A coarse frequency offset estimation method, device, computing device, storage medium, program product and chip for wireless communication

Abstract

A method, apparatus, computing device, storage medium, program product and chip for rough frequency offset estimation for wireless communication are provided. The method for rough frequency offset estimation for wireless communication comprises obtaining an observation value containing frequency offset information based on a received primary synchronization signal, wherein the observation value comprises an I-path observation value and a Q-path observation value; calculating a division term based on the I-path observation value and the Q-path observation value to obtain a division result, and performing an inverse tangent function on the division result to obtain a frequency offset estimation value. According to an exemplary embodiment, the accuracy of frequency offset estimation can be improved while reducing the resource consumption of a computing device.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a coarse frequency offset estimation method, apparatus, computing device, storage medium, program product and chip for wireless communication. Background Art

[0002] In communication technology, timing synchronization is the first step for communication equipment to achieve access. Due to the influence of the channel, the frequency deviation of the mixer, and the Doppler effect caused by the relative movement of the communication equipment and the communication end, the synchronization signal obtained by the communication equipment in the baseband contains a fractional frequency deviation. The inter-subcarrier interference caused by the frequency deviation will cause distortion to the synchronization signal and reduce the performance of frequency domain processing in the synchronization link.

[0003] In the related art, an observation containing frequency offset information is obtained through autocorrelation operation, thereby obtaining a frequency offset estimation result. In some scenarios, the synchronization signal has no adjacent repeated signals within the required time, and it is difficult to obtain an observation containing frequency offset information using the autocorrelation function. In addition, the frequency offset estimation result obtained by the observation in the related art has low accuracy.

[0004] It should be noted that the statements herein merely provide background information related to the present disclosure and do not necessarily constitute prior art. Summary of the invention

[0005] In view of the above problems, a method, apparatus, computing device, storage medium, program product and chip for coarse frequency offset estimation for wireless communication are provided to overcome the above problems or at least partially solve the above problems.

[0006] In a first aspect, a coarse frequency offset estimation method for wireless communication is provided, comprising:

[0007] Based on the received primary synchronization signal, an observation value including frequency deviation information is obtained, wherein the observation value includes an I-path observation value and a Q-path observation value; a division term is calculated based on the I-path observation value and the Q-path observation value to obtain a division result, wherein a dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and a divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value; an inverse tangent function is calculated for the division result to obtain a frequency deviation estimate; wherein the method further includes at least one of the following:

[0008] i) in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression including a term including the integer part and a term including the decimal part through Taylor series expansion, and the term including the integer part is obtained by looking up a first lookup table;

[0009] ii) In the process of obtaining the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression containing a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term containing the high-order part is obtained by looking up a second lookup table.

[0010] In a second aspect, a Doppler frequency offset estimation device for a satellite communication system is provided, comprising: a first unit, configured to obtain an observation value containing frequency offset information based on a received primary synchronization signal, wherein the observation value comprises an I-path observation value and a Q-path observation value; a second unit, configured to calculate a division term based on the I-path observation value and the Q-path observation value to obtain a division result, wherein the dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and the divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value; a third unit, configured to calculate an inverse tangent function for the division result to obtain a frequency offset estimation value; wherein the device further comprises at least one of the following:

[0011] i) in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression including a term including the integer part and a term including the decimal part through Taylor series expansion, and the term including the integer part is obtained by looking up a first lookup table;

[0012] ii) In the process of obtaining the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression containing a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term containing the high-order part is obtained by looking up a second lookup table.

[0013] According to a third aspect, a computing device is provided, comprising: at least one processor; and at least one memory storing instructions, wherein when the instructions are executed individually or collectively by the at least one processor, the computing device executes the method described in the first aspect.

[0014] In a fourth aspect, a computer storage medium is provided on which instructions are stored, characterized in that when the instructions are executed individually or collectively by at least one processor of a computing device, the computing device executes the method described in the first aspect above.

[0015] In a fifth aspect, a computer program product is provided, comprising instructions, which, when executed individually or collectively by at least one processor of a computing device, cause the computing device to execute the method described in the first aspect above.

[0016] In a sixth aspect, a chip is provided, wherein the chip comprises a circuit system, and the circuit system is configured to execute the method described in the first aspect.

[0017] At least one of the above technical solutions adopted by the exemplary embodiment can achieve the following beneficial effects:

[0018] The exemplary embodiment of the present disclosure converts the observation value containing the coarse frequency offset information into the division operation and the inverse trigonometric function operation to obtain the coarse frequency offset information, converts the division operation into the integer part operation and the decimal part operation, and divides the inverse trigonometric function operation into the high-order part operation and the low-order part operation, and finally obtains the coarse frequency offset value, thereby improving the operation speed and the accuracy of the coarse frequency offset estimation value.

[0019] The above description is only an overview of the technical solution of the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific implementation methods of the present disclosure are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of some embodiments of the present disclosure in the accompanying drawings, in which:

[0021] Figure 1 1 is a flow chart of a method for estimating a coarse frequency offset in an embodiment of the present disclosure;

[0022] Figure 2 A schematic diagram of coarse frequency offset estimation in an embodiment of the present disclosure;

[0023] Figure 3 Schematic diagram of a coarse frequency offset estimation operation method in an embodiment of the present disclosure;

[0024] Figure 4 Schematic diagram of a coarse frequency offset estimation device in an embodiment of the present disclosure;

[0025] Figure 5 A comparison diagram of the coarse frequency offset estimation accuracy in the embodiment of the present disclosure;

[0026] Figure 6 This is a simulation result diagram of coarse frequency offset estimation in an embodiment of the present disclosure;

[0027] Figure 7 It is a schematic diagram of the structure of a computing device in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0028] The principle of the present disclosure will now be described with reference to some embodiments. It should be understood that the description of these embodiments is only for illustrative purposes, and helps those skilled in the art to understand and implement the present disclosure, without any limitation to the scope of the present disclosure. The disclosure described herein can be implemented in a manner different from that described below.

[0029] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0030] References in this disclosure to "one embodiment," "an embodiment," "an exemplary embodiment," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an exemplary embodiment, whether or not explicitly described, those skilled in the art will recognize that such feature, structure, or characteristic affects incorporation into other embodiments.

[0031] It should be understood that although the terms "first" and "second" etc. may be used to describe various elements herein, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The term "and / or" as used herein includes any and all combinations of one or more of the listed terms.

[0032] The terms used herein are only for describing specific embodiments, rather than for limiting exemplary embodiments. The singular forms "one", "an", and "the" used herein also include plural forms, unless the context clearly indicates otherwise. "A group of elements" or "element set" used herein is intended to include one or more elements. It should also be understood that the terms "include", "comprise", "have", "have", "include" and / or "include", when used herein, specify the presence of the features, elements and / or parts, etc., but do not exclude the presence or addition of one or more other features, elements, parts and / or combinations thereof.

[0033] As used in this disclosure, the term "circuitry" may refer to one or more or all of the following:

[0034] (a) Hardware circuit implementation only (e.g., implementation only in analog and / or digital circuits)

[0035] (b) a combination of hardware circuitry and software, such as (where applicable):

[0036] (i) a combination of analog and / or digital hardware circuitry and software / firmware; and

[0037] (ii) any part of a hardware processor (including a digital signal processor) with software, software and memory that work together to enable a device such as a mobile phone or server to perform various functions, and

[0038] (c) A hardware circuit and / or processor, such as a microprocessor or portion of a microprocessor, that requires software (eg, firmware) to operate, but where software is not required for operation, the software may not be present.

[0039] This definition of circuitry applies to all uses of this term in this disclosure, including in any claims. As another example, as used in this disclosure, the term circuitry also includes an implementation of merely a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also includes, for example, if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing network device.

[0040] As used herein, the term "communication network" refers to a network that complies with any appropriate communication standard, such as Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IOT), New Radio (NR), Non-terrestrial Network (NTN), etc. In addition, the communication between the terminal equipment and the network equipment in the communication network can be performed according to any appropriate generation of communication protocols, including but not limited to the first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), future sixth generation (6G) communication protocols, and / or any other protocols currently known or to be developed in the future. The embodiments of the present disclosure can be applied in communication systems. In view of the rapid development in communication, there will certainly be future types of communication technologies and systems, and the present disclosure can be implemented with these technologies and systems. It should not be considered that the scope of the present disclosure is limited to the aforementioned system.

[0041] The term "satellite network equipment" used in this article refers to a node set on a satellite in a communication network. The terminal device accesses the network through this node and receives services from it. Depending on the terminology and technology applied, the satellite network equipment may refer to a base station (BS) or access point (AP) as a satellite payload, such as a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a NR NB (also known as a gNB), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), and a relay node. An example of a relay node may be an integrated access and backhaul (IAB) node. The distributed unit (DU) part of the IAB node can perform the functions of a "satellite network equipment" and can therefore operate as a network device. In the following description, the terms "satellite network equipment", "BS" and "node" may be used interchangeably.

[0042] The term "terminal device" refers to any terminal device capable of wireless communication. As an example and not a limitation, a terminal device may also be referred to as a communication device, a user equipment (UE), a user station (SS), a portable user station, a mobile station (MS), or an access terminal (AT). The terminal device may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet computer, a wearable terminal device, a personal digital assistant (PDA), a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback device, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a notebook embedded device (LEE), a laptop mounted device (LME), a USB dongle, a smart device, a wireless user equipment (CPE), an Internet of Things (IoT) device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, medical equipment and applications (e.g., remote surgery), industrial equipment and applications (e.g., robots and / or other wireless devices operating in the context of an industrial and / or automated processing chain), consumer electronic devices, relay nodes, devices operating on commercial and / or industrial wireless networks, etc. The mobile terminal (MT) part of the IAB node can perform the functions of a "terminal device" and can therefore operate as a terminal device. In the following description, the terms "terminal device", "communication device", "terminal", "computing device", "user equipment" and "UE" can be used interchangeably.

[0043] Although the functions described herein may be performed in fixed and / or wireless network nodes in various exemplary embodiments, in other exemplary embodiments, the functions may be implemented in a user equipment device (such as a cellular phone, or a tablet computer, or a laptop computer, or a desktop computer, or a mobile Internet of Things device, or a fixed Internet of Things device). For example, the user equipment device may appropriately have the corresponding capabilities described in relation to fixed and / or wireless network nodes. The user equipment device may be a user device and / or a control device, such as a chipset or a processor, which is configured to control the user device when the user device is installed therein. Examples of these functions include boot server functions and / or home user servers, which may be implemented in a user equipment device by providing the user equipment device with software configured to cause the user equipment device to execute from the perspective of these functions / nodes.

[0044] The technical terms involved in this disclosure are as follows:

[0045] PSS, (Primary Synchronization Signal) primary synchronization signal;

[0046] In an exemplary embodiment, a coarse frequency offset estimation method is designed to address the current situation of low accuracy of coarse frequency offset estimation. This method optimizes the coarse frequency offset estimation operation through Taylor series expansion, thereby improving the hardware operation speed. At the same time, it optimizes the Taylor table lookup method, thereby improving the estimation accuracy of the coarse frequency offset.

[0047] The technical solutions provided by various embodiments of the present disclosure are described in detail below in conjunction with the accompanying drawings.

[0048] The disclosed embodiments provide a method, apparatus, computing device, storage medium, program product, and chip for coarse frequency offset estimation for wireless communication. Figure 1 As shown, a schematic flow chart of a coarse frequency offset estimation method 100 in an embodiment of the present disclosure is provided. The coarse frequency offset estimation method 100 at least includes the following steps S110 to S130:

[0049] Step S110: obtaining observation values ​​including frequency offset information based on the received primary synchronization signal, wherein the observation values ​​include I-path observation values ​​and Q-path observation values.

[0050] like Figure 2As shown in FIG. 1 , the acquisition of the coarse frequency offset estimation includes the receiver using the primary synchronization signal (PSS) captured in the time domain to obtain the observed quantity. The observed quantity includes the fractional frequency offset. The fractional frequency offset required for compensation is extracted through a nonlinear function. The observed quantity is usually obtained by correlation operation, and the correlation operation can be directly implemented by multiplication and addition operation. However, the nonlinear function required to extract the fractional frequency offset cannot be directly completed by multiplication and addition operation, such as division and inverse tangent function. In order to facilitate hardware implementation, the coarse frequency offset estimation method needs to fully consider the performance and feasibility of the operation itself.

[0051] When obtaining the coarse frequency deviation, first determine the constant amplitude sequence information containing the frequency deviation information based on the time domain master synchronization signal PSS timing signal of the receiving end and the local PSS timing signal corresponding to the time domain PSS timing signal. That is, the time domain PSS timing signal of the receiving end is conjugate-point-multiplied with the local PSS timing signal corresponding to the time domain PSS timing signal to obtain the constant amplitude sequence information containing the frequency deviation information. Obtained by the following formula:

[0052]

[0053]

[0054] in is the conjugate multiplication result of the received PSS sequence and the local PSS sequence, that is, a constant amplitude sequence. To receive the PSS sequence, is the local PSS sequence, n is the sampling point number in the sequence, N is the length of the PSS sequence, "·" represents complex multiplication, "*" represents taking the complex conjugate, and R represents the product of the amplitude of the accepted PSS sequence and the local PSS sequence. represents frequency deviation, and j is an imaginary unit.

[0055] Secondly, a delayed correlation operation is performed on the constant amplitude sequence information containing the frequency offset information to obtain an observation value C containing the fractional frequency offset information. In an example, the observation value C can be obtained by the following formula:

[0056]

[0057] Through further calculation, the relevant operation links can be combined and expressed as:

[0058]

[0059] Where N is the length of the PSS signal, C is the correlation operation result (observation value), To receive the PSS sequence, is the local PSS sequence, n is the sampling point number in the sequence, N is the PSS sequence length, “·” represents complex multiplication operation, and “*” represents taking complex conjugate.

[0060] Finally, the complex phase angle of the observation value C can be obtained through calculation, and then the frequency offset estimate (coarse frequency offset) can be obtained. The normalized frequency offset estimate can be obtained by the following formula: :

[0061]

[0062] Where arctan is the inverse tangent function, image and real correspond to the Q-path observation value and I-path observation value of the observation value C. In some scenarios, the normalized frequency offset estimate can also be obtained by the following formula: :

[0063]

[0064] Where arctan is the inverse tangent function, image and real correspond to the Q-path observation value and I-path observation value of the observation value C.

[0065] It should be noted that the function based on which the frequency offset estimation value is obtained is determined by the quadrant where the frequency offset value is located, which will be described in detail later.

[0066] Step S120, calculating a division term based on the I-path observation value and the Q-path observation value to obtain a division result, wherein the dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and the divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value.

[0067] Based on step S110, in order to obtain the formula ,or The frequency offset estimate in ( contains decimals, so it is also called small multiple frequency deviation), and is easy to implement in hardware. For example, the expression function Breaking down into division And the inverse tangent function arctan(y), where the division can be further decomposed into a 1 / x operation and a multiplication operation.

[0068] In one example, in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression containing a term of the integer part and a term of the decimal part through Taylor series expansion, and the term containing the integer part is obtained by looking up a first lookup table.

[0069] For the operation of 1 / x, divide x into the integer part x0 and the decimal part x1, and perform a first-order Taylor expansion on 1 / x:

[0070]

[0071]

[0072] Among them, the function containing x0 obtains the operation result by looking up Taylor expansion table 1 (the first lookup table). The form of Taylor expansion table 1 is: The value range of All corresponding values ​​of the function are stored in the table. The table lookup method is to As the input address, find the corresponding function value.

[0073] In some embodiments, considering that when x is far from x0, the approximation error will increase, it is necessary to adjust the table lookup position according to the size of the decimal part. The reciprocal of the divisor is expressed by Taylor series expansion as:

[0074]

[0075] in, is the divisor, is the integer part, is the decimal part, including The terms of are obtained by looking up the Taylor expansion table 1 mentioned above.

[0076] Step S130, calculating an inverse tangent function on the division result to obtain a frequency deviation estimation value. In one example, in the process of calculating the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression including a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term including the high-order part is obtained by searching the second lookup table.

[0077] In order to obtain the calculation result of the inverse tangent function arctan(y), the inverse tangent function arctan(y) is expanded according to the first-order Taylor expansion as follows:

[0078]

[0079]

[0080]

[0081] In order to improve the computing efficiency of the hardware, the result of the operation is decomposed into high and low bits, where y0 is the high L bits of y. Among them, L is set according to the preset accuracy requirements. The items containing y0 are obtained by looking up Taylor expansion table 2 (the second lookup table). The form of Taylor expansion table 2 is as follows: The value range of All corresponding values ​​of the function are stored in the table. The table lookup method is to As the input address, find the corresponding function value. Let M be the maximum value of the low bit y1, and adjust the table lookup position according to the following rules:

[0082]

[0083] In one example, is the division result, is the high portion, is the low part, M is the low The maximum value of The terms of are obtained by looking up the Taylor expansion table 2 mentioned above.

[0084] It can be understood that the present disclosure decomposes the expression function containing the frequency deviation value into division and arctan(y), and further decomposes the division into 1 / x operation and multiplication operation, and divides the division result into high-order and low-order parts. The number of input bits for table lookup is reduced, and the calculation accuracy of the present disclosure is improved within the same level of table lookup range, and it can be applied to computing devices under different hardware computing power conditions.

[0085] In some embodiments, the method further includes: before calculating the division term based on the I-path observation value and the Q-path observation value, selecting one of the I-path observation value and the Q-path observation value as the dividend, and selecting the other of the I-path observation value and the Q-path observation value as the divisor according to the size relationship between the I-path observation value and the Q-path observation value; and after calculating the inverse tangent function of the division result to obtain the frequency offset estimate, adjusting the frequency offset estimate according to the size relationship between the I-path observation value and the Q-path observation value so that the adjusted frequency offset estimate falls within the range of [0,π / 4].

[0086] like Figure 3 As shown, when obtaining the frequency offset estimation value, in order to obtain better operation efficiency, the output range of the arc tangent is limited to (0, π / 4). According to the following four quadrants and corresponding angle table, the I-channel observation value and the Q-channel observation value are judged, and the divisor and dividend are adjusted and the output is restored, thereby reducing the complexity of the table lookup.

[0087] Four quadrants and corresponding angles table

[0088]

[0089] It can be understood that by comparing the magnitude relationship between the I-path observation value and the Q-path observation value, the dividend and divisor in the division term can be confirmed, and then the output range of the arc tangent can be limited to (0, π / 4), which can reduce the complexity of the table lookup and improve the operation efficiency.

[0090] In some instances, the method further includes: before calculating the division term based on the I-path observation value and the Q-path observation value, binary shifting the I-path observation value and the Q-path observation value so that the first '1' bit of the integer part of the divisor from high to low is shifted to the highest bit of the integer part.

[0091] Since the numerical values ​​of the I and Q paths of the observation value C obtained by the correlation operation cannot be determined, there is a risk of exceeding the range when looking up the table. Therefore, numerical scaling can be performed in the division operation. Adjust the divisor through binary shift: find the first '1' bit from high to low in the divisor (after taking the absolute value), and then perform a binary shift on the dividend so that the first '1' bit is shifted to the highest bit of the integer part and record the number of bits shifted. Perform a binary shift on the dividend by the same number of bits.

[0092] Here, the method of obtaining the first '1' bit is illustrated as follows: suppose the binary sequence to be searched is A, and the reverse order of A is recorded as A inv , and then to A inv The inverse is recorded as ~A inv , then A inv and (~A inv +1) and a bitwise AND operation is performed, which will inevitably result in a one-hot sequence, where the sum of the serial number of the only '1' bit and the serial number of the first '1' bit of A is the total bit width + 1, and the serial number of the first '1' bit of A can be obtained.

[0093] It can be seen that before calculating the division term, data scaling based on the method of finding the first '1' bit is used to further optimize the table lookup input range and reduce the table lookup complexity, thereby saving storage resources and improving operation efficiency.

[0094] In one example, reference Figure 3 , the coarse frequency offset estimation method comprises the following steps:

[0095] Step 1: The computing device obtains the primary synchronization signal PSS and confirms the type of the primary synchronization signal PSS.

[0096] Step 2: The computing device performs conjugate point multiplication on the received PSS signal and the corresponding local signal to obtain a constant amplitude sequence.

[0097] Step 3: Perform a delayed correlation operation on the constant amplitude sequence at intervals of half the sequence length to obtain an observation value C containing fractional frequency offset information. Based on the observation value C, the acquisition of the frequency offset value is converted into a division operation and an inverse trigonometric operation.

[0098] Step 4: Determine the I-Q size of the above observed value C and confirm the divisor, dividend and quadrant. The quadrant is confirmed by the four-quadrant and corresponding angle table.

[0099] Step 5: numerically scale the divisor and the dividend so that the divisor value just fills the reciprocal operation. The numerical scaling refers to shifting the values ​​of the I and Q paths by binary.

[0100] Step 6: Decompose the divisor into integer and decimal parts based on the Taylor expansion method, perform table lookup and multiplication and addition operations according to the first-order Taylor expansion method, and multiply it with the dividend to complete the division operation.

[0101] Step 7: Decompose the division result into high bits and low bits, and perform table lookup and multiplication and addition operations according to the first-order Taylor expansion method to complete the inverse tangent function operation, wherein the low bits and high bits can be set as needed.

[0102] Step 8: Restore the calculation result of step 7 according to the quadrant judgment result, so as to obtain a coarse frequency offset estimation value.

[0103] It can be understood that the technical solution disclosed in the present invention optimizes the rough frequency offset estimation operation in consideration of both performance and feasibility, and provides an implementation method. It can adapt to communication applications with different hardware computing power conditions, provide underlying computing support for complex frequency offset estimation methods, and solve the problem of insufficient accuracy or excessive resource overhead caused by nonlinear functions in frequency offset estimation operations.

[0104] The present disclosure also provides a coarse frequency offset estimation device 400, such as Figure 4 As shown, the coarse frequency offset estimation device 400 comprises at least: a first unit 410, a second unit 420 and a third unit 430, wherein:

[0105] The first unit 410 is configured to obtain an observation value including frequency offset information based on a received primary synchronization signal, wherein the observation value includes an I-path observation value and a Q-path observation value.

[0106] The second unit 420 is used to calculate a division term based on the I-path observation value and the Q-path observation value to obtain a division result, wherein the dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and the divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value.

[0107] The third unit 430 is configured to calculate an inverse tangent function for the division result to obtain a frequency offset estimation value.

[0108] The device further comprises at least one of the following:

[0109] i) in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression including a term including the integer part and a term including the decimal part through Taylor series expansion, and the term including the integer part is obtained by looking up a first lookup table;

[0110] ii) In the process of obtaining the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression containing a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term containing the high-order part is obtained by looking up a second lookup table.

[0111] It can be understood that the above-mentioned coarse frequency offset estimation device can implement each step of the coarse frequency offset estimation method provided in the above-mentioned embodiment, and the relevant explanations about the coarse frequency offset estimation method are applicable to the coarse frequency offset estimation device, which will not be repeated here.

[0112] Although specific functions are discussed above with reference to specific units, it should be noted that the functions of the various units discussed herein can be divided into multiple units, and / or at least some functions of multiple units can be combined into a single unit. The specific unit discussed herein performs an action including the specific unit itself performing the action, or alternatively the specific unit calls or otherwise accesses another component or unit that performs the action (or performs the action in conjunction with the specific unit). Therefore, the specific unit that performs an action can include the specific unit itself that performs the action and / or another unit that the specific unit calls or otherwise accesses and performs the action.

[0113] It should also be understood that various techniques may be described herein in the general context of software hardware elements or program units. Figure 4 The various units described may be implemented in hardware or in hardware in combination with software and / or firmware. For example, these units may be implemented as computer program code / instructions configured to be executed in one or more processors and stored in a computer-readable storage medium. Alternatively, these units may be implemented as hardware logic / circuits.

[0114] The embodiment of the present disclosure also provides a computing device, including: at least one processor; and at least one memory storing instructions, which, when executed individually or collectively by the at least one processor, enable the computing device to execute the above-mentioned coarse frequency offset estimation method.

[0115] It should be noted that computing devices include but are not limited to terminal devices, base station devices (for example, ground base stations or satellite network devices), and devices that can implement the above-mentioned coarse frequency offset estimation method all fall within the protection scope of the present disclosure.

[0116] The embodiment of the present disclosure also provides a computer storage medium storing instructions, wherein the instructions, when executed individually or collectively by at least one processor of a computing device, cause the computing device to execute the above-mentioned coarse frequency offset estimation method.

[0117] The embodiment of the present disclosure further provides a computer program product, comprising instructions, which, when executed individually or collectively by at least one processor of a computing device, enable the computing device to execute the above-mentioned coarse frequency offset estimation method.

[0118] An embodiment of the present disclosure further provides a chip, which includes a circuit system configured to execute the above-mentioned coarse frequency offset estimation method.

[0119] In order to better illustrate the computational accuracy of the coarse frequency offset estimation in the present disclosure, refer to Figure 5 , a comparison chart of the direct table lookup method and the disclosed technical solution in terms of the rough frequency offset estimation calculation accuracy is given, the table lookup address is 8 bits, the input data uses the PSS of mode D, and the calculation accuracy is defined as the absolute value of the error between the actual phase angle calculation result and the theoretical result. Figure 5 As shown, the horizontal axis is the actual ratio of Q path to I path (assuming that the absolute value of Q path is less than the absolute value of I path), and the vertical axis is the calculation accuracy. As can be seen from the figure, within all possible input ranges, the calculation accuracy of the disclosed technical solution is an order of magnitude lower than that of the existing solution. The disclosed technical solution (left) improves the calculation performance in terms of calculation accuracy compared to the table lookup method (right) of the same level.

[0120] Figure 6 This is a simulation result diagram of the rough frequency offset estimation in the embodiment of the present disclosure. It can be seen from the figure that the Verilog simulation result of the operation speed of the technical solution of the present disclosure uses only 2 conjugate multipliers and 3 multipliers in DSP resource overhead. Under the working clock of 122.88MHz, after the captured PSS signal arrives completely, it only takes about 400ns to obtain the rough frequency offset estimation operation result.

[0121] In summary, with the storage resources of an 8-bit table lookup address and a small amount of DSP resource overhead, the computing speed of the disclosed technical solution is at the microsecond level, and the computing accuracy is better than the table lookup method of the same level, while taking into account both performance and feasibility.

[0122] Figure 77 is a simplified block diagram of a computing device 700 suitable for implementing embodiments of the present disclosure. As shown, the computing device 700 includes one or more processors 710, one or more memories 720 coupled to the processors 710, and one or more communication modules 740 coupled to the processors 710.

[0123] The communication module 740 is used for two-way communication. The communication module 740 has at least one antenna to facilitate communication. The communication interface may represent any interface necessary for communicating with other network elements.

[0124] Processor 710 may be of any type suitable for the local technology network, and may include, as non-limiting examples, one or more of: a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Computing device 700 may have multiple processors, such as application specific integrated circuit chips, which are driven in time to a clock that synchronizes a master processor.

[0125] The memory 720 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 724, electrically programmable read-only memory (EPROM), flash memory, hard disk, compact disk (CD), digital video disk (DVD), and other magnetic and / or optical memories. Examples of volatile memories include, but are not limited to, random access memory (RAM) 722 and other volatile memories that do not persist during a power outage.

[0126] The computer program 730 includes computer executable instructions that are executed by the associated processor 710. The program 730 may be stored in the ROM 724. The processor 710 may perform any appropriate actions and processes by loading the program 730 into the RAM 722.

[0127] The embodiments of the present disclosure may be implemented by a program 730, so that the computing device 700 may execute the reference Figure 1 Any process of the disclosure discussed. The embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0128] In some embodiments, the program 730 may be tangibly embodied in a computer-readable medium, which may be contained in the computing device 700 (e.g., memory 720) or other storage device accessible to the computing device 700. The computing device 700 may load the program 730 from the computer-readable medium to the RAM 722 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. The computer-readable medium has the program 730 stored thereon.

[0129] Generally, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are shown and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware or controllers or other computing devices, or some combination thereof.

[0130] The present disclosure also provides at least one computer program product tangibly stored on a non-transient computer-readable storage medium. The computer program product includes computer executable instructions, such as instructions included in program modules, which are executed in a device on a target real or virtual processor. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of program modules can be combined or separated between program modules as needed. Machine executable instructions for program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in local and remote storage media.

[0131] The program code for executing the disclosed method can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing equipment so that when the program code is executed by the processor or controller, the function / operation specified in the flow chart and / or block diagram is realized. The program code can be executed completely on the machine as an independent software package, partially on the machine, partially on the machine, partially on a remote machine, partially on a remote machine, or all on a remote machine or server.

[0132] In the context of the present disclosure, computer program codes or related data may be carried by any appropriate carrier to enable a device, apparatus or processor to perform various processes and operations as described above. Examples of carriers include signals, computer readable media, etc.

[0133] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or apparatuses, or any suitable combination of the foregoing. More specific examples of computer readable storage media include an electrical connection having one or more conductors, a portable computer floppy disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or 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 foregoing.

[0134] In addition, although the operations are described in a specific order, this should not be understood as requiring the specific order or sequence shown to be performed, or performing all the operations shown, to obtain the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these details should not be interpreted as limitations on the scope of the present disclosure, but can be interpreted as descriptions of features specific to a particular embodiment. Certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0135] Although the disclosure has been described in language specific to structural features and / or methodological acts, it should be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

[0136] It should be fully understood that the use of personally identifiable information should comply with industry standards generally considered to meet or exceed standards for maintaining user privacy. In particular, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

Claims

1. A method for estimating a coarse frequency offset for wireless communication, characterized in that: include: Based on the received primary synchronization signal, an observation value including frequency offset information is obtained, wherein the observation value includes an I-path observation value and a Q-path observation value; Calculating a division term based on the I-path observation value and the Q-path observation value to obtain a division result, wherein a dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and a divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value; Calculating an inverse tangent function for the division result to obtain a frequency deviation estimate; The method further comprises at least one of the following: i) in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression including a term including the integer part and a term including the decimal part through Taylor series expansion, and the term including the integer part is obtained by looking up a first lookup table; ii) In the process of obtaining the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression containing a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term containing the high-order part is obtained by looking up a second lookup table.

2. The method according to claim 1, characterized in that The reciprocal of the divisor is expressed by Taylor series expansion as: ， in, is the divisor, is the integer part, is the decimal part, including The entry is obtained by looking up the first lookup table.

3. The method according to claim 1, characterized in that The inverse tangent function of the division result is expressed by Taylor series expansion as: ， in, is the division result, is the high portion, is the low part, M is the low The maximum value of The entry is obtained by looking up the second lookup table.

4. The method according to any one of claims 1 to 3, characterized in that Also includes: Before calculating the division term based on the I-path observation value and the Q-path observation value, the I-path observation value and the Q-path observation value are binary shifted so that the first '1' bit of the integer part of the divisor from high to low is shifted to the highest bit of the integer part.

5. The method according to any one of claims 1 to 3, characterized in that Also includes: Before calculating the division term based on the I-path observation value and the Q-path observation value, according to the size relationship between the I-path observation value and the Q-path observation value, one of the I-path observation value and the Q-path observation value is selected as the dividend, and the other of the I-path observation value and the Q-path observation value is selected as the divisor; and After calculating the inverse tangent function of the division result to obtain the frequency offset estimate, the frequency offset estimate is adjusted according to the size relationship between the I-path observation value and the Q-path observation value so that the adjusted frequency offset estimate falls within the range of [0,π / 4].

6. The method according to claim 5, characterized in that The frequency offset estimation value is adjusted according to the following table: 。 7. The method according to any one of claims 1 to 3, characterized in that The obtaining, based on the received primary synchronization signal, an observation value including frequency offset information comprises: Performing conjugate point multiplication of the master synchronization signal and the corresponding local master synchronization signal to obtain a constant amplitude sequence; A delayed correlation operation is performed on the constant amplitude sequence to obtain the observation value containing the frequency offset information.

8. A Doppler frequency deviation estimation device for wireless communication, characterized in that: include: A first unit is used to obtain an observation value including frequency offset information based on a received primary synchronization signal, wherein the observation value includes an I-path observation value and a Q-path observation value; a second unit, configured to calculate a division term based on the I-path observation value and the Q-path observation value to obtain a division result, wherein a dividend of the division term is selected from one of the I-path observation value and the Q-path observation value, and a divisor of the division term is selected from the other of the I-path observation value and the Q-path observation value; The third unit is used to calculate the inverse tangent function of the division result to obtain a frequency deviation estimate; The device further comprises at least one of the following: i) in the process of calculating the division term, the divisor includes an integer part and a decimal part, the reciprocal of the divisor is represented as an expression including a term including the integer part and a term including the decimal part through Taylor series expansion, and the term including the integer part is obtained by looking up a first lookup table; ii) In the process of obtaining the inverse tangent function, the division result includes a high-order part and a low-order part, and the inverse tangent function of the division result is represented as an expression containing a term of the high-order part and a term of the low-order part through Taylor series expansion, and the term containing the high-order part is obtained by looking up a second lookup table.

9. A computing device, characterized in that include: at least one processor; as well as At least one memory storing instructions thereon, which, when executed individually or collectively by the at least one processor, cause the computing device to perform the method according to any one of claims 1 to 7.

10. A computer storage medium storing instructions, characterized in that: When the instructions are executed individually or collectively by at least one processor of a computing device, the computing device is caused to perform the method according to any one of claims 1 to 7.

11. A computer program product comprising instructions, characterized in that When the instructions are executed individually or collectively by at least one processor of a computing device, the computing device is caused to perform the method according to any one of claims 1 to 7.

12. A chip, characterized in that: The chip comprises a circuit system configured to perform the method according to any one of claims 1 to 7.

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