Resampling method and device, chip, terminal equipment and storage medium

Abstract

The invention discloses a resampling method and device, a chip, terminal equipment and a storage medium. The method comprises the steps that the sampling frequency of baseband equipment is acquired; acquiring a reference clock frequency and a clock frequency offset of a crystal oscillator of the digital-to-analog converter; according to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset, determining the resampling step length through a Taylor expansion of a resampling step length calculation function at the reference clock frequency, the value of the Taylor coefficient of the Taylor expansion is determined based on the reference clock frequency look-up table; and resampling the sampling frequency of the baseband equipment according to the resampling step length so as to adapt to the sampling frequency of the digital-to-analog converter.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of communication technology, and more specifically, to a resampling method and apparatus, a chip, a terminal device, and a storage medium. Background Art

[0002] In wireless communication systems, before a digital baseband signal enters a digital to analog converter (DAC) for conversion into an analog signal, it is usually necessary to resample the sampling frequency of the baseband device one or more times based on the resampling step size to adapt to the sampling frequency of the DAC.

[0003] For resampling, the most important parameter is the resampling step size. Currently, the calculation of the resampling step size mainly calls the division operation, which makes the calculation of the resampling step size time-consuming and energy-intensive. Summary of the invention

[0004] The embodiments of the present application provide a resampling method and apparatus, a chip, a terminal device, and a storage medium. The following introduces various aspects involved in the embodiments of the present application.

[0005] In a first aspect, a resampling method is provided, comprising: obtaining a sampling frequency of a baseband device; obtaining a reference clock frequency and a clock frequency offset of a crystal oscillator of a digital-to-analog converter; determining the resampling step size according to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset by calculating a Taylor expansion of a resampling step size calculation function at the reference clock frequency, wherein the value of the Taylor coefficient of the Taylor expansion is determined by looking up a table based on the reference clock frequency; and resampling the sampling frequency of the baseband device according to the resampling step size to adapt to the sampling frequency of the digital-to-analog converter.

[0006] In a second aspect, a resampling device is provided, comprising: a first acquisition module, used to acquire the sampling frequency of a baseband device; a second acquisition module, used to acquire the reference clock frequency and clock frequency offset of the crystal oscillator of a digital-to-analog converter; a determination module, used to determine the resampling step size according to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset, by calculating the Taylor expansion of a resampling step size calculation function at the reference clock frequency, wherein the value of the Taylor coefficient of the Taylor expansion is determined by looking up a table based on the reference clock frequency; and a resampling module, used to resample the sampling frequency of the baseband device according to the resampling step size to adapt to the sampling frequency of the digital-to-analog converter.

[0007] In a third aspect, a chip is provided, comprising: a processor, configured to call and run a computer program from a memory, so that a device equipped with the chip executes the method described in the first aspect.

[0008] In a fourth aspect, a terminal device is provided, comprising a processor, a memory and a transceiver, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to control the terminal device to execute the method described in the first aspect.

[0009] According to a fifth aspect, a computer-readable storage medium is provided, on which executable code is stored. When the executable code is executed, the method described in the first aspect can be implemented.

[0010] The embodiment of the present application provides a resampling method, which can determine the resampling step size according to the sampling frequency, reference clock frequency and clock frequency offset of the baseband device through the Taylor expansion of the resampling step size calculation function at the reference clock frequency and the value of the pre-stored Taylor coefficient. Then, according to the resampling step size, the sampling frequency of the baseband device can be resampled to adapt to the sampling frequency of the digital-to-analog converter. Compared with the traditional solution of directly determining the resampling step size through division operation, this solution can determine the value of the Taylor coefficient by looking up a table while maintaining the calculation accuracy. Furthermore, the resampling step size is determined by the Taylor expansion of the resampling step size calculation function at the reference clock frequency, which can avoid the call of the division operation, thereby helping to reduce the calculation time of the resampling step size and reduce the calculation energy consumption of the resampling step size. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of a wireless communication system applied in an embodiment of the present application.

[0012] Figure 2 It is a schematic diagram of the structure of a baseband system provided in one embodiment of the present application.

[0013] Figure 3 It is a flowchart of a resampling method provided in an embodiment of the present application.

[0014] Figure 4 It is a simulation diagram of the loss error of the resampling step provided in one embodiment of the present application.

[0015] Figure 5 It is a simulation diagram of the loss error of the resampling step provided in another embodiment of the present application.

[0016] Figure 6 It is a structural diagram of a resampling device provided in one embodiment of the present application.

[0017] Figure 7 It is a structural diagram of a terminal device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0019] First, the application scenarios involved in the embodiments of the present application are introduced.

[0020] Communication System

[0021] The embodiments of the present application can be applied to various communication systems. For example, the embodiments of the present application can be applied to global system of mobile communication (GSM) system, code division multiple access (CDMA) system, synchronous code division multiple access (SCDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, advanced long term evolution (LTE-A) system, new radio (NR) system, NR system evolution system, LTE-based access to unlicensed spectrum (LTE-U) system, NR-based access to unlicensed spectrum (NR-U) system, universal mobile telecommunication system (UMTS), wireless local area networks (WLAN), wireless fidelity (WiFi), and fifth-generation communication (5G) system. The embodiments of the present application may also be applied to other communication systems, such as future communication systems, which may be, for example, sixth-generation (6G) mobile communication systems or satellite communication systems.

[0022] Traditional communication systems support a limited number of connections and are easy to implement. However, with the development of communication technology, communication systems can not only support traditional cellular communications, but also support one or more other types of communications. For example, a communication system can support one or more of the following communications: device to device (D2D) communication, machine to machine (M2M) communication, machine type communication (MTC), vehicle to vehicle (V2V) communication, and vehicle to everything (V2X) communication, etc. The embodiments of the present application can also be applied to communication systems that support the above-mentioned communication methods.

[0023] The communication system in the embodiment of the present application can be applied to a carrier aggregation (CA) scenario, a dual connectivity (DC) scenario, or a standalone (SA) networking scenario.

[0024] The communication system in the embodiment of the present application can be applied to an unlicensed spectrum. The unlicensed spectrum can also be considered as a shared spectrum. Alternatively, the communication system in the embodiment of the present application can also be applied to an authorized spectrum. The authorized spectrum can also be considered as a dedicated spectrum.

[0025] The embodiments of the present application can be applied to a terrestrial communication network (TN) system, and can also be applied to a non-terrestrial network (NTN) system. As an example, the NTN system can include an NR-based NTN system and an Internet of Things (IoT)-based NTN system.

[0026] The communication system may include one or more terminal devices. The terminal devices mentioned in the embodiments of the present application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device, etc.

[0027] In some embodiments, the terminal device may be a station (STATION, ST) in a WLAN. In some embodiments, the terminal device may also be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA) device, a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a next-generation communication system (such as an NR system), or a terminal device in a future-evolved public land mobile network (PLMN) network, etc.

[0028] In some embodiments, the terminal device may refer to a device that provides voice and / or data connectivity to the user. For example, the terminal device may be a handheld device, a vehicle-mounted device, etc. with a wireless connection function. As some specific examples, the terminal device may be a mobile phone, a tablet computer (Pad), a laptop computer, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc.

[0029] In some embodiments, the terminal device can be deployed on land. For example, the terminal device can be deployed indoors or outdoors. In some embodiments, the terminal device can be deployed on the water, such as on a ship. In some embodiments, the terminal device can be deployed in the air, such as on an airplane, a balloon, and a satellite.

[0030] In addition to the terminal device, the communication system may also include one or more network devices. The network device in the embodiment of the present application may be a device for communicating with the terminal device, and the network device may also be referred to as an access network device or a radio access network device. The network device may be, for example, a base station. The network device in the embodiment of the present application may refer to an access network (radio access network, RAN) node (or device) that connects the terminal device to a wireless network. Access network equipment can broadly cover various names as follows, or be replaced with the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, access point, transmission point (TRP), transmission point (TP), master station MeNB, secondary station SeNB, multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, base band unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. The base station can be a macro base station, a micro base station, a relay node, a donor node or the like, or a combination thereof. The base station may also refer to a communication module, modem or chip used to be set in the aforementioned device or apparatus. The base station may also be a mobile switching center and a device to device D2D, vehicle-to-everything (V2X), machine-to-machine (M2M) communication device that performs the base station function, a network side device in a 6G network, and a device that performs the base station function in a future communication system. The base station may support networks with the same or different access technologies. The embodiments of the present application do not limit the specific technology and specific device form adopted by the network equipment.

[0031] Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move based on the location of the mobile base station. In other examples, a helicopter or drone can be configured to act as a device that communicates with another base station.

[0032] In some deployments, the network device in the embodiments of the present application may refer to a CU or a DU, or the network device includes a CU and a DU. The gNB may also include an AAU.

[0033] As an example and not limitation, in an embodiment of the present application, the network device may have a mobile characteristic, for example, the network device may be a mobile device. In some embodiments of the present application, the network device may be a satellite or a balloon station. For example, the satellite may be a low earth orbit (LEO) satellite, a medium earth orbit (MEO) satellite, a geostationary earth orbit (GEO) satellite, a high elliptical orbit (HEO) satellite, etc. In some embodiments of the present application, the network device may also be a base station set up in a location such as land or water.

[0034] In an embodiment of the present application, a network device may provide services for a cell, and a terminal device may communicate with the network device through transmission resources (e.g., frequency domain resources, or spectrum resources) used by the cell. The cell may be a cell corresponding to a network device (e.g., a base station). The cell may belong to a macro base station or a base station corresponding to a small cell. The small cells here may include: metro cells, micro cells, pico cells, femto cells, etc. These small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services.

[0035] For example, Figure 1 The following is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application. Figure 1 As shown, the communication system 100 may include a network device 110, which may be a device that communicates with a terminal device 120 (or a communication terminal or terminal). The network device 110 may provide communication coverage for a specific geographic area and may communicate with terminal devices located in the coverage area.

[0036] Figure 1 An exemplary diagram shows one network device 110 and two terminal devices 120. In some embodiments of the present application, the communication system may include any number of network devices 110, and each network device 110 may include any number of terminal devices within its coverage area. The embodiments of the present application do not limit the number of network devices 110 and terminal devices 120 in the communication system 100.

[0037] It should be understood that the device with communication function in the network / system in the embodiment of the present application can be referred to as a communication device. Figure 1 Taking the communication system 100 shown as an example, the communication device may include a network device 110 and a terminal device 120 with communication functions, and the network device 110 and the terminal device 120 may be the specific devices described above, which will not be repeated here. The communication device may also include other devices in the communication system 100, such as a network controller, a mobile management entity, and other network entities, which are not limited in the embodiments of the present application.

[0038] In any of the wireless communication systems described above (such as an LTE system or an NR system), it is necessary to convert the digital baseband signal into an analog signal before wireless communication. The conversion of the digital baseband signal into an analog signal can be achieved by a digital-to-analog converter DAC. The sampling frequency of the DAC is controlled by a crystal oscillator, and the clock frequency output by the crystal oscillator is affected by various factors such as temperature. For a crystal oscillator of good quality, the deviation of its output clock frequency is usually less than 0.5 millionths. Taking a DAC sampling frequency of 200MHz as an example, a deviation of 0.5 millionths is 100Hz, which means that the deviation of the number of sampling points output per second can reach 100.

[0039] Therefore, before the digital baseband signal enters the digital-to-analog converter DAC and is converted into an analog signal, the resampling step size needs to be periodically adjusted according to the measured deviation of the crystal oscillator clock. In other words, the sampling frequency of the baseband device usually needs to be resampled once or multiple times based on the resampling step size to adapt to the sampling frequency of the DAC.

[0040] The following takes the baseband system in the terminal device as an example. Figure 2 The resampling process in the baseband system is described by way of example. The terminal device may be any type of terminal device mentioned above.

[0041] like Figure 2 As shown, the baseband system 200 may include a baseband device 210 , a resampling filter 220 , and a digital-to-analog converter 230 .

[0042] The baseband device 210 may be used to generate a digital baseband signal; the resampling filter 220 may be used to adjust the frequency of the digital baseband signal from a first frequency to a second frequency; and the digital-to-analog converter 230 may be used to convert the digital baseband signal of the second frequency into an analog signal. The second frequency matches the sampling frequency of the digital-to-analog converter 230. In some embodiments, the baseband device 210 may refer to a module that generates a digital baseband signal, such as a baseband chip, which is not specifically limited in the present application.

[0043] In some embodiments, the first frequency may refer to the sampling frequency of the baseband device. The first frequency may be referred to as the resampled input sampling frequency f in , the second frequency can be called the resampled output sampling frequency f out . Then the resampling step size T step Can be:

[0044]

[0045] Since the crystal oscillator is affected by the external environment such as temperature, its output clock frequency will produce frequency deviation. Therefore, in many cases, the resampled output sampling frequency may not be an integer. At present, resampling is usually achieved by interpolation, such as Lagrange interpolation, B-spline interpolation, etc. For resampling interpolation, the most important parameter is the resampling step size. However, the current calculation of the resampling step size is mainly based on the division operation. This results in the calculation of the resampling step being time-consuming and consuming a lot of computational energy.

[0046] In order to solve the above problems, an embodiment of the present application provides a resampling method, which can determine the resampling step size according to the sampling frequency, reference clock frequency and clock frequency offset of the baseband device through the Taylor expansion of the resampling step size calculation function at the reference clock frequency and the value of the pre-stored Taylor coefficient. Then, according to the resampling step size, the sampling frequency of the baseband device can be resampled to adapt to the sampling frequency of the digital-to-analog converter. Compared with the traditional solution of directly determining the resampling step size by division operation, this solution can determine the value of the Taylor coefficient by looking up a table while maintaining the calculation accuracy. Furthermore, the resampling step size is determined by the Taylor expansion of the resampling step size calculation function at the reference clock frequency, which can avoid the call of the division operation, thereby helping to reduce the calculation time of the resampling step size and reduce the calculation energy consumption of the resampling step size.

[0047] Combined with the following Figure 3 The resampling method in the embodiment of the present application is described in detail. Figure 3 As shown, the resampling method 300 may include steps: S310 to S340.

[0048] In step S310, the sampling frequency of the baseband device is obtained.

[0049] In some embodiments, the baseband device may refer to a module for generating a digital baseband signal, for example, a baseband chip, and the present application does not impose any specific limitation on this.

[0050] In some embodiments, the baseband device may be used to generate a digital baseband signal, and the sampling frequency of the baseband device may refer to the frequency of the digital baseband signal.

[0051] The sampling frequency of the baseband device may refer to the number of samples extracted from the continuous signal per second to form a discrete signal. The sampling frequency may be expressed in Hertz (Hz). The sampling rate may be, for example, 245760000 Hz or 7680000 Hz, and this application does not impose any specific restrictions on this.

[0052] The embodiment of the present application does not impose any specific restrictions on the method of obtaining the sampling frequency of the baseband device. For example, it can be obtained from the instruction manual of the baseband device, or by testing the sampling frequency of the baseband device using a sampling rate test instrument.

[0053] In step S320, the reference clock frequency and clock frequency offset of the crystal oscillator of the digital-to-analog converter are obtained.

[0054] It is understandable that the sampling rate of the digital-to-analog converter is mainly controlled by the crystal oscillator in the digital-to-analog converter, and the clock frequency output by the crystal oscillator can be called the reference clock frequency. When the crystal oscillator is affected by various factors such as temperature, the clock frequency output by the crystal oscillator may be offset, and the offset of the clock frequency output by the crystal oscillator can also be referred to as clock frequency offset.

[0055] It should be noted that, currently, several fixed reference clock frequencies are usually used in digital-to-analog converters. The reference clock frequency may be, for example, 249600000 Hz or 66560000 Hz. In some embodiments, the reference clock frequency may be obtained from the instruction manual of the digital-to-analog converter, or the sampling frequency of the digital-to-analog converter may be tested using a sampling rate tester to obtain the reference clock frequency.

[0056] In some embodiments, since the clock frequency offset is an irregular variable (it should be understood that its change is mainly related to ambient environmental factors such as temperature), it is necessary to continuously test the clock frequency offset. For example, a sampling rate test instrument can be used to test the sampling frequency of the digital-to-analog converter to obtain the clock frequency offset.

[0057] In some embodiments, the clock frequency offset is usually expressed as a percentage based on the reference clock frequency. For example, the clock frequency offset may be 0.5 parts per million, that is, the clock frequency offset is equal to the reference clock frequency multiplied by 5*10 ―6 .

[0058] It should be noted that the actual sampling frequency of the digital-to-analog converter is equal to the sum of the reference clock frequency and the clock frequency offset.

[0059] In step S330, the resampling step size is determined based on the sampling frequency, reference clock frequency and clock frequency offset of the baseband device by using the Taylor expansion of the resampling step size calculation function at the reference clock frequency, wherein the Taylor coefficient of the Taylor expansion is determined by looking up the table based on the reference clock frequency.

[0060] In some embodiments, the resampling step size T step Can be:

[0061]

[0062] Among them, f in is the sampling frequency of the baseband device, f out is the sampling frequency of the digital-to-analog converter, f in The resampled input sampling frequency, f out The output sampling frequency of the resampled sample can be called is the resampling step calculation function, f a is the reference clock frequency, x is the clock frequency offset, The Taylor expansion of the resampling step calculation function at the reference clock frequency is, is the Taylor coefficient, and k is a positive integer.

[0063] According to formula (2), we can see that as long as we store the value of the Taylor coefficient in advance, we can then determine the corresponding Taylor coefficient by looking up the table according to the reference clock frequency. Furthermore, the resampling step size can be determined, and the calling of the division operation can be avoided, thereby reducing the calculation time of the resampling step size and reducing the calculation energy consumption of the resampling step size.

[0064] In some embodiments, the values ​​of the Taylor coefficients can be stored in advance, and then the values ​​of the Taylor coefficients can be determined based on the reference clock frequency and the mapping relationship between the reference clock frequency and the values ​​of the Taylor coefficients of the Taylor expansion; then, based on the sampling frequency of the baseband device, the values ​​of the Taylor coefficients and the clock frequency offset, the resampling step size can be determined through multiplication and addition operations.

[0065] In some embodiments, the resampling step size T can be constrained step <1, so that the processor can be used for fixed-point calculation, improving the controllability and amount of calculation. It should be understood that if floating-point calculation is used, it will be more complicated and the controllability of the calculation will be poor.

[0066] In step S340, the sampling frequency of the baseband device is resampled according to the resampling step size to adapt to the sampling frequency of the digital-to-analog converter.

[0067] In some embodiments, after the resampling step size is determined, the sampling frequency of the baseband device can be resampled using a resampling filter. For example, the sampling frequency f of the baseband device can be resampled by resampling. in Convert to sampling frequency f out , to adapt the sampling frequency of the digital-to-analog converter, thereby improving the transmission accuracy of the baseband data.

[0068] It should be noted that the resampling step requires a very high calculation accuracy, for example, the calculation accuracy can be 30-40 bits. If the clock frequency offset x is less than 0.5 parts per million, that is, the clock frequency offset satisfies:

[0069] x <f a *5*10 ―6 (3)

[0070] If only the first-order Taylor expansion is performed on formula (2), the resampling step length T step Can be:

[0071]

[0072] Among them, the first-order Taylor expansion can include two terms, the first term is The second item is

[0073] According to the Taylor expansion in formula (2), the third term is Furthermore, according to the properties of Taylor expansion and the Taylor expansion in formula (2), the sum of the third term to the k+1th term is less than the third term That is to say, the resampling step length is determined by the first-order Taylor expansion of the resampling step length calculation function at the reference clock frequency, and the loss error S of the resampling step length is t is smaller than the third term, that is, S t satisfy:

[0074]

[0075] If we use the processor to perform fixed-point calculations and then substitute formula (3) into formula (5), we can get:

[0076]

[0077] Further, we can get:

[0078] S t <25*10 ―12 <2 ―35 (7)

[0079] According to the above formula, the resampling step size is determined by the first-order Taylor expansion of the resampling step size calculation function at the reference clock frequency. The loss error of the resampling step size is less than 35 bits, which can meet the calculation accuracy requirements. It can be understood that the loss error result here is the upper bound of the loss error, not the supremum, and the actual loss error is lower than this result.

[0080] Based on the above loss error results, it can be known that in the embodiment of the present application, the resampling step size can be determined by the first-order Taylor expansion of the resampling step size calculation function at the reference clock frequency. That is, the resampling step size can be calculated and determined according to formula (4), where: and is the Taylor coefficient.

[0081] In some embodiments, in order to pursue a higher precision approximation, the scheme in the embodiment of the present application can determine the resampling step size by the second-order Taylor expansion of the resampling step size calculation function at the reference clock frequency. Alternatively, the resampling step size can also be determined by the third-order Taylor expansion of the resampling step size calculation function at the reference clock frequency, and the present application does not make specific restrictions on this.

[0082] In some embodiments, in order to improve data calculation accuracy, the pre-stored Taylor coefficient values ​​may be processed, for example, padding may be performed to make the bit width of the Taylor coefficient values ​​the maximum bit width that the processor can process.

[0083] As an example, if the current processor is a 64-bit processor and the base clock frequency f a is 249600000 Hz, then we can deduce: Then you can Perform padding processing (e.g., shift processing) so that The bit width of the value is the maximum bit width that the processor can handle. For example, for a 64-bit processor, The maximum padding width for padding is q, which ideally satisfies: Right now, Furthermore, it can be deduced that: ―(64―q) <2 ―27 , that is, ―(64―q)<―27, that is, q<37. The padding width of is an integer, so The maximum padding width is 36 bits.

[0084] It should be understood that in order to improve the data calculation accuracy, the values ​​of the Taylor coefficients after padding using the maximum padding bit width may be stored for subsequent table lookup and retrieval.

[0085] It should be noted that after the resampling step length is calculated using the padded Taylor coefficients, a reverse shift process can be performed to restore the actual calculated value of the resampling step length.

[0086] In some embodiments, since the sampling frequency of the baseband device is a positive integer, in order to facilitate calculation, the value of each Taylor coefficient can be first converted to a positive integer, and then the converted Taylor coefficient can be padded so that the bit width of the Taylor coefficient value is the maximum bit width that the processor can handle.

[0087] As an example, if the current processor is a 64-bit processor and the base clock frequency f a is 249600000 Hz, then we can deduce: We can first use the Taylor coefficient Convert to a positive integer, for example by shifting it first Among them, the bit width 64 is the maximum processing capability of the processor; then, Perform padding processing (e.g., shift processing) so that The value of is a positive integer, and the bit width of the value is the maximum bit width that the processor can handle. Before the padding process, the padding value f0 can be constructed and satisfies: f0 = 2 p <f a , we can infer that the maximum padding width p is 27. Further, we can use f0 to After padding, the Taylor coefficient is Finally, the value of the Taylor coefficient after padding can be rounded, that is, Therefore, the value of the Taylor coefficient after conversion into a positive integer can also reach the maximum bit width that a 64-bit processor can handle.

[0088] It should be understood that, in order to facilitate calculation, the values ​​of the processed Taylor coefficients may be stored in advance for subsequent table lookup.

[0089] It should be noted that after the resampling step length is calculated using the processed Taylor coefficients, a reverse shift process can be performed to restore the actual calculated value of the resampling step length.

[0090] At present, the sampling frequency f of the baseband equipment in They are all integer multiples of 2.56MHz, and 2.56MHz is an integer multiple of 4096Hz, 4096=2 12 This means that the sampling frequency f of the baseband device in There is no loss of precision after a 12-bit right shift.

[0091] Based on the above analysis, in some embodiments, the sampling frequency f of the baseband device is constructed. in The binary common divisor f b , some multiplication operations in the resampling step can be converted into shift operations, which can further reduce the computational complexity of the resampling step and reduce the computational energy consumption of the resampling step.

[0092] It should be understood that the present embodiment of the present application has a binary common divisor f b There is no specific restriction on the value of b It can also be a value such as 2048, 1024, etc.

[0093] Taking formula (2) as an example, if f b =4096=2 12 , then the resampling step size T can be step Converts to:

[0094]

[0095] Among them, f in >>12 is a shift operation, representing the sampling frequency f of the baseband device in Shift right 12 bits.

[0096] In order to further understand the above resampling method, the Taylor expansion of the resampling step calculation function at the reference clock frequency is taken as the first-order Taylor expansion, f b =4096=2^12, f0=2 p <f a , taking the current processor as a 64-bit processor as an example, the resampling method is described in detail with examples, which may include the following steps.

[0097] Step 4.1: According to formula (4), and are all the values ​​of Taylor coefficients. For the convenience of calculation, the values ​​of Taylor coefficients can be processed by positive, rounding and padding, and the processed values ​​of Taylor coefficients θ and α can be obtained, which are:

[0098]

[0099]

[0100] Then, θ and α are pre-stored in a table so that the subsequent resampling step does not involve the division call operation of the processor.

[0101] Step 4.2: Based on formula (8), we can first obtain The calculation results

[0102]

[0103] According to the current reference clock frequency f a , we can look up θ and α in the table, and substitute θ and α into formula (11), we can get:

[0104]

[0105] Among them, (θ―α*x)>>(p―12) is a shift operation, which means that (θ―α*x) is shifted right by (p―12) bits.

[0106] Step 4.3: Substitute the results from step 4.2 into Substituting into formula (8), we can get:

[0107]

[0108] As can be seen, only multiplication and shift operations are involved here.

[0109] Based on the above embodiments, for the calculation of the resampling step length caused by the clock deviation, by using the Taylor coefficient value storage table and Taylor expansion approximation, a high resampling step length calculation accuracy can be achieved with very low fixed-point multiplication and addition calculation and storage overhead, avoiding the use of high-precision division and large-scale storage table (i.e., directly storing ), greatly reducing power consumption and computing resources.

[0110] According to the calculation process of the resampling step size from step 4.1 to step 4.3, two possible simulation results are given below.

[0111] Simulation result 1: If the reference clock frequency f a =249600000Hz, p=27, sampling frequency f of baseband equipment in =245760000Hz, the clock frequency offset x is -125:1:125Hz. Using the above resampling step calculation method, the resampling step T can be determined. step1 . Further, the loss error S of the resampling step is t1 Perform normalization, that is, The loss error result is as follows Figure 4 shown.

[0112] Simulation result 2: If the reference clock frequency f a =66560000Hz, p=25, sampling frequency f of baseband equipment in =7680000Hz, the clock frequency offset x is -33:1:33Hz. Using the above resampling step calculation method, the resampling step T can be determined. step2. Further, the loss error S of the resampling step is t2 Perform normalization, that is, The loss error result is as follows Figure 5 shown.

[0113] According to the above simulation results, it can be seen that the resampling step calculation method proposed in the embodiment of the present application can provide a calculation accuracy greater than 40 bits, which fully meets the actual usage requirements. It avoids division operations in the calculation process of the resampling step, thereby greatly reducing the calculation power consumption and computing resources of the resampling step.

[0114] It can be seen from the above content that by using parameter (ie, the value of Taylor expansion coefficient) storage table and Taylor expansion approximation, a higher resampling step calculation accuracy can be achieved with very low fixed-point multiplication and addition calculation and storage overhead.

[0115] It can be understood that the smaller the clock frequency offset is, the higher the calculation accuracy of the resampling step will be; and the larger the clock frequency offset is, the lower the calculation accuracy of the resampling step will be.

[0116] Combination of the above Figures 1 to 5 The method embodiment of the present application is described in detail. Figure 6 to Figure 7 The device embodiment of the present application is described in detail. It should be understood that the description of the method embodiment corresponds to the description of the device embodiment, so the parts not described in detail can refer to the previous method embodiment.

[0117] Figure 6 FIG. 6 is a schematic diagram of a resampling device according to an embodiment of the present application. The resampling device 600 may include: a first acquisition module 610 , a second acquisition module 620 , a determination module 630 and a resampling module 640 .

[0118] The first acquisition module 610 is used to obtain the sampling frequency of the baseband device.

[0119] The second acquisition module 620 is used to acquire the reference clock frequency and clock frequency offset of the crystal oscillator of the digital-to-analog converter.

[0120] The determination module 630 is used to determine the resampling step size according to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset, by calculating the Taylor expansion of the resampling step size calculation function at the reference clock frequency, wherein the value of the Taylor coefficient of the Taylor expansion is determined by looking up the table based on the reference clock frequency.

[0121] The resampling module 640 is used to resample the sampling frequency of the baseband device according to the resampling step size to adapt to the sampling frequency of the digital-to-analog converter.

[0122] Optionally, the determination module 630 is used to: determine the value of the Taylor coefficient based on the reference clock frequency and the mapping relationship between the reference clock frequency and the value of the Taylor coefficient of the Taylor expansion; determine the resampling step size through multiplication and addition operations based on the sampling frequency of the baseband device, the value of the Taylor coefficient and the clock frequency offset.

[0123] Optionally, the Taylor expansion of the resampling step calculation function at the reference clock frequency is a first-order Taylor expansion, and the resampling step is: Among them, T step is the resampling step size, is the resampling step calculation function, f in is the sampling frequency of the baseband device, f a is the reference clock frequency, x is the clock frequency offset, and is the Taylor coefficient.

[0124] Optionally, the bit width of the value of the Taylor coefficient is the maximum bit width that can be processed by the processor.

[0125] Optionally, the resampling step size is: Among them, T step is the resampling step size, f in is the sampling frequency of the baseband device, f b is the binary common divisor of the sampling frequency of the baseband device, f a is the reference clock frequency, and x is the clock frequency offset.

[0126] Combine the following Figure 7 This is an introduction to a terminal device 700 in an embodiment of the present application. The terminal device 700 can be used to implement the method described in the above method embodiment.

[0127] It should be understood that the terminal device 700 can be applied to any type of terminal device mentioned above.

[0128] The terminal device 700 may include one or more processors 710. The processor 710 may support the terminal device 700 to implement the method described in the above method embodiment.

[0129] The processor 710 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0130] The terminal device 700 may further include one or more memories 720. The memory 720 stores a program, which can be executed by the processor 710 to control the terminal device 700 to execute the method described in the above method embodiment. The memory 720 may be independent of the processor 710 or integrated in the processor 710.

[0131] The terminal device 700 may further include a transceiver 730. The processor 710 may communicate with other devices through the transceiver 730. For example, the processor 710 may transmit and receive data with other devices through the transceiver 730.

[0132] The present application also provides a chip in an embodiment, including a processor, which can be used to call and run a computer program from a memory, so that a device equipped with the chip performs the method described in the above method embodiment. It is understood that the processor can be any type of processor mentioned above. It is understood that the memory can be independent of the chip or integrated in the chip.

[0133] The embodiment of the present application also provides a machine-readable storage medium for storing a program, and the program enables a computer to execute the method in each embodiment of the present application.

[0134] The embodiment of the present application also provides a computer program product. The computer program product includes a program. The program enables a computer to execute the method in each embodiment of the present application.

[0135] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present disclosure is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a machine-readable storage medium, or transmitted from one machine-readable storage medium to another machine-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (Digital Subscriber Line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The machine-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0136] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments of the present disclosure can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present disclosure.

[0137] In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0138] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0139] In addition, each functional unit in each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0140] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A resampling method, characterized in that: include: Get the sampling frequency of the baseband device; Obtain the reference clock frequency and clock frequency offset of the crystal oscillator of the digital-to-analog converter; According to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset, the resampling step size is determined by a Taylor expansion of a resampling step size calculation function at the reference clock frequency, wherein the value of the Taylor coefficient of the Taylor expansion is determined by looking up a table based on the reference clock frequency; The sampling frequency of the baseband device is resampled according to the resampling step size to adapt to the sampling frequency of the digital-to-analog converter.

2. The method according to claim 1, characterized in that The determining the resampling step size by using a Taylor expansion of a resampling step size calculation function at the reference clock frequency according to the sampling frequency of the baseband device, the reference clock frequency, and the clock frequency offset comprises: Determine the value of the Taylor coefficient according to the reference clock frequency and the mapping relationship between the reference clock frequency and the value of the Taylor coefficient of the Taylor expansion; The resampling step size is determined through multiplication and addition operations according to the sampling frequency of the baseband device, the value of the Taylor coefficient and the clock frequency offset.

3. The method according to claim 1, characterized in that The Taylor expansion of the resampling step calculation function at the reference clock frequency is a first-order Taylor expansion, and the resampling step is: Among them, T step is the resampling step size, is the resampling step calculation function, f in is the sampling frequency of the baseband device, f a is the reference clock frequency, x is the clock frequency offset, and is the Taylor coefficient.

4. The method according to claim 2 or 3, characterized in that: The bit width of the Taylor coefficient value is the maximum bit width that the processor can handle.

5. The method according to any one of claims 1 to 3, characterized in that: The resampling step size is: Among them, T step is the resampling step size, f in is the sampling frequency of the baseband device, f b is the binary common divisor of the sampling frequency of the baseband device, f a is the reference clock frequency, and x is the clock frequency offset.

6. A resampling device, characterized in that: include: A first acquisition module, used to acquire a sampling frequency of a baseband device; A second acquisition module, used for acquiring a reference clock frequency and a clock frequency offset of a crystal oscillator of a digital-to-analog converter; A determination module, configured to determine the resampling step size according to the sampling frequency of the baseband device, the reference clock frequency and the clock frequency offset, by using a Taylor expansion of a resampling step size calculation function at the reference clock frequency, wherein the value of the Taylor coefficient of the Taylor expansion is determined by looking up a table based on the reference clock frequency; The resampling module is used to resample the sampling frequency of the baseband device according to the resampling step size to adapt the sampling frequency of the digital-to-analog converter.

7. The device according to claim 6, characterized in that The determination module is used for: Determine the value of the Taylor coefficient according to the reference clock frequency and the mapping relationship between the reference clock frequency and the value of the Taylor coefficient of the Taylor expansion; The resampling step size is determined through multiplication and addition operations according to the sampling frequency of the baseband device, the value of the Taylor coefficient and the clock frequency offset.

8. The device according to claim 6, characterized in that The Taylor expansion of the resampling step calculation function at the reference clock frequency is a first-order Taylor expansion, and the resampling step is: Among them, T step is the resampling step size, is the resampling step calculation function, f in is the sampling frequency of the baseband device, f a is the reference clock frequency, x is the clock frequency offset, and is the Taylor coefficient.

9. The device according to claim 7 or 8, characterized in that The bit width of the Taylor coefficient value is the maximum bit width that the processor can handle.

10. The device according to any one of claims 6 to 8, characterized in that The resampling step size is: Among them, T step is the resampling step size, f in is the sampling frequency of the baseband device, f b is the binary common divisor of the sampling frequency of the baseband device, f a is the reference clock frequency, and x is the clock frequency offset.

11. A chip, characterized in that: include: A processor, configured to call and run a computer program from a memory, so that a device equipped with the chip executes a method as claimed in any one of claims 1 to 5.

12. A terminal device, characterized in that: include: A processor, a memory and a transceiver, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to control the terminal device to execute the method as described in any one of claims 1 to 5.

13. A computer-readable storage medium having executable code stored thereon, characterized in that: The code is used to implement the method according to any one of claims 1 to 5.

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