Emergency communication system and communication method

Abstract

The invention discloses an emergency communication system and a communication method, and belongs to the technical field of communication. The emergency communication system comprises a plurality of mobile base stations which are in signal connection to form a base communication network; the plurality of terminal devices are arranged, and the terminal devices are in signal connection with the mobile base station; each terminal device completes information interaction through a base layer communication network constructed by the mobile base station; the terminal equipment comprises a main communication module used for accessing a base layer communication network; and the signal quality detection module is used for detecting the signal strength of each mobile base station. According to the technical scheme provided by the invention, the mobile terminal can be ensured to have good communication quality in a base communication network signal coverage range.

Description

Technical Field

[0001] The present application belongs to the field of communication technology, and in particular, relates to an emergency communication system and a communication method. Background Art

[0002] During railway construction, workers often rely on self-built communication systems to keep in touch, as the work sites are often located in the wild. However, in the face of sudden geological disasters such as landslides and mudslides, the original communication system may be damaged by the disaster. Therefore, it is particularly important to build a temporary construction emergency communication system inside the construction site. This type of temporary emergency communication system is mainly composed of mobile base stations and several terminal devices. The communication information between terminal devices is first transmitted to the base station, and then forwarded to the target device by the base station.

[0003] In emergency situations, frequency band division is usually used for communication. Specifically, the information sent by the user in a specific communication frequency band will be broadcast by the mobile base station in the frequency band. If another terminal device receives the information in this frequency band, communication between the two can be achieved.

[0004] However, this solution is limited by the performance of mobile base stations in practical applications. Since the radiation range of mobile base stations is relatively limited, multiple base stations need to be deployed in the site and networked through these base stations to build a communication network. When all terminal devices are within the coverage of the corresponding base station, the communication quality can be ensured. However, once the terminal devices move frequently between different base stations, they may encounter poor communication quality because they cannot directly establish communication with other base stations. Summary of the invention

[0005] The purpose of this application is to overcome the problems of the prior art and disclose an emergency communication system and a communication method. Through the technical solution of this application, it is ensured that the mobile terminal has good communication quality within the signal coverage of the grassroots communication network.

[0006] On the one hand, the purpose of this application is achieved through the following technical solutions:

[0007] An emergency communication system, comprising:

[0008] A plurality of mobile base stations are provided, and signals between the mobile base stations are connected to form a basic communication network;

[0009] A terminal device, a plurality of which are provided, and the terminal device is connected to a mobile base station signal;

[0010] Each terminal device completes information exchange through the grassroots communication network built by mobile base stations;

[0011] The terminal equipment includes:

[0012] A main communication module, used to access the grassroots communication network;

[0013] A signal quality detection module is used to detect the signal strength with each mobile base station;

[0014] The terminal control module is signal-connected to the main communication module and the signal quality detection module respectively. The terminal control module obtains in real time the quality of the communication channel between the main communication module and the connected mobile base station, as well as the quality of the remaining communication channels with the mobile base stations; when the quality of the communication channel between the main communication module and the connected mobile base station is less than the quality of the remaining communication channels with the mobile base stations, the terminal control module controls the main communication module to switch to the mobile base station with the highest communication channel quality among the remaining mobile base stations to establish a communication connection.

[0015] In this application, a basic communication network is first established using a mobile base station, and the function of the terminal device to connect to the signal through the network is realized. Considering the communication quality problems that may be caused by the staff carrying the terminal device, this solution adopts the strategy of continuously monitoring the signal strength of other mobile base stations. When the communication channel quality of the main communication module decreases, the system can quickly switch to a mobile base station with better signal, thereby ensuring that the mobile terminal always maintains a high-quality communication state within the coverage area of ​​the basic communication network.

[0016] In a temporary grassroots communication network, there may be a large number of clustered terminal devices in a certain area, so the mobile base station in the area needs to communicate with multiple terminal devices, which will lead to communication congestion. To address this problem, this application provides the following technical solutions:

[0017] According to a preferred embodiment, the mobile base station comprises:

[0018] Base station communication module, used for signal connection with other mobile base stations;

[0019] There are multiple frequency band communication modules, each of which corresponds to a communication frequency band, and the terminal device is connected to the frequency band communication module by signal;

[0020] A buffer, all frequency band communication modules and base station communication modules are connected to the buffer signal;

[0021] A base station control module, connected to the buffer signal;

[0022] Wherein, the base station control module controls the buffer to receive the uploaded information uploaded by the communication modules of different frequency bands, and distributes the uploaded information to the corresponding mobile base station through the base station communication module;

[0023] The base station control module controls the buffer to receive downlink information sent by different mobile base stations, and sends the downlink information to the corresponding terminal equipment using different frequency band communication modules.

[0024] In the technical solution provided in the present application, a buffer and multiple frequency band communication modules are provided, so that information congestion can be avoided when the base station receives the communication module, thereby improving communication efficiency.

[0025] According to a preferred implementation, the frequency band communication module plays the downlink information by broadcasting.

[0026] In the solution provided in the present application, the frequency band communication module plays the downlink information in a broadcasting manner, so all terminal devices located in the basic mobile network can receive the downlink information, so that grouping can be performed by the communication frequency band.

[0027] In emergencies, emergency equipment resources are limited, and the range of staff activities often deviates from the expected range. As a result, staff may carry terminal equipment to the edge of the mobile base station signal coverage area, which will lead to poor communication between the mobile terminal and the grassroots communication network.

[0028] According to a preferred embodiment, the mobile base station further includes a location information acquisition module, which is used to acquire the location of the terminal device connected to each frequency band communication module;

[0029] The base station control module adjusts the signal coverage of the frequency band communication module based on the location of each terminal device.

[0030] In the technical solution provided in the present application, the characteristic that staff members tend to gather at the edge is utilized to collect the location of each terminal device, and the signal coverage range of the frequency band communication module is adjusted according to the location of each terminal device. In this way, when there is a certain offset between the location of the staff members' activities and their locations, there is no need to reinstall or adjust the location of the mobile base station. Only the signal coverage area of ​​the mobile base station needs to be changed to increase the communication quality between the mobile terminal and the grassroots communication network.

[0031] In an emergency environment, it is difficult for the terminal device to accurately obtain its own location, so it is naturally unable to feedback its accurate location information to the mobile base station. In addition, the distance is not the only factor that affects the signal strength. Because of the obstruction of obstacles, some locations closer to the mobile base station will be more interfered. Therefore, it is necessary for the mobile base station to spend more resources to receive signals in such areas. Based on this, the present application provides the following technical solutions:

[0032] According to a preferred embodiment, the information acquisition module includes:

[0033] A direction acquirer, used to acquire the direction of each terminal device relative to the mobile base station;

[0034] The information strength acquirer is used to acquire the signal strength coefficient sent by each terminal device to the frequency band communication module.

[0035] In the solution provided in the present application, the information acquisition module will synchronously acquire the direction of the terminal device and the signal strength sent by the terminal device. By using the direction of the terminal device compared to the mobile base station, the approximate direction of each terminal device can be determined, and the signal strength can be used to determine the interference between each terminal device and the frequency band communication module. In this way, the coverage range of the frequency band communication module can be reasonably adjusted.

[0036] According to a preferred implementation, the base station control module adjusts the main beam direction of the frequency band communication module to adjust the coverage range of the frequency band communication module.

[0037] According to a preferred embodiment, the signal strength coefficient α is positively correlated with the average signal-to-noise ratio of the terminal device.

[0038] When using the terminal device, it will introduce a lot of noise signals. If the signal-to-noise ratio is directly used to judge the signal strength, it cannot accurately reflect the current communication status. Based on this, the application provides the following technical solutions:

[0039] According to a preferred embodiment, the signal strength coefficient α is positively correlated with the high amplitude distribution ratio of the terminal device.

[0040] In the technical solution provided in the present application, total harmonic distortion is used to judge the communication status, so in practice it can reduce the impact of background noise near the terminal device on the signal strength coefficient, and thus accurately characterize the impact on the information during the transmission process.

[0041] On the other hand, the present application also discloses:

[0042] A communication method, using the aforementioned emergency communication system to build a communication network; comprising the following steps:

[0043] Step 1: Several mobile base stations are connected to form a basic communication network;

[0044] Step 2: The terminal device is connected to the grassroots communication network;

[0045] Step 3: The terminal control module obtains in real time the quality of the communication channel between the main communication module and the connected mobile base station, as well as the quality of the remaining communication channels with the mobile base stations; when the quality of the communication channel between the main communication module and the connected mobile base station is less than the quality of the remaining communication channels with the mobile base stations, the terminal control module controls the main communication module to switch to the mobile base station with the highest communication channel quality among the remaining mobile base stations to establish a communication connection.

[0046] This technical solution first uses a mobile base station to establish a basic communication network and realizes the function of terminal devices to connect signals through this network. Considering the communication quality problems that may be caused by the staff carrying terminal devices, this solution adopts the strategy of continuously monitoring the signal strength of other mobile base stations. When the communication channel quality of the main communication module decreases, the system can quickly switch to a mobile base station with better signal, thereby ensuring that the mobile terminal always maintains a high-quality communication state within the coverage area of ​​the basic communication network.

[0047] The aforementioned main scheme of the present application and its further options can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection in the present application. After understanding the scheme of the present application, those skilled in the art can understand that there are multiple combinations based on the prior art and common knowledge, all of which are technical schemes to be protected by the present application, and they are not exhaustively listed here. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The illustrative embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application.

[0049] In addition, throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and that the components and elements are not necessarily drawn to scale.

[0050] Figure 1 This is a structural diagram of the emergency communication system.

[0051] Figure 2 A schematic diagram of the structure of the terminal device.

[0052] Figure 3 A schematic diagram of the structure of a mobile base station.

[0053] Figure 4 Amplitude-time plot of a piece of information. DETAILED DESCRIPTION

[0054] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0055] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0056] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] In addition, the present application would like to point out that, in the present application, unless the specific structure, connection relationship, positional relationship, power source relationship, etc. are specifically written out, the structure, connection relationship, positional relationship, power source relationship, etc. involved in the present application are all known by those skilled in the art on the basis of the prior art without creative work.

[0058] Example 1

[0059] Reference Figure 1 The emergency communication system includes a mobile base station and several terminal devices. Among them, there are multiple mobile base stations. The signals between multiple mobile base stations are connected to form a grassroots communication network. The mobile base station is an information transceiver center, which can collect information and distribute signals. Each base station can radiate a certain range, so multiple mobile base stations can be combined together to merge the coverage range. In practice, each mobile base station is connected to at least one mobile base station signal, but it does not rule out the possibility that a mobile base station can be connected to multiple mobile base station signals. However, as long as the mobile base station is connected to at least one mobile base station signal, a larger grassroots communication network can be formed.

[0060] There are multiple terminal devices, and the terminal devices are connected to the mobile base station signals; each terminal device completes information exchange through the grassroots communication network constructed by the mobile base station. Specifically, the terminal device in this solution is a walkie-talkie. After the grassroots communication network is constructed, each staff member can use the walkie-talkie in his hand to send and receive voice. In the event of an emergency, the mobile base stations are arranged in different locations, and then a grassroots communication network that can cover a certain range is formed. Each staff member communicates with the handheld terminal device and calmly responds to emergencies.

[0061] refer to Figure 2More specifically, the terminal device includes a main communication module, a signal quality detection module, a terminal control module, and a voice transceiver module. The voice input by the staff's handheld terminal device is converted into digital information through the voice collection module, and the digital information transmitted from other terminal devices is converted into analog information (sound) through the voice transceiver module. The voice transceiver module is a combination of a microphone and a speaker.

[0062] The main communication module is used to access the grassroots communication network. Each mobile terminal uses the main communication module to connect to the corresponding mobile base station signal. The signal quality detection module is used to detect the signal strength with each mobile base station. When the mobile base station is working, it will radiate signals outward. The signal quality detection module will determine the signal strength of each mobile base station by receiving these signals. The terminal control module will automatically select the mobile base station with high signal strength based on the signal strength of each mobile base station received, and then guide the terminal device to connect to the mobile base station with high signal strength.

[0063] The signal quality detection module determines the signal strength of the mobile base station, which is a prior art, or is implemented using the solution of Example 2. The main communication module switches the signal connection with different mobile base stations, which is also a prior art. The specific switching method and the communication protocol between the mobile base station and the terminal device are no longer limited.

[0064] Embodiment 2: The difference between Embodiment 2 and Embodiment 1 is that the mobile base station can implement multi-channel communication to reduce communication congestion. Figure 3 :The mobile base station includes a base station communication module, a frequency band communication module, a buffer and a base station control module. Among them, the base station communication module is responsible for the communication between mobile base stations, and the mobile base stations are connected by signals through their respective base station communication modules to form a grassroots communication network.

[0065] There are multiple frequency band communication modules, and each frequency band communication module receives a different signal frequency band. The frequency band communication module is connected to the buffer signal. The base station control module is also connected to the buffer signal. Among them, each frequency band communication module is an independent module, each frequency band communication module can modulate the direction of the main beam, and the frequency band communication modules do not interfere with each other.

[0066] The buffer is connected to the signals of each frequency band communication module, and the uplink information of each terminal device received by all frequency band communication modules will be stored in the buffer. At the same time, the downlink information sent by each mobile base station to the current mobile base station will also be stored in the buffer. The base station control module controls the buffer to receive the upload information uploaded by different frequency band communication modules, and distributes the upload information to the corresponding mobile base station through the base station communication module; the base station control module controls the buffer to receive the downlink information sent by different mobile base stations, and sends the downlink information to the corresponding terminal device using different frequency band communication modules. The frequency band communication module sends the downlink information by broadcasting.

[0067] When distributing downlink information, the main thing is to determine the frequency band in which the terminal device that sends the downlink information sends the information. For example, if staff member A uses terminal device 1 to send a voice message to mobile base station No. 1 in the 433MHz frequency band, after the buffer of mobile base station No. 1 receives the uplink information, it will be sent to mobile base station No. 2 connected to it. For base station No. 2, this information is downlink information. After the downlink information is received by the base station communication module of mobile base station No. 2, it will be sent to the buffer of mobile base station No. 2, and then the base station control module of base station No. 2 will select the frequency band communication module of the 433MHz frequency band to broadcast the information. Therefore, if the terminal device within the range of base station No. 2 turns on the 433MHz frequency band, it can receive the information.

[0068] In practice, each mobile base station has the same number of frequency band communication modules. Each mobile terminal can receive the same number of frequency bands as the number of frequency band communication modules in a mobile base station. The frequency band communication module broadcasts downlink information by broadcasting. Therefore, after the staff sends a voice signal in a certain frequency band with the terminal device, the rest of the terminal devices within the entire grassroots communication network can receive the voice signal as long as the reception of the frequency band is turned on.

[0069] When discussing the adjustment of the coverage of mobile base stations, there are relief measures for the case where the terminal equipment moves to the edge of the grassroots communication network, that is, the mobile base station with the best signal quality among the mobile base stations received by the terminal equipment. There are also relief measures when quality problems exist. In this case, only the mobile base station and the terminal equipment within the coverage area need to be considered, without considering the other mobile base stations and terminal equipment in the system.

[0070] Furthermore, the frequency band communication module in this solution is an independent communication module, which is a conventional radio frequency communication device. The signal coverage can be adjusted by adjusting the direction of the main beam. In practice, it is to adjust the angle of the antenna. In this solution, the structure of the frequency band communication module and the specific main beam direction adjustment method are no longer limited.

[0071] The mobile base station also includes a location information acquisition module, which is used to acquire the location of the terminal device connected to each frequency band communication module; the base station control module adjusts the signal coverage of the frequency band communication module based on the location of each terminal device. Further, the information acquisition module includes: a direction acquirer, which is used to acquire the direction of each terminal device relative to the mobile base station; an information strength acquirer, which is used to acquire the signal strength coefficient sent by each terminal device to the frequency band communication module.

[0072] The direction acquirer is an antenna array composed of multiple antennas. During operation, the terminal device will periodically send electromagnetic wave signals of a specific frequency band to the direction acquirer. When the antenna array receives the electromagnetic wave signal, it will calculate the direction of the terminal device from the mobile base station based on the phase difference of the signals received by different antennas.

[0073] In this solution, the direction acquirer calculates the distance between each terminal device in the direction of each other, which is an existing technology. In fact, it is the same as the way radar detects the angle of the target object. The principle of radar is: electromagnetic waves are emitted into space. After hitting an object, the electromagnetic waves will be reflected back. For the reflected electromagnetic waves, the antenna array on the radar will calculate the direction of the object from the radar based on the phase difference. In this solution, the terminal device is directly allowed to send electromagnetic wave signals regularly, so compared with radar positioning, the reflected electromagnetic waves cannot represent the distance, but can represent the direction and angle. Of course, it should be noted that in order to increase accuracy, the electromagnetic wave signal returned by the terminal device needs to include the time information of sending the electromagnetic wave.

[0074] The above is the way in which the direction acquirer obtains the direction of each terminal device from the mobile base station.

[0075] The information strength acquirer is used to acquire the signal strength coefficient sent by each terminal device to the frequency band communication module. The information strength acquirer determines the communication status of each terminal device and the mobile base station based on the signal strength. If all the terminal devices in mobile base station No. 1 are distributed to the west of mobile base station No. 1, the main beam direction of mobile base station No. 1 is east, and the communication quality between all terminal devices and mobile base station No. 1 is low, then the main beam direction needs to be adjusted.

[0076] In this solution, since the communication modules of each frequency band are independent of each other, the communication modules of each frequency band are also independent of each other when adjusting the direction of the main beam.

[0077] Specifically, we take a frequency band communication module as an example: the base station control module obtains all the terminal devices currently connected to the frequency band communication module to obtain the terminal device set B (in practice, the terminal device adjusts the communication frequency band less frequently, and this scheme assumes that the terminal device will not adjust the frequency band for receiving and transmitting signals). The base station control module obtains all the information X stored in the buffer of these terminal devices in the last 5 minutes, and calculates the signal strength coefficient α sent by each terminal device to the frequency band communication module in the last 5 minutes based on the information X. 5 minutes in this scheme is a preset value. The base station control module obtains the direction of all terminal devices in the terminal device set B. In this way, the signal strength coefficient α is used to reflect the communication quality between the current terminal device and the frequency band communication module. If the communication quality is good, there is no need to adjust the main beam direction. If the communication quality is not good, it is necessary to adjust the main beam direction so that the main beam direction is biased toward the direction of the terminal device.

[0078] Thus, in this solution, the base station control module adjusts the main beam direction of the frequency band communication module according to the direction and communication quality of all terminal devices under each frequency band communication module, thereby increasing the communication quality between the terminal device and the base station control module.

[0079] This embodiment provides two methods to calculate the signal strength coefficient α. Specifically:

[0080] In some implementations: the signal strength coefficient α is positively correlated with the average signal-to-noise ratio of the terminal device.

[0081] Among them, P X,1 is the noise power of information X of the terminal device within a predetermined time, P X,2 is the signal power of information X of the terminal device within a predetermined time. In this scheme, the signal strength coefficient α is positively correlated with the signal-to-noise ratio. The larger the signal-to-noise ratio, the better the corresponding communication quality.

[0082] In other implementations, the signal strength coefficient α is positively correlated with the high amplitude distribution ratio of the terminal device. The greater the proportion of high amplitude, the better the corresponding communication quality. Figure 4 As shown, in a normal emergency environment, in addition to the voice of the staff communicating, there is also the noise of the construction site. Therefore, the signal transmitted by the terminal device to the mobile base station is information with a certain amplitude. If the terminal device is interfered in the process of transmitting information to the mobile base station, it is actually a process in which the phase of the signal moves and the amplitude of the highest signal decreases. The change in the phase of the signal will increase the difficulty of analysis, and the decrease in the amplitude of the highest signal will cause the signal to be submerged in the noise signal, making it impossible to accurately read the signal. For this reason, in this scheme, the amplitude ratio in the information sent by the terminal device to the mobile base station is used as a representation of the signal strength coefficient.

[0083] In this embodiment, the signal strength coefficient α is calculated as follows:

[0084] Step 1: Obtain all information X uploaded by the terminal devices in the buffer within 5 minutes, and concatenate all information X together to form combined information D;

[0085] Step 2: Calculate the mean u and standard deviation t of the amplitude of the combined information D, and calculate the Gaussian density distribution function of the combined information D;

[0086]

[0087] Step 3: Calculate the probability density function P of the combined information D in the amplitude interval [g, h] ((g，h) ; Where g is the preset lower limit of amplitude, and g is the preset upper limit of amplitude;

[0088]

[0089] Here, ∫ represents the integral symbol, and dx represents a small variable on x.

[0090] In this scheme, the probability density function P is calculated (g，h) The key is to determine the lower and upper limits of the amplitude. The determination of the lower and upper limits of the amplitude can be evaluated based on the upper and lower limits of 0 and 1 recognition when reading information X. Figure 4 As shown, Figure 4 The horizontal axis is time, and the vertical axis is amplitude. In signal processing, a series of 010101 data is actually converted into electromagnetic waves, and then sent to the receiver. After receiving the electromagnetic waves, the receiver will read the high amplitude of the electromagnetic waves as 1 and the low amplitude as 0. The noise is the messy waveform between the two read signals. When reading valid information, it is read according to the phase and amplitude to identify noise. Therefore, when designing the amplitude range in this scheme, it is set according to the amplitude reading range in the actual modulation.

[0091] Thus, according to the above scheme, the direction of the terminal device relative to the mobile base station and the communication quality of each terminal device can be obtained. Thus, the mobile base station can continuously adjust the direction of the main beam to keep the communication quality of each terminal device within a reasonable range. When the direction of the terminal device relative to the mobile base station and the communication quality of each terminal device are known, how to adjust the main beam direction is an existing technology and is limited by the radiation range of the main beam, which will not be further discussed here.

[0092] Example 3

[0093] Embodiment 3 provides a communication method based on Embodiment 1, using the aforementioned emergency communication system to construct a communication network; the communication method comprises the following steps:

[0094] Step 1: Several mobile base stations are connected to form a basic communication network;

[0095] Step 2: The terminal device is connected to the grassroots communication network;

[0096] Step 3: The terminal control module obtains in real time the quality of the communication channel between the main communication module and the connected mobile base station, as well as the quality of the remaining communication channels with the mobile base stations; when the quality of the communication channel between the main communication module and the connected mobile base station is less than the quality of the remaining communication channels with the mobile base stations, the terminal control module controls the main communication module to switch to the mobile base station with the highest communication channel quality among the remaining mobile base stations to establish a communication connection.

[0097] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An emergency communication system, characterized in that: include: A plurality of mobile base stations are provided, and signals between the mobile base stations are connected to form a basic communication network; A terminal device, a plurality of which are provided, and the terminal device is connected to a mobile base station signal; Each terminal device completes information exchange through the grassroots communication network built by mobile base stations; The terminal equipment includes: A main communication module, used to access the grassroots communication network; A signal quality detection module is used to detect the signal strength with each mobile base station; The terminal control module is signal-connected to the main communication module and the signal quality detection module respectively. The terminal control module obtains in real time the quality of the communication channel between the main communication module and the connected mobile base station, as well as the quality of the remaining communication channels with the mobile base stations; when the quality of the communication channel between the main communication module and the connected mobile base station is less than the quality of the remaining communication channels with the mobile base stations, the terminal control module controls the main communication module to switch to the mobile base station with the highest communication channel quality among the remaining mobile base stations to establish a communication connection.

2. The emergency communication system according to claim 1, characterized in that: The mobile base station includes: Base station communication module, used for signal connection with other mobile base stations; There are multiple frequency band communication modules, each of which corresponds to a communication frequency band, and the terminal device is connected to the frequency band communication module by signal; A buffer, all frequency band communication modules and base station communication modules are connected to the buffer signal; A base station control module, connected to the buffer signal; The base station control module controls the buffer to receive the uploaded information uploaded by the communication modules of different frequency bands, and distributes the uploaded information to the corresponding mobile base station through the base station communication module; The base station control module controls the buffer to receive downlink information sent by different mobile base stations, and sends the downlink information to the corresponding terminal equipment using different frequency band communication modules.

3. The emergency communication system according to claim 2, characterized in that: The frequency band communication module plays the downlink information by broadcasting.

4. The emergency communication system according to claim 3, characterized in that: The mobile base station also includes a location information acquisition module, which is used to obtain the location of the terminal device connected to each frequency band communication module; The base station control module adjusts the signal coverage of the frequency band communication module based on the location of each terminal device.

5. The emergency communication system according to claim 4, characterized in that: The information acquisition module includes: A direction acquirer, used to acquire the direction of each terminal device relative to the mobile base station; The information strength acquirer is used to acquire the signal strength coefficient sent by each terminal device to the frequency band communication module.

6. The emergency communication system according to claim 2, characterized in that: The base station control module adjusts the main beam direction of the frequency band communication module to adjust the coverage range of the frequency band communication module.

7. The emergency communication system according to claim 5, characterized in that: The signal strength coefficient α is positively correlated with the average signal-to-noise ratio of the terminal device.

8. The emergency communication system according to claim 5, characterized in that: The signal strength coefficient α is positively correlated with the high amplitude distribution ratio of the terminal equipment.

9. A communication method, using the emergency communication system according to any one of claims 1 to 8 to construct a communication network; characterized in that: The steps include: Step 1: Several mobile base stations are connected to form a basic communication network; Step 2: The terminal device is connected to the grassroots communication network; Step 3: The terminal control module obtains in real time the quality of the communication channel between the main communication module and the connected mobile base station, as well as the quality of the remaining communication channels with the mobile base stations; when the quality of the communication channel between the main communication module and the connected mobile base station is less than the quality of the remaining communication channels with the mobile base stations, the terminal control module controls the main communication module to switch to the mobile base station with the highest communication channel quality among the remaining mobile base stations to establish a communication connection.

Images