Digital frequency conversion method, device, equipment and medium for digital intermediate frequency

Abstract

The invention provides a digital frequency conversion method and device for digital intermediate frequency, equipment and a medium. The method comprises the following steps: performing intermediate frequency filtering up-sampling on a carrier signal; determining the total table look-up length of the digital frequency converter in one frequency conversion period according to the frequency conversion precision of the digital frequency converter; decomposing the total table look-up length to obtain two small lengths; and carrying out intermediate frequency digital frequency conversion processing on the carrier signal after up-sampling based on the small length. According to the method provided by the invention, the total table look-up length is decomposed to obtain two small lengths; and on the basis of the small length, the up-sampled carrier signal is subjected to intermediate-frequency digital frequency conversion processing, so that the simplicity and the flexibility of the intermediate-frequency digital frequency conversion processing can be improved, and meanwhile, the resource consumption during implementation of the intermediate-frequency digital frequency conversion processing is reduced.

Description

Technical Field

[0001] The present application relates to the field of mobile communication technology, and in particular to a digital frequency conversion method, device, equipment, and medium for digital intermediate frequency. Background Art

[0002] In mobile communication systems, digital intermediate frequencies often need to process single / multi-carrier signals from the baseband, perform filtering and up-sampling, and then perform digital up-conversion or digital down-conversion according to the RF configuration of the product system link.

[0003] However, the single / multi-carrier signals from the baseband may have different signal formats, signal bandwidths, and sampling rates for NR and / or LTE, which will reduce the simplicity and flexibility of the intermediate frequency digital frequency conversion processing and increase the resource consumption during the implementation of the intermediate frequency digital frequency conversion processing. Summary of the invention

[0004] In order to solve one of the above-mentioned technical defects, the present application provides a digital frequency conversion method, device, equipment, and medium for digital intermediate frequency.

[0005] In a first aspect of the present application, a digital frequency conversion method for a digital intermediate frequency is provided, the method comprising:

[0006] Perform intermediate frequency filtering and up-sampling on the carrier signal;

[0007] According to the frequency conversion accuracy of the digital frequency converter, determine the total length of the table lookup of the digital frequency converter in one frequency conversion cycle;

[0008] Decompose the total length of the lookup table to obtain two small lengths;

[0009] Based on the small length, the up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0010] Optionally, according to the frequency conversion accuracy of the digital frequency converter, determining the total table lookup length of the digital frequency converter in one frequency conversion cycle includes:

[0011] Determine the total length of the digital inverter's table lookup in one frequency conversion cycle

[0012] Among them, Fs is the sampling rate after upsampling, precision is the frequency conversion accuracy of the digital frequency converter;

[0013] t is the sampling interval after upsampling.

[0014] Optionally, the total length of the table lookup is decomposed to obtain two small lengths, including:

[0015] The total length of the table lookup is decomposed by the formula tabLen=tabLen1·tabLen2 to obtain two small lengths;

[0016] Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

[0017] Optionally, based on the short length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal includes:

[0018] Determine the table value separately and Among them, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths;

[0019] according to and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0020] Optionally, determine the table lookup value and include:

[0021] Sure

[0022] Among them, f unit is the normalized frequency offset value.

[0023] Optionally, Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

[0024] Optionally, according to and Performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, including:

[0025] Determine the exponential value of the frequency shift Wherein, n is the digital domain sampling point identifier, n=0,1,2,…,tabLen-1, and tabLen is the total length of the lookup table;

[0026] By the formula y(n) = x(n)·e′ vak (n) performs intermediate frequency digital frequency conversion processing, wherein x(n) is the carrier signal obtained at sampling point n after upsampling, and y(n) is the carrier signal after intermediate frequency digital frequency conversion processing is performed at sampling point n.

[0027] In a second aspect of the present application, a digital frequency conversion device for a digital intermediate frequency is provided, the device comprising:

[0028] An up-sampling module, used for performing intermediate frequency filtering and up-sampling on the carrier signal;

[0029] A determination module, used to determine the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter;

[0030] A decomposition module is used to decompose the total length of the table lookup determined by the determination module to obtain two small lengths;

[0031] The processing module is used for performing intermediate frequency digital frequency conversion processing on the carrier signal sampled by the up-sampling module based on the small length decomposed by the decomposition module.

[0032] In a third aspect of the present application, an electronic device is provided, including:

[0033] Memory;

[0034] Processor; and

[0035] Computer programs;

[0036] The computer program is stored in the memory and is configured to be executed by the processor to implement the method as described in the first aspect above.

[0037] In a fourth aspect of the present application, a computer-readable storage medium is provided, on which a computer program is stored; the computer program is executed by a processor to implement the method described in the first aspect above.

[0038] The present application provides a digital frequency conversion method, device, equipment, and medium for digital intermediate frequency, the method comprising: performing intermediate frequency filtering and upsampling on a carrier signal; determining the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter; decomposing the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal. The method provided in the present application decomposes the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, which can improve the simplicity and flexibility of intermediate frequency digital frequency conversion processing, while reducing resource consumption when implementing intermediate frequency digital frequency conversion processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0040] Figure 1 A schematic diagram of a digital intermediate frequency processing provided in an embodiment of the present application;

[0041] Figure 2 A schematic diagram of a digital intermediate frequency 4-carrier frequency conversion provided in an embodiment of the present application;

[0042] Figure 3 A flow chart of a digital frequency conversion method for a digital intermediate frequency provided in an embodiment of the present application;

[0043] Figure 4 A schematic diagram of the structure of a digital frequency conversion device for digital intermediate frequency provided in an embodiment of the present application;

[0044] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0046] In the process of implementing this application, the inventors found that in mobile communication systems, digital intermediate frequencies often need to process single / multi-carrier signals from the baseband, perform filtering and up-sampling according to the RF configuration of the product system link, and then perform digital up-conversion or digital down-conversion. However, the single / multi-carrier signals from the baseband will have different signal formats, signal bandwidths and sampling rates for NR and / or LTE, which will reduce the simplicity and flexibility of the intermediate frequency digital frequency conversion processing and increase the resource consumption when implementing the intermediate frequency digital frequency conversion processing.

[0047] In response to the above problems, the present application provides a digital frequency conversion method, device, equipment, and medium for digital intermediate frequency, the method comprising: performing intermediate frequency filtering and upsampling on the carrier signal; determining the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter; decomposing the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal. The method provided in the present application decomposes the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, which can improve the simplicity and flexibility of intermediate frequency digital frequency conversion processing, while reducing resource consumption when implementing intermediate frequency digital frequency conversion processing.

[0048] like Figure 1As shown in the figure, during the digital intermediate frequency link processing, the digital intermediate frequency module processes the four carrier signals sent from the physical layer PHY (Physical Layer), including one carrier with a bandwidth of 100MHz and a sampling rate of 122.88Msps, and three carriers with a bandwidth of 20MHz and a sampling rate of 30.72Msps. These four carrier signals are filtered and converted by the digital intermediate frequency up-sampling module, and finally synthesized into a signal with a bandwidth of 160MHz and a sampling rate of 245.76Msps and sent out, as shown in the figure. Figure 2 shown.

[0049] from Figure 1 It can be seen from the processing logic that each carrier needs to be frequency-converted by the frequency converter, and the frequency converter implements the frequency conversion operation through the digital frequency conversion method for digital intermediate frequency provided in this embodiment.

[0050] See also Figure 3 The implementation process of the digital frequency conversion method for digital intermediate frequency provided in this embodiment is as follows:

[0051] 301, perform intermediate frequency filtering and up-sampling on the carrier signal.

[0052] For example, the single / multi-carrier signal sent from the baseband is subjected to intermediate frequency filtering and upsampling. Upsampling can upsample each carrier to Fs, where Fs is the sampling rate after upsampling. t is the sampling interval after upsampling.

[0053] 302, determining a total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter.

[0054] Step 302 determines the total length of the table lookup of the digital frequency converter in a frequency conversion cycle. tabLen is the frequency conversion operation table lookup length.

[0055] Among them, Fs is the sampling rate after upsampling, and precision is the frequency conversion accuracy of the digital frequency converter (also the table lookup accuracy).

[0056] t is the sampling interval after upsampling.

[0057] 303, decompose the total length of the table lookup to obtain two small lengths.

[0058] Step 303 will decompose the total length of the table lookup by the formula tabLen=tabLen1·tabLen2 to obtain two small lengths.

[0059] Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

[0060] That is, if the two small lengths are tabLen1 and tabLen2, then tabLen=tabLen1·tabLen2.

[0061] 304 , based on the small length, perform intermediate frequency digital frequency conversion processing on the upsampled carrier signal.

[0062] If the input data of the intermediate frequency digital frequency conversion processing is x(n), then the output data after the intermediate frequency digital frequency conversion processing is y(n) = x(n)·e 1j·2π·Δf·n·t , where Δf is the frequency shift value, t is the sampling interval, n is the digital domain sampling point identifier, n=0,1,2,…,tabLen-1, and tabLen is the total length of the lookup table.

[0063] Since the relationship between the sampling interval t and the sampling rate Fs is Therefore, the output data

[0064] In step 304, The operation is replaced by using a table lookup method. The implementation process is as follows:

[0065] If the frequency conversion accuracy of the digital inverter (also the table lookup accuracy) is precision, then the normalized frequency offset value is Total length of table lookup

[0066] Taking NR 100M as an example, if Fs = 245.76Msps, Δf = 30MHz, precision = 15KHz, then f unit =2000,tabLen=16384.

[0067] Therefore, the table storage content with a table lookup length of tabLen=16384 is:

[0068] According to the formula When performing the intermediate frequency digital domain point-by-point table lookup and frequency conversion operation, it is necessary to traverse the digital domain sampling points n = 0, 1, 2, ..., tabLen-1 and compare n with f unit The result of the multiplication is then modulo tabLen to obtain the subscript index tabLen of the variable frequency operation polling table (i.e. tabLen = mod(n·f unit ,tabLen)), and then according to the formula The tabIndex position of the calculated frequency conversion table tabVal is used to retrieve e from this position. val (n) (i.e. the exponential value of the frequency shift), i.e. e val(n) = tabVal(tabIndex). The retrieved value e val (n) Therefore, y(n) = x(n)·e vak (n).

[0069] Since the processed signal is a complex-valued signal, The frequency shift table with a calculated length of tabLen=16384 needs to be stored in advance. According to the processing of 16 bits for both the in-phase signal I (In-phase) and the quadrature signal Q (Quadrature), a memory of 64KByte is required to store the frequency shift table. In order to reduce resource consumption when implementing the intermediate frequency digital frequency conversion processing, the method provided in this embodiment does not directly perform intermediate frequency digital frequency conversion processing on the upsampled carrier signal based on the total length of the table lookup, but first decomposes the total length of the table lookup through step 303 to obtain two small lengths, and then performs intermediate frequency digital frequency conversion processing on the upsampled carrier signal based on the small length through step 304.

[0070] That is, in step 303, tabLen is decomposed into tabLen1 and tabLen2, wherein tabLen=tabLen1·tabLen2.

[0071] So, m1=0,1,2,…,tabLen1-1, m2=0,1,2,…,tabLen2-1.

[0072] Through the above decomposition, the table storage content with a lookup length of tabLen=16384 can be split into two frequency conversion small tables. and Can be taken from two small tables and

[0073] If tabLen1=512, tabLen2=32, and the I and Q signals are processed as 16 bits, it can be calculated that the memory size required to store the two small tables is 2.125KByte. Compared with the resources occupied by the large table storage, the memory size is reduced by nearly 30 times.

[0074] When performing frequency conversion based on two frequency conversion tables, it is necessary to traverse m1=0,1,2,…,tabLen1-1 and take Value Then traverse m2=0,1,2,…,tabLen2-1 and take Value Bundle and Multiply again to get e′ val(n), that is: e′ val (n)= At this time, y(n) = x(n)·e′ val (n).

[0075] y(n)=x(n)·e val (n) and y(n) = x(n)·e′ val (n) The signal after frequency shifting has the same frequency shift behavior.

[0076] Based on the above analysis, when step 304 is specifically executed, the table lookup values ​​are determined respectively. and according to and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0077] Among them, the table lookup value is the index value of the frequency shift, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths.

[0078] Among them, in determining the table value and When

[0079] Among them, f init is the normalized frequency offset value. Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

[0080] In accordance with and When performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, the frequency shift index value is first determined. Then, through the formula y(n) = x(n)·e′ val (n) Perform intermediate frequency digital frequency conversion processing.

[0081] Where n is the digital domain sampling point identifier, n = 0, 1, 2, ..., tabLen-1, and tabLen is the total length of the lookup table. x(n) is the carrier signal obtained at sampling point n after upsampling, that is, the input of the intermediate frequency digital frequency conversion processing, and y(n) is the carrier signal after the intermediate frequency digital frequency conversion processing at sampling point n, that is, the output of the intermediate frequency digital frequency conversion processing.

[0082] The digital frequency conversion method for digital intermediate frequency provided in this embodiment updates one frequency conversion lookup table to two frequency conversion lookup tables by transforming the frequency conversion formula, thereby greatly reducing the hardware resources required for storing the frequency conversion lookup table.

[0083] The digital frequency conversion method for digital intermediate frequency provided in this embodiment is executed when up-conversion or down-conversion operation is required to process single / multi-carrier scenarios in a mobile communication system. The digital frequency conversion method for digital intermediate frequency provided in this embodiment does not rely on the intermediate frequency digital domain up-sampling module or down-sampling module. The digital frequency conversion method for digital intermediate frequency provided in this embodiment can improve the simplicity and flexibility of digital intermediate frequency module processing on the one hand, and reduce resource consumption when implementing the digital intermediate frequency converter on the other hand.

[0084] For example, the digital frequency conversion method for digital intermediate frequency provided in this embodiment is for single / multi-carrier signals sent by baseband, and first performs intermediate frequency filtering and upsampling, and then performs intermediate frequency digital frequency conversion processing on each carrier. The intermediate frequency filtering and upsampling upsamples each carrier to Fs, and combines the digital frequency converter's frequency conversion accuracy to calculate the total length of the digital frequency converter's table lookup in one frequency conversion cycle.

[0085] In 5G broadband wireless mobile communications, it is necessary to process signals with large bandwidth and high sampling rate. Therefore, when using FPGA or ASIC hardware to implement digital frequency conversion operations, the total table lookup length tabLen will be very large, which will lead to a large memory resource occupation on the one hand, and on the other hand, the hardware table lookup polling address operation will be very time-consuming. The method provided in this embodiment decomposes the total table lookup length tabLen in step 303 to obtain two small lengths tabLen1 and tabLen2, that is, tabLen=tabLen1·tabLen2. This not only greatly reduces the memory resource occupation of the frequency conversion table lookup, but also saves the time for the hardware table lookup polling address operation, thereby reducing the energy consumption of the intermediate frequency hardware implementation.

[0086] The present application provides a digital frequency conversion method, device, equipment, and medium for digital intermediate frequency, the method comprising: performing intermediate frequency filtering and upsampling on a carrier signal; determining the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter; decomposing the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal. The method provided in the present application decomposes the total table lookup length to obtain two small lengths; based on the small length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, which can improve the simplicity and flexibility of intermediate frequency digital frequency conversion processing, while reducing resource consumption when implementing intermediate frequency digital frequency conversion processing.

[0087] Based on the same inventive concept of the digital frequency conversion method for digital intermediate frequency, this embodiment provides a digital frequency conversion device for digital intermediate frequency, see Figure 4 , the device comprises:

[0088] The up-sampling module 401 is used to perform intermediate frequency filtering and up-sampling on the carrier signal.

[0089] The determination module 402 is used to determine the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter.

[0090] The decomposition module 403 is used to decompose the total table lookup length determined by the determination module 402 to obtain two small lengths.

[0091] The processing module 404 is used to perform intermediate frequency digital frequency conversion processing on the carrier signal sampled by the up-sampling module 401 based on the small length decomposed by the decomposition module 403.

[0092] The determination module 402 is used to determine the total length of the table lookup of the digital frequency converter in a frequency conversion cycle.

[0093] Among them, Fs is the sampling rate after upsampling, and precision is the frequency conversion accuracy of the digital converter.

[0094] t is the sampling interval after upsampling.

[0095] The decomposition module 403 is used to decompose the total length of the table lookup by using the formula tabLen=tabLen1·tabLen2 to obtain two small lengths.

[0096] Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

[0097] The processing module 404 is used to determine the table lookup values and Among them, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths. and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0098] Among them, determine the table value respectively and include:

[0099] Sure

[0100] Among them, f unit is the normalized frequency offset value.

[0101] in, Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

[0102] Among them, according to and Performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, including:

[0103] Determine the exponential value of the frequency shift Wherein, n is the digital domain sampling point identifier, n=0, 1, 2, ..., tabLen-1, and tabLen is the total length of the lookup table.

[0104] By the formula y(n) = x(n)·e′ val (n) performs intermediate frequency digital frequency conversion processing, wherein x(n) is the carrier signal obtained at sampling point n after upsampling, and y(n) is the carrier signal after intermediate frequency digital frequency conversion processing is performed at sampling point n.

[0105] The device provided in this embodiment decomposes the total length of the lookup table to obtain two small lengths; based on the small lengths, the intermediate frequency digital frequency conversion processing is performed on the upsampled carrier signal, which can improve the simplicity and flexibility of the intermediate frequency digital frequency conversion processing, while reducing the resource consumption when implementing the intermediate frequency digital frequency conversion processing.

[0106] Based on the same inventive concept of a digital frequency conversion method for a digital intermediate frequency, this embodiment provides an electronic device, such as Figure 5 As shown, it includes: a memory 501, a processor 502, and a computer program.

[0107] The computer program is stored in the memory 501 and is configured to be executed by the processor 502 to implement the above-mentioned digital frequency conversion method for digital intermediate frequency.

[0108] Specifically,

[0109] Perform intermediate frequency filtering and up-sampling on the carrier signal.

[0110] According to the frequency conversion accuracy of the digital frequency converter, the total table lookup length of the digital frequency converter in one frequency conversion cycle is determined.

[0111] Decompose the total length of the lookup table into two small lengths.

[0112] Based on the small length, the up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0113] Optionally, according to the frequency conversion accuracy of the digital frequency converter, determining the total table lookup length of the digital frequency converter in one frequency conversion cycle includes:

[0114] Determine the total length of the digital inverter's table lookup in one frequency conversion cycle

[0115] Among them, Fs is the sampling rate after upsampling, and precision is the frequency conversion accuracy of the digital converter.

[0116] t is the sampling interval after upsampling.

[0117] Optionally, the total length of the table lookup is decomposed to obtain two small lengths, including:

[0118] The total length of the table lookup is decomposed by the formula tabLen=tabLen1·tabLen2 to obtain two small lengths.

[0119] Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

[0120] Optionally, based on the short length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal includes:

[0121] Determine the table value separately and Among them, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths.

[0122] according to and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0123] Optionally, determine the table lookup value and include:

[0124] Sure

[0125] Among them, f unit is the normalized frequency offset value.

[0126] Optionally, Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

[0127] Optionally, according to and Performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, including:

[0128] Determine the exponential value of the frequency shift Wherein, n is the digital domain sampling point identifier, n=0, 1, 2, ..., tabLen-1, and tabLen is the total length of the lookup table.

[0129] By the formula y(n) = x(n)·e′ val (n) performs intermediate frequency digital frequency conversion processing, wherein x(n) is the carrier signal obtained at sampling point n after upsampling, and y(n) is the carrier signal after intermediate frequency digital frequency conversion processing is performed at sampling point n.

[0130] The electronic device provided in this embodiment has a computer program executed by a processor to decompose the total length of the table lookup to obtain two small lengths; based on the small lengths, the intermediate frequency digital frequency conversion processing is performed on the upsampled carrier signal, which can improve the simplicity and flexibility of the intermediate frequency digital frequency conversion processing, while reducing the resource consumption when implementing the intermediate frequency digital frequency conversion processing.

[0131] Based on the same inventive concept of the digital frequency conversion method for a digital intermediate frequency, this embodiment provides a computer-readable storage medium, and a computer program is stored thereon. The computer program is executed by a processor to implement the digital frequency conversion method for a digital intermediate frequency.

[0132] Specifically,

[0133] Perform intermediate frequency filtering and up-sampling on the carrier signal.

[0134] According to the frequency conversion accuracy of the digital frequency converter, the total table lookup length of the digital frequency converter in one frequency conversion cycle is determined.

[0135] Decompose the total length of the lookup table into two small lengths.

[0136] Based on the small length, the up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0137] Optionally, according to the frequency conversion accuracy of the digital frequency converter, determining the total table lookup length of the digital frequency converter in one frequency conversion cycle includes:

[0138] Determine the total length of the digital inverter's table lookup in one frequency conversion cycle

[0139] Among them, Fs is the sampling rate after upsampling, and precision is the frequency conversion accuracy of the digital converter.

[0140] t is the sampling interval after upsampling.

[0141] Optionally, the total length of the table lookup is decomposed to obtain two small lengths, including:

[0142] The total length of the table lookup is decomposed by the formula tabLen=tabLen1·tabLen2 to obtain two small lengths.

[0143] Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

[0144] Optionally, based on the short length, performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal includes:

[0145] Determine the table value separately and Among them, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths.

[0146] according to and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

[0147] Optionally, determine the table lookup value and include:

[0148] Sure

[0149] Among them, f unit is the normalized frequency offset value.

[0150] Optionally, Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

[0151] Optionally, according to and Performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, including:

[0152] Determine the exponential value of the frequency shift Wherein, n is the digital domain sampling point identifier, n=0, 1, 2, ..., tabLen-1, and tabLen is the total length of the lookup table.

[0153] By the formula y(n) = x(n)·e′ val (n) performs intermediate frequency digital frequency conversion processing, wherein x(n) is the carrier signal obtained at sampling point n after upsampling, and y(n) is the carrier signal after intermediate frequency digital frequency conversion processing is performed at sampling point n.

[0154] The computer-readable storage medium provided in this embodiment has a computer program thereon which is executed by a processor to decompose the total length of the table lookup to obtain two small lengths; based on the small lengths, the intermediate frequency digital frequency conversion processing is performed on the upsampled carrier signal, which can improve the simplicity and flexibility of the intermediate frequency digital frequency conversion processing, while reducing the resource consumption when implementing the intermediate frequency digital frequency conversion processing.

[0155] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0156] 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 embodiments of 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 generate 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.

[0157] 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.

[0158] 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. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0159] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0160] 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. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A digital frequency conversion method for digital intermediate frequency, characterized in that: The method comprises: Perform intermediate frequency filtering and up-sampling on the carrier signal; According to the frequency conversion accuracy of the digital frequency converter, determine the total length of the table lookup of the digital frequency converter in one frequency conversion cycle; Decompose the total length of the lookup table to obtain two small lengths; Based on the small length, the up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

2. The method according to claim 1, characterized in that: The method of determining the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter comprises: Determine the total length of the digital inverter's table lookup in one frequency conversion cycle Among them, Fs is the sampling rate after upsampling, precision is the frequency conversion accuracy of the digital frequency converter; t is the sampling interval after upsampling.

3. The method according to claim 1, characterized in that The total length of the table lookup is decomposed to obtain two small lengths, including: The total length of the table lookup is decomposed by the formula tabLen=tabLen1·tabLen2 to obtain two small lengths; Among them, tabLen is the total length of the lookup table, and tabLen1 and tabLen2 are two small lengths.

4. The method according to claim 1, characterized in that: The method of performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal based on the small length includes: Determine the table value separately and Among them, m1 and m2 are table lookup parameters, m1 = 0, 1, 2, ..., tabLen1-1, m2 = 0, 1, 2, ..., tabLen2-1, tabLen1 and tabLen2 are two small lengths; according to and The up-sampled carrier signal is subjected to intermediate frequency digital frequency conversion processing.

5. The method according to claim 4, characterized in that The table lookup values ​​are determined respectively and include: Sure Among them, f unit is the normalized frequency offset value.

6. The method according to claim 5, characterized in that Said Among them, Δf is the frequency shift value, and precision is the frequency conversion accuracy of the digital inverter.

7. The method according to claim 4, characterized in that The basis and Performing intermediate frequency digital frequency conversion processing on the upsampled carrier signal, including: Determine the exponential value of the frequency shift Wherein, n is the digital domain sampling point identifier, n=0,1,2,…,tabLen-1, and tabLen is the total length of the lookup table; By the formula y(n) = x(n)·e′ val (n) performs intermediate frequency digital frequency conversion processing, wherein x(n) is the carrier signal obtained at sampling point n after upsampling, and y(n) is the carrier signal after intermediate frequency digital frequency conversion processing is performed at sampling point n.

8. A digital frequency conversion device for digital intermediate frequency, characterized in that: The device comprises: An up-sampling module, used for performing intermediate frequency filtering and up-sampling on the carrier signal; A determination module, used to determine the total table lookup length of the digital frequency converter in a frequency conversion cycle according to the frequency conversion accuracy of the digital frequency converter; A decomposition module, used for decomposing the total length of the table lookup determined by the determination module to obtain two small lengths; The processing module is used to perform intermediate frequency digital frequency conversion processing on the carrier signal sampled by the up-sampling module based on the small length decomposed by the decomposition module.

9. An electronic device, characterized in that: include: Memory; processor; as well as Computer programs; The computer program is stored in the memory and is configured to be executed by the processor to implement the method according to any one of claims 1 to 7.

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

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