Radio astronomy signal and radio frequency interference simulation method and its application, equipment and medium

Abstract

The present invention relates to a radio astronomy signal and radio frequency interference simulation method and its application, equipment and medium, including alternative radio astronomy signal generation, alternative radio frequency interference generation, current radio astronomy signal and radio frequency interference generation, antenna array simulation, acquisition system simulation, network transmission simulation and source data generation, etc., which can randomly generate mixed signals containing radio astronomy signals and radio frequency interference in time domain, frequency domain, space domain and power domain based on measured and simulated signals, and generate data sets by simulating different receiving antenna arrays and acquisition system responses, which can be transmitted to the radio astronomy signal processing system through the network as test data, and can also generate source data with labels required for deep learning to provide support for scientific research. Compared with the prior art, the present invention solves the problem of generating test data required for the back-end processing system of the radio telescope by combining simulation with measured signal utilization, and the simulated signals and scenes are more complex and realistic.

Description

Technical Field

[0001] The present invention relates to the field of radio astronomy signal processing, and in particular to a radio astronomy signal and radio frequency interference simulation method and application, equipment and medium thereof. Background Art

[0002] In recent years, many large-scale radio telescope systems have been established internationally, including China's FAST and Australia's ASKAP. These radio telescopes consist of a receiving array composed of multiple antennas, a multi-channel receiving and acquisition system, and a back-end signal processing system. The debugging and testing of the back-end signal processing system of a radio telescope requires a large amount of test data. The current main approach is to rely on measured data as a test source. This approach has three problems: (1) In reality, most astronomical signals, such as fast radio bursts, are low-probability events. This limitation in number makes the testing of the newly built back-end processing system insufficient, which prolongs the debugging time of the system; (2) Radio frequency interference is one of the challenges faced by radio telescopes. Its main source is human production and life. With the development of technology, the performance of radio astronomy equipment in terms of sensitivity, receiving bandwidth, and observation field of view has been significantly improved. However, at the same time, the number of sources of radio frequency interference has increased, seriously affecting astronomical observations. In order to cope with the increasingly complex electromagnetic environment, the research and successful application of RF interference reduction methods have become the key to ensuring the operating efficiency and observation quality of radio telescopes. The limited measured data often have a single scene and a limited amount of interference, which makes it difficult to support comprehensive testing of the system; (3) With the development of artificial intelligence technology, data-driven RF interference reduction algorithms and radio astronomy signal search and identification algorithms will become a major research direction in the future, but the current data cannot support it in terms of both quantity and quality.

[0003] Therefore, it is necessary to develop a signal simulation method to generate signals of sufficient quantity and quality to meet the actual needs of future radio telescope signal processing system testing and the massive data requirements of scientific research on radio astronomy signal processing based on artificial intelligence. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a radio astronomy signal and radio frequency interference simulation method and its application, equipment and medium, provide a test source for the large-scale back-end data processing system of the radio astronomy telescope, and provide massive high-quality data support containing labels for the scientific research of radio astronomy signals.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] According to a first aspect of the present invention, there is provided a method for simulating radio astronomy signals and radio frequency interference, comprising the following steps:

[0007] Alternative radio astronomy signal generation: used to generate and store alternative radio astronomy signals based on simulated or measured signals;

[0008] Alternative RF interference generation: used to generate and store alternative RF interference based on simulated or measured signals;

[0009] The generation of radio astronomy signals and radio frequency interference at that time: based on the set probability of occurrence of radio astronomy signals, determine whether the current simulation needs to add astronomical radio signals. If necessary, randomly select a signal from the stored candidate radio astronomy signals, and randomly generate a time starting point to obtain the radio astronomy signal added at that time; based on the set maximum number of radio frequency interferences, randomly generate the number of interferences at that time, randomly select a signal from the stored candidate radio frequency interferences, determine whether the selected signal meets the bandwidth conditions, and if so, use it as the radio frequency interference baseband signal, and obtain the radio frequency interference after frequency modulation and power adjustment;

[0010] Antenna array simulation: Generate array manifolds according to the configuration, randomly generate radio astronomy signals and radio frequency interference incident angles within the set range, simulate the effect of signals at different angles passing through the array, generate mixed signals corresponding to different receiving channels based on the results of the radio astronomy signals and radio frequency interference, and add noise;

[0011] Acquisition system simulation: perform orthogonal down-conversion, low-pass filtering, channelization and down-sampling processing on the signal of each receiving channel, and perform fixed-point processing on the output data as needed, and store the second signal information and signal data in a fixed format, including broadband data before channelization and sub-band data after channelization. The second signal information includes the number of signals, signal type, time start and end point, frequency start and end point, and the signal type is radio astronomy signal or radio frequency interference.

[0012] As a preferred technical solution, the alternative radio astronomy signal generation includes two parts: radio astronomy signal simulation and measured astronomy signal loading and utilization. The radio astronomy signal simulation part generates a simulated radio astronomy signal and performs a first signal processing, and then stores the first signal information and signal data of the signal in a fixed format. The measured astronomy signal loading and utilization part performs a second signal processing on the measured astronomy signal, and then stores the first signal information and signal data of the signal in a fixed format.

[0013] The alternative RF interference generation includes two parts: simulation of various types of modulated RF interference signals and loading and utilizing of measured RF interference signals. The simulation part of various types of modulated RF interference signals generates simulated RF interference and performs a first signal processing before storing the first signal information and signal data of the signal in a fixed format. The loading and utilizing part of the measured RF interference signal performs a third signal processing on the measured RF interference signal before storing the first signal information and signal data of the signal in a fixed format.

[0014] The first signal information includes sampling rate, duration, frequency start point and end point.

[0015] As a preferred technical solution, the first signal processing is specifically power normalization processing;

[0016] The second signal processing is specifically: performing frequency domain filtering, time domain truncation, resampling and power normalization processing according to the time starting point, duration, center frequency, bandwidth and sampling rate of the measured signal;

[0017] The third signal processing is specifically: frequency domain filtering, time domain truncation, resampling and frequency normalization are performed according to the time starting point, duration, center frequency, bandwidth and sampling rate of the measured signal, and down-converted to 0 Hz.

[0018] As a preferred technical solution, the radio astronomy signal simulation part simulates and generates a fast radio burst pulse signal, and the sampling rate Fs is set according to actual needs. The center frequency of the signal f 0 MHz, bandwidth BW MHz, duration T The second is generated in a random pattern or set in a fixed pattern, the dispersion of the signal DM Randomly generated or fixed configuration, where the dispersion corresponds to the interstellar medium transmission function H for:

[0019] ,

[0020] in, D is the dispersion constant (4148.808MHz 2 pc -1 cm 3 s), f is the frequency, f 0 - BW / 2< f < f 0 + BW / 2;

[0021] Pulse signal g ( t) in the form of a Gaussian pulse:

[0022] ,

[0023] in, A is the amplitude, t For the current moment, t c is the pulse center moment, and σ is the standard deviation, which is half of the Gaussian pulse width.

[0024] As a preferred technical solution, the radio astronomy signal and radio frequency interference generation at that time includes the following sub-steps:

[0025] S31, setting a single simulation duration of L seconds, where L should be greater than the duration T of the generated radio astronomy signal;

[0026] S32, random addition of radio astronomy signals: generating a simulation addition flag for the current time according to a preset probability of occurrence of radio astronomy signals;

[0027] If the add flag is 1, a signal data is randomly read from the stored alternative radio astronomy signal data file. a ( t ), randomly generate the starting time of radio astronomy signal sT 0 , then the signal end point is sT 1 , sT 1 = sT 0 + T , T is the signal duration, thereby generating a new radio astronomy signal s ( t ):

[0028] ;

[0029] If the add flag is 0, no radio astronomy signal will be added this time;

[0030] S33, according to the set maximum number of radio frequency interference, generate the number of interferences for this mixing N , in the entire effective time-frequency space corresponding to the sampling rate Fs, randomly generate the i ( i =1,2,… N ) time-frequency range of radio frequency interference[ JT 0 ( i ), JT 1 ( i )]and[ JF0 ( i ), JF 1 ( i )], JT 0 ( i )and JT 1 ( i ) represent the i The start and end time of the radio frequency interference, JF 0 ( i )and JF 1 ( i ) represent the i The starting and ending positions of the frequency band where the radio frequency interference is located;

[0031] S34, randomly selecting a signal from the stored candidate radio frequency interference data file, reading the first signal information therein and calculating the signal bandwidth JBW ( i ), if satisfied JBW ( i )< JF 1 ( i )- JF 0 ( i ), then the signal is used as the i Baseband signal of RF interference J ( i , t )( i =1, 2, … N ), if all signal bandwidths do not meet the conditions, then regenerate [ JF 0 ( i ), JF 1 ( i )] and then re-execute this step until a RF interference baseband signal that meets the conditions is found;

[0032] S35, RF interference frequency modulation: baseband signal J ( i , t )( i =1,2,… N ) to perform frequency conversion and obtain the initial RF interference Jam 0 ( i , t )= j ( i , t )*exp[j 2π f c ( i ) t ],in f c ( i )= JF 0 ( i )+0.5 JBW ( i );

[0033] S36, RF interference power adjustment: Randomly generate interference power coefficient according to the set interference power range G i , and get the final RF interference: Jam ( i , t )= G i Jam 0 ( i , t ).

[0034] As a preferred technical solution, the antenna array simulation includes the following sub-steps:

[0035] S41, array and incident angle generation: configure array manifolds, including uniform linear arrays, circular arrays, and square arrays, and configure the number of array elements with the geometric center of the antenna array as the center. M and spacing, configuring the incident angle of the radio astronomy signal by randomly generating or fixing it ( α s , β s ) and the incident angle of the RF interference [ α J ( i ), β J ( i )]( i =1,2,… N );

[0036] S42, array signal generation:

[0037] S421, perform Fourier transform on the radio astronomy signal and radio frequency interference to obtain the radio astronomy signal spectrum S ( f )=FFT( s ( t )) and RF interference spectrum Jam ( i , f )=FFT( Jam (i , t )) ( i =1,2,… N );

[0038] For k The frequency domain response of the array element is:

[0039] ,

[0040] Among them τ k ( α , β ) indicates the opponent k ( x k , y k , z k ), the azimuth is α , the pitch angle is β The corresponding delay is:

[0041] ,

[0042] ,

[0043] From this we get m ( m =1,2,… M ) receiving channels corresponding to the time domain signal is: x m ( t ) = FFT -1 ( X m ( f )) ,in, M is the total number of receiving channels;

[0044] S43, signal noise: randomly generate noise level according to the set range, generate and add Gaussian white noise according to the noise level n m ( t ), the mixed signal is: x m '( t )= x m ( t )+ n m ( t ).

[0045] According to a second aspect of the present invention, an application of a radio astronomy signal and radio frequency interference simulation method is provided, wherein the simulation method as described above is used for simulation to generate a test data set for system testing, and the test data set is packaged in a user-specified format according to requirements and transmitted to a back-end processing system via a network for testing.

[0046] According to a third aspect of the present invention, an application of a radio astronomy signal and radio frequency interference simulation method is provided. The simulation method as described above is used for simulation. Short-time Fourier transform is performed on the data before or after channelization as needed to obtain two-dimensional time-frequency distribution data, and the time-frequency data is saved. At the same time, corresponding label data marked by pixel points is generated according to the second signal information and saved for subsequent scientific research. In the label data, the pixel points corresponding to the radio frequency interference are marked as 1, the pixel points corresponding to the radio astronomy signal are marked as 2, and the others are marked as 0.

[0047] According to a fourth aspect of the present invention, there is provided an electronic device, comprising a memory and a processor, wherein a computer program is stored in the memory, and the method described is implemented when the processor executes the program.

[0048] According to a fifth aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the program implements the method described when executed by a processor.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] (1) The present invention provides a method for simulating radio astronomy signals and radio frequency interference, which can simulate radio astronomy signals with dispersion processes and radio frequency interference of various types of modulation, and realize signal mixing in four dimensions: time domain, frequency domain, spatial domain and power domain, so as to more realistically simulate the targets and complex and changeable electromagnetic environment faced by radio telescopes.

[0051] (2) The present invention adopts a combination of virtual and real methods. In addition to simulating the generated signals, the astronomical radio signals and radio frequency interference collected in practice can be introduced into the system simulation process after preprocessing, which greatly improves the application scope and effect of the measured data.

[0052] (3) The present invention can generate high-quality radio astronomy signals in batches, solving the problem of simulating massive radio astronomy signals. It is suitable for testing the back-end signal processing subsystem of large-scale radio astronomy signal systems and for scientific research in the field of radio astronomy, meeting the needs of practical engineering applications and scientific research. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 is a flow chart of the method of the present invention;

[0054] Figure 2A time-frequency diagram of a radio astronomy signal generated by simulation in one embodiment;

[0055] Figure 3 A randomly generated time-frequency distribution of radio frequency interference in one embodiment;

[0056] Figure 4 is a pixel-by-pixel label of a time-frequency distribution in one embodiment;

[0057] Figure 5 A structural diagram of an electronic device in an embodiment. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0059] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0060] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent.

[0061] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0062] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation, and may represent the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0063] Example 1

[0064] This embodiment provides a method for simulating radio astronomy signals and radio frequency interference, such as Figure 1 As shown, the following steps are included:

[0065] S1, alternative radio astronomy signal generation: used to generate and store alternative radio astronomy signals based on simulated or measured signals.

[0066] This step includes two parts: radio astronomy signal simulation and measured astronomy signal loading and utilization. The radio astronomy signal simulation part generates a simulated radio astronomy signal and performs a first signal processing, then stores the first signal information and signal data of the signal in a fixed format. The measured astronomy signal loading and utilization part performs a second signal processing on the measured astronomical signal, then stores the first signal information and signal data of the signal in a fixed format.

[0067] S11, radio astronomy signal simulation

[0068] According to the needs, the fast radio burst pulse signal can be simulated and generated. The sampling rate Fs is set according to the actual needs, and the center frequency of the signal f 0 MHz, bandwidth BW MHz, duration TThe second is generated in a random pattern or set in a fixed pattern, the dispersion of the signal DM It can be randomly generated or fixed in configuration, where the dispersion corresponds to the interstellar medium transmission function H for:

[0069] ,

[0070] in, D is the dispersion constant (4148.808MHz 2 pc -1 cm 3 s), f is the frequency, f 0 - BW / 2< f < f 0 + BW / 2.

[0071] Pulse signal g ( t ) in the form of a Gaussian pulse:

[0072] ,

[0073] in, A is the amplitude, t For the current moment, t c is the pulse center moment, and σ is the standard deviation, which is half of the Gaussian pulse width.

[0074] After the generated pulse signal is power normalized, the signal information (sampling rate, duration, frequency start and end point) and signal data are stored locally as an alternative signal according to preset rules.

[0075] S12, loading and utilization of measured astronomical signals

[0076] As needed, the measured astronomical signal baseband data can be introduced into the simulation process. According to the measured baseband astronomical signal time starting point, duration, center frequency, bandwidth and sampling rate, frequency domain filtering, time domain interception, resampling, power normalization and other preprocessing are performed, and the signal information (sampling rate, duration, frequency starting point and end point) and signal data are stored locally as alternative signals according to preset rules.

[0077] S2, alternative RF interference generation: used to generate and store alternative RF interference based on simulated or measured signals.

[0078] This step includes two parts: simulation of various types of modulated RF interference signals and loading and utilizing actually measured RF interference signals. The simulation part of various types of modulated RF interference signals generates simulated RF interference signals and performs a first signal processing, and then stores the first signal information and signal data of the signal in a fixed format. The loading and utilizing part of actually measured RF interference signals performs a third signal processing on the actually measured RF interference signals and then stores the first signal information and signal data of the signal in a fixed format.

[0079] S21, simulation of various modulated RF interference signals

[0080] As needed, it supports the generation of various common modulated electromagnetic signals, including AM, FM, CW, LFM, MFSK, MPSK, MQAM, MAPSK, and MSK. The modulation style, bandwidth, and duration of the RF interference can be generated in a random mode or set in a fixed mode. The center frequency is fixed to 0. After the generated RF interference is power normalized, the signal information (sampling rate, duration, frequency start and end point) and signal data are stored locally according to preset rules as alternative RF interference.

[0081] S22, measured RF interference signal loading and utilization

[0082] As needed, the measured RF interference can be introduced into the simulation process as a data source. According to the measured RF interference time starting point, duration, center frequency, bandwidth and original sampling rate, the data is filtered in the frequency domain, intercepted in the time domain, resampled, and power normalized, and then down-converted to 0Hz. The signal information (sampling rate, duration, frequency starting point and end point) and signal data are stored locally according to preset rules as alternative RF interference.

[0083] S3, when radio astronomy signal and radio frequency interference are generated: based on the set probability of occurrence of radio astronomy signal, determine whether astronomical radio signal needs to be added to the current simulation. If necessary, randomly select a signal from the stored candidate radio astronomy signals, and randomly generate the time starting point to obtain the radio astronomy signal added this time; based on the set maximum number of radio frequency interference, randomly generate the number of interferences at this time, randomly select a signal from the stored candidate radio frequency interferences, and determine whether the selected signal meets the bandwidth condition. If it meets the condition, use it as the radio frequency interference baseband signal, and after frequency modulation and power adjustment, that is, randomize the time domain (time starting point and end point), frequency domain (frequency domain starting point and bandwidth) and power to obtain radio frequency interference.

[0084] When radio astronomy signals and radio frequency interference occur, the following sub-steps are included:

[0085] S31, setting a single simulation duration of L seconds, where L should be greater than the duration T of the generated radio astronomy signal.

[0086] S32, radio astronomy signals are randomly added:

[0087] According to the preset probability of occurrence of radio astronomy signals, the simulation addition mark is automatically generated;

[0088] If the add flag is 1, a signal data is randomly read from the stored alternative radio astronomy signal data file. a ( t ), randomly generate the starting time of radio astronomy signal sT 0 , then the signal end point is sT 1 , sT 1 = sT 0 + T , T is the signal duration, thereby generating a new radio astronomy signal s ( t ), expressed as:

[0089] ;

[0090] If the add flag is 0, no radio astronomy signal is added this time.

[0091] The fast radio burst signal simulated and generated in this embodiment is as follows Figure 2 shown.

[0092] S33, according to the set maximum number of radio frequency interference, generate the number of interferences for this mixing N , in the entire effective time-frequency space corresponding to the sampling rate Fs, randomly generate the i ( i =1,2,… N ) time-frequency range of radio frequency interference[ JT 0 ( i ), JT 1 ( i )]and[ JF 0 ( i ), JF 1 ( i )], JT 0 ( i )and JT 1 ( i ) represent the i The start and end time of the radio frequency interference, JF 0 ( i )and JF 1 ( i ) represent the i The starting and ending positions of the frequency band where the RF interference is located.

[0093] S34, randomly selecting a signal from the stored candidate radio frequency interference data file, reading the first signal information therein and calculating the signal bandwidth JBW ( i ), if satisfied JBW ( i )< JF 1 ( i )- JF 0 ( i ), then the signal is used as the i Baseband signal of RF interference J ( i , t )( i =1, 2, … N ), if all signal bandwidths do not meet the conditions, then regenerate [ JF 0 ( i ), JF 1 ( i )] and then re-execute this step until a RF interference baseband signal that meets the conditions is found.

[0094] S35, RF interference frequency modulation: baseband signal J ( i , t )( i =1,2,… N ) to perform frequency conversion and obtain the initial RF interference Jam 0 ( i , t )= j ( i , t )*exp[ j 2π f c ( i ) t ],in f c ( i )= JF 0 ( i )+0.5 JBW ( i ).

[0095] S36, RF interference power adjustment: Randomly generate interference power coefficient according to the set interference power range G i , and get the final RF interference: Jam ( i , t )= G i Jam 0 ( i , t ).

[0096] In this step, it can be found that the number of RF interference is random, the time start and end point are random, the frequency start and bandwidth are random, and the power is random. The typical RF interference time-frequency distribution is as follows: Figure 3 shown.

[0097] S4, antenna array simulation: Generate array manifolds according to the configuration, randomly generate incident angles of radio astronomy signals and radio frequency interference within the set range, simulate the effects of signals at different angles passing through the array, generate mixed signals corresponding to different receiving channels based on the results of the radio astronomy signals and radio frequency interference, and add noise.

[0098] Antenna array simulation, including the following sub-steps:

[0099] S41, array and incident angle generation: configure array manifolds, including uniform linear arrays, circular arrays, and square arrays, and configure the number of array elements with the geometric center of the antenna array as the center. M and spacing, configuring the incident angle of the radio astronomy signal by randomly generating or fixing it ( α s , β s )and N The incident angle of the RF interference [ α J ( i ), β J ( i )]( i =1,2,… N ).

[0100] S42, array signal generation:

[0101] S421, perform Fourier transform on the radio astronomy signal and radio frequency interference to obtain the radio astronomy signal spectrum S ( f )=FFT( s ( t )) and RF interference spectrum Jam ( i , f )=FFT( Jam ( i , t )) ( i =1,2,… N );

[0102] For k The frequency domain function of array elements is:

[0103] ,

[0104] Among them τ k ( α , β ) indicates the opponent k ( x k , y k , z k ), the azimuth is α , the pitch angle is β The corresponding delay is:

[0105] ,

[0106] ,

[0107] From this we get m ( m =1,2,… M ) receiving channels corresponding to the time domain signal is: x m ( t ) = FFT -1 ( X m ( f )) ,in, M is the total number of receiving channels;

[0108] S43, signal noise: randomly generate noise level according to the set range, generate and add Gaussian white noise according to the noise level n m ( t ), the mixed signal is: x m '( t )= x m ( t )+ n m ( t ).

[0109] S5, acquisition system simulation: perform orthogonal down-conversion, low-pass filtering, channelization and down-sampling processing on the signal of each receiving channel, and support fixed-point processing of the output data as required (the fixed-point bit width is configurable), and store the second signal information (number of signals, time start and end, frequency start and end) and signal data of the broadband signal before channelization and the sub-band signal after channelization in a fixed format.

[0110] For example, after the received 600MHz~1800MHz signal is directly sampled at 3.93216GHz, it can be first orthogonally down-converted to 0 frequency to form a -600MHz~600MHz complex signal, and then low-pass filtered and 2048-point channelization operation is performed to obtain the signals corresponding to 2048 narrowband sub-channels, which are stored as 16-bit precision fixed-point numbers.

[0111] Example 2

[0112] This embodiment provides an application of a radio astronomy signal and radio frequency interference simulation method, which uses the simulation method described in the above embodiment 1 to simulate, generate a test data set for system testing, and package the test data set according to the user-specified format (such as the VLBI Data Interface Specification (VDIF)) according to the requirements and transmit it to the back-end processing system through the network for testing. In one embodiment, it can be transmitted to a specified network address via UDP.

[0113] Example 3

[0114] This embodiment provides an application of a method for simulating radio astronomical signals and radio frequency interference. The simulation method described in the above embodiment 1 is used for simulation. For scientific research, the original data is subjected to a short-time Fourier transform to obtain two-dimensional time-frequency distribution data. While saving the time-frequency data, corresponding label data marked by pixels is generated and saved (in mat form) for use by a deep learning network. In one implementation, in the label data, the pixel corresponding to the radio frequency interference is marked as 1, the pixel corresponding to the radio astronomical signal is marked as 2, and the others are marked as 0. Figure 4 For the corresponding Figure 3 The time-frequency distribution of the signal is shown with pixel-by-pixel labels.

[0115] Example 4

[0116] In one embodiment, an electronic device provided by an embodiment of the present invention includes one or more processors for implementing an asynchronous switching and optimal control method for a heterogeneous multi-agent system in the above embodiment.

[0117] like Figure 5As shown, the electronic device includes one or more processors (CPU), an input / output interface, a network interface and a memory.

[0118] Multiple components in the device are connected to the I / O interface, including: input units, such as keyboards, mice, etc.; output units, such as various types of displays, speakers, etc.; storage units, such as disks, optical disks, etc.; and communication units, such as network cards, modems, wireless communication transceivers, etc. The communication unit allows the device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunication networks.

[0119] The processor performs the various methods and processes described above, such as methods S1 to S5. For example, in some embodiments, methods S1 to S5 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program may be loaded and / or installed on the device via a ROM and / or a communication unit. When the computer program is loaded into the RAM and executed by the CPU, one or more steps of methods S1 to S5 described above may be performed. Alternatively, in other embodiments, the CPU may be configured to execute methods S1 to S5 in any other appropriate manner (e.g., by means of firmware).

[0120] The functions described above herein may be performed at least in part by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that may be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), complex programmable logic devices (CPLDs), and the like.

[0121] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code can be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0122] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0123] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0124] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for simulating radio astronomy signals and radio frequency interference, characterized in that: The following steps are involved: Alternative radio astronomy signal generation: used to generate alternative radio astronomy signals based on simulation and measured signals and store them; the alternative radio astronomy signal generation includes two parts: radio astronomy signal simulation and measured astronomy signal loading and utilization, wherein the radio astronomy signal simulation part generates a simulated radio astronomy signal and performs a first signal processing and then stores the first signal information and signal data of the signal in a fixed format, and the measured astronomy signal loading and utilization part performs a second signal processing on the measured astronomy signal and then stores the first signal information and signal data of the signal in a fixed format; the first signal information includes sampling rate, duration, frequency start point and end point; Alternative RF interference generation: used to generate and store alternative RF interference based on simulation and measured signals; the alternative RF interference generation includes two parts: simulation of various types of modulated RF interference signals and loading and utilizing measured RF interference signals, wherein the simulation part of various types of modulated RF interference signals generates simulated RF interference and performs a first signal processing before storing the first signal information and signal data of the signal in a fixed format, and the loading and utilizing part of the measured RF interference signal performs a third signal processing on the measured RF interference signal before storing the first signal information and signal data of the signal in a fixed format; The generation of radio astronomy signals and radio frequency interference at that time: based on the set probability of occurrence of radio astronomy signals, determine whether the current simulation needs to add astronomical radio signals. If necessary, randomly select a signal from the stored candidate radio astronomy signals, and randomly generate a time starting point to obtain the radio astronomy signal added at that time; based on the set maximum number of radio frequency interferences, randomly generate the number of interferences at that time, randomly select a signal from the stored candidate radio frequency interferences, determine whether the selected signal meets the bandwidth conditions, and if so, use it as the radio frequency interference baseband signal, and obtain the radio frequency interference after frequency modulation and power adjustment; Antenna array simulation: Generate array manifolds according to the configuration, randomly generate radio astronomy signals and radio frequency interference incident angles within the set range, simulate the effect of signals at different angles passing through the array, generate mixed signals corresponding to different receiving channels based on the results of the radio astronomy signals and radio frequency interference, and add noise; Acquisition system simulation: perform orthogonal down-conversion, low-pass filtering, channelization and down-sampling processing on the signal of each receiving channel, and perform fixed-point processing on the output data as needed, and store the second signal information and signal data in a fixed format, including broadband data before channelization and sub-band data after channelization. The second signal information includes the number of signals, signal type, time start and end point, frequency start and end point, and the signal type is radio astronomy signal or radio frequency interference.

2. A radio astronomy signal and radio frequency interference simulation method according to claim 1, characterized in that: The first signal processing is specifically a power normalization processing; The second signal processing is specifically: performing frequency domain filtering, time domain truncation, resampling and power normalization processing according to the time starting point, duration, center frequency, bandwidth and sampling rate of the measured signal; The third signal processing is specifically: frequency domain filtering, time domain truncation, resampling and frequency normalization are performed according to the time starting point, duration, center frequency, bandwidth and sampling rate of the measured signal, and down-converted to 0 Hz.

3. A radio astronomy signal and radio frequency interference simulation method according to claim 1, characterized in that: The radio astronomy signal simulation part simulates and generates fast radio burst pulse signals. The sampling rate Fs is set according to actual needs, and the center frequency of the signal f 0MHz, bandwidth BW MHz, duration T The second is generated in a random pattern or set in a fixed pattern, the dispersion of the signal DM Randomly generated or fixed configuration, where the dispersion corresponds to the interstellar medium transmission function H for: , in, D is the dispersion constant, f is the frequency, f 0- BW / 2< f < f 0+ BW / 2; Pulse signal g ( t ) in the form of a Gaussian pulse: ， in, A is the amplitude, t For the current moment, t c is the pulse center moment, and σ is the standard deviation, which is half of the Gaussian pulse width.

4. A radio astronomy signal and radio frequency interference simulation method according to claim 1, characterized in that: The radio astronomy signal and radio frequency interference are generated at that time, including the following sub-steps: S31, setting a single simulation duration of L seconds, where L should be greater than the duration T of the generated radio astronomy signal; S32, random addition of radio astronomy signals: generating a simulation addition flag for the current time according to a preset probability of occurrence of radio astronomy signals; If the add flag is 1, a signal data is randomly read from the stored alternative radio astronomy signal data file. a ( t ), randomly generate the starting time of radio astronomy signal sT 0, the signal end point is sT 1, sT 1= sT 0+ T , T is the signal duration, thereby generating a new radio astronomy signal s ( t ): ； If the add flag is 0, no radio astronomy signal will be added this time; S33, according to the set maximum number of radio frequency interference, generate the number of interferences for this mixing N , in the entire effective time-frequency space corresponding to the sampling rate Fs, randomly generate the i ( i =1,2,… N ) time-frequency range of radio frequency interference[ JT 0( i ), JT 1( i )]and[ JF 0( i ), JF 1( i )], JT 0( i )and JT 1( i ) represent the i The start and end time of the radio frequency interference, JF 0( i )and JF 1( i ) represent the i The starting and ending positions of the frequency band where the radio frequency interference is located; S34, randomly selecting a signal from the stored candidate radio frequency interference data file, reading the first signal information therein and calculating the signal bandwidth JBW ( i ), if satisfied JBW ( i )< JF 1( i )- JF 0( i ), then the signal is used as the i Baseband signal of RF interference J ( i , t )( i =1, 2, … N ), if all signal bandwidths do not meet the conditions, then regenerate [ JF 0( i ), JF 1( i )] and then re-execute this step until a RF interference baseband signal that meets the conditions is found; S35, RF interference frequency modulation: baseband signal J ( i , t )( i =1,2,… N ) to perform frequency conversion and obtain the initial RF interference Jam 0( i , t )= j ( i , t )*exp[ j 2π f c ( i ) t ],in f c ( i )= JF 0( i )+0.5 JBW ( i ); S36, RF interference power adjustment: Randomly generate interference power coefficient according to the set interference power range G i , and get the final RF interference: Jam ( i , t )= G i Jam 0( i , t ).

5. A radio astronomy signal and radio frequency interference simulation method according to claim 4, characterized in that: The antenna array simulation comprises the following sub-steps: S41, array and incident angle generation: configure array manifolds, including uniform linear arrays, circular arrays, and square arrays, and configure the number of array elements with the geometric center of the antenna array as the center. M and spacing, configuring the incident angle of the radio astronomy signal by randomly generating or fixing it ( α s , β s ) and the incident angle of the RF interference [ α J ( i ), β J ( i )]( i =1,2,… N ); S42, array signal generation: S421, perform Fourier transform on the radio astronomy signal and radio frequency interference to obtain the radio astronomy signal spectrum S ( f )=FFT( s ( t )) and RF interference spectrum Jam ( i , f )=FFT( Jam ( i , t )) ( i =1,2,… N ); For k The frequency domain response of the array element is: ， Among them τ k ( α , β ) indicates the opponent k ( x k , y k , z k ), the azimuth is α , the pitch angle is β The corresponding delay is: ， ， Thus we get the m ( m =1,2,… M ) receiving channels corresponding to the time domain signal is: x m ( t ) = FFT -1 ( X m ( f )),in, M is the total number of receiving channels; S43, signal noise: randomly generate noise level according to the set range, generate and add Gaussian white noise according to the noise level n m ( t ), the mixed signal is: x m '( t )= x m ( t )+ n m ( t ).

6. An application of a radio astronomy signal and radio frequency interference simulation method, characterized in that: The simulation method as claimed in any one of claims 1 to 5 is used for simulation to generate a test data set for system testing, and the test data set is packaged in a user-specified format according to requirements and transmitted to a back-end processing system through a network for testing.

7. An application of a radio astronomy signal and radio frequency interference simulation method, characterized in that: The simulation method as described in any one of claims 1 to 5 is used for simulation, and the data before or after channelization is subjected to short-time Fourier transform as needed to obtain two-dimensional time-frequency distribution data, and the time-frequency data is saved. At the same time, corresponding pixel-marked label data is generated according to the second signal information and saved for subsequent scientific research.

8. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, wherein: When the processor executes the program, the method according to any one of claims 1 to 5 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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