Method and apparatus for tropospheric scatter communications

Abstract

The present invention provides a method and device for tropospheric scatter communication. The method includes: receiving a scattering communication signal from a transmitting end, and extracting a noisy training sequence; matching and comparing the noisy training sequence with a local sample database to determine a corresponding noise-free ideal channel estimation result; wherein the local sample database includes an original training sequence and a basic sequence data sample library corresponding to the noisy training sequence; the basic sequence data in the basic sequence data sample library is obtained according to the original training sequence and simulation of different channel response states; and demodulating the scattering communication signal according to the ideal channel estimation result. The present invention can complete channel estimation in combination with the noise-free ideal simulation result, avoid retaining invalid noise signals or filtering out useful signals during the channel estimation process, and improve the accuracy and efficiency of channel state estimation.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a method and device for tropospheric scatter communication. Background Art

[0002] Tropospheric scatter communication uses the scattering effect of the medium in the atmosphere to propagate signals. It can transmit a variety of signals such as voice, pictures, and videos. It is a method for achieving beyond-line-of-sight communication. Scattering communication has the advantages of long single-hop communication distance, strong anti-destruction ability, strong anti-interference, and high confidentiality. At the same time, due to the long transmission distance, the channel of scattering communication is mainly Rayleigh distribution, with obvious multipath fading effect and strong time-varying characteristics.

[0003] At present, broadband frequency hopping is often used in the field of scattering communication, and its frequency implicit diversity advantage is used to combat fading. In the broadband frequency hopping scattering communication system, in order to obtain better demodulation performance and receiving sensitivity, accurate channel estimation is required to obtain channel state information. The typical channel estimation algorithm matches and correlates the received signal with the local training sequence. The correlation result contains useful multipath information and useless noise signals. According to the pre-set noise threshold, the taps below the noise threshold are forced to be set to zero, and this is used as the channel state estimation result for demodulation and equalization. Obviously, the effect of this channel estimation strategy is closely related to the selection of the noise threshold, and it is easy to lose the useful components of the signal, resulting in multipath signals with weak energy being filtered out as noise, or paths with noise energy higher than the threshold being retained, resulting in inaccurate channel estimation results. Summary of the invention

[0004] The embodiment of the present invention provides a method and apparatus for tropospheric scatter communication to solve the problem of inaccurate estimation of existing channel estimation strategies.

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

[0006] receiving a scattered communication signal from a transmitter and extracting a noisy training sequence;

[0007] Matching and comparing the noisy training sequence with a local sample database to determine a corresponding noise-free ideal channel estimation result; wherein the local sample database includes an original training sequence and a basic sequence data sample library corresponding to the noisy training sequence; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states;

[0008] The scattered communication signal is demodulated according to the ideal channel estimation result.

[0009] In a possible implementation manner, before receiving the scattered communication signal from the transmitting end, the method further includes:

[0010] Assigning values ​​and arranging and combining each set channel parameter to determine different channel response states;

[0011] Simulating the original training sequence based on different channel response states to determine a basic sequence data sample library;

[0012] The set channel parameters include the number of multipaths, multipath delay interval, signal sampling rate, maximum Doppler frequency deviation, Doppler division model and average path power.

[0013] In a possible implementation, matching and comparing the noisy training sequence with a local sample database includes:

[0014] Matching the noisy training sequence with the original training sequence to determine a preliminary channel estimation result with noise;

[0015] The noisy training sequence is denoised, and the denoised training sequence is compared with the basic sequence data in the basic sequence data sample library to determine the ideal channel estimation result.

[0016] In a possible implementation, the method further includes: performing verification processing on the demodulated signal;

[0017] The check process is a cyclic redundancy check (CRC), a parity check or a Hamming check.

[0018] In a possible implementation manner, extracting a noisy training sequence includes:

[0019] Performing analog-to-digital conversion and down-conversion processing on the scattered communication signal to obtain a baseband signal;

[0020] Perform shaping matching on the baseband signal, and extract a noisy training sequence according to the shaping matching result.

[0021] In a possible implementation, the number of the noisy training sequences is one or more segments; wherein, the longer the hop length in the scatter communication signal frame structure, the greater the number of the noisy training sequences;

[0022] When multiple noisy training sequences are extracted, corresponding ideal channel estimation results are determined according to each noisy training sequence.

[0023] In a possible implementation, when extracting multiple noisy training sequences, demodulating the scattered communication signal according to the ideal channel estimation result includes:

[0024] Determining the insertion position of each noisy training sequence in the scattered communication signal, and determining the corresponding hopping structure;

[0025] The corresponding hopping structure is demodulated according to the ideal channel estimation result corresponding to each noisy training sequence.

[0026] In a second aspect, an embodiment of the present invention provides a method for tropospheric scatter communication, including:

[0027] Encode the frame to be sent to obtain a coded signal;

[0028] Inserting one or more original training sequences according to the hop number of the coded signal to obtain a group hop signal;

[0029] Performing modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out;

[0030] The more hops there are, the more original training sequences there are; the original training sequences are stored in the local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after obtaining the noisy training sequence according to the radio frequency communication signal.

[0031] In a possible implementation manner, before encoding the frame to be sent to obtain the encoded signal, the method further includes:

[0032] Add a check code to the frame to be sent; wherein the check code is a CRC check code, a parity check code or a Hamming check code.

[0033] In a third aspect, an embodiment of the present invention provides a sending device for tropospheric scatter communication, including:

[0034] A training sequence extraction module, used for receiving a scattered communication signal from a transmitting end and extracting a noisy training sequence;

[0035] A channel estimation module is used to match and compare the noisy training sequence with a local sample database to determine a corresponding noise-free ideal channel estimation result;

[0036] The local sample database includes an original training sequence corresponding to the noisy training sequence and a basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states;

[0037] A demodulation module is used to demodulate the scattered communication signal according to the ideal channel estimation result.

[0038] In a possible implementation manner, the device further includes:

[0039] A combination module, used for assigning values ​​and arranging and combining various set channel parameters to determine different channel response states before receiving the scattered communication signal from the transmitting end;

[0040] A simulation module, used for simulating the original training sequence based on different channel response states to determine a basic sequence data sample library;

[0041] The set channel parameters include the number of multipaths, multipath delay interval, signal sampling rate, maximum Doppler frequency deviation, Doppler division model and average path power.

[0042] In a fourth aspect, an embodiment of the present invention provides a receiving device for tropospheric scatter communication, including:

[0043] The encoding module is used to encode the frame to be sent to obtain an encoded signal;

[0044] A group hopping module, used for inserting one or more original training sequences according to the hop number of the coded signal to obtain a group hopping signal;

[0045] A modulation module, used for performing modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out;

[0046] The more hops there are, the more original training sequences there are; the original training sequences are stored in the local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after obtaining the noisy training sequence according to the radio frequency communication signal.

[0047] The embodiment of the present invention provides a method and device for tropospheric scatter communication, which simulates the training sequence by setting different channel environments in advance, and generates a local sample database based on the simulation results. The local sample database includes an original training sequence corresponding to the noisy training sequence and a basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulation based on the original training sequence and different channel response states. The original training sequence is inserted into the communication signal transmitted by the transmitter, the scattered communication signal from the transmitter is received, and the noisy training sequence after modulation and channel transmission is extracted; the noisy training sequence is matched and compared with the local sample database to determine the corresponding noise-free ideal channel estimation result, and the scattered communication signal is demodulated according to the ideal channel estimation result. The basic sequence data sample library is obtained by simulation under noise-free conditions, and the noisy training sequence is extracted based on the scattered communication signal received from the transmitter, and matched with the basic sequence data sample library obtained by simulation to obtain the channel response state, avoid retaining invalid noise signals or filtering out useful signals, and improve the accuracy and efficiency of channel state estimation. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be 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 paying creative labor.

[0049] Figure 1 This is an application scenario diagram of a method for tropospheric scatter communication provided by an embodiment of the present invention;

[0050] Figure 2 is a flow chart of an implementation method for tropospheric scatter communication provided by an embodiment of the present invention;

[0051] Figure 3 is a schematic structural diagram of a receiving device for tropospheric scatter communication provided by an embodiment of the present invention;

[0052] Figure 4 is a schematic structural diagram of a receiving device for tropospheric scatter communication provided by another embodiment of the present invention;

[0053] Figure 5 is a schematic structural diagram of a sending device for tropospheric scatter communication provided by an embodiment of the present invention;

[0054] Figure 6 It is a schematic diagram of the structure of a sending device for tropospheric scatter communication provided by another embodiment of the present invention. DETAILED DESCRIPTION

[0055] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0056] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0057] Figure 1 A schematic diagram of a flow chart of a method for tropospheric scatter communication provided by an embodiment of the present invention. Figure 1 As shown, the following steps are included:

[0058] S101, receiving a scattered communication signal from a transmitting end and extracting a noisy training sequence.

[0059] S102, matching and comparing the noisy training sequence with the local sample database to determine the corresponding noise-free ideal channel estimation result.

[0060] The local sample database includes an original training sequence corresponding to the noisy training sequence and a basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states.

[0061] In a possible implementation manner, before receiving the scattered communication signal from the transmitting end, the method further includes:

[0062] Assigning values ​​and arranging and combining each set channel parameter to determine different channel response states;

[0063] Simulating the original training sequence based on different channel response states to determine a basic sequence data sample library;

[0064] Among them, the set channel parameters include the number of multipaths, multipath delay interval, signal sampling rate, maximum Doppler frequency deviation, Doppler division model and average path power. That is, six parameters are comprehensively considered in the simulation process. These different parameters are arranged and combined, assigned values ​​within the set range and simulated in the scattering channel simulator. A complete and ideal basic sequence data sample library can be obtained to improve the accuracy and precision of the ideal channel estimation results.

[0065] In an optional embodiment, the multipath number ranges from 1 to 100; the multipath delay interval ranges from 1 microsecond to 1000 microseconds; the signal sampling rate ranges from 2.4 Kbps to 100 Mbps; the maximum Doppler frequency deviation ranges from 0.001 Hz to 30 Hz; different Doppler division models include: Jakes model, Flat model, Rounded model, Bell model, Asymmetric Jakes model, Restricted Jakes model, Gaussian model, BiGaussian model; the average path power ranges from -500 decibels to +500 decibels.

[0066] In an optional embodiment, simulation is performed based on commonly used channel states to reduce the storage volume of the local sample database and improve matching efficiency. Optionally, a channel response state sample library is obtained by simulation with a multipath number range of 1 to 20.

[0067] S103, demodulating the scattered communication signal according to the ideal channel estimation result.

[0068] In an embodiment of the present invention, the original training sequence is simulated by setting different channel environments in advance, and a local sample database is generated based on the simulation results. Wherein, the local sample database includes the original training sequence corresponding to the noisy training sequence and the basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulation based on the original training sequence and different channel response states. The original training sequence is inserted into the communication signal transmitted by the transmitter, the scattered communication signal from the transmitter is received, and the noisy training sequence after modulation and channel transmission is extracted; the noisy training sequence is matched and compared with the local sample database to determine the corresponding noise-free ideal channel estimation result, and the scattered communication signal is demodulated according to the ideal channel estimation result. Wherein, the basic sequence data sample library is obtained by simulation under noise-free conditions, and the noisy training sequence is extracted based on the scattered communication signal received from the transmitter, and matched with the basic sequence data sample library obtained by simulation to obtain the channel response state, avoid retaining invalid noise signals or filtering out useful signals, and improve the accuracy and efficiency of channel state estimation.

[0069] In a possible implementation, matching and comparing the noisy training sequence with the local sample database includes:

[0070] Matching the noisy training sequence with the original training sequence to determine a preliminary channel estimation result with noise;

[0071] The noisy training sequence is denoised, and the denoised training sequence is compared with the basic sequence data in the basic sequence data sample library to determine the ideal channel estimation result.

[0072] In a possible implementation manner, after the noisy training sequence is denoised, the method further includes:

[0073] The denoised training sequence is normalized based on the noisy training sequence and the original training sequence.

[0074] Among them, the channel response state sample library stores a noise-free time domain channel estimation data set, while the channel estimation obtained by training sequence link matching contains noise. The matching search process in the channel response state library adopts a fuzzy recognition method. After matching and denoising the noisy training sequence with the basic sequence data in the local sample database, the training sequence is normalized to eliminate the influence of the time domain channel estimation tap amplitude caused by the transmission power or noise size.

[0075] In a possible implementation, the method further includes: performing check processing on the demodulated signal; wherein the check processing is CRC check, parity check or Hamming check.

[0076] In a possible implementation, extracting a noisy training sequence includes:

[0077] Perform analog-to-digital conversion and down-conversion processing on the scattered communication signal to obtain the baseband signal;

[0078] Perform shaping matching on the baseband signal and extract the noisy training sequence according to the shaping matching result.

[0079] In a possible implementation, the number of noisy training sequences is one or more segments; wherein, the longer the hop length in the scattering communication signal frame structure is, the greater the number of training sequences is;

[0080] When multiple noisy training sequences are extracted, corresponding ideal channel estimation results are determined according to each noisy training sequence.

[0081] According to the different hop lengths of the signal transmitted by the transmitter, the signal transmission time is different, and the channel state will change during the signal transmission process. Therefore, the transmitter adjusts the number of inserted original training sequences based on the longer hop length in the scattered communication signal frame structure, and the receiver estimates the channel of the adjacent scattered communication signals based on the received modulated training sequences to achieve accurate reception of the entire signal.

[0082] In a possible implementation, when extracting multiple noisy training sequences, demodulating the scattered communication signal according to the ideal channel estimation result includes:

[0083] Determine the insertion position of each noisy training sequence in the scattered communication signal, and determine the corresponding hopping structure;

[0084] The corresponding hopping structure is demodulated according to the ideal channel estimation result corresponding to each noisy training sequence.

[0085] After the insertion position of each noisy training sequence in the scattered communication signal is determined, the hop structure corresponding to each noisy training sequence is determined based on the number of noisy training sequences and the hop length in the scattered communication signal frame structure to avoid omission or uneven demodulation of the hop structure.

[0086] Figure 2 A schematic diagram of a flow chart of a method for tropospheric scatter communication provided by an embodiment of the present invention. Figure 2 As shown, the following steps are included:

[0087] S201, encode the frame to be sent to obtain an encoded signal. Optionally, the encoding method includes: Turbo encoding and LDPC encoding.

[0088] S202, insert one or more original training sequences according to the hop number of the coded signal to obtain a group hop signal.

[0089] S203, performing modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out.

[0090] The more hops there are, the more original training sequences there are; the original training sequences are stored in a local sample database at the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after obtaining the noisy training sequence based on the radio frequency communication signal.

[0091] In a possible implementation, before encoding the frame to be sent to obtain the encoded signal, the method further includes: adding a check code to the frame to be sent, wherein the check code is a CRC check code, a parity check code or a Hamming check code.

[0092] In this embodiment, at the receiving end, different channel environments are set in advance to simulate the training sequence, and a local sample database is generated based on the simulation results. Among them, the local sample database includes the original training sequence corresponding to the noisy training sequence and the basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states. The original training sequence is inserted into the communication signal transmitted by the transmitting end, and the frame to be transmitted is encoded to obtain a coded signal; one or more segments of the original training sequence are inserted according to the number of hops of the coded signal to obtain a group hop signal; the group hop signal is modulated, mapped, shaped, filtered and converted to analog to digital to obtain a radio frequency communication signal and sent out. Among them, the more hops, the more original training sequences; the original training sequence is stored in the local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after the noisy training sequence is obtained according to the radio frequency communication signal analysis, which can avoid the receiving end retaining invalid noise signals or filtering out useful signals during the signal analysis process, thereby improving the accuracy and efficiency of channel state estimation.

[0093] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0094] The following is an embodiment of the device of the present invention. For details not described in detail therein, reference may be made to the corresponding method embodiment described above.

[0095] Figure 3 A schematic diagram of the structure of a receiving device for tropospheric scatter communication provided by an embodiment of the present invention is shown. For ease of description, only the parts related to the embodiment of the present invention are shown, which are described in detail as follows:

[0096] like Figure 3 As shown, the receiving device for tropospheric scatter communication includes: a training sequence extraction module 301, a channel estimation module 302 and a demodulation module 303.

[0097] The training sequence extraction module 301 is used to receive the scattered communication signal from the transmitting end and extract the noisy training sequence.

[0098] The training sequence extraction module 301 includes: an analog-to-digital conversion unit, a digital lower sideband unit, a shaping matched filter unit and a training sequence extraction unit.

[0099] The channel estimation module 302 is used to match the training sequence with the basic sequence data in the local sample database and determine the corresponding noise-free ideal channel estimation result. The local sample database includes the original training sequence corresponding to the noisy training sequence and the basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states.

[0100] The demodulation module 303 is used to demodulate the scattered communication signal according to the ideal channel estimation result.

[0101] The demodulation module 303 includes a denoising unit, a channel equalization unit, a demodulation mapping unit and a decoding unit.

[0102] In a possible implementation, the device further includes: a first verification module, connected to the demodulation module 303, and configured to verify the received signal and then restore the signal.

[0103] In an embodiment of the present invention, the training sequence is simulated by setting different channel environments in advance, and a local sample database is generated based on the simulation results. The local sample database includes an original training sequence corresponding to the noisy training sequence and a basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulation based on the original training sequence and different channel response states. The original training sequence is inserted into the communication signal transmitted by the transmitter, the scattered communication signal from the transmitter is received, and the noisy training sequence after modulation and channel transmission is extracted; the noisy training sequence is matched and compared with the local sample database to determine the corresponding noise-free ideal channel estimation result, and the scattered communication signal is demodulated according to the ideal channel estimation result. The basic sequence data sample library is obtained by simulation under noise-free conditions, and the noisy training sequence is extracted based on the scattered communication signal received from the transmitter, and matched with the basic sequence data sample library obtained by simulation to obtain the channel response state, avoid retaining invalid noise signals or filtering out useful signals, and improve the accuracy and efficiency of channel state estimation.

[0104] like Figure 4 A receiving device for tropospheric scatter communication is shown, wherein the components of a training sequence extraction module 301 and a demodulation module 303 are shown.

[0105] like Figure 5 As shown, the transmitting device for tropospheric scatter communication includes: a coding module 501, a group hopping module 502 and a modulation module 503.

[0106] The encoding module 501 is used to encode the frame to be sent to obtain an encoded signal.

[0107] The group hopping module 502 is used to insert one or more original training sequences according to the hop number of the coded signal to obtain a group hopping signal, wherein the more hops there are, the more original training sequences there are.

[0108] The modulation module 503 is used to perform modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out.

[0109] In a possible implementation, the modulation module 503 includes a modulation mapping unit, a shaping filter unit, and a digital-to-analog conversion unit.

[0110] like Figure 6 A transmitting device for tropospheric scatter communication is shown, wherein the constituent units of the modulation module 503 are shown.

[0111] In a possible implementation, the device further includes: a second check module connected to the encoding module 501, and configured to add a check code to the frame to be sent. Optionally, the check code is a CRC check code, a parity check code, or a Hamming check code.

[0112] In this embodiment, at the receiving end, different channel environments are set in advance and the training sequence is simulated considering the noise signal, and a local sample database is generated based on the simulation results. Among them, the local sample database includes the original training sequence corresponding to the noisy training sequence and the basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states. The original training sequence is inserted into the communication signal transmitted by the transmitting end, and the frame to be transmitted is encoded to obtain a coded signal; one or more segments of the original training sequence are inserted according to the number of hops of the coded signal to obtain a group hop signal; the group hop signal is modulated, mapped, molded, filtered and converted to analog to digital to obtain a radio frequency communication signal and sent out. Among them, the more hops, the more original training sequences; the original training sequence is stored in the local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after the noisy training sequence is obtained according to the radio frequency communication signal analysis, which can avoid the receiving end retaining invalid noise signals or filtering out useful signals during the signal analysis process, thereby improving the accuracy and efficiency of channel state estimation.

[0113] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0114] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0115] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for tropospheric scatter communication, used at a receiving end, characterized in that: include: receiving a scattered communication signal from a transmitter and extracting a noisy training sequence; Matching and comparing the noisy training sequence with a local sample database to determine a corresponding noise-free ideal channel estimation result; wherein the local sample database includes an original training sequence and a basic sequence data sample library corresponding to the noisy training sequence; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states; Demodulating the scattered communication signal according to the ideal channel estimation result; The matching and comparison processing of the noisy training sequence with the local sample database includes: Matching the noisy training sequence with the original training sequence to determine a preliminary channel estimation result with noise; The noisy training sequence is denoised, and the denoised training sequence is compared with the basic sequence data in the basic sequence data sample library to determine the ideal channel estimation result.

2. The method according to claim 1, characterized in that Before receiving the scattered communication signal from the transmitting end, the method further includes: Assigning values ​​and arranging and combining each set channel parameter to determine different channel response states; Simulating the original training sequence based on different channel response states to determine a basic sequence data sample library; The set channel parameters include the number of multipaths, multipath delay interval, signal sampling rate, maximum Doppler frequency deviation, Doppler division model and average path power.

3. The method according to claim 1, characterized in that The step of extracting a noisy training sequence comprises: Performing analog-to-digital conversion and down-conversion processing on the scattered communication signal to obtain a baseband signal; Perform shaping matching on the baseband signal, and extract a noisy training sequence according to the shaping matching result.

4. The method according to claim 1, characterized in that: The number of the noisy training sequences is one or more segments; wherein, the longer the jump length in the scatter communication signal frame structure is, the greater the number of the noisy training sequences is; When multiple noisy training sequences are extracted, corresponding ideal channel estimation results are determined according to each noisy training sequence.

5. The method according to claim 4, characterized in that When extracting multiple noisy training sequences, demodulating the scattered communication signal according to the ideal channel estimation result includes: Determining the insertion position of each noisy training sequence in the scattered communication signal, and determining the corresponding hopping structure; The corresponding hopping structure is demodulated according to the ideal channel estimation result corresponding to each noisy training sequence.

6. A method for tropospheric scatter communication, used at a transmitting end, characterized in that: include: Encode the frame to be sent to obtain a coded signal; Inserting one or more original training sequences according to the hop number of the coded signal to obtain a group hop signal; Performing modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out; The more hops there are, the more original training sequences there are; the original training sequences are stored in a local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after obtaining the noisy training sequence according to the radio frequency communication signal; Wherein, determining the corresponding noise-free ideal channel estimation result includes: Matching the noisy training sequence with the original training sequence to determine a preliminary channel estimation result with noise; The noisy training sequence is denoised, and the denoised training sequence is compared with basic sequence data in a basic sequence data sample library to determine the ideal channel estimation result.

7. A receiving device for tropospheric scatter communication for executing the method for tropospheric scatter communication according to any one of claims 1 to 5, characterized in that: include: A training sequence extraction module, used for receiving a scattered communication signal from a transmitting end and extracting a noisy training sequence; A channel estimation module is used to match and compare the noisy training sequence with a local sample database to determine a corresponding noise-free ideal channel estimation result; wherein the local sample database includes an original training sequence corresponding to the noisy training sequence and a basic sequence data sample library; the basic sequence data in the basic sequence data sample library is obtained by simulating the original training sequence and different channel response states; A demodulation module is used to demodulate the scattered communication signal according to the ideal channel estimation result.

8. The receiving device according to claim 7, characterized in that Also includes: A combination module, used for assigning values ​​and arranging and combining various set channel parameters to determine different channel response states before receiving the scattered communication signal from the transmitting end; A simulation module, used for simulating the original training sequence based on different channel response states to determine a basic sequence data sample library; The set channel parameters include the number of multipaths, multipath delay interval, signal sampling rate, maximum Doppler frequency deviation, Doppler division model and average path power.

9. A transmitting device for tropospheric scatter communication for executing the method for tropospheric scatter communication according to claim 6, characterized in that: include: The encoding module is used to encode the frame to be sent to obtain an encoded signal; A group hopping module, used for inserting one or more original training sequences according to the hop number of the coded signal to obtain a group hopping signal; A modulation module, used for performing modulation mapping, shaping filtering and digital-to-analog conversion on the group hopping signal to obtain a radio frequency communication signal and send it out; The more hops there are, the more original training sequences there are; The original training sequence is stored in a local sample database of the receiving end, so that the receiving end can determine the corresponding noise-free ideal channel estimation result after obtaining the noisy training sequence according to the radio frequency communication signal.

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