TDCS anti-interference communication system and communication method based on TDMA

Abstract

The embodiment of the invention provides a TDCS anti-interference communication system and method based on TDMA, and relates to the technical field of wireless communication, and the communication system comprises a comprehensive application layer, a data link layer, a physical layer and a perception decision module. The comprehensive application layer is connected with the data link layer, the data link layer is connected with the physical layer, and the perception decision module is respectively connected with the comprehensive application layer, the data link layer and the physical layer. According to the technical scheme provided by the invention, in combination with the characteristic that the communication parameters are flexibly adjusted according to the channel state by the TDCS, the communication and sensing time slots of the cognitive users in the network are coordinated by utilizing the thought of time division multiplexing (TDMA), the working state of the network is dynamically adjusted, and stable multi-user anti-interference communication in a complex radio frequency environment is realized.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to a TDMA-based TDCS anti-interference communication system and a communication method. Background Art

[0002] With the widespread use of wireless communication services in military and civilian fields, spectrum resources suitable for electromagnetic wave transmission are becoming increasingly precious under current communication technology conditions. Due to the openness of electromagnetic space, mutual interference between wireless communication devices is inevitable, making it difficult to implement communication services.

[0003] As jamming technologies evolve from traditional narrowband jamming to broadband and smart jamming, anti-jamming techniques such as spread spectrum, frequency hopping, and time hopping have been applied to anti-jamming communication systems. However, because these techniques lack the ability to proactively acquire information about the time-frequency distribution of interfering signals, their use can lead to a decrease in communication system performance. Cognitive radio technology, which aims to improve spectrum efficiency, is one approach to addressing this issue. Its core concept is to interact with the surrounding environment to perceive and utilize idle spectrum in physical space, thereby limiting the occurrence of communication conflicts.

[0004] Building on this foundation, transform domain communication systems (TDCS) leverage spectrum sensing and decision-making techniques within cognitive radio to proactively identify the frequency range of interfering signals, identify idle spectrum, and avoid interfered frequency bands by jointly designing signal waveforms at both the transmitter and receiver ends. This system demonstrates significant potential for development. However, due to the flexible and changeable signal waveforms and the need for frequent spectrum sensing, the lack of a compatible multi-user networking protocol has limited its application. Summary of the Invention

[0005] The embodiments of the present application provide a TDMA-based TDCS anti-interference communication system and a communication method to solve the technical problem in the prior art that the TDCS system is limited in use in multi-user networking.

[0006] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0007] According to a first aspect of an embodiment of the present application, a TDMA-based TDCS anti-interference communication system is provided, which is applied to network communication between a TDCS transmitter and a receiver with spectrum sensing and spectrum decision capabilities, including:

[0008] Integrated application layer, data link layer, physical layer and perception decision module;

[0009] The integrated application layer is connected to the data link layer, the data link layer is connected to the physical layer, and the perception decision module is connected to the integrated application layer, the data link layer and the physical layer respectively;

[0010] In the data transmission process, the integrated application layer is used to package the message data into application layer frames and transmit them to the data link layer; the data link layer is used to assemble the application layer frames into physical layer service data units and transmit them to the physical layer; the physical layer is used to generate a transmission signal from the physical layer service data units for transmission;

[0011] In the data receiving process, the physical layer is used to demodulate the received data to obtain the physical layer service data unit and transmit it to the data link layer; the data link layer is used to determine whether the receiving address of the received data is correct. If correct, it is transmitted to the integrated application layer; the integrated application layer is used to verify whether the data is correct and store the correct data;

[0012] The perception decision module is used to collect the user's communication status from the integrated application layer, the data link layer and the physical layer during the data sending process and the data receiving process to make network behavior decisions, and pass the decision parameters to the integrated application layer, the data link layer and the physical layer.

[0013] In some embodiments of the present application, based on the aforementioned solution, the communication system allocates time slots to users in the network through beacon frames.

[0014] In some embodiments of the present application, based on the aforementioned solution, the physical layer is provided with four modulation modes: CCSK, BPSK, QPSK and 16QAM.

[0015] In some embodiments of the present application, based on the aforementioned scheme, the application layer frame includes a frame sequence number field, a frame ACK number field, an error control field, a data type field and a data length field.

[0016] In some embodiments of the present application, based on the aforementioned solution, the physical layer service data unit includes: a frame control field, a duration field, an address field, a frame sequence number field, a data field, and an error detection field.

[0017] In some embodiments of the present application, based on the aforementioned solution, the physical layer adds a preamble training sequence and a header for synchronization before modulating the physical layer service data unit.

[0018] According to a second aspect of an embodiment of the present application, a communication method based on the overnight system according to the first aspect is provided, comprising:

[0019] During the communication process, the physical layer obtains spectrum sensing data and transmits it to the sensing decision module, which performs modulation control and channel control on the physical layer based on the spectrum sensing data.

[0020] During the communication process, the data link layer obtains the beacon reception status and transmits it to the perception decision module, and the perception decision module controls the beacon sending of the data link layer based on the beacon reception status;

[0021] During the communication process, the integrated application layer obtains the communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data.

[0022] In some embodiments of the present application, based on the aforementioned solution, the physical layer obtains spectrum sensing data and transmits it to the sensing decision module, and the sensing decision module performs modulation control and channel control on the physical layer based on the spectrum sensing data, including:

[0023] The physical layer determines whether the primary user signal is received based on the data's prior information. If the primary user signal is recognized, the physical layer reports the primary user identifier to the perception decision module, which then switches channels.

[0024] If the main user signal is not identified, it is determined whether there are other interference signals on the current working channel based on the power spectrum amplitude. If interference exists, the interference identifier is reported to the perception decision module. The perception decision module controls the physical layer to gradually reduce the modulation order. If no interference exists, the perception decision module controls the physical layer to gradually increase the modulation order.

[0025] In some embodiments of the present application, based on the aforementioned solution, the data link layer obtains beacon reception status and transmits it to the perception decision module. The perception decision module controls the data link layer to send beacons based on the beacon reception status, including:

[0026] If the data link layer fails to receive a beacon frame within the set time, it reports the beacon loss indicator to the perception decision module;

[0027] After the perception decision module detects that the beacon has lost the identifier, it controls the communication system to switch channels.

[0028] In some embodiments of the present application, based on the aforementioned solution, the integrated application layer obtains communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data, including:

[0029] The integrated application layer continuously calculates the signal reception success rate within a set time period based on the received confirmation number and error checking;

[0030] If the signal reception success rate within the set time period is lower than the set threshold, a low communication success rate flag is reported to the perception decision module;

[0031] After the perception decision module detects the low communication success rate indicator, it controls the network to switch the working channel.

[0032] The technical solution of the present application rationally designs a TDMA-based multi-user TDCS communication system according to the technical characteristics of the TDCS communication system, thereby overcoming the shortcoming that the TDCS system cannot form a multi-user network for communication.

[0033] The technical solution of the present application utilizes TDMA technology and uses beacon frames to complete the tasks of allocating time slots to multiple users and switching channels, thereby maintaining smooth operation of the network in the case of multi-user, multi-channel communications.

[0034] The technical solution of this application can make comprehensive decisions based on the TDCS spectrum perception results and information such as the current operating parameters of the network, and flexibly adjust the network operating status according to the real-time communication conditions, thereby improving communication efficiency, reducing energy consumption and optimizing resource allocation, thereby ensuring efficient and stable communication transmission, and significantly improving the adaptive ability of the communication system in complex environments.

[0035] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings are incorporated into and constitute a part of the specification, illustrating embodiments consistent with the present application and, together with the specification, explaining the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0037] Figure 1 FIG2 shows a schematic structural diagram of a TDMA-based TDCS anti-interference communication system according to an embodiment of the present application;

[0038] Figure 2 A schematic diagram of network time slot allocation according to an embodiment of the present application is shown;

[0039] Figure 3 A schematic diagram of channel allocation according to an embodiment of the present application is shown;

[0040] Figure 4 A schematic diagram of a Markov process for switching modulation modes according to an embodiment of the present application is shown;

[0041] Figure 5A schematic diagram of a physical layer service data unit according to an embodiment of the present application is shown;

[0042] Figure 6 A schematic diagram of a physical layer transmission frame structure according to an embodiment of the present application is shown;

[0043] Figure 7 A schematic diagram of an application layer frame structure according to an embodiment of the present application is shown;

[0044] Figure 8 A flow chart of a communication method according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0045] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0046] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0047] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0048] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, while others may be combined or partially combined. Therefore, the actual execution order may vary depending on the actual situation.

[0049] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings 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 making creative efforts shall fall within the scope of protection of the present invention.

[0050] The following will describe some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0051] The TDCS cognitive communication system has spectrum sensing capabilities, can change signal waveforms based on the current spectrum state, and has excellent anti-interference characteristics, but is not compatible with currently commonly used protocols such as CSMA\CA. This application combines TDMA time division multiplexing technology with the TDCS system and proposes a TDMA-based TDCS anti-interference communication system. Through the comprehensive design of the physical layer, data link layer, and integrated application layer, combined with the perception and decision-making module, a multi-user cognitive network is built to maintain a relatively stable multi-user communication state in complex communication environments.

[0052] The communication system of the present application is applied to network communication between a TDCS transmitter and a receiver with spectrum sensing and spectrum judgment capabilities. In particular, the communication system requires that users in the network are TDCS cognitive wireless communication devices with spectrum sensing capabilities. The device transmitter includes a spectrum sensing module, a spectrum judgment module, a communication parameter selection module, a convolutional coding module, an interleaving module, a CCSK modulator, and a PSK\QAM modulator; the device receiver includes a channel synchronization module, a channel estimation module, a spectrum sensing module, a spectrum judgment module, a decoder, a deinterleaver, a CCSK demodulator, and a PSK\QAM demodulator.

[0053] TDCS cognitive wireless communication devices can detect the current spectrum status and report the detection results to the network's perception and decision module. TDCS cognitive wireless devices can also change their current signal waveform and modulation mode according to the instructions of the perception and decision module. They can send and receive signals using CCSK, BPSK, QPSK, and 16QAM modulation modes. In this way, they can select a signal waveform with a fast communication rate but poor anti-interference performance when channel conditions are good, and a signal waveform with good anti-interference performance but a slower communication rate when the channel is interfered with.

[0054] For details, see Figure 1 , shows a structural diagram of a TDMA-based TDCS anti-interference communication system according to an embodiment of the present application.

[0055] like Figure 1As shown, this communication system specifically includes:

[0056] Integrated application layer, data link layer, physical layer and perception decision module;

[0057] The integrated application layer is connected to the data link layer, the data link layer is connected to the physical layer, and the perception decision module is connected to the integrated application layer, the data link layer and the physical layer respectively;

[0058] In the data transmission process, the integrated application layer is used to package the message data into application layer frames and transmit them to the data link layer; the data link layer is used to assemble the application layer frames into physical layer service data units and transmit them to the physical layer; the physical layer is used to generate a transmission signal from the physical layer service data units for transmission;

[0059] In the data receiving process, the physical layer is used to demodulate the received data to obtain the physical layer service data unit and transmit it to the data link layer; the data link layer is used to determine whether the receiving address of the received data is correct. If correct, it is transmitted to the integrated application layer; the integrated application layer is used to verify whether the data is correct and store the correct data;

[0060] The perception decision module is used to collect the user's communication status from the integrated application layer, the data link layer and the physical layer during the data sending process and the data receiving process to make network behavior decisions, and pass the decision parameters to the integrated application layer, the data link layer and the physical layer.

[0061] like Figure 1 As shown, the perception decision module obtains spectrum perception data from the physical layer and sends modulation control and channel control to the physical layer; the perception decision module obtains beacon reception status from the data link layer and sends control of the beacon to the data link layer; the perception decision module also obtains communication success rate data from the integrated application layer and controls the channel according to the communication success rate data.

[0062] Exemplarily, the data transmission process of this communication system is as follows:

[0063] 1. The integrated application layer packages the message data into application layer frames and transmits them to the data link layer;

[0064] 2. The data link layer assembles the application layer frame into a physical layer service data unit and transmits it to the physical layer;

[0065] 3. The physical layer assembles the PSDU into a physical layer transmission frame, which is then encoded, interleaved, and modulated to generate a transmit signal for transmission.

[0066] The data receiving process is as follows:

[0067] 1. After the physical layer detects the transmission frame through the synchronization symbol, it demodulates the PSDU according to the packet header information and transmits it to the data link layer;

[0068] 2. The data link layer first determines whether the data receiving address is its own. If so, it passes the data to the integrated application layer; otherwise, it discards it.

[0069] 3. After the integrated application layer determines that the data is correct based on the confirmation number and check digit, it receives the data and stores it locally.

[0070] The perception and decision module interacts with the integrated application layer, data link layer, and physical layer. The perception and decision module collects communication information from each network layer and transmits decision parameters to each network layer.

[0071] In some feasible embodiments, based on the aforementioned solution, the communication system allocates time slots to users in the network through beacon frames.

[0072] For example, the network time slot allocation diagram is as shown in FIG Figure 2 shown.

[0073] There are n users in the network, numbered 1 to n. Each user is allocated a 25ms transmission window, allowing them to choose any transmission time within that window. This allows for a 5ms user guard interval. After receiving the beacon frame, each user begins transmitting after a delay of (n-1)*30ms, based on their user number. A 10ms sensing slot is reserved at the end of each transmission cycle. During this time slot, there are no user signals. All users can use this time slot to sense the electromagnetic spectrum and identify spectrum holes for communication.

[0074] The channel allocation of this communication system is shown in the figure Figure 3 As shown in the figure, six channels are allocated from 552.5 MHz to 642.5 MHz, with center frequencies at 560 MHz, 575 MHz, 590 MHz, 605 MHz, 620 MHz, and 635 MHz, respectively. Each channel has a bandwidth of 15 MHz, of which the signal occupied bandwidth is 10 MHz. The physical layer divides the 10 MHz occupied bandwidth into 64 subcarriers for carrying OFDM symbols. An OFDM symbol contains 52 subcarriers, 48 of which are data subcarriers. Subcarriers -21, -7, 7, and 21 are pilot subcarriers, carrying pilot symbols for channel equalization. The center subcarrier 0 is not used.

[0075] In some feasible embodiments, based on the above solution, the physical layer is configured with four modulation modes: CCSK, BPSK, QPSK and 16QAM.

[0076] It should be noted that, in this embodiment, the physical layer is capable of four modulation modes: CCSK, BPSK, QPSK, and 16QAM, and can switch the modulation mode according to the instructions of the perception decision module. In order to achieve a certain degree of anti-interference function and avoid the switching strategy being easily obtained, the Markov process is used to model the switching strategy to realize the switching of communication parameters. In the actual communication process, the external electromagnetic environment is divided into two conditions: interference and non-interference. In the case of interference, the modulation mode is switched from high order to low order to reduce the bit error rate and improve the anti-interference performance; in the non-interference environment, the modulation mode is switched from low order to high order to increase the communication rate. The Markov process of modulation mode switching is shown in the figure. Figure 4 shown.

[0077] In some feasible embodiments, based on the above-mentioned solution, the physical layer adds a preamble training sequence and a header for synchronization before modulating the physical layer service data unit.

[0078] For example, Figure 5 As shown in Figure 1, the preamble training sequence consists of 10 short training symbols used for automatic gain control, diversity selection, timing acquisition, and coarse frequency offset estimation, and two long training symbols used for channel estimation and fine frequency offset estimation. The header (SIGNAL) field contains the following fields: data rate (RATE), reserved (Reserved), packet length (LENGTH), and parity (Parity). Together, they form a single OFDM symbol, using BPSK modulation.

[0079] In some feasible embodiments, based on the aforementioned solution, the physical layer service data unit includes: a frame control field, a duration field, an address field, a frame sequence number field, a data field, and an error detection field.

[0080] It should be noted that in this embodiment, the data link layer is responsible for controlling the data transmission of users in the network. The data link layer of user No. 1 in the network will periodically send beacon frames. When all users do not receive beacon frames, they will queue the frames sent by the integrated application layer. After receiving the beacon frame, they will wait until the time slot allocated to them and then send them in turn. After receiving the application layer frame, the data link layer assembles it into a physical layer service data unit. The structure of the physical layer service data unit is shown in the figure. Figure 6 The Frame Control field indicates the frame type and function, the Duration field stores the frame duration, the three Addresses store the destination address, source address, and broadcast address of the frame, respectively, the Sequence Control field stores the frame sequence number, the Frame Body field stores data sent by the application layer and can store up to 1500 bytes of data, and finally there is a 4-byte error detection field.

[0081] The beacon frame has the same structure as the ordinary data frame, except that the frame control field is different, which is used to distinguish beacon frames. The frame body stores an 8-byte timestamp for timing synchronization of each user.

[0082] In some feasible embodiments, based on the aforementioned solution, the application layer frame includes a frame sequence number field, a frame ACK number field, an error control field, a data type field, and a data length field.

[0083] It should be noted that, in this embodiment, the integrated application layer first determines whether the data needs to be packetized and sent based on the data size selected by the user. If the data to be sent by the user exceeds the preset maximum frame length, it will be split into multiple data frames and sent in sequence.

[0084] The comprehensive application layer frame structure is as shown in the figure Figure 7 The sequence number uniquely identifies the data packet of this connection. The acknowledgment number (ACK Num) is the sequence number of the next data packet expected to be received from the other party, and is mainly used for checksum and error control. The data type (Data Type) identifies the type of original data to which the data packet belongs. The data length (Data Length) identifies the remaining data length of the data packet after excluding the header.

[0085] The receiving party checks the acknowledgment number in the data packet. If ACK = M, it indicates that it has correctly received all packets before sequence number M. At the same time, when sending, the sequence number of the next expected frame is embedded in the frame body. If the receiving party detects a checksum error in the frame header, the frame will be considered an error frame, discarded, and the error retransmission mechanism will be triggered. When an error occurs, the party receiving the error frame immediately sends a retransmission request to the other party. Upon receiving the retransmission request, the other party retransmits the previous frame.

[0086] During communication, data packets may be lost due to various reasons. If neither party receives any data, they both wait for the other party to transmit, causing the communication process to become deadlocked. The timeout retransmission mechanism can break this deadlock. If the sender of a data packet does not receive an ACK within the timeout period, it resends the previous packet.

[0087] Based on the same inventive concept, an embodiment of the present application further provides a communication method, which is implemented based on the communication system described in any of the above embodiments. Specifically, the method includes:

[0088] During the communication process, the physical layer obtains spectrum sensing data and transmits it to the sensing decision module, which performs modulation control and channel control on the physical layer based on the spectrum sensing data.

[0089] During the communication process, the data link layer obtains the beacon reception status and transmits it to the perception decision module, and the perception decision module controls the beacon sending of the data link layer based on the beacon reception status;

[0090] During the communication process, the integrated application layer obtains the communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data.

[0091] In some feasible embodiments, based on the above solution, the physical layer obtains spectrum sensing data and transmits it to the sensing decision module, and the sensing decision module performs modulation control and channel control on the physical layer based on the spectrum sensing data, including:

[0092] The physical layer determines whether the primary user signal is received based on the data's prior information. If the primary user signal is recognized, the physical layer reports the primary user identifier to the perception decision module, which then switches channels.

[0093] If the main user signal is not identified, it is determined whether there are other interference signals on the current working channel based on the power spectrum amplitude. If interference exists, the interference identifier is reported to the perception decision module. The perception decision module controls the physical layer to gradually reduce the modulation order. If no interference exists, the perception decision module controls the physical layer to gradually increase the modulation order.

[0094] In some feasible embodiments, based on the above solution, the data link layer obtains the beacon reception status and transmits it to the perception decision module. The perception decision module controls the beacon transmission of the data link layer based on the beacon reception status, including:

[0095] If the data link layer fails to receive a beacon frame within the set time, it reports the beacon loss indicator to the perception decision module;

[0096] After the perception decision module detects that the beacon has lost the identifier, it controls the communication system to switch channels.

[0097] In some feasible embodiments, based on the above solution, the integrated application layer obtains communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data, including:

[0098] The integrated application layer continuously calculates the signal reception success rate within a set time period based on the received confirmation number and error checking;

[0099] If the signal reception success rate within the set time period is lower than the set threshold, a low communication success rate flag is reported to the perception decision module;

[0100] After the perception decision module detects the low communication success rate indicator, it controls the network to switch the working channel.

[0101] For example, see Figure 8 , providing a specific example of a communication method.

[0102] 1. When the system starts, the network works on the preset modulation mode and channel, waiting for each layer module to report information;

[0103] 2. The physical layer first determines whether it has received the primary user signal based on prior information. Since the primary user has the highest network authority, if a primary user signal is recognized, the physical layer reports the primary user identifier to the perception decision module, instructing the network to immediately stop sending beacon frames, thereby disconnecting communication. Communication will then be resumed after switching channels to avoid the problem.

[0104] 3. When the physical layer fails to detect the primary user signal, it determines whether there are other interfering signals on the current operating channel based on the power spectrum amplitude. If interference is present, the interference indicator is reported to the perception and decision module. The perception and decision module then controls the physical layer to gradually reduce the modulation order until it reaches CCSK. If the perception and decision module fails to detect the interference indicator, the modulation order is gradually increased until it reaches 16QAM.

[0105] 4. If the data link layer fails to receive a beacon frame within a certain period of time, it will report a beacon loss flag to the perception and decision module, indicating that the network may no longer be operating on the current channel or that there is excessive interference on the current channel. After detecting the beacon loss flag, the perception and decision module will control the communication system to switch channels.

[0106] 5. The integrated application layer will continuously count the signal reception success rate within a certain period of time based on the received confirmation number and error check. If the communication success rate is lower than 30% within the time period, the low communication success rate indicator will be reported to the perception decision module, indicating that the channel is not suitable for long-term communication. The perception decision module will control the network to switch the working channel.

[0107] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in this application. It should be understood that this application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of this application is limited only by the appended claims.

Claims

1. A TDMA-based TDCS anti-interference communication system, applied to network communication between a TDCS transmitter and a receiver with spectrum sensing and spectrum judgment capabilities, characterized in that: include: Integrated application layer, data link layer, physical layer and perception decision module; The integrated application layer is connected to the data link layer, the data link layer is connected to the physical layer, and the perception decision module is connected to the integrated application layer, the data link layer and the physical layer respectively; In the data transmission process, the integrated application layer is used to package the message data into application layer frames and transmit them to the data link layer; the data link layer is used to assemble the application layer frames into physical layer service data units and transmit them to the physical layer; the physical layer is used to generate a transmission signal from the physical layer service data units for transmission; In the data receiving process, the physical layer is used to demodulate the received data to obtain the physical layer service data unit and transmit it to the data link layer; the data link layer is used to determine whether the receiving address of the received data is correct. If correct, it is transmitted to the integrated application layer; the integrated application layer is used to verify whether the data is correct and store the correct data; The perception decision module is used to collect the user's communication status from the integrated application layer, the data link layer and the physical layer during the data sending process and the data receiving process to make network behavior decisions, and pass the decision parameters to the integrated application layer, the data link layer and the physical layer.

2. The communication system according to claim 1, wherein: The communication system allocates time slots to users in the network through beacon frames.

3. The communication system according to claim 1, wherein: The physical layer is provided with four modulation modes: CCSK, BPSK, QPSK and 16QAM.

4. The communication system according to claim 1, wherein: The application layer frame includes a frame sequence number field, a frame ACK number field, an error control field, a data type field and a data length field.

5. The communication system according to claim 1, wherein: The physical layer service data unit includes: a frame control field, a duration field, an address field, a frame sequence number field, a data field and an error detection field. The communication system according to claim 1 , wherein: Before modulating the physical layer service data unit, the physical layer adds a preamble training sequence and header for synchronization.

7. A communication method based on the communication system according to any one of claims 1 to 6, characterized in that: include: During the communication process, the physical layer obtains spectrum sensing data and transmits it to the sensing decision module, which performs modulation control and channel control on the physical layer based on the spectrum sensing data. During the communication process, the data link layer obtains the beacon reception status and transmits it to the perception decision module, and the perception decision module controls the beacon sending of the data link layer based on the beacon reception status; During the communication process, the integrated application layer obtains the communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data.

8. The method according to claim 7, characterized in that The physical layer acquires spectrum sensing data and transmits the spectrum sensing data to the sensing decision module, and the sensing decision module performs modulation control and channel control on the physical layer based on the spectrum sensing data, including: The physical layer determines whether the primary user signal is received based on the data's prior information. If the primary user signal is recognized, the physical layer reports the primary user identifier to the perception decision module, which then switches channels. If the main user signal is not identified, it is determined whether there are other interference signals on the current working channel based on the power spectrum amplitude. If interference exists, the interference identifier is reported to the perception decision module. The perception decision module controls the physical layer to gradually reduce the modulation order. If no interference exists, the perception decision module controls the physical layer to gradually increase the modulation order.

9. The method according to claim 7, characterized in that The data link layer obtains the beacon reception status and transmits it to the perception decision module, and the perception decision module controls the beacon sending of the data link layer based on the beacon reception status, including: If the data link layer fails to receive a beacon frame within the set time, it reports the beacon loss indicator to the perception decision module; After the perception decision module detects that the beacon has lost the identifier, it controls the communication system to switch channels.

10. The method according to claim 7, characterized in that The integrated application layer obtains communication success rate data and transmits it to the perception decision module, and the perception decision module controls the network to switch the working channel based on the communication success rate data, including: The integrated application layer continuously calculates the signal reception success rate within a set time period based on the received confirmation number and error checking; If the signal reception success rate within the set time period is lower than the set threshold, a low communication success rate flag is reported to the perception decision module; After the perception decision module detects the low communication success rate indicator, it controls the network to switch the working channel.

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