A method and device for calculating carrier frequency and initial phase of an MPSK signal, a storage medium and an electronic device

Abstract

Embodiments of the present application provide a method and device for calculating MPSK signal carrier frequency and initial phase, a storage medium and an electronic device, relating to the field of digital communication. The method comprises: combining different frequencies and initial phases to generate a plurality of local carrier sequences; calculating and processing the received MPSK signal and each sequence in the plurality of local carrier sequences; and confirming the carrier frequency and initial phase of the MPSK signal based on the result of the calculation and processing. Compared with the traditional phase-locked loop scheme, the technical solution of the present application cancels the feedback iteration operation between the data of the traditional algorithm without causing performance loss. The method can be used in the scenarios of satellite signal transmission, remote sensing and high-speed wireless signal demodulation.

Description

Technical Field

[0001] This application relates to the field of digital communication technology, and more specifically, to a method, apparatus, storage medium, and electronic device for calculating the carrier frequency and initial phase of an MPSK signal. Background Technology

[0002] Due to resource constraints, communication-related digital signal processing traditionally employs feedback algorithms. This involves using a feedback loop to apply the calculation result of the previous data to the calculation of the current data, and the current calculation result is then used to calculate the next input signal. Figure 1 A typical feedback loop is described. The algorithm uses the loop to extract the phase detection error from the previous data and control the loop to generate a new frequency and phase.

[0003] With the development of technology, resources are no longer the main problem hindering algorithms. Currently, there has been significant progress in two aspects of science and technology. One is processor technology. After the processing speed of CPUs reached its limit, new technologies such as multi-core, many-core, and GPUs emerged. The other is Ethernet, with speeds increasing from 1G to 100G. Various data are encapsulated into network data packets and transmitted to the most efficient places for computation. How to make better use of new technologies is a problem that communication signal processing needs to solve.

[0004] For narrowband signals, due to the low data rate and limited transmission and computation requirements, CPU processors can generally continue to use traditional loop algorithms for processing, which is economical and convenient.

[0005] However, when the bandwidth of communication signals exceeds 100MHz or even reaches several GHz, current general-purpose computing platforms are powerless, which is precisely the problem caused by feedback loops. On the one hand, the transmission jitter of high-speed network data packets increases significantly, the sequential relationship between data is interfered with, and the feedback loop cannot work; on the other hand, the feedback algorithm structure requires frequent data exchange, which leads to inefficiency in each link. Summary of the Invention

[0006] Embodiments of this application provide a method, apparatus, storage medium, and electronic device for calculating the carrier frequency and initial phase of an MPSK signal, in order to solve the problem of low efficiency in signal demodulation on a general computing platform.

[0007] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0008] According to a first aspect of the embodiments of this application, a method for calculating the carrier frequency and initial phase of an MPSK signal is provided, comprising:

[0009] By combining different frequencies with the initial phase, several local carrier sequences are generated;

[0010] The received MPSK signal is processed in conjunction with each of the several local carrier sequences.

[0011] Based on the results of the calculation, the carrier frequency and initial phase of the MPSK signal were confirmed.

[0012] In some embodiments of this application, based on the foregoing scheme, the step of performing calculations on the received MPSK signal and each of the plurality of local carrier sequences includes:

[0013] The received MPSK signal is sequentially multiplied point-by-point by each of the several local carrier sequences, raised to the power of k point-by-point, and the difference between the absolute values ​​of the in-phase component and the quadrature component is calculated point-by-point, and the cumulative sum of the differences is calculated.

[0014] In some embodiments of this application, based on the foregoing scheme, confirming the carrier frequency and initial phase of the MPSK signal based on the result of calculation processing includes:

[0015] Find the maximum value from the summation results;

[0016] The frequency and initial phase corresponding to the maximum value are identified as the carrier frequency and initial phase of the MPSK signal.

[0017] In some embodiments of this application, based on the foregoing scheme, the frequency range of the plurality of local carrier sequences matches the frequency range of the received MPSK signal.

[0018] In some embodiments of this application, based on the aforementioned scheme, the phase range of the plurality of local carrier sequences and the phase range of the received MPSK signal are both from 0 to π / k.

[0019] In some embodiments of this application, based on the foregoing scheme, the array length of each of the plurality of local carrier sequences is the same as the array length of the received MPSK signal.

[0020] According to a second aspect of the embodiments of this application, a device for calculating the carrier frequency and initial phase of an MPSK signal is provided, comprising:

[0021] The generation unit is used to combine different frequencies with the initial phase to generate several local carrier sequences;

[0022] A calculation unit is used to perform calculations on the received MPSK signal and each of the plurality of local carrier sequences;

[0023] The confirmation unit is used to confirm the carrier frequency and initial phase of the MPSK signal based on the results of the calculation process.

[0024] According to a third aspect of the embodiments of this application, a computer-readable storage medium is provided, the storage medium storing computer instructions that, when executed on a computer, cause the computer to perform the method as described in the first aspect.

[0025] According to a fourth aspect of the embodiments of this application, an electronic device is provided, including: a memory and a processor;

[0026] The memory is used to store computer instructions;

[0027] The processor is configured to invoke computer instructions stored in the memory, causing the electronic device to execute the method described in the first aspect.

[0028] The technical solution of this application proposes a signal demodulation method with performance comparable to traditional techniques, but without feedback loops. This method makes it possible to perform communication signal processing on general-purpose computing platforms such as GPUs.

[0029] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0031] Figure 1 A typical feedback loop diagram is shown.

[0032] Figure 2 A flowchart illustrating a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of this application is shown.

[0033] Figure 3 A logical schematic diagram of a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of this application is shown.

[0034] Figure 4 A schematic diagram of the carrier frequency and phase of an MPSK signal according to an embodiment of this application is shown;

[0035] Figure 5 A schematic diagram illustrating the demodulation performance using this method is shown.

[0036] Figure 6A block diagram of a calculation apparatus for MPSK signal carrier frequency and initial phase according to an embodiment of this application is shown;

[0037] Figure 7 A block diagram of an electronic device according to one embodiment of this application is shown;

[0038] Figure 8 A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown. Detailed Implementation

[0039] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0040] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0041] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0042] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of these terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described.

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0045] The following detailed description of some embodiments of this application will be provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0046] See Figure 2 The diagram shows a flowchart illustrating a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of this application.

[0047] See Figure 3 The diagram illustrates a logical schematic of a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of this application.

[0048] like Figure 2 As shown, a method for calculating the carrier frequency and initial phase of an MPSK signal is illustrated, specifically including steps S100 to S300.

[0049] refer to Figure 2 In step S100, different frequencies are combined with the initial phase to generate several local carrier sequences.

[0050] For example, the expression for the local carrier sequence is as follows:

[0051] wlocal i,j (n)=exp(j(ω i n+θ j ),n∈[1,L],i∈[ω dl ,ω ul ],j∈[0,π / k); (1)

[0052] Among them, wlocal i,j This represents an array in a two-dimensional carrier space, where each array has a length of L, and the subscript i indicates its frequency, ω. dl The lowest possible frequency of the input signal, ω. ul This indicates the highest possible frequency of the input signal. The subscript j indicates its phase, and π / k is the search range.

[0053] Continue to refer to Figure 2 In step S200, the received MPSK signal (multi-level phase shift keying signal) is processed in conjunction with each of the several local carrier sequences.

[0054] For example, the expression for the received MPSK signal is:

[0055]

[0056] Where rcv(n) represents the MPSK signal, and the MPSK signal array has a length of L. A(n) represents the amplitude of the nth symbol. ω represents the phase of the nth symbol, which varies depending on the modulation method. c θ represents the carrier frequency, and θ0 represents the initial phase. It is the noise at time n. Sampling, It is Gaussian white noise with a power spectral density. The presence of Ings white noise does not affect the processing flow and results, and will not be included in subsequent processing.

[0057] It should be noted that this scheme is used for digital signal processing, and the received MPSK signal and several local carrier sequences are all complex digital signals.

[0058] In some feasible embodiments, based on the foregoing scheme, the step of performing calculations on the received MPSK signal and each of the plurality of local carrier sequences includes:

[0059] The received MPSK signal is sequentially multiplied point-by-point by each of the several local carrier sequences, raised to the power of k point-by-point, and the difference between the absolute values ​​of the in-phase component and the quadrature component is calculated point-by-point, and the cumulative sum of the differences is calculated.

[0060] It should be noted that the correspondence between k powers and MPSK signals is half the number of points on the outermost ring of the constellation mapped by the modulation scheme. For example, BPSK (2PSK) has two points on the outermost ring, so k = 1; QPSK (4PSK) has four points on the outermost ring, so k = 2; 8PSK has eight points on the outermost ring, so k = 4; 16APSK has twelve points on the outermost ring, so k = 6; 32APSK has sixteen points on the outermost ring, so k = 8; and so on.

[0061] For example, the steps are as follows:

[0062] The pointwise conjugate multiplication of a given local carrier sequence with the received MPSK signal is expressed as:

[0063]

[0064] After k powers

[0065]

[0066] in The amplitude is raised to the power of k, where k is half the number of points on the outermost ring of the constellation mapped by the transmitted signal. After the amplitude is raised to the power of k, the influence of the outer ring is more significant than that of the inner ring. Only the outer ring constellation mapping points are considered. The absolute values ​​of the in-phase component and the quadrature component are respectively:

[0067] A k (n)abs(cos(kΔωn+kΔθ)); (5)

[0068] A k (n)abs(sin(kΔωn+kΔθ); (6)

[0069] When Δω≠0, there is no need to consider the value of Δθ, and the sum of (5)-(6) equals

[0070] A k (n)·∑ L abs(cos(kΔωn)-abs(sin(kΔωn)) k (n)·L;(7)

[0071] When Δω=0, then the sum of equations (5)-(6) equals

[0072] A k (n)·∑ L abs(cos(kΔθ)-sin(kΔθ))=A k (n)·L·abs(cos(kΔθ)-sin(kΔθ)); (8)

[0073] Therefore, when Δω=0 and Δθ=0, the summation of equations (5)-(6) has a maximum value.

[0074] At this time ω i θ j The corresponding values ​​are the carrier frequency and phase of the received MPSK signal, see [link / reference]. Figure 4 .

[0075] Continue to refer to Figure 2 Step S300: Based on the calculation results, confirm the carrier frequency and initial phase of the MPSK signal.

[0076] In some feasible embodiments, based on the foregoing scheme, the confirmation of the carrier frequency and initial phase of the MPSK signal based on the result of the calculation process includes:

[0077] Find the maximum value from the summation results;

[0078] The frequency and initial phase corresponding to the maximum value are identified as the carrier frequency and initial phase of the MPSK signal.

[0079] ​It is understandable that the frequency and initial phase corresponding to the largest summation result are the carrier frequency and initial phase of the received MPSK signal.

[0080] In some feasible embodiments, based on the foregoing scheme, the frequency range of the plurality of local carrier sequences is matched with the frequency range of the received MPSK signal.

[0081] In some feasible embodiments, based on the aforementioned scheme, the phase range of the plurality of local carrier sequences and the phase range of the received MPSK signal are both from 0 to π / k.

[0082] It should be noted that frequency resolution and phase resolution are related to demodulation performance and array length.

[0083] In some feasible embodiments, based on the foregoing scheme, the array length of each of the plurality of local carrier sequences is the same as the array length of the received MPSK signal.

[0084] In summary, compared with traditional phase-locked loop (PLL) solutions, this technical solution eliminates the feedback iterative operations between data in traditional algorithms without causing performance loss. This method can be applied to scenarios such as satellite signal transmission, remote sensing, and high-speed wireless signal demodulation.

[0085] See Figure 5 , Figure 5 To assess the performance of 16APSK demodulation using this method, such as... Figure 4 As shown, the performance of this method is not degraded compared to the traditional demodulation method using a carrier loop.

[0086] The following describes an embodiment of the apparatus described in this application, which can be used to execute a method for calculating the carrier frequency and initial phase of an MPSK signal as described in the above embodiments of this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0087] Reference Figure 6 As shown, a calculation device for the carrier frequency and initial phase of an MPSK signal according to an embodiment of this application includes:

[0088] The generation unit 601 is used to combine different frequencies with the initial phase to generate several local carrier sequences;

[0089] The calculation unit 602 is used to perform calculations on the received MPSK signal and each of the plurality of local carrier sequences;

[0090] The confirmation unit 603 is used to confirm the carrier frequency and initial phase of the MPSK signal based on the results of the calculation process.

[0091] like Figure 7As shown, this application embodiment also provides an electronic device 700, including a memory 710, a processor 720, and a computer program 711 stored in the memory 710 and executable on the processor. When the processor 720 executes the computer program 711, it implements the steps of the above-mentioned method for calculating the carrier frequency and initial phase of an MPSK signal.

[0092] Since the electronic device described in this embodiment is the device used to implement the calculation device for MPSK signal carrier frequency and initial phase in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in the embodiments of this application. Therefore, how the electronic device implements the method in the embodiments of this application will not be described in detail here. Any device used by those skilled in the art to implement the method in the embodiments of this application falls within the scope of protection of this application.

[0093] In practice, when the computer program 711 is executed by the processor, it can implement any of the embodiments corresponding to the first aspect.

[0094] Figure 8 A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown.

[0095] It should be noted that, Figure 8 The computer system 800 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0096] like Figure 8 As shown, the computer system 800 includes a Central Processing Unit (CPU) 801, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 802 or programs loaded from storage portion 808 into Random Access Memory (RAM) 803, such as performing the methods described in the above embodiments. The RAM 803 also stores various programs and data required for system operation. The CPU 801, ROM 802, and RAM 803 are interconnected via a bus 804. An Input / Output (I / O) interface 805 is also connected to the bus 804.

[0097] The following components are connected to I / O interface 805: an input section 806 including a keyboard, mouse, etc.; an output section 807 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 808 including a hard disk, etc.; and a communication section 809 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 809 performs communication processing via a network such as the Internet. A drive 810 is also connected to I / O interface 805 as needed. A removable medium 811, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 810 as needed so that computer programs read from it can be installed into storage section 808 as needed.

[0098] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 809, and / or installed from removable medium 811. When the computer program is executed by central processing unit (CPU) 801, it performs various functions defined in the system of this application.

[0099] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such transmitted data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0100] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0101] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0102] In another aspect, this application also provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the method for calculating the MPSK signal carrier frequency and initial phase described in the above embodiments.

[0103] In another aspect, this application also provides a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to implement the method for calculating the MPSK signal carrier frequency and initial phase as described in the above embodiments.

[0104] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0105] Through the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, touch terminal, or network device, etc.) to execute the method according to the embodiments of this application.

[0106] Other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. It should be understood that this application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for calculating the carrier frequency and initial phase of an MPSK signal, characterized in that, include: By combining different frequencies with the initial phase, several local carrier sequences are generated; The received MPSK signal is processed in conjunction with each of the several local carrier sequences. Based on the results of the calculation, the carrier frequency and initial phase of the MPSK signal were confirmed.

2. The method according to claim 1, characterized in that, The step of performing calculations on the received MPSK signal and each of the plurality of local carrier sequences includes: The received MPSK signal is sequentially multiplied point-by-point by each of the several local carrier sequences, raised to the power of k point-by-point, and the difference between the absolute values ​​of the in-phase component and the quadrature component is calculated point-by-point, and the cumulative sum of the differences is calculated.

3. The method according to claim 2, characterized in that, The determination of the carrier frequency and initial phase of the MPSK signal based on the calculation results includes: Find the maximum value from the summation results; The frequency and initial phase corresponding to the maximum value are identified as the carrier frequency and initial phase of the MPSK signal.

4. The method according to any one of claims 1-3, characterized in that, The frequency range of the aforementioned local carrier sequences matches the frequency range of the received MPSK signal.

5. The method according to any one of claims 1-3, characterized in that, The phase range of the aforementioned local carrier sequences and the phase range of the received MPSK signal are both from 0 to π / k.

6. The method according to any one of claims 1-3, characterized in that, The array length of each of the several local carrier sequences is the same as the array length of the received MPSK signal.

7. A device for calculating the carrier frequency and initial phase of an MPSK signal, characterized in that, include: The generation unit is used to combine different frequencies with the initial phase to generate several local carrier sequences; A calculation unit is used to perform calculations on the received MPSK signal and each of the plurality of local carrier sequences; The confirmation unit is used to confirm the carrier frequency and initial phase of the MPSK signal based on the results of the calculation process.

8. A computer-readable storage medium, characterized in that, The storage medium stores computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1-6.

9. An electronic device, characterized in that, include: Memory and processor; The memory is used to store computer instructions; The processor is configured to invoke computer instructions stored in the memory, causing the electronic device to perform the method as described in any one of claims 1-6.

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