Short-wave communication networking method capable of autonomously selecting communication mode

Abstract

The invention discloses a short-wave communication networking method capable of autonomously selecting a communication mode, which specifically comprises the following steps: short-wave stations form a transfer station wireless network, a source user and a target user are set to be in a direct connection mode, frequency selection and link establishment are carried out, and if the link establishment is successful, a subsequent communication service is executed; if the switching fails, the source user is switched from a direct connection mode to a forwarding mode, the source user joins in a forwarding station wireless network and sends forwarding wake-up request instructions to a plurality of short-wave stations, the short-wave stations send wake-up request instructions with different frequencies to the target user after receiving the instructions, and the target user carries out diversity collection and processing on the instructions and joins in the forwarding station wireless network; sending a message forwarding awakening response instruction to the source user through the short-wave station, successfully preparing a message forwarding mode, and executing a subsequent communication service; and after the communication service is completed or in a service idle state, dismantling the network access link, and switching from the message forwarding mode to the direct connection mode. According to the invention, the success rate of the communication service is improved, the equipment fault influence is reduced, and large-scale networking is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of shortwave communication, and more specifically to a shortwave communication networking method for autonomously selecting a communication mode. Background Art

[0002] With the mature development of shortwave communication equipment, shortwave communication is developing in the direction of networking and systematization. Improving the coverage and communication success rate of shortwave communication and improving user experience satisfaction by integrating various functional shortwave networking technologies has become the current development direction of shortwave communication systems. Shortwave communication is usually carried out by shortwave mobile users through shortwave stations. Shortwave stations are generally composed of shortwave antennas, shortwave receivers, shortwave transmitters, shortwave signal processing equipment, etc., and generally use fixed infrastructure with high-power and large antennas; shortwave mobile users are generally composed of shortwave antennas, shortwave radio stations, etc., and generally use small antennas and low-power mobile communication devices, such as shortwave communication vehicles.

[0003] Modern shortwave networking communication systems are generally composed of a fixed side consisting of multiple shortwave stations and a mobile side consisting of multiple shortwave mobile users. The fixed side provides wireless coverage, network access, business communication and other signal relay functions for shortwave mobile users with shortwave wireless communication capabilities.

[0004] Approximate solution 1 is a patent (CN106102132A) that discloses a shortwave networking implementation method with intelligent frequency selection and diversity. The access node and the diversity processing center are connected through a wired IP bearer network. When mobile users communicate with each other, the mobile users first successfully establish a link with the access node through intelligent frequency selection. After the wireless link is successfully established, at the link frequency, the diversity processing center specifies other nodes other than the access node that has established the wireless link to assist in diversity reception. The diversity processing center aggregates the signals received by each node through the wired network for combined decoding. Then the diversity processing center sends the combined information to the target mobile user through the access node.

[0005] Approximate solution 2 is that the patent (CN114040468A) discloses a shortwave automatic forwarding method and device, which establishes a relay station network including multiple shortwave relay stations according to the initiator and destination of the message data, and the current relay station sends a link establishment request including the initiator, routing value and destination to other relay stations in the relay station network; the relay station that receives the link establishment request parses the destination from the link establishment request, and if the relay station that receives the link establishment request is the destination, the link establishment with the initiator is completed to form a communication link; otherwise, forwarding information is added to the link establishment request, and the link establishment request with the added forwarding information is sent out, and the forwarding information includes the information of the relay station that receives the link establishment request and its routing weight value.

[0006] In the prior art of the above patent, the approximate solution one is that the user is processed by the node and the diversity processing center before reaching the user, and the communication efficiency is low. The relay station of the approximate solution two can only provide point-to-point linear security, and both have high requirements on the channel link quality, high channel occupancy, and low communication service success rate and communication efficiency. Summary of the invention

[0007] The present invention aims to overcome at least one defect in the prior art and provide a shortwave communication networking method with autonomous selection of communication modes, which is used to solve the problems of high requirements on channel link quality, high channel occupancy, low communication service success rate and low communication efficiency.

[0008] The technical method adopted by the present invention is a shortwave communication networking method for autonomously selecting a communication mode, comprising the following steps: Step S100: The shortwave stations form a relay station wireless network, and the source user and the target user are set to direct mode; Step S200: The source user calls the target user in direct mode to establish a communication channel; Step S300: Determine whether the communication channel meets the minimum signal-to-noise ratio condition for link establishment. If so, the frequency selection and link establishment are successful, and subsequent communication services are performed; if not, the frequency selection and link establishment fails, and the source user switches the mode from the direct mode to the forwarding mode; Step S400: The source user joins the wireless network of the relay station within the working frequency band and sends a relay wake-up request instruction to multiple shortwave stations; Step S500: After receiving the signal forwarding wake-up request instruction, multiple shortwave stations send different frequency wake-up request instructions to the target user. The target user processes the wake-up request instructions in a diversity manner, switches the direct mode to the signal forwarding mode, and joins the signal forwarding station wireless network within the working frequency band. Step S600: The target user sends a forwarding wake-up response instruction to the source user through the shortwave station, and the forwarding mode is successfully prepared to execute subsequent communication services; Step S700: After completing the communication service, or in the service idle state, the source user initiates a link removal request to the target user to remove the network access link, and the source user switches from the forwarding mode to the direct mode to the target user.

[0009] The present invention adopts autonomous switching of direct-through and relay modes on the mobile side to communicate. Initially, the shortwave station on the fixed side is used as a relay station wireless network, and the source user and the target user directly establish a link. When the channel condition is good, the source user and the target user successfully establish a link and carry out communication services. At this time, the source user and the target user have high communication efficiency and good communication efficiency; when the channel condition is poor, the source user and the target user fail to establish a link, and the source user autonomously switches the mode from the direct-through mode to the relay mode to ensure that the source user and the target user can communicate normally; when the communication service ends or is in an idle state, the source user will autonomously send a link removal request to remove the network access link, reduce resource occupation, and enable other users to use the channel for communication.

[0010] In order to achieve fast link establishment, step S200 is specifically that the source user calls the target user in direct mode, selects the communication frequency with the highest signal-to-noise ratio, and forms a communication channel. Directly selecting the communication frequency with the highest signal-to-noise ratio to establish a link, when the channel condition is good, the link establishment can be completed quickly with minimal interference, improving the communication quality and efficiency; when the channel condition is poor, the link establishment fails, and the channel condition deviation can be quickly known, without trying other frequencies to establish a link. The source user directly switches to the forwarding mode to reduce the delay time of communication.

[0011] Both the source user and the target user are shortwave mobile users, located on the mobile side; multiple shortwave stations are located on the fixed side to ensure the communication of shortwave mobile users.

[0012] The process for a shortwave mobile user to join the wireless network of a relay station includes the following steps: Step 1: The shortwave mobile user sends the same uplink access request signal to multiple shortwave stations; Step 2: After receiving the uplink access request signal of the shortwave mobile user, the shortwave station simultaneously sends independent downlink access response signals to the shortwave mobile user; Step 3: After receiving different downlink access response signals, the shortwave mobile user sends the same uplink confirmation signal to the shortwave station, and the shortwave mobile user completes frequency selection and access to the wireless network of the relay station.

[0013] The shortwave station system is generally composed of separate receiving and transmitting devices, among which the receiving device generally adopts a shortwave broadband receiver. One device can receive multiple signals in parallel to meet the needs of group reception, while the transmitting device generally adopts a single-channel transmitter. One device can only transmit one signal at a time. By calling multiple transmitters of the shortwave station at the same time, the needs of group transmission and group transfer can be met. Therefore, if multiple mobile users access at the same time, the upper limit of the service capacity provided by the shortwave station is subject to the number of transmission channels of the shortwave station. When the number of concurrently accessing users at the same time exceeds the number of transmission channels of the shortwave station, the shortwave signal processing equipment in the shortwave station will refuse to respond to more access requests due to service overload to meet the parallel access requests of multiple users. The process of the shortwave station receiving and sending signals is specifically as follows: the shortwave station receives the uplink signal sent by the shortwave mobile user through the shortwave broadband receiver, and forwards it to the shortwave signal processing equipment of the shortwave station for signal demodulation. After the shortwave signal processing equipment recognizes the access request signaling of the shortwave mobile user, it generates a downlink access response signaling and performs signal modulation, and then sends it to the shortwave transmitter of the shortwave station for signal transmission.

[0014] The shortwave mobile user first sends an identical uplink access request signal to multiple shortwave stations on the fixed side. The uplink access request signal contains the user's identity, the network information requested to join, and the necessary encryption or verification information to ensure the integrity and security of the signal and increase the possibility of the user successfully joining the network; each shortwave station that receives the uplink access request signal will independently send a downlink access response signal to the shortwave mobile user after verifying the validity of the signal. These response signals are independent of each other and contain the identification information of each station, the available communication resources, and the authentication or authorization information. These response signals provide multiple options for the shortwave mobile user. The shortwave mobile user will send an uplink confirmation signal to all shortwave stations. After receiving the uplink confirmation signal, the shortwave station will confirm the shortwave mobile user's access request and allocate the corresponding network resources to it, thereby completing the process of the shortwave mobile user joining the wireless network of the relay station.

[0015] In order to avoid co-channel interference, the downlink access response signal is generated based on the uplink access request signal sent by the shortwave mobile user and the fixed frequency planning algorithm corresponding to each shortwave station:

[0016] The frequency of the uplink access request signal sent by shortwave mobile user 1, The frequency of the downlink reply signal sent by the shortwave station. The shortwave stations are planned. Since the planning of each shortwave station is different, the generated downlink access response signal The frequency of the mobile shortwave user is different from each other, which avoids the interference caused by multiple shortwave stations transmitting at the same frequency at the same time. Because of broadband reception, mobile shortwave users can receive at multiple downlink frequencies at the same time, and then perform diversity combining processing to improve the overall reception effect on the mobile side. For example, three shortwave stations are respectively / / The downlink response signal is sent on three frequencies, and the mobile user performs concurrent reception processing. The diversity type adopted by the present invention is frequency diversity, that is, multiple shortwave stations send broadcast signals on different frequencies at the same time, and the shortwave mobile user receives and combines them at the same time on different frequencies.

[0017] In order to improve communication efficiency and enhance communication security, the forwarding wake-up request instruction of step S400 includes the target user address, source user address, source user sending channel, and source user receiving channel data packets. By specifying the target user address, source user address, source user sending channel, and source user receiving channel data packets, redundant information and potential conflicts in the communication process are reduced, and communication efficiency is improved; by recording the source user address and identity verification, the security of the communication process is enhanced to prevent unauthorized access and potential security threats.

[0018] In order to improve communication efficiency and enhance communication security, the forwarding wake-up response instruction of step S600 includes the target user address, source user address, target user sending channel, and target user receiving channel data packets. By specifying the target user address, source user address, target user sending channel, and target user receiving channel data packets, redundant information and potential conflicts in the communication process are reduced, and communication efficiency is improved; by recording the target user address and identity verification, the security of the communication process is enhanced to prevent unauthorized access and potential security threats.

[0019] Shortwave stations use a wide-band receiving mode for wide-area hierarchical reception and process different signals in parallel. Since the shortwave stations participating in wide-area signal diversity reception are widely distributed in space, the effects of the long shortwave wavelength and the similar ionosphere characteristics of the adjacent areas are eliminated, thus improving the stability of communication.

[0020] The shortwave mobile user receiving end adopts wideband receiving and diversity combining mode, and combines multiple independent and unrelated or small-correlated fading signals. By combining multiple unrelated or small-correlated fading signals, the influence of fading is reduced, and the diversity reception, demodulation and combining processing of multiple signals are realized.

[0021] The shortwave mobile user receiving end combines multiple signals by, according to the demodulation quality of a single signal, using selective combining, equal gain combining and maximum ratio combining to receive data, thereby improving the success rate of shortwave communication services.

[0022] Compared with the prior art, the present invention has the following beneficial effects: 1. Improve the success rate and efficiency of communication services A direct link is first established between the source user and the target user to enhance the user experience. The mode is switched autonomously in parallel with the relay mode, with low requirements on the channel link quality. The source user, the target user and the corresponding relay site can access the network even when the channel quality is poor, thus resolving the difficulties and conflicts in link establishment. The channel can be released after the communication is completed, and the channel occupancy is low, thereby improving the success rate of communication services and communication efficiency.

[0023] 2. Reduce the impact of equipment failure The fixed-side signal relay stations of the present invention are not connected via a wired network, and the stations are relatively independent. When the wired network facilities fail or are damaged, the signal relay stations are not affected and can still communicate normally.

[0024] 3. Improve communication efficiency There is no unified convergence business processing center on the fixed side. After receiving the data packet, each relay station sends it to the target user wirelessly, effectively improving communication efficiency.

[0025] 4. Optimize large-scale networking mode The signal relay station and mobile users of the present invention can ensure that mobile users in a relatively large area can perform signal relay services through wide area reception, diversity combining and processing, thereby optimizing and improving the large-scale networking mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings of the present invention are only used for illustrative purposes and cannot be understood as limiting the present invention. In order to more clearly illustrate the technical methods of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 It is a schematic diagram of the organizational structure of the present invention.

[0028] Figure 2 It is a business process diagram of the present invention.

[0029] Figure 3 The present invention is a schematic diagram of the process of automatically accessing a shortwave mobile user's point-to-point wireless network without support.

[0030] Figure 4 It is a schematic diagram of frequency allocation for network frequency selection without relying on a point in the present invention.

[0031] Figure 5 The present invention is a schematic diagram of wide area access for point-to-network frequency selection between multiple shortwave mobile users and multiple shortwave stations. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical methods in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0033] Example 1 like Figure 1 As shown, the present embodiment provides a shortwave communication networking method with autonomous selection of communication mode, including a fixed side and a mobile side. The fixed side is composed of multiple shortwave stations. The shortwave stations improve the communication infrastructure and can realize wireless interconnection on pre-planned shortwave wireless channels, and can realize the transmission of services and signaling, and provide communication services for shortwave mobile users on the mobile side; the mobile side is composed of shortwave mobile users, and the shortwave mobile users adopt direct mode and forwarding mode, and switch autonomously according to the channel environment to improve the business communication rate. Except for the wired interconnection between the communication equipment inside a single shortwave station, there is no wired connection between the shortwave station and the shortwave mobile, and between each shortwave station.

[0034] In this embodiment, if Figure 2 As shown, a shortwave communication networking method for autonomously selecting a communication mode comprises the following steps: Step S100: shortwave mobile user 1 (source user) and shortwave mobile user 2 (target user) form a service communication object, set to direct mode, shortwave station A, shortwave station B and shortwave station C constitute a relay station wireless network to protect shortwave mobile users; Step S200, shortwave mobile user 1 (source user) calls shortwave mobile user 2 (target user) in direct mode, selects the communication frequency with the highest signal-to-noise ratio, and forms the best communication channel; Step S300: If the optimal communication channel meets the minimum signal-to-noise ratio condition for link establishment and the frequency selection and link establishment are successful, the subsequent communication service is directly executed; if the minimum signal-to-noise ratio condition for link establishment is not met and the frequency selection and link establishment fails, the shortwave mobile user 1 (source user) triggers the autonomous mode switching, that is, autonomously switches from the direct mode to the forwarding mode; Step S400: shortwave mobile user 1 (source user) automatically joins the relay station network within the working frequency band, and then sends a relay wake-up request instruction containing shortwave mobile user 2 (target user) to shortwave station A, shortwave station B, and shortwave station C.

[0035] Step S500: shortwave station A, shortwave station B and shortwave station C in the signal relay network receive a signal relay wake-up request instruction from shortwave mobile user 1 (source user), the shortwave station wakes up and calls shortwave mobile user 2 (target user), shortwave mobile user 2 (target user) receives the wake-up request instruction, switches the direct mode to the signal relay mode, and automatically joins the signal relay station network within the working frequency band; Step S600: shortwave mobile user 2 (target user) joins the relay station network and sends a relay response to shortwave mobile user 1 (source user) through the relay station. If the relay mode is successfully prepared, subsequent communication services are performed. Step S700: After completing the communication service, or in the service idle state, shortwave mobile user 1 (source user) initiates a link removal request to shortwave mobile user 2 (target user), then the network access link is removed, and shortwave mobile user 1 (source user) autonomously switches from the forwarding mode to the direct mode to the shortwave mobile user 2 (target user).

[0036] The shortwave mobile users on the mobile side use the autonomous switching between direct and relay modes to communicate, so that the shortwave mobile users can communicate normally in a variety of channel environments. Initially, the shortwave station on the fixed side is used as a relay station wireless network, and the source user and the target user directly establish a link. When the channel conditions are good, the source user and the target user successfully establish a link and carry out communication services. At this time, the source user and the target user have high communication efficiency and good communication efficiency; when the channel conditions are poor, the source user and the target user fail to establish a link, and the source user autonomously switches the mode from the direct mode to the relay mode to ensure that the source user and the target user can communicate normally; when the communication service ends or is in an idle state, the source user will autonomously send a disconnection request to dismantle the network link, reduce resource occupation, and enable other users to use the channel for communication.

[0037] The wake-up request instruction sent by shortwave mobile user 1 (source user) includes: target user address, source user address, source user sending channel, source user receiving channel data packet; the forwarding wake-up response instruction sent by shortwave mobile user 2 (target user) also includes target user address, source user address, target user sending channel, target user receiving channel data packet, which is convenient for shortwave stations to effectively identify guaranteed users and non-guaranteed users. By specifying the target user or source user address, source user or target user address, source user or target user sending channel and source user or target user receiving channel data packet, redundant information and potential conflicts in the communication process are reduced, and communication efficiency is improved; by recording the source user or target user address and identity authentication, the security of the communication process is enhanced to prevent unauthorized access and potential security threats.

[0038] In this embodiment, combined with Figure 3-4As shown in the figure, the specific steps for shortwave mobile users to automatically access the network without relying on point-to-network wireless network access, that is, shortwave mobile user 1 (source user) and shortwave mobile user 2 (target user) to join the relay station network within the working frequency band are: Step 1: 101, 102, and 103 processes are the same uplink access request signal initiated by the shortwave mobile user; Step 2: The processes 201, 202, and 203 are responses of the three shortwave stations to the uplink access request of the shortwave mobile user, i.e., independent downlink access response signals initiated to the shortwave mobile user almost simultaneously; Step 3: The processes 301, 302, and 303 are the same uplink confirmation signal initiated by the shortwave mobile user.

[0039] After three two-way interactions, the shortwave mobile user realized the frequency selection and wireless network access in three independent shortwave stations. Among them, the uplink access request signal contains the user's identity, the network information requested to join, and the necessary encryption or verification information to ensure the integrity and security of the signal and increase the possibility of the user successfully joining the network; after receiving the uplink access request signal, each shortwave station will verify the validity of the signal. When the signal is valid, each shortwave station will send a downlink access response signal to the shortwave mobile user. These response signals are independent of each other and contain the identification information of each station, the available communication resources, and the authentication or authorization information. These response signals provide multiple options for shortwave mobile users, from which shortwave mobile users can make the best choice; after receiving multiple downlink access response signals, the shortwave mobile user will select the best shortwave station and the communication frequency it provides according to the signal strength, quality, station resource status and other conditions, and send an uplink confirmation signal to the selected shortwave station. After receiving the uplink confirmation signal, the shortwave station will confirm the access request of the shortwave mobile user and allocate corresponding network resources to it, thus completing the process of the shortwave mobile user joining the wireless network of the relay station.

[0040] The shortwave station system is generally composed of separate receiving and transmitting devices, among which the receiving device generally adopts a shortwave broadband receiver. One device can receive multiple signals in parallel to meet the needs of group reception, while the transmitting device generally adopts a single-channel transmitter. One device can only transmit one signal at a time. By calling multiple transmitters of the shortwave station at the same time, the needs of group transmission and group transfer can be met. Therefore, if multiple mobile users access at the same time, the upper limit of the service capacity provided by the shortwave station is subject to the number of transmission channels of the shortwave station. When the number of concurrently accessing users at the same time exceeds the number of transmission channels of the shortwave station, the shortwave signal processing equipment in the shortwave station will refuse to respond to more access requests due to service overload to meet the parallel access requests of multiple users.

[0041] Shortwave mobile users on the uplink frequency The uplink signal of the first and third steps of the network access process is initiated on the uplink frequency. Multiple independent shortwave stations are respectively on the downlink frequency The downlink signal of the second step of the network access process is initiated. It is based on the uplink frequency of shortwave mobile users and the downlink frequency generated by the fixed frequency planning algorithm,

[0042] The frequency of the uplink access request signal sent by shortwave mobile user 1, The frequency of the downlink reply signal sent by the shortwave station. The shortwave stations are responsible for planning. Since the planning of each shortwave station is different, the downlink frequency generated by each shortwave station is different. Different from each other, it avoids the co-frequency interference caused by multiple shortwave stations transmitting at the same frequency at the same time. The shortwave station that receives the uplink signal of the shortwave mobile user sends a downlink response signal on the pre-planned downlink frequency. The shortwave mobile user receives the downlink signals simultaneously transmitted by the shortwave station on multiple downlink frequencies in parallel diversity, and improves the overall reception effect on the mobile side through diversity merging processing. The diversity type is frequency diversity, that is, multiple shortwave stations send broadcast signals at different frequencies at the same time, and the shortwave mobile user receives them at different frequencies in diversity and merges them. In addition, if the first or second step of the wireless network access fails, that is, all shortwave stations do not receive the uplink signal of the shortwave mobile user, or the shortwave mobile user does not receive the downlink signal of any station, it will trigger the shortwave mobile user to change to the next frequency Fu2, and repeat the point-to-network frequency selection process until the frequency selection succeeds or fails to exit.

[0043] In this embodiment, if Figure 5 As shown in the figure, when the shortwave mobile user 1 (source user) and the shortwave mobile user 2 (target user) are far away and cannot communicate directly, the shortwave mobile user and the shortwave station can be used to perform point-to-network frequency selection for wide area access, for example: Shortwave mobile user 1 (source user) successfully accesses shortwave station A, shortwave station B and shortwave station C through point-to-network frequency selection, and shortwave mobile user 2 (target user) successfully accesses shortwave station C, shortwave station D and shortwave station E through point-to-network frequency selection, wherein shortwave station C stores access information of shortwave mobile user 1 (source user) and shortwave mobile user 2 (target user) at the same time. At this time, shortwave mobile user 1 and shortwave mobile user 2 cannot directly communicate wirelessly due to the long distance (process 401), but can communicate business through the publicly accessed shortwave station C (processes 501, 502).

[0044] In this embodiment, the shortwave station on the fixed side adopts a broadband reception mode to achieve wide-area diversity reception and has parallel processing capabilities. Since the shortwave stations participating in the wide-area signal diversity reception are widely distributed in space, the influence of the long shortwave wavelength and the close ionospheric characteristics of the adjacent area are eliminated, and the stability of communication is improved. The target receiving end of the shortwave mobile user on the mobile side adopts a broadband reception and diversity combining mode. The target receiving end combines multiple independent, unrelated or very correlated fading signals to reduce the influence of fading, and realizes multi-channel signal diversity reception, demodulation, and combining processing. According to the demodulation quality of a single signal, selective combining, equal gain combining, and maximum ratio combining are used to successfully receive data. In addition, multiple diversity can be expanded, and the number of relay stations is not limited to 3. One or more relay stations can realize the relay function. The increase in the number of relay stations is conducive to improving the success rate of shortwave communication services through diversity combining. The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A shortwave communication networking method with autonomous selection of communication mode, characterized in that: The following steps are involved: Step S100: The shortwave stations form a relay station wireless network, and the source user and the target user are set to direct mode; Step S200: The source user calls the target user in direct mode to establish a communication channel; Step S300: Determine whether the communication channel meets the minimum signal-to-noise ratio condition for link establishment. If so, the frequency selection and link establishment are successful, and subsequent communication services are performed; if not, the frequency selection and link establishment fails, and the source user switches the mode from the direct mode to the forwarding mode; Step S400: The source user joins the wireless network of the relay station within the working frequency band and sends a relay wake-up request instruction to multiple shortwave stations; Step S500: After receiving the signal forwarding wake-up request instruction, multiple shortwave stations send different frequency wake-up request instructions to the target user. The target user processes the wake-up request instructions in a diversity manner, switches the direct mode to the signal forwarding mode, and joins the signal forwarding station wireless network within the working frequency band. Step S600: The target user sends a forwarding wake-up response instruction to the source user through the shortwave station, and the forwarding mode is successfully prepared to execute subsequent communication services; Step S700: After completing the communication service, or in the service idle state, the source user initiates a link removal request to the target user to remove the network access link, and the source user switches from the forwarding mode to the direct mode to the target user.

2. The shortwave communication networking method with autonomous selection of communication mode according to claim 1 is characterized in that: Specifically, step S200 includes: the source user calls the target user in direct mode, and selects a communication frequency with the highest signal-to-noise ratio to form a communication channel.

3. The shortwave communication networking method with autonomous selection of communication mode according to claim 2 is characterized in that: The source user and the target user are both shortwave mobile users, located at the mobile side; a plurality of shortwave stations are located at the fixed side, for ensuring the communication of the shortwave mobile users.

4. The shortwave communication networking method with autonomous selection of communication mode according to claim 3 is characterized in that: The process of the shortwave mobile user joining the wireless network of the relay station includes the following steps: Step 1: The shortwave mobile user sends the same uplink access request signal to multiple shortwave stations; Step 2: After receiving the uplink access request signal of the shortwave mobile user, the shortwave station simultaneously sends independent downlink access response signals to the shortwave mobile user; Step 3: After receiving different downlink access response signals, the shortwave mobile user sends the same uplink confirmation signal to the shortwave station, and the shortwave mobile user completes frequency selection and access to the wireless network of the relay station.

5. The shortwave communication networking method with autonomous selection of communication mode according to claim 4 is characterized in that: The downlink access response signal is generated according to the uplink access request signal sent by the shortwave mobile user and the fixed frequency planning algorithm corresponding to each shortwave station: The frequency of the uplink access request signal sent by shortwave mobile user 1, The frequency of the downlink reply signal sent by the shortwave station. Planning is done by shortwave stations.

6. The shortwave communication networking method with autonomous selection of communication mode according to claim 5 is characterized in that: The forwarding wake-up request instruction of step S400 includes a target user address, a source user address, a source user sending channel, and a source user receiving channel data packet.

7. The shortwave communication networking method with autonomous selection of communication mode according to claim 6 is characterized in that: The forwarding wake-up response instruction of step S600 includes the target user address, the source user address, the target user sending channel, and the target user receiving channel data packet.

8. The shortwave communication networking method with autonomous selection of communication mode according to claim 7 is characterized in that: The shortwave station adopts a broadband receiving mode to perform wide-area hierarchical reception and process different signals in parallel.

9. A shortwave communication networking method for autonomously selecting a communication mode according to claim 8, characterized in that: The shortwave mobile user receiving end adopts a wideband receiving and diversity combining mode. The receiving end adopts a maximum ratio combining algorithm to combine multiple independent, unrelated or small-correlated fading signals, and weights the signal-to-noise ratio of each branch signal. The weight is proportional to the signal-to-noise ratio of the branch. The weighted coefficients of the branch signals are combined to output the combined signal.

10. The shortwave communication networking method with autonomous communication mode selection according to claim 9 is characterized in that: The shortwave mobile user receiving terminal combines multiple signals specifically by receiving data in the manner of selective combining, equal gain combining and maximum ratio combining according to the demodulation quality of a single signal.

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