Method and device for calculating carrier frequency and initial phase of MPSK signal, storage medium and electronic equipment

Abstract

The embodiment of the invention provides an MPSK signal carrier frequency and initial phase calculation method and device, a storage medium and electronic equipment, and relates to the field of digital communication, and the method comprises the steps: combining different frequencies and initial phases, and generating a plurality of local carrier sequences; carrying out calculation processing on the received MPSK signal and each sequence in the plurality of local carrier wave sequences; and confirming the carrier frequency and the initial phase of the MPSK signal based on the calculation processing result. Compared with a traditional scheme adopting a phase-locked loop, the technical scheme provided by the invention cancels feedback iterative operation among traditional algorithm data while not causing performance loss, and can be used for scenes of satellite signal transmission, remote sensing and high-speed wireless signal demodulation.

Description

Technical Field

[0001] The present application relates to the field of digital communication technology, and in particular to a method, device, storage medium and electronic device for calculating the carrier frequency and initial phase of an MPSK signal. Background Art

[0002] Due to resource limitations, communication digital signal processing has traditionally used feedback algorithms. That is, using a feedback loop, the calculation result of the previous data in the time sequence is used to calculate the current data, and the current calculation result is used to calculate the next input signal. Figure 1 A typical feedback loop is described. The algorithm uses the loop to extract the phase error of the previous data and control the loop to generate new frequency and phase.

[0003] With the development of technology, resources are no longer the main problem that plagues algorithms. Currently, there are two major advances in science and technology. One is processor technology. When the CPU's processing rate reaches its limit, new technologies such as multi-core, many-core, and GPU emerge. On the other hand, Ethernet has a rate from 1G to 100G. All kinds of data are encapsulated into network data packets and transmitted to the most efficient place for calculation. How to make more effective use of new technologies is a problem that needs to be solved in communication signal processing.

[0004] For narrowband signals, because the data rate is low and the transmission and computing requirements are limited, general CPU processors can continue to use traditional loop algorithms for processing, which can achieve the purpose of economy and convenience.

[0005] However, when the communication signal bandwidth exceeds 100MHz or even reaches several GHz, the current general computing platform is powerless, which is exactly the problem caused by the feedback loop. On the one hand, the transmission jitter of high-speed network data packets increases significantly, the relationship between the data is disturbed, 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] The embodiments of the present application provide a method, device, storage medium and electronic device for calculating the carrier frequency and initial phase of an MPSK signal to solve the problem of low signal demodulation efficiency on a general computing platform.

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

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

[0009] Combining different frequencies with initial phases to generate several local carrier sequences;

[0010] Performing calculation processing on the received MPSK signal and each of the plurality of local carrier sequences;

[0011] The carrier frequency and initial phase of the MPSK signal are confirmed based on the result of the calculation process.

[0012] In some embodiments of the present application, based on the above scheme, the step of calculating and processing the received MPSK signal and each of the plurality of local carrier sequences includes:

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

[0014] In some embodiments of the present application, based on the above scheme, the step of confirming the carrier frequency and initial phase of the MPSK signal based on the result of the calculation process includes:

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

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

[0017] In some embodiments of the present application, based on the aforementioned solution, the frequency range of the plurality of local carrier sequences matches the frequency range of the received MPSK signal.

[0018] In some embodiments of the present application, based on the aforementioned solution, 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 the present application, based on the above-mentioned solution, the array length of each carrier sequence in 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 an embodiment of the present application, there is provided a device for calculating a carrier frequency and an initial phase of an MPSK signal, comprising:

[0021] A generating unit, used for combining different frequencies with initial phases to generate a number of local carrier sequences;

[0022] a calculation unit, configured to perform calculation processing 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 result of the calculation process.

[0024] According to a third aspect of an embodiment of the present application, a computer-readable storage medium is provided, wherein the storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer executes the method according to the first aspect.

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

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

[0027] The processor is used to call the computer instructions stored in the memory so that the electronic device executes the method as described in the first aspect.

[0028] The technical solution of the present application proposes a signal demodulation method with performance comparable to that of conventional technology but without a feedback loop, which makes it possible to perform communication signal processing on general computing platforms such as GPUs.

[0029] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0031] Figure 1 A typical feedback loop schematic is shown;

[0032] Figure 2 A flow chart of a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of the present application is shown;

[0033] Figure 3 A logic diagram of a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of the present application is shown;

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

[0035] Figure 5 A schematic diagram of demodulation performance using the present method is shown;

[0036] Figure 6A block diagram of a device for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of the present application is shown;

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

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

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

[0040] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the 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 may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0042] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0043] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the objects used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those shown or described.

[0044] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Some embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0046] See also Figure 2 , shows a flow chart of a method for calculating the carrier frequency and initial phase of an MPSK signal according to an embodiment of the present application.

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

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

[0049] refer to Figure 2 , step S100, combining different frequencies and initial phases to generate several local carrier sequences.

[0050] Exemplarily, the expression of 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 represents an array in a two-dimensional carrier space, the length of each array is L, the subscript i represents its frequency, ω dl Refers to the lowest possible frequency of the input signal, ω ul represents the highest possible frequency of the input signal. The subscript j represents its phase, and π / k is the search range.

[0053] Continue to refer Figure 2 , step S200, calculating and processing the received MPSK signal (multi-level phase shift keying signal) and each of the several local carrier sequences.

[0054] Exemplarily, the expression of the received MPSK signal is:

[0055]

[0056] Among them, rcv(n) represents the MPSK signal, and the length of the MPSK signal array is L. A(n) represents the amplitude of the nth symbol, Indicates the phase of the nth symbol, which varies according to the modulation method, ω c represents the carrier frequency, θ 0 Indicates the initial phase. is the noise at time n The sampling of is Gaussian white noise, power spectral density The existence of Ince white noise does not affect the processing flow and results, and will not be included in the subsequent processing.

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

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

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

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

[0061] Exemplarily, the steps are as follows:

[0062] The point-by-point conjugate multiplication of one of several local carrier sequences and the received MPSK signal is expressed as:

[0063]

[0064] After k power,

[0065]

[0066] in is the kth power of the transmitted signal, k is half of the number of points in the outermost circle of the constellation points mapped by the transmitted signal. After the amplitude is raised to the kth power, the influence of the outer circle is more significant than that of the inner circle, so only the outer circle constellation mapping points are considered. The absolute values ​​of the in-phase component and the orthogonal component are:

[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. The sum of (5)-(6) is equal to

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

[0071] When Δω=0, 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 sum of equations (5)-(6) reaches a maximum value.

[0074] At this time i ,θ j The corresponding carrier frequency and phase of the received MPSK signal are shown in Figure 4 .

[0075] Continue to refer Figure 2 , step S300, confirming the carrier frequency and initial phase of the MPSK signal based on the result of the calculation process.

[0076] In some feasible embodiments, based on the above scheme, the step of confirming 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 summed results;

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

[0079] It can be understood that the frequency and initial phase corresponding to the largest one among all the summation results are the carrier frequency and initial phase of the received MPSK signal.

[0080] In some feasible embodiments, based on the above-mentioned solution, the frequency range of the plurality of local carrier sequences matches the frequency range of the received MPSK signal.

[0081] In some feasible embodiments, based on the above 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 above solution, the array length of each carrier sequence in the plurality of local carrier sequences is the same as the array length of the received MPSK signal.

[0084] In summary, compared with the traditional solution using a phase-locked loop, this technical solution eliminates the feedback iteration operation between traditional algorithm data without causing performance loss. This method can be used in scenarios such as satellite signal transmission, remote sensing, and high-speed wireless signal demodulation.

[0085] See also Figure 5 , Figure 5 The performance of 16APSK demodulation using this method is as follows: Figure 4 As shown, the performance of this method is not deteriorated compared with the traditional demodulation method using a carrier loop.

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

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

[0088] A generating unit 601 is used to combine different frequencies with initial phases to generate a number of local carrier sequences;

[0089] A calculation unit 602 is used to perform calculation processing on the received MPSK signal and each sequence 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 result of the calculation process.

[0091] like Figure 7 As shown, an embodiment of the present application 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, the steps of the above-mentioned method for calculating the carrier frequency and initial phase of an MPSK signal are implemented.

[0092] Since the electronic device introduced in this embodiment is a device used to implement a calculation device for the carrier frequency and initial phase of an MPSK signal in the embodiment of the present application, based on the method introduced in the embodiment of the present application, technical personnel in this field can understand the specific implementation method of the electronic device of this embodiment and its various variations. Therefore, how the electronic device implements the method in the embodiment of the present application is not introduced in detail here. As long as the equipment used by technical personnel in this field to implement the method in the embodiment of the present application is within the scope of protection of this application.

[0093] During the specific implementation process, when the computer program 711 is executed by a processor, any implementation method in the embodiments corresponding to the first aspect can be implemented.

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

[0095] It should be noted that Figure 8 The computer system 800 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present 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 according to the program stored in the read-only memory (ROM) 802 or the program loaded from the storage part 808 to the random access memory (RAM) 803, such as executing the method described in the above embodiment. In the RAM 803, various programs and data required for system operation are also stored. The CPU 801, ROM 802 and RAM 803 are connected to each other through a bus 804. An input / output (I / O) interface 805 is also connected to the bus 804.

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

[0098] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication section 809, and / or installed from a removable medium 811. When the computer program is executed by a central processing unit (CPU) 801, various functions defined in the system of the present application are executed.

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

[0100] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, functions and operations of the system, method and computer program product according to various embodiments of the present application. Wherein, each box in the flowchart or block diagram can represent a module, a program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0101] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. The names of these units do not, in some cases, constitute limitations on the units themselves.

[0102] As another aspect, the present application further provides a computer program product or a computer program, the computer program product or the computer program including computer instructions, the computer instructions being stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes a method for calculating the carrier frequency and initial phase of an MPSK signal described in the above embodiment.

[0103] As another aspect, the present application also provides a computer-readable medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above computer-readable medium carries one or more programs, and when the above one or more programs are executed by an electronic device, the electronic device implements a method for calculating the carrier frequency and initial phase of an MPSK signal described in the above embodiment.

[0104] It should be noted that, although several modules or units of the equipment for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into being embodied by multiple modules or units.

[0105] Through the description of the above implementation methods, it is easy for those skilled in the art to understand that the example implementation methods described here can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the implementation methods of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, a touch terminal, or a network device, etc.) to execute the method according to the implementation methods of the present application.

[0106] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in the present application. It should be understood that the present 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 the scope thereof. The scope of the present 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: Combining different frequencies with initial phases to generate several local carrier sequences; Performing calculation processing on the received MPSK signal and each of the plurality of local carrier sequences; The carrier frequency and initial phase of the MPSK signal are confirmed based on the result of the calculation process.

2. The method according to claim 1, characterized in that The step of calculating and processing the received MPSK signal and each of the plurality of local carrier sequences comprises: The received MPSK signal is conjugate-multiplied point by point with each of the plurality of local carrier sequences, raised to the kth power point by point, the difference between the absolute values ​​of the in-phase component and the orthogonal 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 method of confirming the carrier frequency and initial phase of the MPSK signal based on the result of the calculation process includes: Find the maximum value from the summed results; The frequency and initial phase corresponding to the maximum value are confirmed as the carrier frequency and initial phase of the MPSK signal.

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

5. The method according to any one of claims 1 to 3, characterized in that: 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.

6. The method according to any one of claims 1 to 3, characterized in that The array length of each carrier sequence in the plurality of 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: A generating unit, used for combining different frequencies with initial phases to generate a number of local carrier sequences; a calculation unit, configured to perform calculation processing 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 result of the calculation process.

8. A computer-readable storage medium, characterized in that: The storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer is enabled to execute the method according to any one of claims 1 to 6.

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

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