

[0028] Wherein, m is the number of neighbors of the communication terminal device, and d is the number of hops in the routing table.

[0029] The sleep time of each communication terminal device is calculated based on the importance of each communication terminal device using a load balancing algorithm, specifically:

[0030] Through the forwarding records, the value with the largest forwarding quantity among the communication nodes directly connected to the communication terminal device is obtained, which is recorded as N;

[0031] The sleep time of the current communication terminal device is calculated using the following formula:

[0032]

[0033] Wherein, P is the importance of the communication terminal device, T is the cycle length, and n is the value of the forwarded quantity field in the data frame.

[0034] In a second aspect, an embodiment of the present invention provides a wireless communication system, comprising: a terminal device network composed of a plurality of communication terminal devices executing the wireless communication method according to the first aspect, a gateway and a control center, wherein:

[0035] Each communication terminal device is carried by a person and moves with the free movement of the person, and each of the communication terminal devices communicates with the gateway through a single wireless channel;

[0036] The gateway has a multi-channel wireless data transceiver function, which is used to forward the data sent by the terminal device network to the control center to realize the communication between the communication terminal device and the control center;

[0037] The control center is used to obtain information sent by each communication terminal device and issue instructions to the communication terminal device.

[0038] Wherein, the communication terminal device includes: a power module, a main control unit and a wireless transceiver unit, and the gateway includes: a power module, a main control unit and multiple wireless transceiver units.

[0039] In a third aspect, an embodiment of the present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the wireless communication method provided in the first aspect.

[0040] The wireless communication method and system provided by the embodiments of the present invention have the characteristics of no manual deployment, ultra-low power consumption, and the ability to meet a large number of communication loads. They solve the problems of practicality, reliability, and stability of communication equipment under conditions such as lack of infrastructure and harsh environment. They do not require a cellular network and can provide self-organizing network coverage on their own. At the same time, they solve problems and demands such as poor ground signals, energy consumption challenges, and communication load. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 A schematic diagram of a wireless communication method according to an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of a wireless self-organizing network structure provided by an embodiment of the present invention;

[0044] Figure 3 Schematic diagram of the structure of a single communication terminal device

[0045] Figure 4 Schematic diagram of the gateway structure

[0046] Figure 5 Duty cycle for communication terminal equipment;

[0047] Figure 6 It is a schematic diagram of the two quantities of number of neighbors and number of hops;

[0048] Figure 7 A schematic diagram of a flow chart of a wireless communication method provided by another embodiment of the present invention;

[0049] Figure 8 A schematic diagram of an actual application scenario of the wireless communication method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Figure 1 A schematic flow chart of a wireless communication method provided by an embodiment of the present invention includes:

[0052] Step 100, the communication terminal device sends a route query RREQ data frame;

[0053] Specifically, in order to solve the problems of practicality, reliability and stability of communication equipment under conditions such as lack of infrastructure and harsh environment, the embodiment of the present invention adopts a wireless self-organizing network structure.

[0054] Wireless self-organizing networks have the characteristics of dynamic mesh topology and multi-hop relay transmission of information. There are multiple redundant information paths between any two communication nodes in the network. Even if a communication node in the middle fails or is damaged, the information transmission path can still be repaired by relying on the collaboration between the surrounding nodes to achieve reliable communication. Based on the above characteristics, wireless self-organizing networks are suitable for use in harsh environments or scenarios without cellular networks. By deploying several wireless communication nodes on site, a highly stable and resistant information transmission channel can be established between operators. The use of wireless self-organizing networks will make it very easy to perceive the current location information of the staff and to issue retreat orders from the console.

[0055] Figure 2 The wireless communication method provided by the embodiment of the present invention is applied in the following aspects: Figure 2 In the wireless self-organizing network structure shown, the wireless self-organizing network structure includes three parts: a terminal device network, a gateway and a control center.

[0056] In the network structure, each communication terminal device is carried by a person and moves with the person's free movement, so the terminal device network structure changes over time.

[0057] Figure 3 It is a structural diagram of a single communication terminal device, such as Figure 3 As shown, each communication terminal device includes: a power module 310, a main control unit 320 and a wireless transceiver unit 330, which transmits and receives data through a single wireless channel.

[0058] The gateway serves to connect the communication terminal equipment and the control center. Figure 4 This is a schematic diagram of the gateway structure. Figure 4 As shown, the gateway includes a power module 410, a main control unit 420 and multiple wireless transceiver units 430. Unlike the communication terminal device, the gateway has a multi-channel wireless data transceiver function, which is used to forward the data sent by the terminal device network to the control center to realize the communication between the communication terminal device and the control center.

[0059] The control center is used to obtain information sent by each communication terminal device and issue instructions to the communication terminal device when necessary.

[0060] In summary, in this embodiment, the wireless self-organizing network includes several communication terminal devices, a gateway and a control center. Each staff member will wear a communication terminal device, and the network formed by each communication terminal device can cover the signal to most areas, so that each communication terminal device can communicate with the gateway. The gateway is directly connected to the control center, so that the control center can directly obtain the device information of each staff member, and can also directly issue instructions when necessary.

[0061] Based on the above wireless self-organizing network structure, when the communication terminal device starts working, it sends a route query RREQ data frame to the gateway to perform route discovery.

[0062] The structure of the RREQ data frame is shown in Table 1. The RREQ data frame includes the following fields: frame type, sequence number, source address, destination address, routing path, forwarded quantity and power.

[0063] Table 1 Structure of RREQ data frame

[0064] Frame Type Serial Number Source Address Destination Address Routing Path Number of forwarded Power ……

[0065] The meanings of the fields are:

[0066] Frame type: frame type;

[0067] Sequence number: unique identifier of the frame;

[0068] Source address: the source address of the data frame;

[0069] Destination address: destination address of the data frame;

[0070] Routing path: the specific path from the source address to the destination address;

[0071] Number of forwarded: the number of routes that the current terminal has forwarded;

[0072] Battery level: Remaining battery power.

[0073] Step 101: If the communication terminal device receives a route reply RREP data frame sent by the gateway within a preset time period, the route discovery is successful;

[0074] Specifically, the ideal situation is that the gateway successfully receives the RREQ data frame sent by the communication terminal device and replies with a RREP data frame. The communication terminal device receives the route reply RREP data frame sent by the gateway within a preset time period t, and the route discovery is successful at this time.

[0075] Furthermore, if the communication terminal device does not receive the route reply RREP data frame sent by the gateway within the preset time period, the route query RREQ data frame is resent, and the waiting time for response is doubled (i.e., t*2). If the communication terminal device receives the route reply RREP data frame sent by the gateway within the waiting time for response, the route discovery is successful; or,

[0076] If the communication terminal device does not receive the routing reply RREP data frame sent by the gateway within the waiting response time, the gateway is marked as unreachable in the routing table and the application layer is notified. At the same time, the communication terminal device enters the sleep state according to the adaptive sleep algorithm.

[0077] The RREP data frame and the RREQ data frame have the same frame structure.

[0078] In one embodiment, the wireless communication method further includes:

[0079] During the route discovery process, the communication terminal device performs route updates according to the received or forwarded RREQ data frames and RREP data frames, caches the latest route information to the route table, and updates the route generation time;

[0080] The routing table includes the following fields: network address, network mask, gateway, interface and metric.

[0081] Specifically, in this embodiment, each communication terminal device not only has its own data transmission task, but also helps forward network data from other communication terminal devices. Each communication terminal device maintains a routing table locally, storing the reachable network destination address range and routing information on how to reach it. The routing table structure is shown in Table 2.

[0082] Table 2 Routing table structure

[0083] Network Address Network Mask Gateway interface Number of hops

[0084] The meanings of the fields are:

[0085] Network address, network mask: The network address and network mask together determine the reachable destination address range;

[0086] Gateway: defines the next-hop server to which the data packet is sent for a specific network destination address;

[0087] Interface: The network interface used by the local computer to send data packets for a specific network destination address;

[0088] Hop count: Indicates the cost of the route, usually representing the number of hops required to reach the destination address. One hop represents passing through one router.

[0089] When a communication terminal sends data, it can reach the designated location according to the path in the routing table.

[0090] During the route discovery process, the communication terminal device performs route updates according to the received or forwarded RREQ data frames and RREP data frames, caches the latest route information to the route table, and updates the route generation time.

[0091] Step 102: After the route discovery is successful and the route connection is successfully established, the communication terminal device transmits data according to the application layer data frame structure;

[0092] Specifically, after the route discovery is successful and the route connection is established, the communication terminal device notifies the application layer that it can start transmitting specific data, which is customized by the user. Commonly used data include the location information of the operator, the device status information of the current device, and the instructions issued by the control center. Since the application layer data is highly customizable, this can be adjusted according to actual usage needs.

[0093] It is worth noting that, in this embodiment, the application layer data frame structure is as shown in Table 3, including the following fields: device information, location information and control information.

[0094] Table 3 Application layer data frame structure

[0095] Device Information Location Information Control Information ……

[0096] Among them, device information includes the current working status of the device, location information specifically refers to longitude, latitude and altitude, and control information is needed when conveying instructions.

[0097] Step 103: After completing the data transmission, the communication terminal device enters a sleep state and uses an adaptive sleep algorithm to adjust the sleep time in real time.

[0098] Specifically, in this embodiment, each communication terminal device not only has its own data transmission task, but also helps forward network data from other communication terminal devices. In order to make all communication terminals work longer and reduce maintenance costs, the terminals need to sleep from time to time to save power. The embodiment of the present invention proposes an adaptive sleep algorithm, which can adjust the sleep time in real time according to the current geographical location of the communication terminal device and the strength of the network signal.

[0099] Figure 5It is the duty cycle of the communication terminal equipment. It can be seen that the sleep time is different each time. This is because after the terminal successfully transmits data, the optimal sleep time will be calculated according to the adaptive sleep algorithm.

[0100] In order to extend the use time of communication terminal devices, we need these communication terminal devices to sleep when they are not working to save power. In actual application scenarios, staff wear terminals, and their positions change over time, so the wireless network structure is constantly changing. In order to ensure that the sleep of each communication terminal device does not affect the operation of the entire system network, before sleep, it is necessary to calculate the optimal sleep time based on the current position and importance of the communication terminal device in the network. In actual application scenarios, if a communication terminal device is closer to the gateway and there are no other nodes around, then the importance of this communication terminal device is very high, because the communication between the remaining terminals and the gateway must rely on it to forward, and obviously the sleep time of these terminals needs to be relatively short.

[0101] To this end, the embodiment of the present invention adopts an adaptive sleep algorithm. First, the importance of each communication terminal device is calculated using a neighbor adaptive strategy and / or a location awareness strategy; based on the importance of each communication terminal device, a load balancing algorithm is used to calculate the sleep time of each communication terminal device. The number of neighbors of each communication terminal device is represented as m, and the field "number of hops" in the routing table is recorded as d. Figure 6 A schematic diagram of the two quantities: the number of neighbors and the number of hops.

[0102] The neighbor adaptation strategy is mainly based on the location of the terminal in a network structure and the number of communication node neighbors around the current terminal.

[0103] If the number of neighbors m is large, it means that the importance of the current communication terminal device is not that high, and the surrounding nodes can be appropriately allowed to implement the forwarding function. Here, the load balancing strategy is used to select other suitable nodes, so the communication terminal device can have a longer sleep time.

[0104] If the number of neighbors m is small, it is necessary to determine whether the current communication terminal device can be directly connected to the gateway. If no routing entry corresponding to the gateway is found in the routing table, or there is a routing record but the value of d is relatively large, it means that the communication terminal device is far away from the device and needs to rely on other terminals to communicate with the gateway. In addition, there are few neighbor nodes. Such nodes are called "isolated nodes". For such nodes, the sleep time can be longer because they are not very important to the network.

[0105] If there is a gateway entry in the routing table and d=0, and the number of neighbors m is small, it means that the current node is very important, because other terminals need to use the current node to forward data to achieve communication with the gateway, so the sleep time needs to be relatively short.

[0106] In one embodiment, the importance of each communication terminal device obtained based on the neighbor adaptation strategy is set to P1, and the calculation formula of P1 is:

[0107]

[0108] Location-aware strategies:

[0109] The geographical location of the terminal is also an important factor in determining its sleep time. Judging by the current geographical location of the terminal, the farther away from the gateway, the lower its importance.

[0110] If d = 0 or the d value is small, it means that the distance to the gateway relay device is close. For this type of terminal node, the importance is relatively higher, so the sleep time is shorter;

[0111] If the d value is large or does not exist, it means that the terminal is farther away from the relay device and the importance of this type of terminal is relatively lower, so the sleep time can be longer.

[0112] In order to quantify the importance of these nodes, the value obtained based on the location awareness strategy is set as P2, and the calculation formula of P2 is:

[0113]

[0114] For each node, the importance can be calculated based on the neighbor adaptation strategy or the location awareness strategy alone, or the importance calculated based on the neighbor adaptation strategy and the location awareness strategy can be combined to obtain the importance of each node.

[0115] When choosing which nodes to sleep and which nodes to work, load balancing is required. Because each terminal node will be part of the network transmission, it needs to forward messages transmitted by other nodes, which requires energy. The value of the "Number of Forwarded" field in the data frame is recorded as n. The general principle is that under the same consideration conditions, nodes with large n values ​​are given priority to sleep for a longer time, and nodes with small n values ​​sleep for a shorter time or continue to work.

[0116] When calculating the sleep time, we calculate the sleep time within a period T, where T is set to 10 minutes. In order to ensure the power consumption of the communication node, the specific sleep time calculation steps are as follows: calculate the importance P value of the communication terminal device; obtain the value N with the largest forwarding number among the communication nodes directly connected to the communication terminal device through forwarding records; then the sleep time of the current node is:

[0117] The wireless communication method provided by the embodiment of the present invention has the characteristics of no need for manual deployment, ultra-low power consumption, and the ability to meet a large number of communication loads. It solves the problems of practicality, reliability, and stability of communication equipment under conditions such as lack of infrastructure and harsh environment. It does not require a cellular network and can provide self-organizing network coverage on its own. It also solves problems and demands such as poor ground signals, energy consumption challenges, and communication load.

[0118] Figure 7 A schematic flow chart of a wireless communication method provided by another embodiment of the present invention.

[0119] Figure 8 Schematic diagram of actual application scenario of the wireless communication method provided by an embodiment of the present invention. Figure 8 As shown in the figure, a practical application case is the smart construction site. The safety helmets worn by workers are integrated with the communication terminal of the wireless ad hoc network system, the gateway relay equipment is installed on the tower crane, and the command center is located in the on-site command building next to the construction site. Through such a system, the command center can obtain the location, height, posture and other data of the workers at regular intervals to provide a guarantee for the safety of the workers; at the same time, when encountering special circumstances, the command center can also send commands directly to each worker, greatly improving the communication efficiency.

[0120] Another embodiment of the present invention provides a wireless communication system, comprising: a terminal device network composed of a plurality of communication terminal devices executing the wireless communication method as described above, a gateway and a control center, wherein:

[0121] Each communication terminal device is carried by a person and moves with the free movement of the person, and each of the communication terminal devices communicates with the gateway through a single wireless channel;

[0122] The gateway has a multi-channel wireless data transceiver function, which is used to forward the data sent by the terminal device network to the control center to realize the communication between the communication terminal device and the control center;

[0123] The control center is used to obtain information sent by each communication terminal device and issue instructions to the communication terminal device.

[0124] For understanding of the communication terminal equipment in the embodiment of the present invention, reference may be made to the aforementioned wireless communication method embodiment, which will not be described in detail here.

[0125] Wherein, the communication terminal device includes: a power module, a main control unit and a wireless transceiver unit, and the gateway includes: a power module, a main control unit and multiple wireless transceiver units.

[0126] The wireless communication system provided by the embodiment of the present invention has the characteristics of no need for manual deployment, ultra-low power consumption, and the ability to meet a large number of communication loads. It solves the problems of practicality, reliability, and stability of communication equipment under conditions such as lack of infrastructure and harsh environment. It does not require a cellular network and can provide self-organizing network coverage by itself. At the same time, it solves problems and demands such as poor ground signals, energy consumption challenges, and communication load.

[0127] An embodiment of the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the wireless communication method provided by the above-mentioned method embodiments is implemented, for example, including: a communication terminal device sends a route query RREQ data frame; if the communication terminal device receives a route reply RREP data frame sent by a gateway within a preset time period, the route discovery is successful; after the route discovery is successful and the route connection is successfully established, the communication terminal device transmits data according to the application layer data frame structure; after completing the data transmission, the communication terminal device enters a sleep state, and uses an adaptive sleep algorithm to adjust the sleep time in real time.

[0128] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0129] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wireless communication system, characterized in that: include: A terminal equipment network consisting of several communication terminal equipment, gateways and control centers, among which: Each communication terminal device is carried by a person and moves with the free movement of the person, and each of the communication terminal devices communicates with the gateway through a single wireless channel; The gateway has a multi-channel wireless data transceiver function, which is used to forward the data sent by the terminal device network to the control center to realize the communication between the communication terminal device and the control center; The control center is used to obtain information sent by each communication terminal device and issue instructions to the communication terminal device; The wireless communication method of the wireless communication system includes: The communication terminal device sends a route query RREQ data frame; If the communication terminal device receives the route reply RREP data frame sent by the gateway within the preset time period, the route discovery is successful; After the route discovery is successful and the route connection is successfully established, the communication terminal device transmits data according to the application layer data frame structure; After completing the data transmission, the communication terminal device enters a sleep state and uses an adaptive sleep algorithm to adjust the sleep time in real time; The adaptive sleep algorithm is used to adjust the sleep time in real time: Calculate the importance of each communication terminal device by using a neighbor adaptation strategy and / or a location awareness strategy; Based on the importance of each communication terminal device, a load balancing algorithm is used to calculate the sleep time of each communication terminal device; The wireless communication method of the wireless communication system further includes: During the route discovery process, the communication terminal device performs route updates according to the received or forwarded RREQ data frames and RREP data frames, caches the latest route information to the route table, and updates the route generation time; Wherein, the routing table includes the following fields: network address, network mask, gateway, interface and hop number; The use of a neighbor adaptation strategy and / or a location awareness strategy to calculate the importance of each communication terminal device is specifically as follows: The importance of each communication terminal device obtained based on the neighbor adaptation strategy is set to P1, and the calculation formula of P1 is: and / or, The importance of each communication terminal device obtained based on the location awareness strategy is set to P2, and the calculation formula of P2 is: Wherein, m is the number of neighbors of the communication terminal device, and d is the number of hops in the routing table.

2. The wireless communication system according to claim 1, characterized in that: The communication terminal device comprises: a power module, a main control unit and a wireless transceiver unit, and the gateway comprises: a power module, a main control unit and a plurality of wireless transceiver units.

3. The wireless communication system according to claim 1, characterized in that: After the step of sending the route query RREQ data frame by the communication terminal device, the method further includes: If the communication terminal device does not receive the route reply RREP data frame sent by the gateway within the preset time period, the route query RREQ data frame is resent, and the waiting time for response is doubled. If the communication terminal device receives the route reply RREP data frame sent by the gateway within the waiting time for response, the route discovery is successful; or, If the communication terminal device does not receive the routing reply RREP data frame sent by the gateway within the waiting response time, the gateway is marked as unreachable in the routing table and the application layer is notified. At the same time, the communication terminal device enters the sleep state according to the adaptive sleep algorithm.

4. The wireless communication system according to claim 1, characterized in that: The RREQ data frame includes the following fields: frame type, sequence number, source address, destination address, routing path, forwarded quantity and power; The RREP data frame and the RREQ data frame have the same frame structure; The application layer data frame structure includes the following fields: device information, location information and control information.

5. The wireless communication system according to claim 1, characterized in that: Based on the importance of each communication terminal device, the sleep time of each communication terminal device is calculated by using a load balancing algorithm, specifically: Through the forwarding records, the value with the largest forwarding quantity among the communication nodes directly connected to the communication terminal device is obtained, which is recorded as N; The sleep time of the current communication terminal device is calculated using the following formula: Wherein, P is the importance of the communication terminal device, T is the cycle length, and n is the value of the forwarded quantity field in the data frame.

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