6G conduction signal fusion method, device and system for space-air-ground integration

Abstract

The invention relates to a 6G conduction signal fusion method, device and system for space-air-ground integration. The method comprises the following steps: generating a conduction fusion signal at a transmitting end; modulating the conduction fusion signal from a time delay-Doppler domain to a time delay-time domain, and performing parallel-serial conversion to obtain a time domain conduction fusion signal; quickly capturing a satellite at a receiving end; after a satellite is captured, a received time domain conduction fusion signal is converted and restored to obtain an accurately estimated fractional Doppler value and fractional time delay, a channel matrix is reconstructed, data demodulation is performed by using the channel matrix, and navigation message information of the captured satellite is obtained; doppler positioning is carried out by using the fractional Doppler value and satellite information to obtain coarse positioning estimation of a receiver; and according to the four groups of navigation message information and the four groups of pseudo-ranges, Doppler positioning correction values are calculated to correct coarse positioning estimation of the receiver, and 6G conduction signal fusion transmission is realized. The method can improve the signal spectrum efficiency and the satellite utilization rate.

Description

Technical Field

[0001] The present application relates to the field of satellite navigation technology, and in particular to a 6G communication and navigation signal fusion method, device and system for space-ground integration. Background Art

[0002] The services obtained by mobile phone users around the world mainly come from ground communication networks, but they only cover about 6% of the earth's surface. In order to achieve the goal of "anyone, anytime, anywhere" being able to communicate, mobile phones directly connected to satellites have become a hot spot for integrated space-ground network applications for the general public. At the same time, low-orbit satellites can provide higher-precision positioning services due to their advantages of high landing level and low latency. They are an important supplement to medium- and high-orbit navigation satellites such as Beidou. Communication and navigation systems are all developing in the direction of low-orbit satellites. However, the communication and navigation satellite systems in traditional space-based information systems are isolated and information is separated, which makes it difficult to meet the needs of popular, time-efficient, and integrated satellite application services. The following serious problems exist:

[0003] 1) Duplication of construction is costly: Many countries around the world are promoting the construction of large-scale low-orbit satellite constellations. Some countries plan to build tens of thousands of satellites, which is expected to cost billions of RMB. If the constellation is limited to communications and a navigation constellation is built separately, it will lead to a waste of resources and unnecessary high expenses.

[0004] 2) Spectrum resources are becoming increasingly scarce: With the rapid increase in the number of satellite systems, spectrum resources for communication and navigation have become particularly scarce. Low-orbit satellite systems serve the world, and frequency band sharing is prone to interference. Dedicated frequency bands are very scarce. If communication and navigation systems occupy them separately, the spectrum shortage will be further exacerbated.

[0005] 3) Separation and development and backward performance: Communication and navigation satellite information are separated and services lag behind. Currently, only "forwarding fusion" is carried out by terminals, which is difficult to meet the future 6G's "one network, multiple functions" and "integrated services" requirements.

[0006] With the exploration of 6G technology, mobile communication and navigation positioning have formed a two-way interactive trend. Therefore, the integrated design of mobile communication and satellite navigation is the general trend. The integrated communication and navigation system based on low-orbit satellites has become an important development direction of 6G space-ground integration technology. It is very necessary to carry out relevant technical research and design communication and navigation fusion signals that are suitable for it. At present, the research and construction of 6G low-orbit satellite communication and navigation integration systems at home and abroad have achieved certain results, but the world's major LEO systems have different focuses on communication and navigation functions, such as the existing Starlink system, the second-generation Iridium (Iridium-NEXT) system, and the Beidou short message system, which cannot deeply couple the two systems well to meet the requirements of the new generation of 6G communication application scenarios.

[0007] Different from medium and high orbit satellites and ground communications, low orbit satellites transit at extremely high speeds. Traditional OFDM modulation will cause serious inter-subcarrier interference, and performance will deteriorate sharply. To add navigation and positioning functions to the low orbit communication system, the following system difficulties need to be solved:

[0008] 1) The scale of low-orbit satellite constellations is large, and the complexity of multi-satellite capture is high. The "Starlink" plan plans to launch up to 40,000 satellites. If the traditional CDMA algorithm is used, the signal capture time may be extended to 30 minutes or even longer, which cannot meet the real-time requirements of 6G.

[0009] 2) Low-orbit satellite channels are highly dynamic and difficult to track accurately. Accurately estimating the Doppler frequency is crucial for subsequent positioning and communication. However, the high dynamic effects of low-orbit satellites pose a severe challenge to signal processing. The risk of losing lock in traditional frequency-locked loop technology is as high as 49.7% when dealing with such high-dynamic scenarios.

[0010] 3) The demand for communication and navigation signals is obviously different, and the real-time positioning accuracy is poor. In the low-orbit communication system, if the four-star positioning method of medium and high-orbit satellites is used, although the accuracy is high, it requires four-fold coverage, which does not meet the single-fold coverage standard of the communication system.

[0011] Therefore, it is of great practical significance to design a new communication and navigation deep fusion signal system, realize one network with multiple functions, improve signal spectrum efficiency and satellite utilization, and enable the integrated construction of 6G space, air, and land. Summary of the invention

[0012] Based on this, it is necessary to provide a 6G communication and navigation signal fusion method, device and system for the integration of air, space and land, which can realize one network with multiple functions and improve signal spectrum efficiency and satellite utilization, in response to the above technical problems.

[0013] A 6G communication and guidance signal fusion method for air-ground integration, the method comprising:

[0014] At the transmitting end, navigation data and communication service data are acquired and a pseudo-random sequence is generated; after channel coding, BPSK mapping and QPSK mapping are performed on the navigation data and communication service data, the pseudo-random sequence is input into the delay-Doppler domain grid based on OTFS to generate a communication and guidance fusion signal;

[0015] According to the symplectic inverse Fourier transform and Heisenberg transform, the conduction-conduction fusion signal is modulated from the delay-Doppler domain to the delay-time domain, and parallel-to-serial conversion is performed to obtain the time-domain conduction-conduction fusion signal and then sent using an antenna;

[0016] At the receiving end, a pseudo-random sequence identical to that at the transmitting end is generated and converted from parallel to serial to generate a time domain sequence. The time domain sequence is correlated with the received time domain convolution fusion signal, and the satellite is quickly captured at the point where the correlation value is maximum. After capturing the satellite, the received time domain convolution fusion signal is converted from serial to parallel, Wigner transform, and SFFT transform, restored to the delay-Doppler domain grid, and correlated with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay.

[0017] Reconstruct the channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and use the channel matrix to demodulate the communication service data and navigation data to obtain the navigation message information of the captured satellite;

[0018] The loop is tracked based on the accurately estimated fractional delay to obtain the signal propagation time and multiply it by the speed of light to obtain the signal propagation distance. The signal propagation distance is used as the distance between the satellite and the target receiver and is defined as the pseudorange.

[0019] Doppler positioning is performed using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and navigation message information from four satellites is obtained, the Doppler positioning correction value is calculated based on the four sets of navigation message information and four sets of pseudoranges;

[0020] The receiver’s rough positioning estimate is corrected based on the Doppler positioning correction value to achieve 6G communication and guidance signal fusion transmission.

[0021] The above-mentioned 6G communication and navigation signal fusion method, device and system for space-ground integration, the present application generates a communication and navigation fusion signal by placing the navigation signal, communication signal and pseudo-random sequence together in the delay-Doppler domain grid, and placing the communication and navigation data together with the pseudo-random sequence in the delay-Doppler domain, thereby realizing the inter-symbol fusion of communication and navigation data, and can provide unified terminals and integrated services for mass customers and thousands of industries. The receiving end uses the pseudo-random sequence for channel estimation to avoid interference between the two. The fused signal is modulated on the 6G alternative signal OTFS. Compared with the traditional time-frequency domain, the sparsity of the OTFS delay-Doppler domain has very strong robustness to the high dynamic channels of low-orbit satellites; due to the fast movement speed of low-orbit satellites, the Doppler and delay differences of different satellite signals are large, and the same pseudo-random sequence can also be used to distinguish satellites, shortening the capture time to one thousandth of the traditional method. By utilizing the commonality of pseudo-random sequences in satellite navigation systems and satellite communication systems, the proposed delay-Doppler domain precise channel estimation can simultaneously complete pseudo-range measurement, Doppler positioning, data demodulation and other functions; at the same time, considering the contradiction between the single-weight coverage requirements of communication satellites and the single-weight coverage of navigation satellites, Doppler positioning is used when there are less than four stars, and pseudo-range positioning is used for correction after accumulating data from four stars, which greatly improves positioning accuracy. Starting from the design of the signal system, this application realizes the deep integration of navigation and communication, and provides a navigation and communication solution with low construction cost, high spectrum efficiency, obvious performance advantages, advanced technical routes, and rich application scenarios for the construction of 6G space-ground integrated systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a flow chart of a 6G communication and guidance signal fusion method for air-ground integration in one embodiment;

[0023] Figure 2 is a delay-Doppler domain modulation diagram in one embodiment;

[0024] Figure 3 A scene diagram of a semi-physical test in an embodiment;

[0025] Figure 4 It is a demodulation constellation comparison diagram in another embodiment; (a) is an OFDM demodulation constellation diagram; (b) is an OTFS demodulation constellation diagram;

[0026] Figure 5 This is a structural block diagram of a 6G communication and guidance signal fusion device for air-space-ground integration in one embodiment;

[0027] Figure 6 This is a structural diagram of a 6G communication and guidance signal fusion system for air-space-ground integration in one embodiment. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] In one embodiment, Figure 1 As shown, a 6G communication and guidance signal fusion method for air-ground integration is provided, including the following steps:

[0030] Step 102, obtaining navigation data and communication service data at the transmitting end and generating a pseudo-random sequence; performing channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data and inputting the pseudo-random sequence into a delay-Doppler domain grid based on OTFS to generate a communication-guide fusion signal.

[0031] Navigation data nav [n], communication service data com [n] is channel coded, and then BPSK and QPSK mapping are performed respectively, and the pseudo-random sequence c[n] used for navigation acquisition and channel estimation is placed in the delay-Doppler domain grid of OTFS. Figure 2 As shown, the communication and navigation fusion signal x[k,l] is formed, k=0,...,N-1, l=0,...,M-1. Since low-orbit satellites move very fast, the Doppler and delay of different satellites reaching the receiver at the same time will be quite different. Therefore, the pseudo-random sequences inserted by all satellites are the same, avoiding the traversal search of satellites and shortening a lot of search time. At the same time, the communication and navigation data are placed together with the pseudo-random sequence in the delay-Doppler domain to achieve the inter-symbol fusion of communication and navigation data, which can provide unified terminals and integrated services for mass customers and thousands of industries.

[0032] Step 104, modulate the conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, perform parallel-serial conversion, obtain the time domain conduction fusion signal, and then send it through the antenna.

[0033] Step 106, at the receiving end, a pseudo-random sequence identical to that at the transmitting end is generated, and a parallel-to-serial conversion is performed to generate a time domain sequence, and the time domain sequence is correlated with the received time domain conduction fusion signal, and the satellite is quickly captured at the point where the correlation value is maximum; after capturing the satellite, the received time domain conduction fusion signal is serial-to-parallel converted, Wigner transformed, and SFFT transformed, restored to a delay-Doppler domain grid, and correlated with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay.

[0034] During channel transmission, h(τ,v) can be used to represent the channel response:

[0035] h(τ,v)=h0δ(τ-τ0)δ(v-v0)

[0036] For the transmitted signal s(t), τ0 and v0 represent the channel delay and Doppler frequency shift respectively. On the DD domain grid, we use l τ and l τ are integer values ​​representing the delay and Doppler grid of the channel, respectively, and are defined as

[0037]

[0038] in: represents the fractional part of the Doppler frequency, l τ and k v Take integers respectively. The received signal after channel fading can be expressed as:

[0039]

[0040] Where: v(t) is additive noise.

[0041] r(t) is first converted into a digital intermediate frequency signal by the RF front-end processing. The receiver generates the same pseudo-random sequence, which is continuously correlated with the received signal r(t) to perform a two-dimensional traversal search for the channel parameters. The intersection of a Doppler frequency value and a delay value is called a search unit (τ est ,v est ), calculate the related function through two-dimensional traversal search Find the channel parameters (τ est ,v est ) to satisfy Complete the rough estimation of channel parameters and rapid capture of satellites.

[0042] It is worth noting that due to the fast movement speed of satellites, the Doppler and delay differences between different satellites are large. Therefore, using the same pseudo-random sequence for different satellites can also achieve satellite differentiation, avoiding three-dimensional search for satellites and greatly improving the capture speed.

[0043] After completing satellite acquisition and time synchronization, the receiver converts the received signal r(t) into serial-to-parallel, reconstructs the delay-time domain grid, and performs Wigner transform and SFFT transform on the delay-time domain grid to restore the delay-Doppler domain grid. The pseudo-random sequence in the delay-Doppler domain is further used for correlation operations to achieve accurate estimation of fractional Doppler and fractional delay. The specific process is as follows:

[0044] The receiving end recovers the received signal y affected by the channel according to the parameter value of the center point of the search unit C (t):

[0045]

[0046] Further C (t) Perform Wigner transform and SFFT transform to obtain the delay-Doppler domain symbol y C [k,l]:

[0047]

[0048] in: Obeying Gaussian distribution, h w (·) is the sampled impulse response function:

[0049]

[0050] h w (ν′,τ′) represents the circular convolution of the windowed channel response

[0051] h w (ν′,τ′)=∫∫h(τ,ν)w(ν′-ν,τ′-τ)e -j2πντ dτdν,

[0052]

[0053] In order to accurately estimate the parameters in the channel transmission, the upper and lower boundary values ​​of the Doppler frequency of the corresponding search unit are selected to restore y U [k,l] and y L [k,l]. Among them, y U [k,l](y L [k,l]) corresponds to a Doppler frequency that is lower than y C The Doppler frequency used in [k,l] is half the search step size (high v bin / 2).

[0054] The three PN sequences y recovered according to different Doppler frequencies U [k,l],y C [k,l] and y L [k,l] are cross-correlated with y[k,l] generated by the pseudo-random sequence generator to obtain the cross-correlation result R(y,y U ),R(y,y C ),R(y,y L ). If there is an estimation bias, the estimated bias δ ​​of the Doppler frequency can be obtained by the lead-lag method v :

[0055]

[0056] By comparing R(y,y U ) and R(y,y L ) correlation results, from which the position of the top of the main peak of the PN code autocorrelation function is deduced, and then the Doppler frequency estimate is corrected after passing through the energy frequency detector of the code based on the pseudo-random sequence

[0057]

[0058] Among them, δ v represents the correction amount, and the corrected estimate Move to the center of the search unit. After multiple cycles, until R(y,y U )≈R(y,y L ) until the final accurate Doppler estimation frequency is output The same principle is used for delay, outputting accurate delay estimation

[0059] Fractional Doppler and fractional delay are estimated using pseudo-random sequences in the delay-Doppler domain to improve channel estimation accuracy. This method can be used for navigation signal tracking, pseudo-range measurement, and Doppler positioning at the same time.

[0060] Step 108, reconstructing the channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and using the channel matrix to demodulate the communication service data and navigation data to obtain the navigation message information of the captured satellite.

[0061] The channel matrix G is reconstructed based on the Doppler and delay information, and channel equalization is performed based on the channel matrix G and the minimum mean square error criterion to recover the delay-Doppler domain communication and guidance fusion signal.

[0062]

[0063] in: is the noise variance, I MN It is a unit array, and then the communication and navigation data are BPSK / QPSK de-mapped and channel decoded to obtain communication business data and navigation message information, and further obtain satellite operation status and satellite coordinate information.

[0064] The signal and channel are represented in the delay-Doppler domain, and the channel response of the satellite-to-ground high dynamic channel is sparse, which greatly reduces the impact of the high dynamic channel on signal transmission.

[0065] Step 110, tracking the loop according to the accurately estimated fractional delay, obtaining the signal propagation time and multiplying it by the speed of light to obtain the signal propagation distance, taking the signal propagation distance as the distance between the satellite and the target receiver and defining it as a pseudorange.

[0066] The loop is tracked using the accurately estimated fractional delay to obtain the signal propagation time. The signal propagation distance is obtained by multiplying the signal propagation time by the speed of light, which is used as the distance between the satellite and the target receiver and is defined as the pseudorange.

[0067]

[0068] Here, c represents the speed of light.

[0069] Step 112, using fractional Doppler values ​​and satellite information to perform Doppler positioning, to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and navigation message information of four satellites is obtained, a Doppler positioning correction value is calculated based on four sets of navigation message information and four sets of pseudoranges; the receiver's rough estimate of positioning is corrected based on the Doppler positioning correction value to achieve 6G communication and guidance signal fusion transmission.

[0070] Assume the satellite position is Speed The satellite transmission frequency is f s ; The receiver position is Speed The receiving frequency of the measuring station is f r , the Doppler frequency is For a stationary receiver, the Doppler frequency can be expressed as

[0071]

[0072] in, is the radial unit vector pointing from the satellite to the receiver. Consider the receiver clock error δf r When the frequency measurement error εf is equal to εf, the instantaneous Doppler observation equation of the station can be written as

[0073]

[0074] in, is the three-dimensional coordinates and clock error of the measuring station, is the parameter to be determined, and the initial estimated values ​​of the target position and clock error are

[0075]

[0076] After Taylor expansion and linearization of the observation equation, for the observed quantities at n moments, the least squares form of Doppler positioning is as follows:

[0077]

[0078] Where: G is the transfer matrix, ∈ is the error vector, k is the number of iterations, is the estimated solution value obtained at the kth iteration, and Δf is the difference matrix between the Doppler observation value and the estimated value. It can be seen that the entire equation is now a linear equation about the increment.

[0079] Therefore, the receiver position change can be calculated

[0080]

[0081] Update later The value of gets the rough estimate of the receiver position

[0082]

[0083] After further accumulating the pseudorange data of the four satellites, the Doppler positioning value is corrected using the Doppler positioning correction value to obtain the final receiver position estimate.

[0084]

[0085] Where: Δu ρ It indicates that the Doppler positioning correction value is calculated based on four sets of navigation message information and four sets of pseudoranges. The process of calculating the Doppler positioning correction value based on four sets of navigation message information and four sets of pseudoranges is the prior art and will not be described in detail in this application.

[0086] To improve positioning accuracy, when there are less than four visible satellites, Doppler positioning is used to roughly estimate the positioning position. After reaching four satellites, pseudo-range positioning is used for correction. The "Doppler + pseudo-range" fusion positioning greatly improves positioning accuracy. At the same time, the technical route of this application is not limited to satellite-to-ground channels, but is universal for drone aerial nodes and ground network nodes.

[0087] The above-mentioned 6G communication and navigation signal fusion method for air-space-ground integration, this application generates a communication and navigation fusion signal by placing the navigation signal, communication signal and pseudo-random sequence together in the delay-Doppler domain grid, and placing the communication and navigation data together with the pseudo-random sequence in the delay-Doppler domain, thereby realizing the inter-symbol fusion of communication and navigation data, and can provide unified terminals and integrated services for mass customers and thousands of industries. The receiving end uses a pseudo-random sequence for channel estimation to avoid interference between the two. The fused signal is modulated on the 6G alternative signal OTFS. Compared with the traditional time-frequency domain, the sparsity of the OTFS delay-Doppler domain has very strong robustness to the high dynamic channels of low-orbit satellites; due to the fast movement speed of low-orbit satellites, the Doppler and delay differences of different satellite signals are large, and the same pseudo-random sequence can also be used to distinguish satellites, shortening the capture time to one thousandth of the traditional method. By utilizing the commonality of pseudo-random sequences in satellite navigation systems and satellite communication systems, the proposed delay-Doppler domain precise channel estimation can simultaneously complete pseudo-range measurement, Doppler positioning, data demodulation and other functions; at the same time, considering the contradiction between the single-weight coverage requirements of communication satellites and the single-weight coverage of navigation satellites, Doppler positioning is used when there are less than four stars, and pseudo-range positioning is used for correction after accumulating data from four stars, which greatly improves positioning accuracy. Starting from the design of the signal system, this application realizes the deep integration of navigation and communication, and provides a navigation and communication solution with low construction cost, high spectrum efficiency, obvious performance advantages, advanced technical routes, and rich application scenarios for the construction of 6G space-ground integrated systems.

[0088] In one embodiment, after performing channel coding, BPSK mapping and QPSK mapping on navigation data and communication service data, the navigation data and communication service data are input into a delay-Doppler domain grid based on OTFS with a pseudo-random sequence to generate a communication and guidance fusion signal, including:

[0089] The navigation data is converted into binary and then channel-coded to generate a navigation data stream. The communication service data is also channel-coded to generate a communication data stream. The navigation data stream and the communication data stream are modulated together with a pseudo-random sequence on an M×N OTFS-based delay-Doppler domain grid after BPSK mapping and QPSK mapping to generate a communication-guide fusion signal:

[0090] x[k,l],k=0,...,N-1,l=0,...,M-1

[0091] Among them, k is the delay axis index, l is the Doppler axis index, M is the number of subcarriers, and N is the number of symbols.

[0092] In one embodiment, the conduction fusion signal is modulated from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, and parallel-to-serial conversion is performed to obtain the time-domain conduction fusion signal, including:

[0093] The delay-Doppler domain is discretized into an M×N grid, and the symplectic inverse Fourier transform is used to transform the conduction fusion signal x[k,l] in the delay-Doppler domain into the time-frequency domain X[n,m]:

[0094]

[0095] Set the time-frequency grid to a discrete M×N grid, and then use the Heisenberg transform to transform the symbol X[n,m] on the time-frequency grid through the pulse waveform g tx (t) Generate the time domain conduction fusion signal as

[0096]

[0097] Wherein, n is the time axis index, m is the frequency axis index, t is the time, T is the symbol duration, and Δf is the subcarrier spacing.

[0098] In one embodiment, the received time domain conduction fusion signal is

[0099]

[0100] Among them, v(t) is additive noise, h0 represents the amplitude response, τ0, v0 represent the channel delay and Doppler frequency shift respectively.

[0101] In one embodiment, the time domain sequence is correlated with the received time domain communication and conduction fusion signal, and the satellite is quickly captured at the point where the correlation value is maximum, including:

[0102] The received time-domain fusion signal r(t) is first converted into a digital intermediate frequency signal by the RF front-end processing. The time-domain sequence is continuously correlated with the received time-domain fusion signal, and a two-dimensional traversal search is performed on the channel parameters. The intersection of a Doppler frequency value and a delay value is called a search unit (τ est ,v est ), calculate the related function through two-dimensional traversal search And find the channel parameters (τ est ,v est ), when satisfied Complete the rapid capture of the satellite in time.

[0103] In one embodiment, after capturing the satellite, the received time-domain conduction fusion signal is subjected to serial-to-parallel conversion, Wigner transformation, and SFFT transformation, restored to a delay-Doppler domain grid, and correlated with a pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay, including:

[0104] After capturing the satellite, the received time domain conduction fusion signal is converted into serial and parallel to restore the received signal y affected by the channel C (t):

[0105]

[0106] For C (t) Perform Wigner transform and SFFT transform to obtain the delay-Doppler domain symbol y C [k,l]:

[0107]

[0108] in: Obeying Gaussian distribution, h w (·) is the sampled impulse response function:

[0109]

[0110] Among them, h w (ν′,τ′) denotes the circular convolution of the windowed channel response, τ est is the delay estimation, v est is the Doppler estimate;

[0111] Select the upper and lower boundary values ​​of the Doppler frequency of the corresponding search unit to restore y U [k,l] and y L [k,l], where y U [k,l] or y L [k,l]) corresponds to a Doppler frequency that is lower than y C The Doppler frequency used in [k,l] is half the search step higher or lower (high v bin / 2);

[0112] The three PN sequences y recovered according to different Doppler frequencies U [k,l],y C [k,l] and y L [k,l] are cross-correlated with y[k,l] generated by the pseudo-random sequence generator to obtain the cross-correlation result R(y,y U ),R(y,y C ),R(y,y L ), if there is an estimation error, the estimated error δ of the Doppler frequency is obtained according to the lead-lag method v :

[0113]

[0114] By comparing R(y,y U ) and R(y,y L) correlation results, the position of the top of the main peak of the PN code autocorrelation function is calculated, and then the Doppler frequency estimate is corrected after passing through the energy frequency detector of the code based on the pseudo-random sequence.

[0115]

[0116] Among them, δ v represents the correction amount, and the corrected estimate Move to the center of the search unit and output the accurately estimated fractional Doppler value Using the same principle, output an accurate estimate of the fractional delay

[0117] In one embodiment, reconstructing a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, demodulating communication service data and navigation data using the channel matrix, and obtaining navigation message information of the captured satellite also includes:

[0118] The channel matrix G is reconstructed based on the accurately estimated fractional Doppler value and the accurately estimated fractional delay. Channel equalization is performed based on the channel matrix G and the minimum mean square error criterion to recover the delay-Doppler domain conduction fusion signal:

[0119]

[0120] in: is the noise variance, I MN It is a unit array;

[0121] The delay-Doppler domain navigation and navigation fusion signal is subjected to BPSK / QPSK demapping and channel decoding to obtain the navigation message information of the captured satellite.

[0122] In one embodiment, using fractional Doppler values ​​and satellite information to perform Doppler positioning to obtain a rough estimate of the positioning of the receiver includes:

[0123] Assume the satellite position is Speed The satellite transmission frequency is f s , the receiver location is Speed The receiving frequency of the measuring station is f r , the Doppler frequency is Consider the receiver clock error δf r When the frequency measurement error εf is equal to the frequency measurement error εf, the instantaneous Doppler observation equation of the station is calculated as

[0124]

[0125] in, is the three-dimensional coordinates and clock error of the measuring station, and the initial estimated values ​​of the target position and clock error are

[0126]

[0127] After Taylor expansion and linearization of the observation equation, for the observed quantities at n moments, the least squares form of Doppler positioning is as follows:

[0128]

[0129] Where G is the transfer matrix, ∈ is the error vector, k is the number of iterations, Δf is the difference matrix between the Doppler observation and the estimated value, and the calculated receiver position change is

[0130]

[0131] Update later The value of gets the rough estimate of the receiver position

[0132]

[0133] In a specific embodiment, Figure 3 The semi-physical test scenario of this method is demonstrated, and a channel simulator is made by selecting real satellite ephemeris and obtaining navigation message information. The 6G communication and navigation signal fusion method for space-ground integration proposed in this application is applied to complete the signal transmission, reception and demodulation through USRP software radio, and the communication and positioning results are displayed in real time at the receiving end.

[0134] The channel simulator sets the satellite-ground scenario parameters according to the 3GPP specification. At the same time, the parameters of this method are set according to the real satellite ephemeris: the Doppler frequency change rate range is -300 to 300 Hz / s, the subcarrier M = 256, the Doppler grid number N = 64, the subcarrier spacing is 30 kHz, the center frequency is 975 MHz, and the carrier-to-noise ratio at the receiving end is 10.32 dB.

[0135] Comparison scheme: Orthogonal frequency division multiplexing (OFDM) technology, which has been widely used in 5G, is used as the basis for transmitting communication and navigation fusion signals. That is, after the communication signal and navigation signal power domain are superimposed, they are modulated to the carrier through OFDM. The traditional algorithm is used at the transmitting and receiving end. The power proportion of the communication signal is set to 90%, and the power proportion of the navigation and pseudo-random sequence is 5% each. The test results are shown in the figure below. Figure 4 (a) and Figure 4 (b) as shown.

[0136] From the test results, it can be seen that the comparison scheme is compared with the present application method under the same configuration:

[0137] In terms of signal demodulation bit error rate, under the same power configuration, the constellation diagram of this scheme is obviously more concentrated. The signal bit error rate of the communication and conduction fusion scheme based on OTFS is lower than that of the communication and conduction fusion scheme based on OFDM, which can reach 10 -6 , which can meet the communication needs, while OFDM cannot meet the communication needs in high dynamic scenarios. This shows that the integrated communication and guidance signal system based on OTFS can better cope with the impact of high dynamic channels, thereby achieving better transmission reliability.

[0138] In terms of receiver positioning solution, due to the use of algorithms such as fast capture, high-precision channel estimation and fusion positioning of this application, the positioning speed and positioning accuracy of this solution are greatly improved, and the positioning error of 10 meters can be reduced to the meter level. At the same time, due to the lower signal bit error rate of this solution, higher-precision positioning can be achieved under low signal-to-noise ratio.

[0139] In addition, this solution has been extensively tested in UAV scenarios and ground scenarios. The test results show that this method can fully meet the satellite application service needs in all scenarios of air, space and land, and can provide an important reference for the construction of 6G air, space and land integration.

[0140] In summary, the present application provides a 6G communication and guidance signal fusion method, device and system for air-ground integration, which has the following advantages:

[0141] This application completes the integration of 6G communication and navigation symbols for all scenarios in the air, space, and land at the signal system level, providing a unified terminal for mass customers and thousands of industries, which is conducive to improving spectrum utilization, enabling 6G system construction, and reducing the cost of integrated systems.

[0142] All satellites use the same pseudo-random sequence and utilize the Doppler and time delay of low-orbit satellites to distinguish satellites, greatly shortening the capture time of the giant constellation.

[0143] The fused signal is modulated with the 6G alternative signal OTFS modulation method and then sent. OTFS can represent the signal and channel in the delay-Doppler domain. Compared with the traditional time-frequency domain, the delay-Doppler domain is extremely robust to the high dynamic channels of low-orbit satellites.

[0144] The channel is accurately estimated through a pseudo-random sequence in the delay-Doppler domain, and fractional estimates of Doppler and delay are obtained through the redshift and blueshift of the energy discriminator, greatly improving the performance of communication and navigation.

[0145] When there are less than 4 visible satellites, Doppler positioning is used. When the number of visible satellites reaches 4, pseudo-range positioning is used for correction to meet the positioning needs in different environments and improve the positioning accuracy and applicability of the system.

[0146] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0147] In one embodiment, Figure 5 As shown, a 6G communication and guidance signal fusion device for air-ground integration is provided, including: a communication and guidance signal generation module 502, a communication and guidance signal sending module 504, a satellite capture module 506, a channel estimation module 508, a data demodulation module 510, and a fusion positioning module 512, wherein:

[0148] The navigation and communication signal generation module 502 is used to obtain navigation data and communication service data at the transmitting end and generate a pseudo-random sequence; after performing channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data, the pseudo-random sequence is input into the delay-Doppler domain grid based on OTFS to generate a navigation and communication fusion signal;

[0149] The communication and conduction signal sending module 504 is used to modulate the communication and conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, and perform parallel-serial conversion to obtain the time-domain communication and conduction fusion signal and then send it through the antenna;

[0150] The satellite acquisition module 506 is used to generate the same pseudo-random sequence as the transmitting end at the receiving end, perform parallel-to-serial conversion to generate a time domain sequence, perform correlation operation on the time domain sequence and the received time domain conduction fusion signal, and quickly capture the satellite at the point where the correlation value is maximum; after capturing the satellite, perform serial-to-parallel conversion, Wigner transformation and SFFT transformation on the received time domain conduction fusion signal, restore it to the delay-Doppler domain grid and perform correlation operation with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay;

[0151] A channel estimation module 508 is used to reconstruct a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and use the channel matrix to demodulate communication service data and navigation data to obtain navigation message information of the captured satellite;

[0152] The data demodulation module 510 is used to track the loop according to the accurately estimated fractional delay, obtain the propagation time of the signal and multiply it by the speed of light to obtain the propagation distance of the signal, and use the propagation distance of the signal as the distance between the satellite and the target receiver, and define it as a pseudorange;

[0153] The fusion positioning module 512 is used to perform Doppler positioning using fractional Doppler values ​​and satellite information to obtain a rough estimate of the positioning of the receiver; when at least four satellites are accumulated and the navigation message information of the four satellites is obtained, the Doppler positioning correction value is calculated based on the four sets of navigation message information and the four sets of pseudo-ranges; the rough estimate of the positioning of the receiver is corrected according to the Doppler positioning correction value to realize the fusion transmission of 6G communication and guidance signals.

[0154] For the specific definition of a 6G communication signal fusion device for air-space-ground integration, please refer to the definition of a 6G communication signal fusion method for air-space-ground integration mentioned above, which will not be repeated here. Each module in the above-mentioned 6G communication signal fusion device for air-space-ground integration can be implemented in whole or in part through software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0155] In one embodiment, Figure 6 As shown, the system includes a satellite 610 and a receiver 620; the satellite 610 is provided with a communication signal generating module and a communication signal sending module; the receiver 620 is provided with a satellite capturing module, a channel estimating module, a data demodulating module and a fusion positioning module, wherein:

[0156] The navigation and communication signal generation module is used to obtain navigation data and communication service data at the transmitting end and generate a pseudo-random sequence; after performing channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data, the pseudo-random sequence is input into the delay-Doppler domain grid based on OTFS to generate a navigation and communication fusion signal;

[0157] The communication and conduction signal sending module is used to modulate the communication and conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, and perform parallel-serial conversion to obtain the time-domain communication and conduction fusion signal and then send it through the antenna;

[0158] The satellite capture module is used to generate the same pseudo-random sequence as the transmitting end at the receiving end, perform parallel-to-serial conversion to generate a time domain sequence, perform correlation operation on the time domain sequence and the received time domain conduction fusion signal, and quickly capture the satellite at the point where the correlation value is maximum; after capturing the satellite, perform serial-to-parallel conversion, Wigner transformation and SFFT transformation on the received time domain conduction fusion signal, restore it to the delay-Doppler domain grid and perform correlation operation with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay;

[0159] A channel estimation module is used to reconstruct a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and to demodulate the communication service data and navigation data using the channel matrix to obtain the navigation message information of the captured satellite;

[0160] The data demodulation module is used to track the loop according to the accurately estimated fractional delay, obtain the propagation time of the signal and multiply it by the speed of light to obtain the propagation distance of the signal. The propagation distance of the signal is used as the distance between the satellite and the target receiver and is defined as the pseudorange.

[0161] The fusion positioning module is used to perform Doppler positioning using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and the navigation message information of the four satellites is obtained, the Doppler positioning correction value is calculated based on the four sets of navigation message information and four sets of pseudo-ranges; the receiver's rough positioning estimate is corrected based on the Doppler positioning correction value to achieve 6G communication and guidance signal fusion transmission.

[0162] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0163] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A 6G communication and guidance signal fusion method for air-ground integration, characterized in that: The method comprises: Acquire navigation data and communication service data at the transmitting end and generate a pseudo-random sequence; perform channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data and input the pseudo-random sequence into a delay-Doppler domain grid based on OTFS to generate a communication-guide fusion signal; Modulating the conduction-conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, performing parallel-serial conversion, obtaining the time-domain conduction-conduction fusion signal and then transmitting it using an antenna; Generate a pseudo-random sequence identical to that of the transmitting end at the receiving end, perform parallel-to-serial conversion to generate a time domain sequence, perform correlation operation on the time domain sequence and the received time domain conduction fusion signal, and quickly capture the satellite at the point where the correlation value is maximum; after capturing the satellite, perform serial-to-parallel conversion, Wigner transformation, and SFFT transformation on the received time domain conduction fusion signal, restore it to a delay-Doppler domain grid, and perform correlation operation with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay; Reconstructing a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and using the channel matrix to demodulate communication service data and navigation data to obtain navigation message information of the captured satellite; Tracking the loop according to the accurately estimated fractional delay, obtaining the propagation time of the signal and multiplying it by the speed of light to obtain the propagation distance of the signal, taking the propagation distance of the signal as the distance between the satellite and the target receiver, and defining it as a pseudorange; Doppler positioning is performed using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and navigation message information from four satellites is obtained, the Doppler positioning correction value is calculated based on the four sets of navigation message information and four sets of pseudoranges; The rough positioning estimate of the receiver is corrected according to the Doppler positioning correction value to realize 6G communication and guidance signal fusion transmission.

2. The method according to claim 1, characterized in that Channel coding, BPSK mapping and QPSK mapping are performed on the navigation data and the communication service data, and then the data is input into the delay-Doppler domain grid based on OTFS with a pseudo-random sequence to generate a communication and guidance fusion signal, including: The navigation data is converted into binary and then channel-coded to generate a navigation data stream. The communication service data is also channel-coded to generate a communication data stream. The navigation data stream and the communication data stream are modulated together with a pseudo-random sequence on an M×N OTFS-based delay-Doppler domain grid after BPSK mapping and QPSK mapping to generate a communication fusion signal: x[k,l],k=0,...,N-1,l=0,...,M-1 Among them, k is the delay axis index, l is the Doppler axis index, M is the number of subcarriers, and N is the number of symbols.

3. The method according to claim 1, characterized in that According to the symplectic inverse Fourier transform and the Heisenberg transform, the conduction fusion signal is modulated from the delay-Doppler domain to the delay-time domain, and parallel-to-serial conversion is performed to obtain a time-domain conduction fusion signal, including: The delay-Doppler domain is discretized into an M×N grid, and the symplectic inverse Fourier transform is used to transform the conduction fusion signal x[k,l] in the delay-Doppler domain into the time-frequency domain X[n,m]: Set the time-frequency grid to a discrete M×N grid, and then use the Heisenberg transform to transform the symbol X[n,m] on the time-frequency grid through the pulse waveform g tx (t) Generate the time domain conduction fusion signal as Wherein, n is the time axis index, m is the frequency axis index, t is the time, T is the symbol duration, and Δf is the subcarrier spacing.

4. The method according to any one of claims 1 to 3, characterized in that: The received time domain conduction fusion signal is Among them, v(t) is additive noise, h0 represents the amplitude response, τ0, v0 represent the channel delay and Doppler frequency shift respectively.

5. The method according to claim 1, characterized in that The time domain sequence is correlated with the received time domain communication and conduction fusion signal, and the satellite is quickly captured at the point where the correlation value is maximum, including: The received time-domain fusion signal r(t) is first converted into a digital intermediate frequency signal by the RF front-end processing. The time-domain sequence is continuously correlated with the received time-domain fusion signal, and a two-dimensional traversal search is performed on the channel parameters. The intersection of a Doppler frequency value and a delay value is called a search unit (τ est ,v est ), calculate the related function through two-dimensional traversal search And find the channel parameters (τ est ,v est ), when satisfied Complete the rapid capture of the satellite in time.

6. The method according to claim 1, characterized in that After capturing the satellite, the received time-domain fusion signal is converted into serial-to-parallel, Wigner-transformed, and SFFT-transformed, restored to the delay-Doppler domain grid, and correlated with the pseudo-random sequence to obtain the accurately estimated fractional Doppler value and the accurately estimated fractional delay, including: After capturing the satellite, the received time domain conduction fusion signal is converted into serial and parallel to restore the received signal y affected by the channel C (t): For C (t) Perform Wigner transform and SFFT transform to obtain the delay-Doppler domain symbol y C [k,l]: in: Obeying Gaussian distribution, h w (·) is the sampled impulse response function: Among them, h w (ν′,τ′) denotes the circular convolution of the windowed channel response, τ est is the delay estimation, v est is the Doppler estimate; Select the upper and lower boundary values ​​of the Doppler frequency of the corresponding search unit to restore y U [k,l] and y L [k,l], where y U [k,l] or y L [k,l]) corresponds to a Doppler frequency that is lower than y C The Doppler frequency used in [k,l] is half the search step higher or lower (high v bin / 2); The three PN sequences y recovered according to different Doppler frequencies U [k,l],y C [k,l] and y L [k,l] are cross-correlated with y[k,l] generated by the pseudo-random sequence generator to obtain the cross-correlation result R(y,y U ),R(y,y C ),R(y,y L ), if there is an estimation error, the estimated error δ of the Doppler frequency is obtained according to the lead-lag method v : By comparing R(y,y U ) and R(y,y L ) correlation results, the position of the top of the main peak of the PN code autocorrelation function is calculated, and then the Doppler frequency estimate is corrected after passing through the energy frequency detector of the code based on the pseudo-random sequence. Among them, δ v Represents the correction amount, and the corrected estimate Move to the center of the search unit and output the accurately estimated fractional Doppler value Using the same principle, output an accurate estimate of the fractional delay 7. The method according to claim 1, characterized in that The method further comprises: reconstructing a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, demodulating communication service data and navigation data using the channel matrix, and obtaining navigation message information of the captured satellite. The channel matrix G is reconstructed according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and channel equalization is performed according to the channel matrix G and the minimum mean square error criterion to recover the delay-Doppler domain conduction fusion signal: in: is the noise variance, I MN It is a unit array; The delay-Doppler domain navigation and navigation fusion signal is subjected to BPSK / QPSK demapping and channel decoding to obtain the navigation message information of the captured satellite.

8. The method according to claim 1, characterized in that Doppler positioning is performed using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning, including: Assume the satellite position is Speed The satellite transmission frequency is f s , the receiver location is Speed The receiving frequency of the measuring station is f r , the Doppler frequency is Consider the receiver clock error δf r When the frequency measurement error εf is equal to the frequency measurement error εf, the instantaneous Doppler observation equation of the station is calculated as in, is the three-dimensional coordinates and clock error of the measuring station, and the initial estimated values ​​of the target position and clock error are After Taylor expansion and linearization of the observation equation, for the observed quantities at n moments, the least squares form of Doppler positioning is as follows: Where G is the transfer matrix, ∈ is the error vector, k is the number of iterations, Δf is the difference matrix between the Doppler observation and the estimated value, and the calculated receiver position change is Update later The value of gets the rough estimate of the receiver position 9. A 6G communication and guidance signal fusion device for air-ground integration, characterized in that: The device comprises: A communication and guidance signal generation module is used to obtain navigation data and communication service data at the transmitting end and generate a pseudo-random sequence; after performing channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data, the pseudo-random sequence is input into the delay-Doppler domain grid based on OTFS to generate a communication and guidance fusion signal; A communication and conduction signal sending module is used to modulate the communication and conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, and perform parallel-serial conversion to obtain the time-domain communication and conduction fusion signal and then send it using an antenna; The satellite capture module is used to generate a pseudo-random sequence identical to that of the transmitting end at the receiving end, perform parallel-to-serial conversion to generate a time domain sequence, perform correlation operation on the time domain sequence and the received time domain conduction fusion signal, and quickly capture the satellite at the point where the correlation value is maximum; after capturing the satellite, perform serial-to-parallel conversion, Wigner transformation and SFFT transformation on the received time domain conduction fusion signal, restore it to the delay-Doppler domain grid and perform correlation operation with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay; A channel estimation module is used to reconstruct a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and to demodulate communication service data and navigation data using the channel matrix to obtain navigation message information of the captured satellite; A data demodulation module is used to track the loop according to the accurately estimated fractional delay, obtain the propagation time of the signal and multiply it by the speed of light to obtain the propagation distance of the signal, and use the propagation distance of the signal as the distance between the satellite and the target receiver, and define it as a pseudorange; The fusion positioning module is used to perform Doppler positioning using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and navigation message information from four satellites is obtained, a Doppler positioning correction value is calculated based on four sets of navigation message information and four sets of pseudoranges; the receiver's rough estimate of positioning is corrected based on the Doppler positioning correction value to achieve 6G communication and guidance signal fusion transmission.

10. A 6G communication and guidance signal fusion system for air-ground integration, characterized in that: The system includes a satellite and a receiver; the satellite is provided with a communication signal generation module and a communication signal transmission module; the receiver is provided with a satellite capture module, a channel estimation module, a data demodulation module and a fusion positioning module; A communication and guidance signal generation module is used to obtain navigation data and communication service data at the transmitting end and generate a pseudo-random sequence; after performing channel coding, BPSK mapping and QPSK mapping on the navigation data and communication service data, the pseudo-random sequence is input into the delay-Doppler domain grid based on OTFS to generate a communication and guidance fusion signal; A communication and conduction signal sending module is used to modulate the communication and conduction fusion signal from the delay-Doppler domain to the delay-time domain according to the symplectic inverse Fourier transform and the Heisenberg transform, and perform parallel-serial conversion to obtain the time-domain communication and conduction fusion signal and then send it using an antenna; The satellite capture module is used to generate a pseudo-random sequence identical to that of the transmitting end at the receiving end, perform parallel-to-serial conversion to generate a time domain sequence, perform correlation operation on the time domain sequence and the received time domain conduction fusion signal, and quickly capture the satellite at the point where the correlation value is maximum; after capturing the satellite, perform serial-to-parallel conversion, Wigner transformation and SFFT transformation on the received time domain conduction fusion signal, restore it to the delay-Doppler domain grid and perform correlation operation with the pseudo-random sequence to obtain an accurately estimated fractional Doppler value and an accurately estimated fractional delay; A channel estimation module is used to reconstruct a channel matrix according to the accurately estimated fractional Doppler value and the accurately estimated fractional delay, and to demodulate communication service data and navigation data using the channel matrix to obtain navigation message information of the captured satellite; A data demodulation module is used to track the loop according to the accurately estimated fractional delay, obtain the propagation time of the signal and multiply it by the speed of light to obtain the propagation distance of the signal, and use the propagation distance of the signal as the distance between the satellite and the target receiver, and define it as a pseudorange; The fusion positioning module is used to perform Doppler positioning using fractional Doppler values ​​and satellite information to obtain a rough estimate of the receiver's positioning; when at least four satellites are accumulated and navigation message information from four satellites is obtained, a Doppler positioning correction value is calculated based on four sets of navigation message information and four sets of pseudoranges; the receiver's rough estimate of positioning is corrected based on the Doppler positioning correction value to achieve 6G communication and guidance signal fusion transmission.

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