Space-based Internet of Things communication frequency hopping processing method, device, equipment and storage medium

Abstract

The present application relates to a method, device, equipment and storage medium for frequency hopping processing of space-based Internet of Things communication. The first information bit stream is obtained by acquiring the frequency hopping signal of the ground terminal and performing PSK coherent demodulation; the first information bit stream is convolutionally decoded to obtain the number of frequency hopping points and the frequency hopping sequence number of the ground terminal, and the frequency hopping pattern of the ground terminal is calculated to obtain the frequency hopping table; the theoretical frequency band of the current frequency band signal is obtained through the frequency hopping table, and the Doppler shift is calculated; the theoretical frequency of the next frequency band signal is obtained according to the frequency hopping table, and the tracking frequency of the next frequency band is obtained, and the PSK coherent demodulation is performed with the tracking frequency of the next frequency band as the starting frequency to obtain the second information bit stream; it is determined whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points. If not, the second information bit stream is processed to obtain the information bit stream of the frequency hopping signal. The use of this method can realize a many-to-one communication mode and improve the channel receiving capacity.

Description

Technical Field

[0001] The present application relates to the field of satellite communication technology, and in particular to a method, device, equipment and storage medium for frequency hopping processing in space-based Internet of Things communications. Background Art

[0002] Due to geographical restrictions such as islands, forests, deserts, and oceans, there are a large number of blind spots in the construction of traditional land communication base stations. According to statistics, only 20% of the land area and 5% of the ocean area in the world are covered by the signals of land communication base stations. With the growing demand for IoT coverage, space-based IoT communication technology has emerged. The so-called space-based IoT is to launch several satellites into space and use satellites as base stations to form a launch center in the universe to provide IoT services to users on the ground.

[0003] However, space-based IoT communications belong to the category of narrowband communications, with low information transmission rates, but high requirements for signal reception sensitivity. In existing space-based IoT communications, spread spectrum communications are often used. Spread spectrum communications have good anti-interference performance, but low unit spectrum utilization and limited code division multiple access capabilities, resulting in limited ability to simultaneously receive ground terminals. Summary of the invention

[0004] Based on this, it is necessary to provide a method, device, equipment and storage medium for space-based Internet of Things communication frequency hopping processing that can improve channel receiving capacity and realize many-to-one communication in response to the above technical problems.

[0005] A frequency hopping processing method for space-based Internet of Things communication, comprising:

[0006] Acquire a frequency hopping signal of a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream;

[0007] Performing convolution decoding on the first information bit stream to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, calculating a ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtaining a frequency hopping table;

[0008] Acquire the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculate the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal;

[0009] Obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtain a second information bit stream;

[0010] It is determined whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies; if not, the second information bit stream is processed to obtain an information bit stream of the frequency hopping signal.

[0011] In one of the embodiments, the air interface protocol frame format in the space-based Internet of Things communication includes a synchronization header, a physical layer frame header, a physical layer frame header CRC, a physical layer payload and a physical layer payload CRC; the physical layer frame header includes a ground terminal frequency hopping sequence number.

[0012] In one embodiment, obtaining a frequency hopping signal of a ground terminal and performing PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream includes:

[0013] The satellite receiver captures the frequency hopping signal and sends the frequency hopping signal to the frequency hopping signal processing module for processing to obtain the current signal frequency;

[0014] According to the current signal frequency, PSK coherent demodulation is performed on the data stream collected by the AD converter to obtain a first information bit stream.

[0015] In one of the embodiments, the satellite-borne receiver uses FFT signal processing when capturing the frequency hopping signal.

[0016] In one embodiment, the first information bit stream is convolutionally decoded to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, and a ground terminal frequency hopping pattern is calculated according to the ground terminal frequency hopping sequence number to obtain a frequency hopping table, including:

[0017] A frame synchronization word is found according to the first information bit stream, and the first information bit stream is convolutionally decoded according to the frame synchronization word to obtain a physical frame header, and the number of frequency hopping points is obtained by calculation, and the ground terminal frequency hopping pattern is calculated according to the ground terminal frequency hopping sequence number in the physical frame header to obtain a frequency hopping table.

[0018] In one embodiment, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal includes:

[0019] According to the frequency hopping table, the theoretical frequency band f(i) of the current frequency band signal is obtained, and the last moment frequency tracked by PSK coherent demodulation at the last moment of the current signal frequency band is set as Ff(i). According to the theoretical frequency band f(i) of the current frequency band signal and the last moment frequency Ff(i), the Doppler frequency shift Fd(i) = Ff(i) - f(i) is obtained.

[0020] In one embodiment, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies, and if not, processing the second information bit stream to obtain an information bit stream of the frequency hopping signal, including:

[0021] It is determined whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points. If not, the second information bit stream is sequentially deinterleaved, convolutionally decoded and descrambled to obtain an information bit stream of the physical payload frame data.

[0022] A space-based Internet of Things communication frequency hopping processing device, comprising:

[0023] A signal acquisition module, used to acquire a frequency hopping signal of a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream;

[0024] A convolution decoding module, configured to perform convolution decoding on the first information bit stream to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, calculate a ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtain a frequency hopping table;

[0025] A Doppler frequency shift calculation module, which obtains the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculates the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal;

[0026] A tracking frequency calculation module is used to obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, and perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency to obtain a second information bit stream;

[0027] The information bit stream processing module determines whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies. If not, the second information bit stream is processed to obtain an information bit stream of the frequency hopping signal.

[0028] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0029] Step 102, acquiring a frequency hopping signal of a ground terminal, and performing PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream;

[0030] Step 104, performing convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the frequency hopping sequence number of the ground terminal, calculating the frequency hopping pattern of the ground terminal according to the frequency hopping sequence number of the ground terminal, and obtaining a frequency hopping table;

[0031] Step 106, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal;

[0032] Step 108, obtaining the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtaining the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, performing PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtaining a second information bit stream;

[0033] Step 110, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies; if not, processing the second information bit stream to obtain an information bit stream of a frequency hopping signal.

[0034] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

[0035] Step 102, acquiring a frequency hopping signal of a ground terminal, and performing PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream;

[0036] Step 104, performing convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the frequency hopping sequence number of the ground terminal, calculating the frequency hopping pattern of the ground terminal according to the frequency hopping sequence number of the ground terminal, and obtaining a frequency hopping table;

[0037] Step 106, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal;

[0038] Step 108, obtaining the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtaining the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, performing PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtaining a second information bit stream;

[0039] Step 110, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies; if not, processing the second information bit stream to obtain an information bit stream of a frequency hopping signal.

[0040] The above-mentioned space-based Internet of Things communication frequency hopping processing method, device, equipment and storage medium obtain the frequency hopping signal of the ground terminal and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream; perform convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the ground terminal frequency hopping sequence number, calculate the ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtain a frequency hopping table; obtain the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculate the Doppler shift according to the theoretical frequency band of the current frequency band signal; obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler shift, perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtain a second information bit stream; determine whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points, if not, process the second information bit stream to obtain the information bit stream of the frequency hopping signal. The present invention does not need to store the terminal frequency hopping group in advance, but generates the terminal frequency hopping pattern online according to the ground terminal frequency hopping sequence number, thereby realizing a many-to-one communication mode. At the same time, the use of PSK coherent demodulation can greatly improve the utilization efficiency of the unit spectrum. When the frequency band resources are limited, the number of channel users accessing the channel per unit time can be increased as much as possible, thereby improving the channel access capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of a flow chart of a frequency hopping processing method for space-based Internet of Things communication in one embodiment;

[0042] Figure 2 A schematic diagram of a frequency hopping signal protocol frame format in one embodiment;

[0043] Figure 3 A schematic diagram of frequency hopping signal distribution in one embodiment;

[0044] Figure 4 It is a structural block diagram of a frequency hopping processing device for space-based Internet of Things communication in one embodiment;

[0045] Figure 5 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0046] 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.

[0047] It should be noted that in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0048] Frequency hopping communication has good anti-interference and anti-fading capabilities. It was mainly used in military communications in the early days. Later, frequency hopping communication technology was also adopted in civilian mobile communications. Typical mobile communication technologies include GSM and Bluetooth technology.

[0049] Frequency hopping communication technology is a special spread spectrum communication technology that uses pseudo-random codes to control the carrier frequency to randomly jump over a wider frequency band. Frequency hopping communication can be divided into fast frequency hopping and slow frequency hopping according to the relationship between the rate and the data transmission rate. The frequency hopping rate of fast frequency hopping is greater than the data transmission rate. Slow frequency hopping has relatively small requirements for modulation, and many modulation methods can be integrated into it, such as FSK, GMSK, PSK, etc.; in the fast frequency hopping mode, FSK is generally the most common.

[0050] Traditional frequency hopping communication generally uses non-coherent demodulation, which will cause system performance loss. Coherent demodulation has the problem of carrier phase ambiguity and is sensitive to phase noise, but the system performance is improved compared to non-coherent demodulation.

[0051] In satellite communication applications, the existing frequency hopping communication technology is often used in military communications, which adopts a complex spread frequency hopping mode, and the sender and receiver communicate one-to-one, and the frequency hopping sequence is known. Therefore, the present invention provides a frequency hopping processing method based on space-based Internet of Things communication, which has low processing complexity and can be well applied to space-based Internet of Things communication, and improves the channel receiving capacity on the existing spectrum resources.

[0052] In one embodiment, Figure 1 As shown, a frequency hopping processing method for space-based Internet of Things communication provided by the present invention includes:

[0053] Step 102: Acquire a frequency hopping signal from a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream.

[0054] Specifically, the ground terminal sends a frequency hopping signal during the satellite transit time period, and the onboard receiver is in working state. The time domain signal data stream collected by the AD converter is converted from the time domain to the frequency domain using the FFT signal processing method, and the spectrum peak is searched in the frequency domain. When the peak exceeds the set threshold, the spectrum position at this time is recorded, and it is considered that a valid frequency hopping signal is captured. The current signal frequency F(i) captured by FFT is sent to the frequency hopping signal processing module for processing to obtain the current signal frequency F(i); according to the current signal frequency F(i), the data stream collected by the AD converter is PSK coherently demodulated to obtain the first information bit stream.

[0055] It is worth noting that if Figure 2 As shown, the air interface protocol frame format in the space-based Internet of Things communication includes a synchronization header, a physical layer frame header, a physical layer frame header CRC, a physical layer payload, and a physical layer payload CRC; the air interface frame format is divided into two parts: the first part is the synchronization header + physical layer frame header + physical layer frame header CRC; the second part is the physical layer payload + physical layer payload CRC, wherein the physical layer frame header in the first part contains the ground terminal frequency hopping sequence number and the physical layer payload data frame length. The ground terminal frequency hopping signal composition is arranged in time as the synchronization header + physical layer frame header + physical layer frame header CRC occupying the first frequency point, and the remaining frequency hopping frequencies are evenly distributed in the second part of the data format according to a pseudo-random sequence. As shown Figure 3 As shown, the terminal frequency hopping signal is continuous in time and discretely distributed in frequency.

[0056] Step 104, performing convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the ground terminal frequency hopping sequence number, calculating the ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtaining a frequency hopping table.

[0057] Specifically, the frame synchronization word is searched according to the first information bit stream, and the frame synchronization word search method is: the information bit stream is continuously shifted in a serial manner and input into a 32-bit register cache, and the synchronization word composed of 32 bits is compared with the set 32-bit frame synchronization word to see if they are the same. If they are the same, the frame synchronization word is found; if the frame synchronization word is not found within a certain period of time, return to step 102, and if the frame synchronization word is found, the first information bit stream is convolutionally decoded according to the frame synchronization word, the physical frame header is obtained, the frequency hopping point number hop_num is calculated, and the ground terminal frequency hopping pattern is calculated according to the ground terminal frequency hopping sequence number in the physical frame header to obtain the frequency hopping table. It is worth noting that the physical layer payload data frame length can be obtained from the first information bit stream, and the frequency hopping point number hop_num can be obtained from the physical layer payload data frame length. For example, assuming that the physical layer payload data frame length is N, the number of frequency hopping points is (N / (1 / 2))*8 / 48, where 1 / 2 represents the convolutional coding rate, (N / (1 / 2)) represents the data length after convolutional coding (Byte), (N / (1 / 2))*8 represents the data length after convolutional coding (bit), and 48 represents that the data length of each frequency hopping frequency band is 48 bits. Therefore, the number of frequency hopping points is (N / (1 / 2))*8 / 48.

[0058] The frequency hopping pattern of the present invention is realized by a 6-order linear feedback shift register, i.e., 6order LFSR. Specifically, the physical frame header contains a 10-bit ground terminal frequency hopping sequence number. The first 4 bits of the frequency hopping sequence number are used to select which of the generating polynomials of the 6-order LFSR is, for example, there are these generating polynomials {33, 45, 48, 51, 54, 57}, and the last 6 bits are used to perform XOR with the register of the 6-order LFSR to generate a frequency hopping pattern. At the same time, the ground terminal frequency hopping sequence number is unique, i.e., it is determined by 10 bits, and there are N types for N terminals. Therefore, the satellite receiver does not need to know the ground terminal frequency hopping sequence number in advance, but obtains the frequency hopping sequence number of the terminal according to the physical frame header after convolution decoding, and then generates the frequency hopping pattern online. The frequency hopping table of the present invention contains the frequency points required by the satellite receiver when de-hopping, and each frequency hopping band corresponds to a frequency point, which is used for the digital IQ orthogonal mixing module in PSK coherent demodulation.

[0059] Step 106, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal.

[0060] Specifically, according to the frequency hopping table, the theoretical frequency band f(i) of the current frequency band signal is obtained, and the frequency at the last moment tracked by PSK coherent demodulation at the last moment of the current signal frequency band is set as Ff(i). According to the theoretical frequency band f(i) of the current frequency band signal and the frequency Ff(i) of the current frequency band signal at the last moment, the Doppler shift Fd(i)=Ff(i)-f(i) is obtained. It can be understood that Ff(i)=K*t+F(i), where t represents time. If the transmission time of the current frequency band signal is T, the value range of t is 0<=t<=T, and K is a proportional factor, that is, the frequency at the last moment tracked by PSK coherent demodulation at the last moment is Ff(i)=K*T+F(i).

[0061] Step 108, obtaining the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtaining the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, performing PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtaining a second information bit stream.

[0062] Specifically, according to the frequency hopping table, the theoretical frequency of the next frequency band signal is f(i+1), so the tracking frequency of the next frequency band F(i+1)=Fd(i)+f(i+1). With the signal frequency F(i+1) as the starting frequency, PSK coherent demodulation is performed to obtain the second information bit stream, and the second information bit stream is saved. It is worth noting that there are as many second information bit streams as there are frequency hopping points.

[0063] Step 110, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies, if not, processing the second information bit stream to obtain an information bit stream of the frequency hopping signal.

[0064] It is worth noting that the frequency hopping signal includes physical payload frame data and CRC, and after processing the second information bit stream, an information bit stream of the physical payload frame data is obtained.

[0065] Specifically, it is determined whether the number of the current tracking signal frequency band i is less than the number of frequency hopping points hop_num. If so, it returns to step 106, re-determines the frequency point of the current theoretical frequency band, and performs PSK coherent demodulation for tracking the next frequency band. Otherwise, the second information bit stream is sequentially deinterleaved, convolutionally decoded, and descrambled to obtain the information bit stream of the physical payload frame data. The state of the satellite receiver returns to step 102, completing the reception process of the current frequency hopping signal, and preparing for the next frequency hopping signal reception process.

[0066] The above-mentioned frequency hopping processing method for space-based Internet of Things communication is the frequency hopping processing flow of the satellite receiver. This processing method is a frequency hopping processing method based on the coherent demodulation mode. The method used for frequency hopping synchronization is the synchronization header method. This method has a fast synchronization speed and is suitable for space-based Internet of Things communication scenarios. At the same time, since the satellite receiver does not need to store the terminal frequency hopping pattern in advance, it can generate the frequency hopping pattern online according to the terminal information in the physical frame header, so many-to-one communication can be achieved. The basic modulation method used is PSK, which can greatly improve the utilization efficiency of the unit spectrum. When the frequency band resources are limited, the number of channel users accessing the unit time can be increased as much as possible, thereby improving the channel access capacity.

[0067] 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.

[0068] In one embodiment, Figure 4 As shown, a space-based Internet of Things communication frequency hopping processing device is provided, including: a signal acquisition module, a convolution decoding module, a Doppler frequency shift calculation module, a tracking frequency calculation module and an information bit stream processing module, wherein:

[0069] The signal acquisition module is used to acquire the frequency hopping signal of the ground terminal and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream.

[0070] The convolution decoding module is used to perform convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the ground terminal frequency hopping sequence number, calculate the ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtain the frequency hopping table.

[0071] The Doppler frequency shift calculation module obtains the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculates the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal.

[0072] The tracking frequency calculation module is used to obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, and perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency to obtain the second information bit stream.

[0073] The information bit stream processing module determines whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points. If not, the second information bit stream is processed to obtain the information bit stream of the frequency hopping signal.

[0074] For the specific definition of the space-based Internet of Things communication frequency hopping processing device, please refer to the definition of the space-based Internet of Things communication frequency hopping processing method mentioned above, which will not be repeated here. Each module in the above-mentioned space-based Internet of Things communication frequency hopping processing device can be implemented in whole or in part by 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.

[0075] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 5 As shown. The computer device includes a processor, a memory, a network interface and a database connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store space-based Internet of Things communication frequency hopping data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a space-based Internet of Things communication frequency hopping processing method is implemented.

[0076] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0077] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0078] Step 102: Acquire a frequency hopping signal from a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream.

[0079] Step 104, performing convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the ground terminal frequency hopping sequence number, calculating the ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtaining a frequency hopping table.

[0080] Step 106, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal.

[0081] Step 108, obtaining the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtaining the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, performing PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtaining a second information bit stream.

[0082] Step 110, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies, if not, processing the second information bit stream to obtain an information bit stream of the frequency hopping signal.

[0083] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0084] Step 102: Acquire a frequency hopping signal from a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream.

[0085] Step 104, performing convolution decoding on the first information bit stream to obtain the number of frequency hopping points and the ground terminal frequency hopping sequence number, calculating the ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtaining a frequency hopping table.

[0086] Step 106, obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal.

[0087] Step 108, obtaining the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtaining the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, performing PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtaining a second information bit stream.

[0088] Step 110, determining whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping frequencies, if not, processing the second information bit stream to obtain an information bit stream of the frequency hopping signal.

[0089] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0090] 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.

[0091] 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 frequency hopping processing method for space-based Internet of Things communication, characterized in that: The method comprises: Acquire a frequency hopping signal of a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream; Performing convolution decoding on the first information bit stream to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, calculating a ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtaining a frequency hopping table; Acquire the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculate the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal; Obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency, and obtain a second information bit stream; Determine whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points. If so, return to the frequency hopping table to re-determine the theoretical frequency band of the current frequency band signal and perform PSK coherent demodulation to track the next frequency band; if not, process the second information bit stream to obtain the information bit stream of the frequency hopping signal.

2. The space-based Internet of Things communication frequency hopping processing method according to claim 1, characterized in that: The air interface protocol frame format in space-based IoT communication includes synchronization header, physical layer frame header, physical layer frame header CRC, physical layer payload and physical layer payload CRC; The physical layer frame header includes a ground ground terminal frequency hopping sequence number.

3. The space-based Internet of Things communication frequency hopping processing method according to claim 1 or 2, characterized in that: Acquiring a frequency hopping signal of a ground terminal and performing PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream, including: The satellite receiver captures the frequency hopping signal and sends the frequency hopping signal to the frequency hopping signal processing module for processing to obtain the current signal frequency; According to the current signal frequency, PSK coherent demodulation is performed on the data stream collected by the AD converter to obtain a first information bit stream.

4. The space-based Internet of Things communication frequency hopping processing method according to claim 3 is characterized in that: When the satellite-borne receiver captures the frequency hopping signal, the FFT signal processing method is adopted.

5. The space-based Internet of Things communication frequency hopping processing method according to claim 3, characterized in that: The first information bit stream is convolutionally decoded to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, and a ground terminal frequency hopping pattern is calculated according to the ground terminal frequency hopping sequence number to obtain a frequency hopping table, including: A frame synchronization word is found according to the first information bit stream, and the first information bit stream is convolutionally decoded according to the frame synchronization word to obtain a physical frame header, and the number of frequency hopping points is obtained by calculation, and the ground terminal frequency hopping pattern is calculated according to the ground terminal frequency hopping sequence number in the physical frame header to obtain a frequency hopping table.

6. The space-based Internet of Things communication frequency hopping processing method according to claim 5, characterized in that: Obtaining the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculating the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal, including: According to the frequency hopping table, the theoretical frequency band f(i) of the current frequency band signal is obtained, and the last moment frequency tracked by PSK coherent demodulation at the last moment of the current signal frequency band is set as Ff(i). According to the theoretical frequency band f(i) of the current frequency band signal and the last moment frequency Ff(i), the Doppler shift Fd(i) = Ff(i)- f(i) is obtained.

7. The space-based Internet of Things communication frequency hopping processing method according to claim 6, characterized in that: Determine whether the number of the current tracking signal frequency band is less than the number of frequency hopping points. If so, return to the frequency hopping table to re-determine the theoretical frequency band of the current frequency band signal and perform PSK coherent demodulation for tracking the next frequency band; If not, the second information bit stream is processed to obtain an information bit stream of a frequency hopping signal, including: Determine whether the number of the current tracking signal frequency band is less than the number of frequency hopping points. If so, return to the frequency hopping table to re-determine the theoretical frequency band of the current frequency band signal and perform PSK coherent demodulation for tracking the next frequency band; If not, the second information bit stream is sequentially deinterleaved, convolutionally decoded and descrambled to obtain an information bit stream of the physical payload frame data.

8. A frequency hopping processing device for space-based Internet of Things communication, characterized in that: The device comprises: A signal acquisition module, used to acquire a frequency hopping signal of a ground terminal, and perform PSK coherent demodulation on the frequency hopping signal to obtain a first information bit stream; A convolution decoding module, configured to perform convolution decoding on the first information bit stream to obtain a frequency hopping point number and a ground terminal frequency hopping sequence number, calculate a ground terminal frequency hopping pattern according to the ground terminal frequency hopping sequence number, and obtain a frequency hopping table; A Doppler frequency shift calculation module, which obtains the theoretical frequency band of the current frequency band signal through the frequency hopping table, and calculates the Doppler frequency shift according to the theoretical frequency band of the current frequency band signal; A tracking frequency calculation module is used to obtain the theoretical frequency of the next frequency band signal according to the frequency hopping table, and obtain the next frequency band tracking frequency according to the theoretical frequency of the next frequency band signal and the Doppler frequency shift, and perform PSK coherent demodulation with the next frequency band tracking frequency as the starting frequency to obtain a second information bit stream; The information bit stream processing module determines whether the number of frequency bands of the current tracking signal is less than the number of frequency hopping points. If so, it returns to the frequency hopping table to redetermine the theoretical frequency band of the current frequency band signal and performs PSK coherent demodulation to track the next frequency band; if not, it processes the second information bit stream to obtain the information bit stream of the frequency hopping signal.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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