Space gravitational wave detection inter-satellite ranging and communication modulation method and device

Abstract

The application provides a space gravitational wave detection inter-satellite ranging and communication modulation method and device. When inter-satellite ranging and communication is performed for space gravitational wave detection, communication data can be generated according to a preset communication rate, a pseudo code sequence can be generated according to a preset pseudo code rate, and the communication data and the pseudo code sequence are directly spread spectrum modulated to obtain communication ranging code. Then, the modulation index of the communication ranging code can be determined, and the communication ranging code is low-depth phase modulated according to the modulation index to obtain a modulation signal. The modulation signal can be transmitted through a channel, and inter-satellite communication data and absolute distance can be obtained by demodulating and despreading the transmitted modulation signal. The application uses modulation index to modulate the signal when space gravitational wave detection is implemented, so that the power of inter-satellite communication and absolute distance measurement can be realized with smaller power, and inter-satellite communication transmission and absolute distance measurement can be realized.

Description

Technical Field

[0001] This application relates to the field of space gravitational wave detection technology, and in particular to a method and apparatus for inter-satellite ranging and communication modulation for space gravitational wave detection. Background Technology

[0002] In the field of space gravitational wave detection, to achieve the scientific measurement of gravitational wave signals, an equilateral triangle satellite formation can be established, and inter-satellite data detection technology can be applied to measure the minute displacement changes between test masses caused by space gravitational waves. Then, through data processing, space gravitational wave data can be retrieved.

[0003] Inter-satellite data detection technology involves fields such as gravitational wave detection and laser communication technology, which are quite different from laser communication satellites whose main mission is to achieve high capacity and high speed. The laser links formed in inter-satellite data detection technology need to realize inter-satellite ranging and communication transmission at the same time. However, existing ranging and communication methods do not consider the impact on space gravitational wave detection, making it difficult to achieve ranging and communication at the same time as space gravitational wave detection. Summary of the Invention

[0004] The purpose of this application is to at least address one of the aforementioned technical deficiencies, particularly the technical deficiency in existing ranging and communication methods that do not consider the impact of space gravitational wave detection, making it difficult to achieve ranging and communication power simultaneously with space gravitational wave detection.

[0005] This application provides a method for inter-satellite ranging and communication modulation for space gravitational wave detection, the method comprising:

[0006] When detecting gravitational waves in space, communication data is generated according to a preset communication rate, and a pseudocode sequence is generated according to a preset pseudocode rate. The communication data and the pseudocode sequence are then directly spread spectrum modulated to obtain a communication ranging code.

[0007] The modulation index of the communication ranging code is determined, and the communication ranging code is subjected to low-depth phase modulation according to the modulation index to obtain a modulated signal;

[0008] The modulated signal is transmitted through the channel, and the transmitted modulated signal is demodulated and despread to obtain inter-satellite communication data and absolute distance.

[0009] Optionally, the step of performing direct spread spectrum modulation on the communication data and the pseudocode sequence to obtain the communication ranging code includes:

[0010] The communication data is digitally encoded to obtain a communication data sequence, the length of which is proportional to the length of the pseudocode sequence. The multiple relationship; where N is greater than or equal to 1;

[0011] By XORing each character of the communication data sequence with each character of the pseudocode sequence, a communication ranging code is obtained.

[0012] Optionally, determining the modulation index of the communication ranging code includes:

[0013] Acquire multiple sets of modulation data obtained in advance for space gravitational wave detection;

[0014] Determine the correspondence between the power percentage and the modulation index in each group of modulation data, and draw a modulation relationship diagram between the power percentage and the modulation index based on each correspondence.

[0015] The modulation index of the communication ranging code is determined from the modulation relationship diagram based on the preset power ratio.

[0016] Optionally, the modulation data includes a modulation signal and a communication ranging code corresponding to the modulation signal; the modulation signal includes a main carrier and a communication ranging signal.

[0017] Determining the correspondence between the power percentage and the modulation index in each group of modulation data includes:

[0018] A preset signal model is used to perform data analysis on each modulated signal and the corresponding communication ranging code to obtain the modulation index of the communication ranging code in each modulated data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier.

[0019] Calculate the power ratio of the communication ranging signal to the main carrier in each modulation data, and establish the correspondence between the power ratio and the modulation index.

[0020] Optionally, the step of performing phase modulation on the communication ranging code according to the modulation index to obtain a modulated signal includes:

[0021] The communication ranging code and the modulation index are input into a direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer.

[0022] The sinusoidal digital sequence is converted into an analog signal by a digital-to-analog converter, and the analog signal is then low-pass filtered to obtain a modulated signal.

[0023] Optionally, the direct digital synthesizer includes a frequency register, a phase accumulator, a phase modulator, and a sine lookup table memory;

[0024] The step of inputting the communication ranging code and the modulation index into a direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer includes:

[0025] The frequency control word pre-stored in the frequency register is converted into a digital signal, and the digital signal is transmitted to the phase accumulator;

[0026] The phase information in the digital signal is extracted using the phase accumulator, and the phase information is accumulated to obtain the current phase angle.

[0027] The communication ranging code, the modulation index, and the current phase angle are input into the phase modulator, and the phase modulator is used to perform phase modulation on the communication ranging code according to the modulation index and the current phase angle;

[0028] The modulated communication ranging code is input into the sine lookup table memory for phase conversion, and a sine digital sequence is output.

[0029] Optionally, the demodulation and despreading of the transmitted modulated signal to obtain inter-satellite communication data and absolute distance includes:

[0030] The transmitted modulated signal is demodulated using a phase meter, and pseudo-random code information is extracted from the demodulated modulated signal using a delay phase-locked loop. The signal is then despread to obtain inter-satellite communication data and absolute distance.

[0031] This application also provides a space-based gravitational wave detection inter-satellite ranging and communication modulation device, comprising:

[0032] The communication ranging code generation module is used to generate communication data according to a preset communication rate and generate a pseudo code sequence according to a preset pseudo code rate when detecting gravitational waves in space, and to perform direct spread spectrum modulation on the communication data and the pseudo code sequence to obtain the communication ranging code.

[0033] A signal modulation module is used to determine the modulation index of the communication ranging code and perform low-depth phase modulation on the communication ranging code according to the modulation index to obtain a modulated signal.

[0034] The signal demodulation and despreading module is used to transmit the modulated signal through the channel and demodulate and despread the transmitted modulated signal to obtain inter-satellite communication data and absolute distance.

[0035] This application also provides a storage medium storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the space gravitational wave detection inter-satellite ranging and communication modulation method as described in any of the above embodiments.

[0036] This application also provides a computer device, including: one or more processors, and memory;

[0037] The memory stores computer-readable instructions, which, when executed by the one or more processors, perform the steps of the space gravitational wave detection inter-satellite ranging and communication modulation method as described in any of the above embodiments.

[0038] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0039] This application provides a method and apparatus for inter-satellite ranging and communication modulation for space gravitational wave detection. When performing inter-satellite ranging and communication for space gravitational wave detection, communication data and a pseudo-code sequence are first generated according to a preset communication rate and a preset pseudo-code rate, respectively. The communication data and pseudo-code sequence are then directly spread-spectrum modulated to obtain a ranging code. This ranging code, as a special pseudo-code sequence, possesses excellent autocorrelation and cross-correlation characteristics, enabling precise distance measurement and positioning. After generating the ranging code, its modulation index is determined, and low-depth phase modulation is applied to the ranging code based on the modulation index to obtain a modulated signal. This modulated signal is transmitted to the main carrier to obtain a carrier signal, which can then be modulated onto the main carrier for transmission, enabling inter-satellite distance measurement. Finally, the carrier signal is transmitted through a channel, and the transmitted modulated signal is demodulated and despread to obtain inter-satellite communication data and absolute distance. This application utilizes a modulation index to modulate the signal during space gravitational wave detection, thereby enabling inter-satellite communication and absolute distance measurement with relatively low power, achieving the power required for space communication transmission and inter-satellite absolute distance measurement. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 A schematic flowchart illustrating an inter-satellite ranging and communication modulation method for space gravitational wave detection provided in this application embodiment;

[0042] Figure 2 A flowchart illustrating a method for generating a sinusoidal digital sequence provided in an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the direct digital synthesizer provided in an embodiment of this application;

[0044] Figure 4A schematic diagram of the structure of a space gravitational wave detection inter-satellite ranging and communication modulation device provided in this application embodiment;

[0045] Figure 5 This is a schematic diagram of the internal structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0047] In the field of space gravitational wave detection, to achieve the scientific measurement of gravitational wave signals, an equilateral triangle satellite formation can be established, and inter-satellite data detection technology can be applied to measure the minute displacement changes between test masses caused by space gravitational waves. Then, through data processing, the data of space gravitational waves can be retrieved.

[0048] Inter-satellite data detection technology involves fields such as gravitational wave detection and laser communication technology, which are quite different from laser communication satellites whose main mission is to achieve high capacity and high speed. The laser links formed in inter-satellite data detection technology need to realize inter-satellite ranging and communication transmission at the same time. However, existing ranging and communication methods do not consider the impact on space gravitational wave detection, making it difficult to achieve ranging and communication power at the same time as space gravitational wave detection.

[0049] Based on this, this application proposes the following technical solution, as detailed below:

[0050] In one embodiment, such as Figure 1 As shown, Figure 1 This application provides a flowchart illustrating an inter-satellite ranging and communication modulation method for space gravitational wave detection, as illustrated in an embodiment of this application. The application also provides a specific method for inter-satellite ranging and communication modulation for space gravitational wave detection, comprising the following steps:

[0051] S110: When detecting gravitational waves in space, communication data is generated according to a preset communication rate, and a pseudo-code sequence is generated according to a preset pseudo-code rate. The communication data and pseudo-code sequence are then directly spread spectrum modulated to obtain a communication ranging code.

[0052] In this step, when targeting space gravitational wave detection, the signal modulation system can randomly generate communication data according to a preset communication rate. This communication data can be used to transmit data obtained during the space gravitational wave detection process. It can also generate a pseudo-code sequence according to a preset pseudo-code rate to measure the absolute distance between two satellites. Finally, the signal modulation system can directly spread spectrum modulate the communication data and the pseudo-code sequence to obtain the communication ranging code.

[0053] Direct spread spectrum modulation (DSSM) is a digital modulation technique mainly used in wireless communication, radar, positioning, and navigation. Its basic principle is to directly multiply the digital signal to be transmitted with a high-frequency spreading code, thereby expanding the bandwidth of the signal to the entire bandwidth of the spreading code and realizing the spread spectrum transmission of the signal. Therefore, this application uses DSM to generate the communication ranging code.

[0054] It should be noted that the signal modulation system includes a clock module, a data module, a pseudocode module, and a direct sequence spread spectrum module. This application utilizes each module to perform its corresponding function to realize a scheme for inter-satellite ranging and communication modulation for space gravitational wave detection. Specifically, the clock module provides clock frequencies to the other modules to ensure the orderly operation of each module in the signal modulation system; the data module randomly generates communication data; the pseudocode module generates pseudocode sequences; and the direct sequence spread spectrum module performs direct spread spectrum modulation on the communication data and the pseudocode sequences.

[0055] Specifically, the pseudocode module pre-stores a preset pseudocode rate. To improve the accuracy of inter-satellite absolute distance measurements, the preset pseudocode rate can be set considering the autocorrelation, cross-correlation, length, and quantity of the pseudocode. When the pseudocode module receives the clock frequency sent by the clock module, it can generate a pseudocode sequence according to the preset pseudocode rate. The data module pre-stores a preset communication rate, which is mainly set based on the preset pseudocode rate to improve the correlation between the preset pseudocode rate and the preset communication rate. When the data module receives the clock frequency sent by the clock module, it can generate communication data according to the preset communication rate.

[0056] For example, if the preset pseudocode rate stored in the pseudocode module is 3.125MHz, then when setting the preset communication rate of the data module, the preset communication rate can be calculated using the spreading factor. If the spreading factor selected in this application is 64, then the preset communication rate can be 48.8kHz. The specific calculation process is as follows:

[0057]

[0058] In the formula, Indicates the preset communication rate; Indicates the preset pseudocode rate; It represents the spreading factor of the signal modulation system.

[0059] S120: Determine the modulation index of the communication ranging code, and perform phase modulation on the communication ranging code according to the modulation index to obtain the modulated signal.

[0060] In this step, after obtaining the communication ranging code through step S110, the signal modulation system can determine the modulation index of the communication ranging code according to the actual needs of inter-satellite communication and distance measurement. Then, the communication ranging code can be phase-modulated according to the modulation index to obtain a modulated signal, which is used as a signal for detection in space gravitational wave detection.

[0061] The modulation index describes the power distribution between the modulating signal and the main carrier during inter-satellite data detection, characterizing the strength and degree of modulation of the modulated signal. During phase modulation, the magnitude of the modulation index determines the power distribution of the modulated signal. If the modulation index is too large, the available power for inter-satellite data detection will be too small, affecting the normal operation of inter-satellite data measurements and compromising the accuracy of space gravitational wave detection data. Conversely, if the modulation index is too small, it will affect the normal operation of the modulated signal, meaning that the pseudocode sequence ranging of the modulated signal cannot be synchronized, leading to the inability to despread communication data.

[0062] For example, in order not to affect the accuracy of inter-satellite data measurements for space gravitational wave detection, this application can design the power used for phase modulation of the communication ranging code to account for only 1% of the total power, and the modulation index corresponding to this power percentage is 0.1 rad.

[0063] It should be noted that when modulating the signal, the modulation signal obtained after transmitting the communication ranging code to the main carrier according to the modulation index can be used for inter-satellite data detection. This allows the main carrier to measure the absolute distance between satellites using the communication ranging code while detecting space communication data, thereby realizing inter-satellite ranging and inter-satellite communication data detection simultaneously with space gravitational wave detection and improving the accuracy of inter-satellite ranging.

[0064] Furthermore, the modulation process of the modulation signal in this application can be implemented on an FPGA (Field-Programmable Gate Array). An FPGA is a programmable logic device that consists of a large number of programmable logic elements (LEs) and programmable interconnects. It implements the functions of various digital circuits through programming and has the advantages of high flexibility, strong reconfigurability, high logic density, and good timing performance.

[0065] S130: Transmit the modulated signal through the channel, and demodulate and despread the transmitted modulated signal to obtain inter-satellite communication data and absolute distance.

[0066] In this step, after generating the modulation signal in step S120, the signal modulation system can transmit the modulation signal so that the modulation signal can be transmitted through the channel during space transmission. After receiving the modulation signal, the signal modulation system can demodulate and despread the received modulation signal to obtain inter-satellite communication data and absolute distance.

[0067] It should be noted that the signal modulation system may also include a signal receiver, which, as the receiving end, receives the modulated signal transmitted by the signal modulation system through the channel.

[0068] In the above embodiments, when performing inter-satellite ranging and communication for space gravitational wave detection, communication data and a pseudo-code sequence can be generated according to a preset communication rate and a preset pseudo-code rate, respectively. The communication data and pseudo-code sequence are then directly spread-spectrum modulated to obtain a communication ranging code. This communication ranging code, as a special pseudo-code sequence, possesses good autocorrelation and cross-correlation characteristics, which can be used to achieve accurate distance measurement and positioning. After generating the communication ranging code, its modulation index can be determined, and low-depth phase modulation can be performed on the communication ranging code according to the modulation index to obtain a modulated signal. This modulated signal can then be modulated onto the main carrier to form a modulated signal, which can then be transmitted along with the main carrier to achieve inter-satellite distance measurement using the modulated signal. Finally, the modulated signal can be transmitted through the channel, and the transmitted modulated signal can be analyzed to obtain inter-satellite communication data and absolute distance. This application utilizes the modulation index to modulate the signal during space gravitational wave detection, thereby enabling inter-satellite communication and absolute distance measurement with relatively low power, achieving both space communication transmission and inter-satellite absolute distance measurement.

[0069] In one embodiment, step S110, which involves direct spread spectrum modulation of the communication data and the pseudocode sequence to obtain a communication ranging code, may include:

[0070] S111: Digitally encode the communication data to obtain a communication data sequence.

[0071] S112: After XORing each character of the communication data sequence with each character of the pseudocode sequence, the communication ranging code is obtained.

[0072] In this embodiment, after obtaining the communication data and the pseudocode sequence, the signal modulation system can digitally encode the communication data to obtain a communication data sequence. The length of the communication data sequence is approximately equal to the length of the pseudocode sequence. The multiple relationship is such that N is greater than or equal to 1. Therefore, each character of the communication data sequence can be XORed with each character of the pseudocode sequence to obtain the communication ranging code.

[0073] The XOR operation is a logical operator. In the XOR operation, if the corresponding bits of the two operands are different, the result is 1; if the corresponding bits of the two operands are the same, the result is 0.

[0074] Understandably, in direct spread spectrum modulation, performing an XOR operation on the communication data sequence and the pseudocode sequence can extend the bandwidth of the communication data to the bandwidth of the pseudocode sequence, thereby realizing spread spectrum transmission of the data. Furthermore, as a pseudo-random code sequence, the pseudocode sequence has a high degree of randomness and unpredictability. Therefore, by performing an XOR operation on the communication data sequence and the pseudocode sequence, the security of the communication ranging code can be enhanced and signal interference can be prevented.

[0075] In one embodiment, determining the modulation index of the communication ranging code in step S120 may include:

[0076] S121: Acquire modulation data obtained in advance when acquiring multiple sets of space-oriented gravitational waves.

[0077] S122: Determine the correspondence between the power percentage and the modulation index in each group of modulation data, and draw the modulation relationship diagram between the power percentage and the modulation index based on each correspondence.

[0078] S123: Determine the modulation index of the communication ranging code from the modulation relationship diagram according to the preset power ratio.

[0079] In this embodiment, the signal modulation system can determine the modulation index of the communication ranging code from the pre-stored modulation relationship diagram based on the preset power ratio. In addition, when it is necessary to update the modulation relationship diagram, the signal modulation system can first obtain the modulation data facing space gravitational waves in advance and determine the correspondence between the power ratio and the modulation index in each set of modulation data. Thus, the modulation relationship diagram between the power ratio and the modulation index can be drawn based on each correspondence.

[0080] Specifically, when plotting the modulation relationship diagram, the signal modulation system can read multiple sets of modulation data from different periods. It can then determine the power proportions allocated to the communication ranging code and the main carrier in each set of modulation data, as well as the modulation index of the communication ranging code, thereby deriving the correspondence between the power proportions and the modulation index. After obtaining the power proportions corresponding to the range of modulation index values, a modulation relationship diagram between the power proportions and the modulation index can be plotted based on these correspondences. This plotted modulation relationship diagram is then stored in the signal modulation system as an important basis for selecting the modulation index of the communication ranging code.

[0081] In one embodiment, the modulation data in step S122 includes a modulation signal and a communication ranging code corresponding to the modulation signal; wherein, determining the correspondence between the power ratio and the modulation index in each group of modulation data may include:

[0082] S1221: Using a preset signal model, perform data analysis on each modulation signal and the corresponding communication test code to obtain the modulation index of the communication ranging code in each modulation data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier.

[0083] S1222: Calculate the power ratio of the communication ranging signal to the main carrier in each modulation data, and establish the correspondence between the power ratio and the modulation index.

[0084] In this embodiment, when determining the correspondence between the power ratio and the modulation index in each set of modulation data, for each set of modulation data, the signal modulation system can input the modulation signal and the corresponding communication test code into the preset signal model and obtain the demodulated data output by the preset signal model. Then, it can read the modulation index of the communication ranging code in the demodulated data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier. Then, it can calculate the power ratio of the communication ranging signal and the main carrier in each set of modulation data and establish the correspondence between the power ratio and the modulation index.

[0085] Specifically, the calculation formula for the demodulated data of the preset signal model is as follows:

[0086]

[0087] In the formula, Indicates the carrier number; Indicates the laser heterodyne efficiency; This indicates the local carrier power of the signal receiver; This indicates the carrier power received by the signal receiver; Indicates the frequency of the modulating signal; The modulation index represents the ranging code of communication. This represents a bipolar communication ranging code sequence consisting of [-1, 1], whose pulse shape is periodic. Provided.

[0088] Among them, the power allocated to the main carrier during inter-satellite data detection. and the remaining power used for communication ranging signals The calculation process is as follows:

[0089]

[0090]

[0091] From the above formula, the relationship between the modulation index and the power ratio can be derived as follows:

[0092]

[0093] In one embodiment, step S120, which involves performing low-depth phase modulation on the communication ranging code based on the modulation index to obtain a modulated signal, may include:

[0094] S124: Input the communication ranging code and modulation index into the direct digital synthesizer to obtain the sinusoidal digital sequence output by the direct digital synthesizer.

[0095] S125: Converts a sinusoidal digital sequence into an analog signal using a digital-to-analog converter, and then uses a low-pass filter to perform low-pass filtering on the analog signal to obtain a modulated signal.

[0096] In this embodiment, the signal modulation system may further include a direct digital synthesizer, a digital-to-analog converter, and a low-pass filter. When performing phase modulation on the communication ranging code, the communication ranging code and the modulation index can be input into the direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer. Then, the sinusoidal digital sequence can be converted into an analog signal by the digital-to-analog converter, and the analog signal can be low-pass filtered by the low-pass filter to obtain the modulated signal.

[0097] Among them, a Direct Digital Synthesizer (DDS) refers to a high-precision, high-stability signal source based on digital signal processing technology. It can generate signals with various programmable frequencies and phases, and has advantages such as high precision, flexible modulation, variable frequency, and continuously adjustable phase. A Digital-to-Analog Converter (DAC) is a circuit or device that converts digital signals into analog signals. It can convert discrete values ​​of digital signals into continuous analog signals, realizing digital-to-analog signal conversion. It features high resolution, fast conversion speed, good stability, low power consumption, and high integration. A Low-Pass Filter (LPF) is a filter that can filter high-frequency signals and transmit only low-frequency signals. It can reduce or eliminate high-frequency components in a signal while retaining low-frequency components, thereby achieving frequency selection and adjustment. It has advantages such as frequency selection and adjustment, noise and interference suppression, and improved signal quality and accuracy.

[0098] Specifically, a digital-to-analog converter (DAC) can consist of a digital signal input terminal, a digital signal processing module, a digital-to-analog conversion module, and an analog signal output terminal. The digital signal input terminal receives the digital signal to be converted; the digital signal processing module processes and modulates the digital signal; the digital-to-analog conversion module converts the digital signal into an analog signal; and the analog signal output terminal outputs the converted analog signal. When the DAC receives a sinusoidal digital sequence, it can map the discrete values ​​of the sinusoidal digital sequence to a continuous analog signal range, forming an analog voltage value. By controlling the clock frequency, the quantized sinusoidal digital sequence is output sequentially at certain time intervals, forming a continuous analog signal waveform.

[0099] Furthermore, a low-pass filter can receive analog signals output from a digital-to-analog converter. When the analog signal passes through the low-pass filter, high-frequency components are suppressed or eliminated, leaving only low-frequency components to pass through, thereby achieving frequency selection and adjustment of the signal. Since the passband cutoff frequency and stopband attenuation of the low-pass filter determine the filter's frequency response and filtering effect, a suitable low-pass filter can be selected according to specific application requirements and analog signal characteristics in this application.

[0100] In one embodiment, such as Figure 2 As shown, Figure 2 A flowchart illustrating a method for generating a sinusoidal digital sequence provided in an embodiment of this application; Figure 2 In step S124, the communication ranging code and modulation index are input into the direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer, which may include:

[0101] S1241: Converts the pre-stored frequency control word in the frequency register into a digital signal and transmits the digital signal to the phase accumulator.

[0102] S1242: Use a phase accumulator to extract phase information from the digital signal and perform phase accumulation on the phase information to obtain the current phase angle.

[0103] S1243: Input the communication ranging code, modulation index and current phase angle into the phase modulator, and use the phase modulator to perform phase modulation on the communication ranging code according to the modulation index and current phase angle.

[0104] S1244: Input the modulated communication ranging code into the sine lookup table memory for phase conversion, and output the sine digital sequence.

[0105] In this embodiment, the direct digital synthesizer can be composed of a frequency register, a phase accumulator, a phase modulator, and a sine lookup table memory. After the phase modulator receives the communication ranging code and the modulation index, the frequency register can convert the pre-stored frequency control word into a digital signal and transmit the digital signal to the phase accumulator. Then, the phase accumulator can extract the phase information from the digital signal and perform a phase accumulation operation on the phase information to obtain the current phase angle. The current phase angle is then input to the phase modulator so that the phase modulator can perform phase modulation on the communication ranging code according to the modulation index and the current phase angle. Finally, the sine lookup table memory can perform phase conversion on the modulated communication ranging code and output a sine digital sequence.

[0106] Indicatively, such as Figure 3 As shown, Figure 3 This is a schematic diagram of the direct digital synthesizer provided in an embodiment of this application; Figure 3 In this circuit, the phase modulator consists of a switching circuit, a register, and a phase modulation section. A sine lookup table memory stores the sine lookup table. When the communication ranging code and modulation index are input as control signals to the switching circuit, under the control of the phase control word, the frequency register converts the frequency control word K into a digital signal and sends it as input to the phase accumulator, which consists of a full adder and a phase accumulator register. Under the control of the clock frequency, the frequency control word K is added to the data output from the phase accumulator register of the previous clock cycle in each clock cycle, and the phase accumulator register is updated, thus completing one phase accumulation operation. An adder exists between the phase accumulator and the sine lookup table, allowing the modulation index to be added to the output of the phase accumulator. The resulting phase information is then used as the lookup table address to periodically query the sine lookup table to retrieve the sampled amplitude of the waveform from memory, achieving phase-to-amplitude conversion. The output data is a sine digital sequence, which can finally be passed through a digital-to-analog converter and a low-pass filter to obtain the modulated signal.

[0107] In one embodiment, step S130, which involves demodulating and despreading the transmitted modulated signal to obtain inter-satellite communication data and absolute distance, may include:

[0108] S131: The phase meter is used to demodulate the transmitted modulated signal, and a delay phase-locked loop is used to extract pseudo-random code information from the demodulated modulated signal, and despread it to obtain inter-satellite communication data and absolute distance.

[0109] In this embodiment, the signal modulation system can transmit a modulated signal to the signal receiver through a signal transmitter. After the signal receiver receives the modulated signal, it uses a phase meter to demodulate the modulated signal. Then, a delay phase-locked loop can be used to extract pseudo-random code information from the demodulated modulated signal and despread it to obtain inter-satellite communication data and absolute distance.

[0110] Specifically, the phase meter can receive the modulated signal, mix it with a signal of the same frequency generated by a local oscillator to obtain an intermediate frequency (IF) signal, and then measure the phase of the IF signal to restore the modulated signal, thus achieving demodulation. Next, the demodulated modulated signal can be input into a delay phase-locked loop (DLL), and a pseudo-random code can be used as a reference signal to synchronize the signal output by the VCO (Voltage Controlled Oscillator) with the reference signal. Finally, the synchronized signal can be despread to obtain inter-satellite communication data. Using the pseudorange positioning principle, the distance between the signal receiver and the satellite can be calculated using the despread inter-satellite communication data and the satellite's position information, thus obtaining the absolute distance.

[0111] The following describes the space gravitational wave detection inter-satellite ranging and communication modulation device provided in the embodiments of this application. The space gravitational wave detection inter-satellite ranging and communication modulation device described below can be referred to in correspondence with the space gravitational wave detection inter-satellite ranging and communication modulation method described above.

[0112] In one embodiment, such as Figure 4 As shown, Figure 4 This application provides a schematic diagram of the structure of an inter-satellite ranging and communication modulation device for space gravitational wave detection, as provided in an embodiment of the present application. The present application also provides an inter-satellite ranging and communication modulation device for space gravitational wave detection, including a communication ranging code generation module 210, a signal modulation module 220, and a signal demodulation and dilatation module 230, specifically comprising the following:

[0113] The communication ranging code generation module 210 is used to generate communication data according to a preset communication rate and generate a pseudo code sequence according to a preset pseudo code rate when conducting space-based gravitational wave detection, and to perform direct spread spectrum modulation on the communication data and pseudo code sequence to obtain the communication ranging code.

[0114] The signal modulation module 220 is used to determine the modulation index of the communication ranging code and perform low-depth phase modulation on the communication ranging code according to the modulation index to obtain the modulated signal.

[0115] The signal demodulation and despreading module 230 is used to transmit the modulated signal through the channel and demodulate and despread the transmitted modulated signal to obtain inter-satellite communication data and absolute distance.

[0116] In the above embodiments, when performing inter-satellite ranging and communication for space gravitational wave detection, communication data and a pseudo-code sequence can be generated according to a preset communication rate and a preset pseudo-code rate, respectively. The communication data and pseudo-code sequence are then directly spread-spectrum modulated to obtain a communication ranging code. This communication ranging code, as a special pseudo-code sequence, possesses good autocorrelation and cross-correlation characteristics, which can be used to achieve accurate distance measurement and positioning. After generating the communication ranging code, its modulation index can be determined, and phase modulation can be applied to the communication ranging code according to the modulation index to obtain a modulated signal. This modulated signal can then be modulated onto the main carrier to form a modulated signal, which can then be transmitted along with the main carrier to achieve inter-satellite distance measurement using the modulated signal. Finally, the modulated signal can be transmitted through the channel, and the transmitted modulated signal can be analyzed to obtain inter-satellite communication data and absolute distance. This application utilizes the modulation index to modulate the signal during space gravitational wave detection, thereby enabling inter-satellite communication and absolute distance measurement with relatively low power, achieving both space communication transmission and inter-satellite absolute distance measurement.

[0117] In one embodiment, the communication ranging code generation module 210 may include:

[0118] The communication data encoding submodule is used to digitally encode the communication data to obtain a communication data sequence.

[0119] The XOR operation submodule is used to perform an XOR operation on each character of the communication data sequence and each character of the pseudocode sequence to obtain the communication ranging code.

[0120] In one embodiment, the signal modulation module 220 may include:

[0121] The historical data acquisition submodule is used to acquire multiple sets of modulation data obtained in advance for space gravitational wave detection.

[0122] The relationship graph drawing submodule is used to determine the correspondence between the power proportion and the modulation index in each group of modulation data, and to draw the modulation relationship graph between the power proportion and the modulation index based on each correspondence.

[0123] The modulation index determination submodule is used to determine the modulation index of the communication ranging code from the modulation relationship diagram based on a preset power ratio.

[0124] In one embodiment, the relationship diagram drawing submodule may include:

[0125] The data analysis unit is used to perform data analysis on each modulated signal and the corresponding communication ranging code using a preset signal model, to obtain the modulation index of the communication ranging code in each modulated data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier.

[0126] The correspondence establishment unit is used to calculate the power ratio of the communication ranging signal and the main carrier in each modulation data, and to establish the correspondence between the power ratio and the modulation index.

[0127] In one embodiment, the signal modulation module 220 may include:

[0128] The sequence generation submodule is used to input the communication ranging code and modulation index into the direct digital synthesizer to obtain the sinusoidal digital sequence output by the direct digital synthesizer.

[0129] The signal conversion submodule is used to convert a sinusoidal digital sequence into an analog signal using a digital-to-analog converter, and to perform low-pass filtering on the analog signal to obtain a modulated signal.

[0130] In one embodiment, the sequence generation submodule may include:

[0131] The digital signal generation unit is used to convert the frequency control word pre-stored in the frequency register into a digital signal and transmit the digital signal to the phase accumulator.

[0132] The phase accumulation unit is used to extract phase information from the digital signal using a phase accumulator, and to perform phase accumulation operation on the phase information to obtain the current phase angle.

[0133] The phase modulation unit is used to input the communication ranging code, modulation index and current phase angle into the phase modulator, and use the phase modulator to perform phase modulation on the communication ranging code according to the modulation index and the current phase angle.

[0134] The phase conversion unit is used to input the modulated communication ranging code into the sine lookup table memory for phase conversion and output a sine digital sequence.

[0135] In one embodiment, the signal demodulation and despreading module 230 may include:

[0136] The signal demodulation and despreading submodule is used to demodulate the transmitted modulated signal using a phase meter, extract pseudo-random code information from the demodulated modulated signal using a delay phase-locked loop, and despread to obtain inter-satellite communication data and absolute distance.

[0137] In one embodiment, this application also provides a storage medium storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the space gravitational wave modulation method as described in any of the above embodiments.

[0138] In one embodiment, this application also provides a computer device storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the space gravitational wave modulation method as described in any of the above embodiments.

[0139] Indicatively, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the internal structure of a computer device 300 provided in an embodiment of this application. The computer device 300 can be provided as a server. (Refer to...) Figure 5 The computer device 300 includes a processing component 302, which further includes one or more processors, and memory resources represented by memory 301 for storing instructions, such as application programs, that can be executed by the processing component 302. The application programs stored in memory 301 may include one or more modules, each corresponding to a set of instructions. Furthermore, the processing component 302 is configured to execute instructions to perform the space gravitational wave modulation method of any of the above embodiments.

[0140] The computer device 300 may also include a power supply component 303 configured to perform power management of the computer device 300, a wired or wireless network interface 304 configured to connect the computer device 300 to a network, and an input / output (I / O) interface 305. The computer device 300 may operate on an operating system stored in memory 301, such as Windows Server™, Mac OS X™, Unix™, Linux™, Free BSD™, or similar.

[0141] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0142] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0143] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0144] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for inter-satellite ranging and communication modulation for space gravitational wave detection, characterized in that, The method includes: When detecting gravitational waves in space, communication data is generated according to a preset communication rate, and a pseudocode sequence is generated according to a preset pseudocode rate. The communication data and the pseudocode sequence are then directly spread spectrum modulated to obtain a communication ranging code. The modulation index of the communication ranging code is determined, and the communication ranging code is subjected to low-depth phase modulation according to the modulation index to obtain a modulated signal; The modulated signal is transmitted through the channel, and the transmitted modulated signal is demodulated and despread to obtain inter-satellite communication data and absolute distance. The step of determining the modulation index of the communication ranging code includes: Acquire multiple sets of modulation data obtained in advance for space gravitational wave detection; Determine the correspondence between the power percentage and the modulation index in each group of modulation data, and draw a modulation relationship diagram between the power percentage and the modulation index based on each correspondence. The modulation index of the communication ranging code is determined from the modulation relationship diagram based on the preset power ratio; The modulation data includes a modulation signal and a communication ranging code corresponding to the modulation signal; the modulation signal includes a main carrier and a communication ranging code signal. Determining the correspondence between the power percentage and the modulation index in each group of modulation data includes: A preset signal model is used to perform data analysis on each modulated signal and the corresponding communication ranging code to obtain the modulation index of the communication ranging code in each modulated data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier. Calculate the power ratio of the communication ranging signal to the main carrier in each modulation data, and establish the correspondence between the power ratio and the modulation index; The specific calculation formula for the demodulated data of the preset signal model is as follows: In the formula, Indicates the carrier number; Indicates the laser heterodyne efficiency; This indicates the local carrier power of the signal receiver; This indicates the carrier power received by the signal receiver; Indicates the frequency of the modulating signal; The modulation index represents the ranging code used in communication. This represents a bipolar communication ranging code sequence consisting of [-1, 1], whose pulse shape is periodic. Give; Power allocated to the primary carrier during inter-satellite data detection and the remaining power used for communication ranging signals The calculation process is as follows: The relationship between the modulation index and the power ratio derived from the above formula is as follows: 。 2. The inter-satellite ranging and communication modulation method for space gravitational wave detection according to claim 1, characterized in that, The step of performing direct spread spectrum modulation on the communication data and the pseudocode sequence to obtain the communication ranging code includes: The communication data is digitally encoded to obtain a communication data sequence, the length of which is proportional to the length of the pseudocode sequence. The multiple relationship; where N is greater than or equal to 1; By XORing each character of the communication data sequence with each character of the pseudocode sequence, a communication ranging code is obtained.

3. The inter-satellite ranging and communication modulation method for space gravitational wave detection according to claim 1, characterized in that, The step of performing phase modulation on the communication ranging code according to the modulation index to obtain a modulated signal includes: The communication ranging code and the modulation index are input into a direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer. The sinusoidal digital sequence is converted into an analog signal by a digital-to-analog converter, and the analog signal is then low-pass filtered to obtain a modulated signal.

4. The inter-satellite ranging and communication modulation method for space gravitational wave detection according to claim 3, characterized in that, The direct digital synthesizer includes a frequency register, a phase accumulator, a phase modulator, and a sine lookup table memory; The step of inputting the communication ranging code and the modulation index into a direct digital synthesizer to obtain a sinusoidal digital sequence output by the direct digital synthesizer includes: The frequency control word pre-stored in the frequency register is converted into a digital signal, and the digital signal is transmitted to the phase accumulator; The phase information in the digital signal is extracted using the phase accumulator, and the phase information is accumulated to obtain the current phase angle. The communication ranging code, the modulation index, and the current phase angle are input into the phase modulator, and the phase modulator is used to perform phase modulation on the communication ranging code according to the modulation index and the current phase angle; The modulated communication ranging code is input into the sine lookup table memory for phase conversion, and a sine digital sequence is output.

5. The inter-satellite ranging and communication modulation method for space gravitational wave detection according to claim 1, characterized in that, The process of demodulating and despreading the transmitted modulated signal to obtain inter-satellite communication data and absolute distance includes: The phase meter is used to demodulate the transmitted modulated signal, and a delay phase-locked loop is used to extract pseudo-random code information from the demodulated modulated signal. The signal is then despread to obtain inter-satellite communication data and absolute distance.

6. A space gravitational wave detection inter-satellite ranging and communication modulation device, characterized in that, include: The communication ranging code generation module is used to generate communication data according to a preset communication rate and generate a pseudo code sequence according to a preset pseudo code rate when detecting gravitational waves in space, and to perform direct spread spectrum modulation on the communication data and the pseudo code sequence to obtain the communication ranging code. A signal modulation module is used to determine the modulation index of the communication ranging code and perform low-depth phase modulation on the communication ranging code according to the modulation index to obtain a modulated signal; The signal demodulation and despreading module is used to transmit the modulated signal through the channel and demodulate and despread the transmitted modulated signal to obtain inter-satellite communication data and absolute distance. The process of determining the modulation index of the communication ranging code in the signal modulation module includes: Acquire multiple sets of modulation data obtained in advance for space gravitational wave detection; Determine the correspondence between the power percentage and the modulation index in each group of modulation data, and draw a modulation relationship diagram between the power percentage and the modulation index based on each correspondence. The modulation index of the communication ranging code is determined from the modulation relationship diagram based on the preset power ratio; The modulation data includes a modulation signal and a communication ranging code corresponding to the modulation signal; the modulation signal includes a main carrier and a communication ranging code signal. Determining the correspondence between the power percentage and the modulation index in each group of modulation data includes: A preset signal model is used to perform data analysis on each modulated signal and the corresponding communication ranging code to obtain the modulation index of the communication ranging code in each modulated data, as well as the power allocated to the communication ranging signal and the power allocated to the main carrier. Calculate the power ratio of the communication ranging signal to the main carrier in each modulation data, and establish the correspondence between the power ratio and the modulation index; The specific calculation formula for the demodulated data of the preset signal model is as follows: In the formula, Indicates the carrier number; Indicates the laser heterodyne efficiency; This indicates the local carrier power of the signal receiver; This indicates the carrier power received by the signal receiver; Indicates the frequency of the modulating signal; The modulation index represents the ranging code used in communication. This represents a bipolar communication ranging code sequence consisting of [-1, 1], whose pulse shape is periodic. Give; Power allocated to the primary carrier during inter-satellite data detection and the remaining power used for communication ranging signals The calculation process is as follows: The relationship between the modulation index and the power ratio derived from the above formula is as follows: 。 7. A storage medium, characterized in that: The storage medium stores computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the space gravitational wave detection inter-satellite ranging and communication modulation method as described in any one of claims 1 to 5.

8. A computer device, characterized in that, include: One or more processors, and memory; The memory stores computer-readable instructions, which, when executed by the one or more processors, perform the steps of the space gravitational wave detection inter-satellite ranging and communication modulation method as described in any one of claims 1 to 5.

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