Method and equipment for processing multi-channel signals of low-orbit satellite

Abstract

The invention discloses a method and equipment for processing a multi-channel signal of a low-orbit satellite, relates to the technical field of satellite communication, and is used for solving the problems of high difficulty in realizing parallel processing of multi-channel data and high consumption of computing resources in a multi-channel carrier aggregation scene of the low-orbit satellite in related technologies. The method comprises the following steps: firstly, receiving multiple paths of baseband signals, converting the multiple paths of baseband signals from a time domain to a frequency domain through first fast Fourier transform to obtain multiple paths of frequency domain baseband data, then, carrying out up-sampling processing, up-conversion processing and carrier aggregation processing on the multiple paths of frequency domain baseband data to obtain multi-channel carrier aggregation data, and finally, carrying out up-conversion processing on the multi-channel carrier aggregation data to obtain multi-channel carrier aggregation data. And converting the multi-channel carrier aggregation data from a frequency domain to a time domain through first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal, and sending the multi-channel carrier aggregation signal to a digital front end of a receiving end. According to the embodiment of the invention, in a multi-channel carrier aggregation scene, aggregation processing of multi-channel carrier signals is realized with relatively low calculation amount and relatively low complexity.

Description

Technical Field

[0001] The present application relates to the field of satellite communication technology, and in particular to a method and device for processing multi-channel signals of a low-orbit satellite. Background Art

[0002] In low-orbit satellite communications, multi-carrier signals of multiple users are often discretely distributed in a wide frequency band. The transmitter needs to upsample and up-convert the baseband signal, and perform carrier aggregation processing with the baseband signals in multiple channels. The receiver needs to select the carrier aggregation signal within the required bandwidth from the communication frequency band, and down-convert and down-sample it to match the processing rate of the baseband. The module that undertakes the above functions is called the front end. Therefore, a communication transceiver is divided into two parts: the front end and the baseband. The front end is generally composed of an analog front end (AFE) and a digital front end (DFE), where the DFE can be regarded as a bridge between the AFE and the baseband. For example, the receiving end DFE is responsible for digital signal processing of the broadband signal received by the AFE from the antenna and sampled by analog mixing and ADC (Analog-to-digital converter), and converts it into a low-rate baseband signal required by the baseband through down-conversion, filtering and down-sampling.

[0003] The DFE processing structure commonly used in current satellite communication systems is composed of a cascade of mixing modules, variable rate sampling modules, and filtering modules. The DFE processing structure is a single-channel DFE transceiver structure based on multi-stage cascading. It can achieve a good compromise between computational complexity and signal processing quality in the process of realizing high-multiple sampling rate conversion through multi-stage sharing. Therefore, it has been widely used in single-carrier signal transmission. However, when facing a low-orbit satellite carrier aggregation scenario with a large number of channels, the above-mentioned DFE processing structure consumes huge hardware resources and places huge computational pressure when performing multi-channel parallel processing.

[0004] Therefore, related technologies have the problems of high difficulty in implementing parallel processing of multi-channel data and high consumption of computing resources in the scenario of multi-channel carrier aggregation of low-orbit satellites. Summary of the invention

[0005] The present application provides a method and device for processing multi-channel signals of a low-orbit satellite, which is used to solve the problems in the related art of high difficulty in implementing parallel processing of multi-channel data and high consumption of computing resources in the scenario of multi-channel carrier aggregation of low-orbit satellites.

[0006] In a first aspect, an embodiment of the present application provides a method for processing a multi-channel signal of a low-orbit satellite, which is applied to a digital front end of a transmitter, and the method includes:

[0007] Receiving multiple baseband signals, converting the multiple baseband signals from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data;

[0008] Performing upsampling processing, up-conversion processing, and carrier aggregation processing on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data;

[0009] The multi-channel carrier aggregation data is converted from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

[0010] In a possible implementation manner, converting the multiple baseband signals from the time domain to the frequency domain by a first fast Fourier transform to obtain multiple frequency domain baseband data includes:

[0011] For each baseband signal, perform the following operations:

[0012] Determining the number of sample points corresponding to the first fast Fourier transform of the baseband signal according to the ratio of the bandwidth of the baseband signal to the preset bandwidth;

[0013] Performing a fast Fourier transform on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

[0014] In a possible implementation manner, performing upsampling processing, up-conversion processing, and carrier aggregation processing on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data includes:

[0015] For each channel of frequency domain baseband data, perform the following operations:

[0016] The frequency domain baseband data is used as the low-frequency part, and 0 is added to the preset N points in the high-frequency direction to obtain up-sampled data;

[0017] Determine the frequency point corresponding to the frequency band center of the up-sampled data and the target number of shift points according to the target carrier frequency required for up-conversion and the preset carrier frequency of the baseband signal corresponding to the up-sampled data; take the frequency point corresponding to the frequency band center of the up-sampled data as a reference point, shift the up-sampled data as a whole by the target number of shift points to obtain the up-converted data;

[0018] The obtained frequency conversion data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

[0019] In a possible implementation manner, converting the multi-channel carrier aggregation data from the frequency domain to the time domain by a first inverse fast Fourier transform to obtain a carrier aggregation signal includes:

[0020] The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

[0021] In a possible implementation manner, before converting the multi-channel baseband signals from the time domain to the frequency domain by the first fast Fourier transform, the method further includes:

[0022] A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is filtered using the low-pass filter.

[0023] In a second aspect, an embodiment of the present application provides a method for processing a multi-channel signal of a low-orbit satellite, which is applied to a digital front end of a receiving end, and the method includes:

[0024] receiving a multi-channel carrier aggregation signal, and converting the multi-channel carrier aggregation signal from a time domain to a frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data;

[0025] Performing down-conversion and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data;

[0026] The multi-channel frequency domain baseband data is converted from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multi-channel baseband signal.

[0027] In a possible implementation manner, converting the multi-channel carrier aggregation signal from the time domain to the frequency domain by a second fast Fourier transform to obtain multi-channel carrier aggregation data includes:

[0028] The multi-channel carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

[0029] In a possible implementation manner, performing down-conversion processing and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data includes:

[0030] Performing multiple down-conversion processes and multiple down-sampling processes on the multi-channel carrier aggregation data to obtain multiple down-sampled data;

[0031] The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data; for each down-conversion process and each down-sampling process, the following operations are performed respectively:

[0032] Determine the frequency point and the target number of shift points corresponding to the target frequency band center of the multiple frequency domain baseband data in the current down-conversion process according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal; the baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal;

[0033] Taking the frequency point corresponding to the center of the target frequency band as a reference point, the multi-channel carrier aggregation data is overall shifted by the target shift point number to obtain down-converted data;

[0034] The number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the number of sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

[0035] In a possible implementation manner, converting the multiple frequency domain baseband data from the frequency domain to the time domain by a second inverse fast Fourier transform to obtain multiple baseband signals includes:

[0036] For each channel of frequency domain baseband data, perform the following operations:

[0037] Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth;

[0038] Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain a baseband signal.

[0039] In a possible implementation manner, after obtaining the multiple baseband signals, the method further includes:

[0040] A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is processed by using the low-pass filter.

[0041] In a third aspect, an embodiment of the present application provides a low-orbit satellite multi-channel signal processing device, which is applied to a transmitting end digital front end, and the device includes:

[0042] A first Fourier transform module is configured to receive multiple baseband signals, and convert the multiple baseband signals from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data;

[0043] A multi-channel frequency domain baseband data processing module is configured to perform up-sampling processing, up-conversion processing and carrier aggregation processing on the multi-channel frequency domain baseband data to obtain multi-channel carrier aggregation data;

[0044] The first inverse Fourier transform module is configured to convert the multi-channel carrier aggregation data from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

[0045] In a possible implementation manner, the step of converting the multiple baseband signals from the time domain to the frequency domain by using the first fast Fourier transform to obtain multiple frequency domain baseband data is performed, and the first Fourier transform module is configured as follows:

[0046] For each baseband signal, perform the following operations:

[0047] Determining the number of sample points corresponding to the first fast Fourier transform of the baseband signal according to the ratio of the bandwidth of the baseband signal to the preset bandwidth;

[0048] Performing a fast Fourier transform on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

[0049] In a possible implementation manner, the upsampling processing, up-conversion processing, and carrier aggregation processing are performed on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data, and the multiple frequency domain baseband data processing module is configured as follows:

[0050] For each channel of frequency domain baseband data, perform the following operations:

[0051] The frequency domain baseband data is used as the low-frequency part, and 0 is added to the preset N points in the high-frequency direction to obtain up-sampled data;

[0052] Determine the frequency point corresponding to the frequency band center of the up-sampled data and the target number of shift points according to the target carrier frequency required for up-conversion and the preset carrier frequency of the baseband signal corresponding to the up-sampled data; take the frequency point corresponding to the frequency band center of the up-sampled data as a reference point, shift the up-sampled data as a whole by the target number of shift points to obtain the up-converted data;

[0053] The obtained frequency conversion data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

[0054] In a possible implementation manner, the converting of the multi-channel carrier aggregation data from the frequency domain to the time domain by a first inverse fast Fourier transform to obtain a carrier aggregation signal is performed, and the first inverse Fourier transform module is configured as follows:

[0055] The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

[0056] In a possible implementation manner, before converting the multi-channel baseband signals from the time domain to the frequency domain through the first fast Fourier transform, the apparatus further includes:

[0057] The first filtering module is configured to determine a low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to filter the baseband signal.

[0058] In a fourth aspect, an embodiment of the present application provides a low-orbit satellite multi-channel signal processing device, which is applied to a receiving end digital front end, and the device includes:

[0059] A second Fourier transform module is configured to receive a multi-channel carrier aggregation signal, and convert the multi-channel carrier aggregation signal from the time domain to the frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data;

[0060] A multi-channel carrier aggregation data processing module is configured to perform down-conversion processing and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data;

[0061] The second inverse Fourier transform module is configured to convert the multiple frequency domain baseband data from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain multiple baseband signals.

[0062] In a possible implementation manner, the converting of the multi-channel carrier aggregation signal from the time domain to the frequency domain by a second fast Fourier transform to obtain multi-channel carrier aggregation data is performed, and the second Fourier transform module is configured as follows:

[0063] The multi-channel carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

[0064] In a possible implementation manner, the down-conversion processing and down-sampling processing are performed on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data, and the multi-channel carrier aggregation data processing module is configured as follows:

[0065] Performing multiple down-conversion processes and multiple down-sampling processes on the multi-channel carrier aggregation data to obtain multiple down-sampled data;

[0066] The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data;

[0067] For each down-conversion process and each down-sampling process, the following operations are performed respectively:

[0068] Determine the frequency point and the target number of shift points corresponding to the target frequency band center of the multiple frequency domain baseband data in the current down-conversion process according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal; the baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal;

[0069] Taking the frequency point corresponding to the center of the target frequency band as a reference point, the multi-channel carrier aggregation data is overall shifted by the target shift point number to obtain down-converted data;

[0070] The number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the number of sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

[0071] In a possible implementation manner, the step of converting the multiple frequency domain baseband data from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multiple baseband signal is performed, and the second inverse Fourier transform module is configured as follows:

[0072] For each channel of frequency domain baseband data, perform the following operations:

[0073] Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth;

[0074] Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain a baseband signal.

[0075] In a possible implementation manner, after obtaining the multiple baseband signals, the device further includes:

[0076] The second filtering module is configured to determine a low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to process the baseband signal.

[0077] In a fifth aspect, an embodiment of the present application further provides an electronic device, including:

[0078] Memory and processor;

[0079] The memory is used to store the processor executable instructions;

[0080] The processor is configured to execute the instructions to implement the method for processing low-orbit satellite multi-channel signals described in the first and second aspects above.

[0081] In the sixth aspect, an embodiment of the present invention further provides a computer-readable storage medium. When the instructions in the computer-readable storage medium are executed by the processor of the device, the device is able to execute the method for processing low-orbit satellite multi-channel signals described in the first and second aspects above.

[0082] The beneficial effects of the embodiments of the present application are as follows: when facing a low-orbit satellite carrier aggregation scenario with a large number of channels, the embodiments of the present application perform fast Fourier transform processing on multi-channel carrier signals, and convert the calculation process of time domain data at the receiving end and the transmitting end into a calculation process of frequency domain data, thereby realizing aggregation processing of multi-channel carrier signals with lower computational complexity and lower complexity, meeting the multi-channel transmission requirements of carrier aggregation and non-uniform channelized reception in non-continuous frequency bands, meeting the real-time processing requirements of multi-channel data of low-orbit satellites, improving data transmission efficiency, and saving hardware resources.

[0083] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings introduced below are only some embodiments of the present application.

[0085] Figure 1 A schematic diagram of an application framework of a method for processing multi-channel signals of a low-orbit satellite provided in an embodiment of the present application;

[0086] Figure 2 A flowchart of a method for processing a multi-channel signal of a low-orbit satellite applied to a digital front end of a transmitter provided in an embodiment of the present application;

[0087] Figure 3 A schematic diagram of a first fast Fourier transform process provided in an embodiment of the present application;

[0088] Figure 4 A schematic diagram of a process for upsampling, up-converting, and carrier aggregation of multiple frequency domain baseband data provided in an embodiment of the present application;

[0089] Figure 5 A flowchart of a method for processing a multi-channel signal of a low-orbit satellite applied to a receiving-end digital front end provided in an embodiment of the present application;

[0090] Figure 6A schematic diagram of a process for down-converting and down-sampling multi-channel carrier aggregation data provided in an embodiment of the present application;

[0091] Figure 7 A schematic diagram of the structure of a low-orbit satellite multi-channel signal processing device 700 provided in an embodiment of the present application;

[0092] Figure 8 A schematic diagram of the structure of a low-orbit satellite multi-channel signal processing device 800 provided in an embodiment of the present application;

[0093] Fig. 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0094] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Among them, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0095] Furthermore, in the description of the embodiments of the present application, unless otherwise specified, “ / ” means or. For example, A / B can mean A or B. The “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0096] In low-orbit satellite communications, multi-carrier signals of multiple users are often discretely distributed in a wide frequency band. The transmitter needs to upsample and up-convert the baseband signal, and perform carrier aggregation processing with the baseband signals in multiple channels. The receiver needs to select the carrier aggregation signal within the required bandwidth from the communication frequency band, and down-convert and down-sample it to match the processing rate of the baseband. The module that undertakes the above functions is called the front end. Therefore, a communication transceiver is divided into two parts: the front end and the baseband. The front end is generally composed of an analog front end (AFE) and a digital front end (DFE), where the DFE can be regarded as a bridge between the AFE and the baseband. For example, the receiving end DFE is responsible for digital signal processing of the broadband signal received by the AFE from the antenna after analog mixing and ADC sampling, and converts it into a low-rate baseband signal required by the baseband through down-conversion, filtering and down-sampling.

[0097] The DFE processing structure commonly used in current satellite communication systems is composed of a mixing module, a variable rate sampling module, and a filtering module in cascade. The related technology includes the following DFE processing structures:

[0098] 1. A DFE transmitter using a 4x upsampling, a root raised cosine (RRC) filter, and a digital intermediate frequency sampling structure, and a DFE receiver using a symmetrical structure, can achieve 4x sampling rate conversion of any baseband bandwidth.

[0099] 2. A low-orbit satellite digital up-converter based on multi-stage interpolation. The transmitting end DFE model consists of a shaping filter, a 2-stage half-band filter, a 4-stage cascaded integrator comb (CIC) interpolation filter and a direct digital synthesizer (DDS) mixer, which can achieve 40 times the sampling rate conversion.

[0100] 3. A DFE transmitter using a cascade of RRC shaping filter, a 2-stage half-band filter, a 2-stage FIR interpolator (2x, 5x) and a complex multiplication mixer can achieve 80x sampling rate conversion.

[0101] 4. A broadband DFE receiver based on DDS mixing, 11x CIC decimation filtering and FIR low-pass filtering structure.

[0102] The above-mentioned DFE processing structure is a single-channel DFE transceiver structure based on multi-stage cascading. It can achieve a good compromise between computational complexity and signal processing quality in the process of realizing high-multiple sampling rate conversion through multi-stage sharing. Therefore, it has been widely used in single-carrier signal transmission. However, when facing a low-orbit satellite carrier aggregation scenario with a large number of channels, the above-mentioned DFE processing structure consumes huge hardware resources and places huge computational pressure when performing multi-channel parallel processing.

[0103] Therefore, related technologies have the problems of high difficulty in implementing parallel processing of multi-channel data and high consumption of computing resources in the scenario of multi-channel carrier aggregation of low-orbit satellites.

[0104] In view of this, the present application provides a method and device for processing multi-channel signals of low-orbit satellites, which is used to solve the problems in the related art of high difficulty in implementing parallel processing of multi-channel data and high consumption of computing resources in the scenario of multi-channel carrier aggregation of low-orbit satellites.

[0105] The inventive concept of the present application can be summarized as follows: first, multiple baseband signals are received, and the multiple baseband signals are converted from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data; then, the multiple frequency domain baseband data are upsampled, up-converted, and carrier aggregated to obtain multi-channel carrier aggregation data; finally, the multi-channel carrier aggregation data is converted from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving digital front end.

[0106] In summary, when facing a low-orbit satellite carrier aggregation scenario with a large number of channels, the embodiments of the present application perform fast Fourier transform processing on the multi-channel carrier signals, and convert the calculation process of the time domain data of the receiving end and the transmitting end into the calculation process of the frequency domain data. Aggregation processing of multi-channel carrier signals is achieved with lower computational complexity and lower complexity, which meets the multi-channel transmission requirements of carrier aggregation and non-uniform channelized reception in non-continuous frequency bands, meets the real-time processing requirements of multi-channel data of low-orbit satellites, improves data transmission efficiency, and saves hardware resources.

[0107] To further illustrate the technical solution provided by the embodiment of the present application, this is described in detail below in conjunction with the accompanying drawings and specific implementation methods. Although the embodiment of the present application provides the method operation steps as shown in the following embodiments or drawings, more or fewer operation steps may be included in the method based on routine or no creative labor. In the steps where there is no necessary causal relationship logically, the execution order of these steps is not limited to the execution order provided by the embodiment of the present application. It should be noted that all position information in the embodiments of the present application refers to the position information in the geocentric inertial coordinate system.

[0108] See also Figure 1 , which is a schematic diagram of the application framework of a method for processing multi-channel signals of a low-orbit satellite provided in an embodiment of the present application. At the transmitting end, the digital front end receives multi-channel baseband signals, performs Fourier transform, up-sampling, up-conversion and carrier aggregation processing on the multi-channel baseband signals to obtain multi-channel carrier aggregation data, and then performs inverse Fourier transform processing on the multi-channel carrier aggregation data to obtain a multi-channel carrier aggregation signal, and finally the multi-channel carrier aggregation signal is processed by DAC (Digital-to-analog converter) and AFE to complete the wireless signal transmission; at the receiving end, the wireless signal is processed by AFE and ADC to obtain a multi-channel carrier aggregation signal, and the digital front end performs Fourier transform, down-sampling and down-conversion processing on the multi-channel carrier aggregation signal to obtain multi-channel frequency domain baseband data, and then performs inverse Fourier transform processing on the multi-channel frequency domain baseband data to obtain a multi-channel baseband signal, and finally the multi-channel baseband signal is sent to the baseband. It should be noted that the above Figure 1The transmitter and receiver shown in the figure belong to the same low-orbit satellite, and the multi-channel carrier aggregation signal emitted by the transmitter and the multi-channel carrier aggregation signal received by the receiver are not the same signal.

[0109] In a possible implementation manner, the present application embodiment provides a method for processing a multi-channel signal of a low-orbit satellite, which is applied to a digital front end of a transmitter, and the process is as follows: Figure 2 As shown, the following steps are included:

[0110] In step 201, multiple baseband signals are received, and the multiple baseband signals are converted from the time domain to the frequency domain by a first fast Fourier transform to obtain multiple frequency domain baseband data.

[0111] In a possible implementation, the multi-channel baseband signals are converted from the time domain to the frequency domain by a first fast Fourier transform to obtain multi-channel frequency domain baseband data. The process is as follows: Figure 3 As shown, it can be implemented as:

[0112] For each baseband signal, perform the following operations:

[0113] In step 301, the number of sample points corresponding to the first fast Fourier transform of the baseband signal is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth.

[0114] In step 302, a fast Fourier transform is performed on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

[0115] For example, the five baseband signal bandwidths shown in Table 1 below may correspond to a certain number of sample points M k Value

[0116] Table 1

[0117]

[0118]

[0119] For example, if the preset bandwidth is 5.2 kHz and the bandwidth of the baseband signal is 10.4 kHz, the embodiment of the present application can determine the number of sample points M corresponding to the first fast Fourier transform. k is 32.

[0120] In step 202, up-sampling processing, up-conversion processing and carrier aggregation processing are performed on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data.

[0121] In a possible implementation manner, up-sampling processing, up-conversion processing, and carrier aggregation processing are performed on multiple frequency domain baseband data to obtain multi-channel carrier aggregation data, such as Figure 4 As shown, it can be implemented as:

[0122] For each channel of frequency domain baseband data, perform the following operations:

[0123] In step 401, the frequency domain baseband data is used as the low-frequency part, and 0 is padded to a preset N points in the high-frequency direction to obtain up-sampled data.

[0124] In step 402, the frequency point corresponding to the frequency band center of the upsampled data and the target shift point number are determined based on the target carrier frequency required for upconversion and the preset carrier frequency of the baseband signal corresponding to the upsampled data; the frequency point corresponding to the frequency band center of the upsampled data is used as a reference point, and the upsampled data is shifted as a whole by the target shift point number to obtain the upconverted data.

[0125] In step 403, the obtained frequency-converted data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

[0126] It should be noted that for baseband signals of different paths, the target carrier frequency and the preset carrier frequency required for up-conversion may be different. The frequency band center of the above up-sampled data is the preset carrier frequency of the baseband signal corresponding to the up-sampled data.

[0127] In step 203, the multi-channel carrier aggregation data is converted from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

[0128] In a possible implementation, converting multi-channel carrier aggregation data from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a carrier aggregation signal can be implemented as follows:

[0129] The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

[0130] In one possible implementation, before converting multiple baseband signals from the time domain to the frequency domain through the first fast Fourier transform, the embodiment of the present application will also determine the low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to filter the baseband signal.

[0131] In another possible implementation, the present application embodiment provides a method for processing a low-orbit satellite multi-channel signal, which is applied to a receiving end digital front end, and the process is as follows: Figure 5 As shown, the following steps are included:

[0132] In step 501, a multi-channel carrier aggregation signal is received, and the multi-channel carrier aggregation signal is converted from the time domain to the frequency domain by a second fast Fourier transform to obtain multi-channel carrier aggregation data.

[0133] In a possible implementation, converting the multi-channel carrier aggregation signal from the time domain to the frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data can be implemented as follows:

[0134] A fast Fourier transform is performed on the multi-channel carrier aggregation signal according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

[0135] It should be noted that the multi-channel carrier aggregation signal received by the digital front end of the receiver comes from another low-orbit satellite, and the number of sample points corresponding to the second fast Fourier transform is the same as the number of sample points corresponding to the first inverse fast Fourier transform, both of which are preset N points.

[0136] In step 502, down-conversion processing and down-sampling processing are performed on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data.

[0137] In a possible implementation, down-conversion and down-sampling are performed on multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data, which can be implemented as follows:

[0138] Performing multiple down-conversion processing and multiple down-sampling processing on the multi-channel carrier aggregation data to obtain multiple down-sampled data;

[0139] The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data.

[0140] It should be added that if the multi-channel carrier aggregation data is aggregated by M carrier data at the digital front end of the transmitter, the embodiment of the present application performs M down-conversion processing and M down-sampling processing on the multi-channel carrier aggregation data at the digital front end of the receiver, and the M down-sampled data obtained will be used as multi-channel frequency domain baseband data.

[0141] For each down-conversion process and each down-sampling process, the process is as follows: Figure 6 As shown, perform the following operations respectively:

[0142] In step 601, the frequency point and the target number of shift points corresponding to the target frequency band center of the multi-channel frequency domain baseband data in the current down-conversion process are determined according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal.

[0143] The baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal. For example, the baseband signal A is any one of the multiple baseband signals, and the target carrier frequency required for up-conversion of the baseband signal A is f A , the original preset carrier frequency of the baseband signal A is f0. In the process of down-converting the multi-channel carrier aggregation data, the target frequency band center of the multi-channel frequency domain baseband data is f0. The embodiment of the present application is based on f A and f0 determine the number of target translation points.

[0144] In step 602, the frequency point corresponding to the center of the target frequency band is used as a reference point, and the multi-channel carrier aggregation data is shifted as a whole by the target shift point number to obtain down-converted data.

[0145] In step 603, the number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

[0146] In step 503, the multi-channel frequency domain baseband data is converted from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multi-channel baseband signal.

[0147] In a possible implementation, the multi-channel frequency domain baseband data is converted from the frequency domain to the time domain by a second inverse fast Fourier transform to obtain a multi-channel baseband signal, which can be implemented as follows:

[0148] For each channel of frequency domain baseband data, perform the following operations:

[0149] Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth;

[0150] Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain the baseband signal.

[0151] In a possible implementation, after obtaining multiple baseband signals, the embodiment of the present application will also determine the low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to process the baseband signal.

[0152] Below is the K-based signal Taking the example, the specific process of the method for processing multi-channel signals of low-orbit satellites provided in the embodiment of the present application is described:

[0153] 1. At the transmitter, the DFE module needs to input K (1≤K) roadband signals Perform upsampling, upconversion and carrier aggregation. Suppose the sampling rate of the Kth baseband signal is In the embodiment of the present application, it is assumed that the baseband signal input to the DFE has completed RRC shaping filtering at the baseband, but when using the application, the shaping filtering process can also be incorporated into the DFE for implementation according to specific needs.

[0154] 2. Baseband signal First, the current signal bandwidth W k The corresponding low-pass filter LPF k , in order to improve the out-of-band attenuation performance of the baseband signal so that it meets the required adjacent channel power ratio. Since the bandwidth of the baseband signal to be transmitted is W k They are usually clear and limited in type, so when performing LPF operations, they can be based on W k Option to load pre-designed FIR filter coefficients.

[0155] 3. Baseband signal after low-pass filtering According to the number of processing points (i.e. sample points) required, each M k (1≤k≤K) points to perform an FFT and obtain the Kth path M k Point frequency domain baseband data

[0156] 4. The Kth frequency domain baseband data As the low-frequency part, points 0 to N are filled in the high-frequency direction to achieve R x times upsampling, upsampling multiple R x =N / M k The value of N should be as large as possible within the hardware implementation capability to improve the frequency resolution of frequency domain processing. The high frequency is padded with 0 and the up-sampled data is and The conversion relationship is as follows:

[0157] if M k odd:

[0158]

[0159] if M k even:

[0160]

[0161] By filling 0 to N points at high frequencies for K-channel frequency domain baseband data, the sampling rate of K-channel frequency domain baseband data is also unified to It should be noted that this application recommends the above results Apply R x times the gain in order to recover the power scaling due to upsampling.

[0162] 5. Upsample data after high frequency zero padding Perform circular translation to translate the frequency point corresponding to the frequency band center of the up-sampled data to the frequency point corresponding to the preset carrier frequency corresponding to the baseband signal f k At this point, frequency domain up-conversion of the Kth frequency domain baseband data is realized, and the output is up-converted data The circular translation processing formula for frequency domain up-conversion is as follows:

[0163]

[0164] Among them, mod(x,y) represents the modulus operation of x on y. The number of points for the K-th data to be circularly shifted to the right. A negative value indicates a circular left shift. round(·) means rounding to the nearest integer.

[0165] 6. Convert the frequency data on K channels Add by frequency point to get multi-channel carrier aggregation data

[0166] 7. Yes An N-point IFFT is performed to finally obtain the time domain signal after N-point carrier aggregation (i.e., multi-channel carrier aggregation signal) as the output of the DFE module, which is then processed by DAC and AFE to complete the wireless signal transmission.

[0167] 8. At the receiving end, the wireless signal is processed by AFE and sampled by ADC to obtain the input signal s of the DFE module. r , sampling rate For r FFT is performed once for every N points according to the number of sample points to obtain N-point frequency domain data (ie, multi-channel carrier aggregation data) Sr[n] (0≤n≤N-1).

[0168] 9. Use the preset carrier frequency f corresponding to the Kth baseband signal k Determine the target translation points as follows:

[0169]

[0170] The frequency point corresponding to the frequency band center of the frequency domain carrier aggregation data is shifted by the target shift point number to obtain the down-converted data (i.e., frequency domain baseband data) corresponding to the Kth baseband signal, as shown in the following formula:

[0171]

[0172] Among them, mod(x,y) represents the modulus operation of x on y. The number of points for the K-th data to be circularly shifted to the right. A negative value indicates a circular left shift. round(·) means rounding to the nearest integer.

[0173] 10. According to the bandwidth W of the K-th baseband signal k Look up the table to determine the corresponding FFT / IFFT point number M k (The corresponding relationship is the same as that of the transmitting end DFE, as shown in Table 1 above), Both ends M k The low-frequency part within the point is retained, and M k The high frequency part outside the point is discarded to obtain Do D k =N / M k Downsampled data by times The corresponding data sampling rate also becomes and The conversion relationship is as follows:

[0174] if M k odd:

[0175]

[0176] if M k even:

[0177]

[0178] 11. For the K-th frequency domain baseband data Execute M k Point IFFT, get the Kth channel M with low sampling rate k Point time domain baseband signal

[0179] 12. According to the Kth Road M k Point time domain baseband signal W k Load the corresponding FIR low-pass filter coefficients and pass the low-pass filter LPF k Realize the suppression of out-of-band noise and interference of time domain baseband signal, FIR filtering output data As the output of the DFE module, it is passed to the baseband for subsequent reception processing.

[0180] To summarize, when facing a low-orbit satellite carrier aggregation scenario with a large number of channels, the embodiments of the present application perform fast Fourier transform processing on multi-channel carrier signals, and convert the calculation process of time domain data at the receiving end and the transmitting end into a calculation process of frequency domain data, thereby realizing aggregation processing of multi-channel carrier signals with lower computational complexity and lower complexity, meeting the multi-channel transmission requirements of carrier aggregation and non-uniform channelized reception in non-continuous frequency bands, meeting the real-time processing requirements of multi-channel data of low-orbit satellites, improving data transmission efficiency, and saving hardware resources.

[0181] Based on the same inventive concept, the embodiment of the present application also provides a processing device for low-orbit satellite multi-channel signals, which is applied to the digital front end of the transmitter, such as Figure 7 As shown, the device 700 includes:

[0182] The first Fourier transform module 701 is configured to receive multiple baseband signals, and convert the multiple baseband signals from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data;

[0183] The multi-channel frequency domain baseband data processing module 702 is configured to perform up-sampling processing, up-conversion processing and carrier aggregation processing on the multi-channel frequency domain baseband data to obtain multi-channel carrier aggregation data;

[0184] The first inverse Fourier transform module 703 is configured to convert the multi-channel carrier aggregation data from the frequency domain to the time domain through a first inverse fast Fourier transform, obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

[0185] In a possible implementation manner, the step of converting the multiple baseband signals from the time domain to the frequency domain by using the first fast Fourier transform to obtain multiple frequency domain baseband data is performed, and the first Fourier transform module is configured as follows:

[0186] For each baseband signal, perform the following operations:

[0187] Determining the number of sample points corresponding to the first fast Fourier transform of the baseband signal according to the ratio of the bandwidth of the baseband signal to the preset bandwidth;

[0188] Performing a fast Fourier transform on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

[0189] In a possible implementation manner, the upsampling processing, up-conversion processing, and carrier aggregation processing are performed on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data, and the multiple frequency domain baseband data processing module is configured as follows:

[0190] For each channel of frequency domain baseband data, perform the following operations:

[0191] The frequency domain baseband data is used as the low-frequency part, and 0 is added to the preset N points in the high-frequency direction to obtain up-sampled data;

[0192] Determine the frequency point corresponding to the frequency band center of the up-sampled data and the target number of shift points according to the target carrier frequency required for up-conversion and the preset carrier frequency of the baseband signal corresponding to the up-sampled data; take the frequency point corresponding to the frequency band center of the up-sampled data as a reference point, shift the up-sampled data as a whole by the target number of shift points to obtain the up-converted data;

[0193] The obtained frequency conversion data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

[0194] In a possible implementation manner, the converting of the multi-channel carrier aggregation data from the frequency domain to the time domain by a first inverse fast Fourier transform to obtain a carrier aggregation signal is performed, and the first inverse Fourier transform module is configured as follows:

[0195] The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

[0196] In a possible implementation manner, before converting the multi-channel baseband signals from the time domain to the frequency domain through the first fast Fourier transform, the apparatus further includes:

[0197] The first filtering module is configured to determine a low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to filter the baseband signal.

[0198] Based on the same inventive concept, the embodiment of the present application also provides a processing device for low-orbit satellite multi-channel signals, which is applied to a receiving end digital front end, such as Figure 8 As shown, the device 800 includes:

[0199] The second Fourier transform module 801 is configured to receive a multi-channel carrier aggregation signal, and convert the multi-channel carrier aggregation signal from the time domain to the frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data;

[0200] The multi-channel carrier aggregation data processing module 802 is configured to perform down-conversion processing and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data;

[0201] The second inverse Fourier transform module 803 is configured to convert the multiple frequency domain baseband data from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain multiple baseband signals.

[0202] In a possible implementation manner, the converting of the multi-channel carrier aggregation signal from the time domain to the frequency domain by a second fast Fourier transform to obtain multi-channel carrier aggregation data is performed, and the second Fourier transform module is configured as follows:

[0203] The multi-channel carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

[0204] In a possible implementation manner, the down-conversion processing and down-sampling processing are performed on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data, and the multi-channel carrier aggregation data processing module is configured as follows:

[0205] Performing multiple down-conversion processes and multiple down-sampling processes on the multi-channel carrier aggregation data to obtain multiple down-sampled data;

[0206] The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data;

[0207] For each down-conversion process and each down-sampling process, the following operations are performed respectively:

[0208] Determine the frequency point and the target number of shift points corresponding to the target frequency band center of the multiple frequency domain baseband data in the current down-conversion process according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal; the baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal;

[0209] Taking the frequency point corresponding to the center of the target frequency band as a reference point, the multi-channel carrier aggregation data is overall shifted by the target shift point number to obtain down-converted data;

[0210] The number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the number of sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

[0211] In a possible implementation manner, the step of converting the multiple frequency domain baseband data from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multiple baseband signal is performed, and the second inverse Fourier transform module is configured as follows:

[0212] For each channel of frequency domain baseband data, perform the following operations:

[0213] Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth;

[0214] Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain a baseband signal.

[0215] In a possible implementation manner, after obtaining the multiple baseband signals, the device further includes:

[0216] The second filtering module is configured to determine a low-pass filter corresponding to each baseband signal according to the bandwidth of each baseband signal, and use the low-pass filter to process the baseband signal.

[0217] Based on the same inventive concept as the embodiment of the present application, the embodiment of the present application provides the following Fig. 9 An electronic device as shown, Fig. 9 As shown, it includes: a processor 901, a communication interface 902, a memory 903 and a communication bus 904, wherein the processor 901, the communication interface 902, and the memory 903 communicate with each other through the communication bus 904;

[0218] The memory 903 stores a computer program. When the program is executed by the processor 901, the processor 901 performs the following steps:

[0219] Receiving multiple baseband signals, converting the multiple baseband signals from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data;

[0220] Performing upsampling processing, up-conversion processing, and carrier aggregation processing on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data;

[0221] The multi-channel carrier aggregation data is converted from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

[0222] In a possible implementation, the processor 901 performs the following steps:

[0223] For each baseband signal, perform the following operations:

[0224] Determining the number of sample points corresponding to the first fast Fourier transform of the baseband signal according to the ratio of the bandwidth of the baseband signal to the preset bandwidth;

[0225] Performing a fast Fourier transform on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

[0226] In a possible implementation, the processor 901 performs the following steps:

[0227] For each channel of frequency domain baseband data, perform the following operations:

[0228] The frequency domain baseband data is used as the low-frequency part, and 0 is added to the preset N points in the high-frequency direction to obtain up-sampled data;

[0229] Determine the frequency point corresponding to the frequency band center of the up-sampled data and the target number of shift points according to the target carrier frequency required for up-conversion and the preset carrier frequency of the baseband signal corresponding to the up-sampled data; take the frequency point corresponding to the frequency band center of the up-sampled data as a reference point, shift the up-sampled data as a whole by the target number of shift points to obtain the up-converted data;

[0230] The obtained frequency conversion data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

[0231] In a possible implementation, the processor 901 performs the following steps:

[0232] The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

[0233] In a possible implementation, the processor 901 performs the following steps:

[0234] A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is filtered using the low-pass filter.

[0235] The electronic device is a receiving digital front end, and the processor 901 performs the following steps:

[0236] receiving a multi-channel carrier aggregation signal, and converting the multi-channel carrier aggregation signal from a time domain to a frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data;

[0237] Performing down-conversion and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data;

[0238] The multi-channel frequency domain baseband data is converted from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multi-channel baseband signal.

[0239] In a possible implementation, the processor 901 performs the following steps:

[0240] The multi-channel carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

[0241] In a possible implementation, the processor 901 performs the following steps:

[0242] Performing multiple down-conversion processes and multiple down-sampling processes on the multi-channel carrier aggregation data to obtain multiple down-sampled data;

[0243] The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data;

[0244] For each down-conversion process and each down-sampling process, the following operations are performed respectively:

[0245] Determine the frequency point and the target number of shift points corresponding to the target frequency band center of the multiple frequency domain baseband data in the current down-conversion process according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal; the baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal;

[0246] Taking the frequency point corresponding to the center of the target frequency band as a reference point, the multi-channel carrier aggregation data is overall shifted by the target shift point number to obtain down-converted data;

[0247] The number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the number of sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

[0248] In a possible implementation, the processor 901 performs the following steps:

[0249] For each channel of frequency domain baseband data, perform the following operations:

[0250] Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth;

[0251] Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain a baseband signal.

[0252] In a possible implementation, the processor 901 performs the following steps:

[0253] A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is processed by using the low-pass filter.

[0254] The communication bus mentioned in the above electronic device can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus. The communication interface 902 is used for communication between the above electronic device and other devices. The memory may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor. The above processor may be a general-purpose processor, including a central processing unit, a network processor (NP), etc.; it may also be a digital signal processing processor (DSP), an application-specific integrated circuit, a field programmable gate array or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc.

[0255] On the basis of the above embodiments, the present application further provides a computer-readable storage medium, such as a memory including instructions, and the above instructions can be executed by a processor to complete the above-mentioned low-orbit satellite multi-channel signal processing method. Optionally, the storage medium can be a non-temporary computer-readable storage medium, for example, the non-temporary computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device.

[0256] Since the principle of solving the problem by the computer-readable medium provided above is similar to the method for processing multi-channel signals of low-orbit satellites, after the processor executes the computer program in the computer-readable medium above, the steps implemented can be referred to the above embodiment, and the repeated parts will not be repeated.

[0257] Based on the above embodiments, the present application also provides a computer program product, including a computer program, which, when executed by a processor, implements any method of processing low-orbit satellite multi-channel signals as provided in the present application.

[0258] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0259] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0260] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0261] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0262] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. These modifications and variations of the present application belong to the scope of the claims of the present application and their equivalents.

Claims

1. A method for processing multi-channel signals of a low-orbit satellite, characterized in that: Applied to a digital front end of a transmitter, the method comprises: Receiving multiple baseband signals, converting the multiple baseband signals from the time domain to the frequency domain through a first fast Fourier transform to obtain multiple frequency domain baseband data; Performing upsampling processing, up-conversion processing, and carrier aggregation processing on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data; The multi-channel carrier aggregation data is converted from the frequency domain to the time domain through a first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal and send the multi-channel carrier aggregation signal to a receiving end digital front end.

2. The method according to claim 1, characterized in that The method of converting the multi-channel baseband signals from the time domain to the frequency domain by a first fast Fourier transform to obtain multi-channel frequency domain baseband data comprises: For each baseband signal, perform the following operations: Determining the number of sample points corresponding to the first fast Fourier transform of the baseband signal according to the ratio of the bandwidth of the baseband signal to the preset bandwidth; Performing a fast Fourier transform on the baseband signal according to the number of sample points to obtain frequency domain baseband data.

3. The method according to claim 2, characterized in that The performing upsampling processing, up-conversion processing and carrier aggregation processing on the multiple frequency domain baseband data to obtain multi-channel carrier aggregation data includes: For each channel of frequency domain baseband data, perform the following operations: The frequency domain baseband data is used as the low-frequency part, and 0 is added to the preset N points in the high-frequency direction to obtain up-sampled data; Determine the frequency point corresponding to the frequency band center of the up-sampled data and the target number of shift points according to the target carrier frequency required for up-conversion and the preset carrier frequency of the baseband signal corresponding to the up-sampled data; take the frequency point corresponding to the frequency band center of the up-sampled data as a reference point, shift the up-sampled data as a whole by the target number of shift points to obtain the up-converted data; The obtained frequency conversion data on multiple channels are added according to the frequency points to obtain multi-channel carrier aggregation data.

4. The method according to claim 1, characterized in that The converting the multi-channel carrier aggregation data from the frequency domain to the time domain by a first inverse fast Fourier transform to obtain a carrier aggregation signal includes: The carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the first inverse fast Fourier transform to obtain a multi-channel carrier aggregation signal; the number of sample points corresponding to the first inverse fast Fourier transform is a preset N point.

5. The method according to claim 1, characterized in that Before converting the multi-channel baseband signals from the time domain to the frequency domain by a first fast Fourier transform, the method further comprises: A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is filtered using the low-pass filter.

6. A method for processing multi-channel signals of a low-orbit satellite, characterized in that: Applied to a receiving end digital front end, the method comprises: receiving a multi-channel carrier aggregation signal, and converting the multi-channel carrier aggregation signal from a time domain to a frequency domain through a second fast Fourier transform to obtain multi-channel carrier aggregation data; Performing down-conversion and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data; The multi-channel frequency domain baseband data is converted from the frequency domain to the time domain through a second inverse fast Fourier transform to obtain a multi-channel baseband signal.

7. The method according to claim 6, characterized in that The converting the multi-channel carrier aggregation signal from the time domain to the frequency domain by a second fast Fourier transform to obtain multi-channel carrier aggregation data includes: The multi-channel carrier aggregation signal is subjected to a fast Fourier transform according to the number of sample points corresponding to the second fast Fourier transform to obtain multi-channel carrier aggregation data; the number of sample points corresponding to the second fast Fourier transform is a preset N point.

8. The method according to claim 6, characterized in that The performing down-conversion processing and down-sampling processing on the multi-channel carrier aggregation data to obtain multi-channel frequency domain baseband data includes: Performing multiple down-conversion processes and multiple down-sampling processes on the multi-channel carrier aggregation data to obtain multiple down-sampled data; The obtained multiple down-sampled data are used as multi-channel frequency domain baseband data; for each down-conversion process and each down-sampling process, the following operations are performed respectively: Determine the frequency point and the target number of shift points corresponding to the target frequency band center of the multiple frequency domain baseband data in the current down-conversion process according to the target carrier frequency required for up-conversion of the baseband signal and the preset carrier frequency of the baseband signal; the baseband signal is any one of the multiple baseband signals; the target frequency band center is the preset carrier frequency of the baseband signal; Taking the frequency point corresponding to the center of the target frequency band as a reference point, the multi-channel carrier aggregation data is overall shifted by the target shift point number to obtain down-converted data; The number of sample points is determined according to the ratio of the bandwidth of the baseband signal to the preset bandwidth, and the data other than the number of sample points at both ends of the down-converted data are discarded to obtain down-sampled data.

9. The method according to claim 6, characterized in that The method of converting the multi-channel frequency domain baseband data from the frequency domain to the time domain by a second inverse fast Fourier transform to obtain a multi-channel baseband signal comprises: For each channel of frequency domain baseband data, perform the following operations: Determining the number of sample points corresponding to the second inverse fast Fourier transform according to the ratio of the bandwidth of the baseband signal corresponding to the frequency domain baseband data to the preset bandwidth; Perform inverse fast Fourier transform on the frequency domain baseband data according to the number of sample points to obtain a baseband signal.

10. The method according to claim 6, characterized in that After obtaining the multi-path baseband signals, the method further comprises: A low-pass filter corresponding to each baseband signal is determined according to the bandwidth of each baseband signal, and the baseband signal is processed by using the low-pass filter.

11. An electronic device, characterized in that: include: Processor and memory; The memory is used to store the processor executable instructions; The processor is configured to execute the instructions to implement the method for processing a low-orbit satellite multi-channel signal according to any one of claims 1-10.

12. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by a processor of a device, the device is enabled to execute the method for processing a low-orbit satellite multi-channel signal as described in any one of claims 1 to 10.

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