An adaptive spectrum truncation method and device for a single-carrier frequency division multiple access system, a terminal and a medium

Abstract

The application discloses a kind of adaptive spectrum truncation method, device, terminal and medium for single-carrier frequency division multiple access system, method includes: obtaining the context information of current transmission;Based on context information, from the plurality of candidate truncation factors predefined, determine the target truncation factor used by current transmission, wherein the target truncation factor is the ratio of the target frequency domain sample number to be cut off and the original discrete fourier transform point number;The target truncation factor is synchronized to the transmitting device and the receiving device, and the target truncation factor is used to perform discrete fourier transform and spectrum truncation processing on the modulation symbol to be currently transmitted, to generate and send the final time-domain waveform signal.The application focuses on the lightweight adaptive mechanism of frequency domain sample truncation, determines the target truncation factor through context information, realizes the dynamic trade-off of spectral efficiency and transmission power under the premise of no machine learning training and no complex signaling interaction, and is especially suitable for devices sensitive to complexity and latency.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to an adaptive spectrum truncation method, apparatus, terminal, and medium for a single-carrier frequency division multiple access system. Background Technology

[0002] In 5G and its evolved communication systems, the uplink often employs Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) waveforms to reduce the peak-to-average power ratio (PAPR), thereby improving power amplifier efficiency and coverage. To further reduce the PAPR, existing technologies have proposed spectrum truncation techniques, which involve discarding (i.e., truncating) a portion of the subcarriers of the DFT-s-OFDM symbols in the frequency domain.

[0003] However, existing technologies have limitations in implementation: the truncation factor in existing technologies is usually set to one or more fixed preset values, or simply mapped based on static, coarse-grained attributes such as terminal type and service category (e.g., a fixed high truncation factor is assigned to IoT terminals). These solutions rely entirely on offline configuration and fail to utilize real-time contextual information available during each transmission, such as instantaneous channel state, user equipment's real-time power headroom report (PHR), and network dynamic scheduling parameters (e.g., MCS (modulation and coding scheme), number of allocated resource blocks). This static truncation strategy cannot adapt to dynamically changing wireless channel environments, user equipment states, and service requirements. Specifically, when channel quality is poor and user equipment is at the cell edge, a fixed truncation may lead to insufficient power gain, failing to effectively improve coverage; when channel quality is good, a fixed truncation may cause unnecessary spectral efficiency loss, limiting the improvement of peak rate. For example, in existing technologies, the truncation factor α uses a fixed value (e.g., 20%) or a simple mapping based on device type (e.g., 30% for IoT devices). Its drawback is that it cannot respond to real-time changes in channel conditions, resulting in insufficient power boost when the channel quality is poor, and unnecessary loss of spectral efficiency when the channel quality is good.

[0004] Therefore, existing technologies still have shortcomings. Summary of the Invention

[0005] To address the aforementioned deficiencies in the prior art, this invention provides an adaptive spectrum truncation method, apparatus, terminal, and medium for single-carrier frequency division multiple access systems. The technical solution adopted by this invention is as follows: In a first aspect, the present invention provides an adaptive spectrum truncation method for a single-carrier frequency division multiple access system, the method comprising: Obtain the context information of the current transmission; Based on the context information, the target truncation factor used in the current transmission is determined from a plurality of predefined candidate truncation factors, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform. Synchronize the target cutoff factor to the transmitting and receiving devices; The target truncation factor is used to perform discrete Fourier transform and spectral truncation on the modulation symbol to be transmitted, generating and sending the final time-domain waveform signal.

[0006] In one implementation, the context information includes any one or more of the following: channel state information, modulation and coding scheme level, number of allocated resource blocks or bandwidth, and power margin report of user equipment; wherein the channel state information is in the form of uplink channel quality estimation, precoding matrix indication, or channel matrix based on channel reciprocity estimation.

[0007] In one implementation, based on the context information, determining the target truncation factor for the current transmission from a predefined pool of candidate truncation factors includes: Based on the context information, a decision rule associated with the context information is established. Based on the decision rule, the target truncation factor to be used in the current transmission is determined from a plurality of predefined candidate truncation factors. or, Based on a pre-defined joint optimization model, the target truncation factor for the current transmission is determined from multiple predefined candidate truncation factors.

[0008] In one implementation, the decision rules include: a power priority rule, a spectrum priority rule, and a bandwidth adaptation rule; based on the decision rules, determining the target truncation factor for the current transmission from a plurality of predefined candidate truncation factors includes: If the decision rule is a power priority rule, then when the power margin report is lower than a preset first threshold, or when the uplink channel quality estimate is lower than a preset second threshold, a truncation factor within a first numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission. If the decision rule is a spectrum priority rule, then when the power margin report is higher than a preset third threshold and the uplink channel quality estimate is higher than a preset fourth threshold, a truncation factor within a second numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission. If the decision rule is a bandwidth adaptation rule, then when the number of allocated resource blocks is higher than a preset fifth threshold, a truncation factor within a third numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission, or the truncation factor is reduced based on the determined target truncation factor.

[0009] In one implementation, determining the target truncation factor for the current transmission from a predefined pool of candidate truncation factors based on the decision rule further includes: If the decision rule is a bandwidth adaptation rule, then when the number of allocated resource blocks is lower than the preset sixth threshold, a truncation factor within the fourth numerical range is selected from multiple predefined candidate truncation factors as the target truncation factor used for the current transmission, or a truncation factor is added based on the determined target truncation factor.

[0010] In one implementation, based on a pre-defined joint optimization model, the target truncation factor for the current transmission is determined from a plurality of predefined candidate truncation factors, including: Based on the preset joint optimization model, the joint metric value corresponding to each candidate cutoff factor is calculated, and the candidate factor with the largest joint metric value is taken as the target cutoff factor.

[0011] In one implementation, the joint metric is represented as: Metric(α) = SE(α) × (1 - BLER(SNR_eff(α))) Where α is the candidate truncation factor, SE(α) is the effective spectral efficiency after applying the truncation factor α, SNR_eff(α) is the equivalent received signal-to-noise ratio after considering the transmit power gain or loss due to the reduction in peak-to-average power ratio, and BLER(·) is the block error rate function under a given modulation and coding scheme and equivalent received signal-to-noise ratio; the effective spectral efficiency and transmit power gain are obtained through a pre-stored performance lookup table.

[0012] In one implementation, synchronizing the target truncation factor to the transmitting and receiving devices includes: When the target cutoff factor is determined autonomously by the transmitting device, the receiving device is informed of the target cutoff factor to be used. When the target cutoff factor is determined autonomously or assisted by the receiving device, the receiving device sends a configuration instruction for the target cutoff factor to the transmitting device through downlink control information.

[0013] In one implementation, the target truncation factor is used to perform a discrete Fourier transform and spectral truncation on the modulation symbol to be transmitted, generating and transmitting the final time-domain waveform signal, including: Perform a discrete Fourier transform on the modulation symbol to be transmitted to obtain a frequency domain sequence; Based on the target truncation factor, calculate the actual number of subcarriers mapped, and extract the corresponding samples from the frequency domain sequence based on the number of subcarriers; The captured samples are mapped onto continuous or specified subcarriers, and then processed by inverse fast Fourier transform to generate the final time-domain waveform signal, which is then sent.

[0014] Secondly, embodiments of the present invention also provide an adaptive spectrum truncation apparatus for a single-carrier frequency division multiple access system, wherein the apparatus is used to implement the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system described in any of the above-mentioned schemes, and the apparatus includes: The context acquisition module is used to obtain the context information of the current transmission; The decision module is used to determine the target truncation factor to be used in the current transmission from a plurality of predefined candidate truncation factors based on the context information, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform. The signaling module is used to synchronize the target truncation factor to the transmitting and receiving devices; The signal processing module is used to perform discrete Fourier transform and spectral truncation processing on the modulation symbol to be transmitted using the target truncation factor, and generate and send the final time-domain waveform signal.

[0015] Thirdly, embodiments of the present invention also provide a terminal, wherein the terminal includes a memory, a processor, and an adaptive spectrum truncation program for a single-carrier frequency division multiple access system stored in the memory and executable on the processor. When the processor executes the adaptive spectrum truncation program for a single-carrier frequency division multiple access system, it implements the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system of any of the above schemes.

[0016] Fourthly, embodiments of the present invention also provide a computer-readable storage medium, wherein the computer-readable storage medium stores an adaptive spectrum truncation program for a single-carrier frequency division multiple access system, the adaptive spectrum truncation program for a single-carrier frequency division multiple access system implementing the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system as described in any of the above schemes on the computer-readable storage medium.

[0017] Beneficial Effects: Compared with existing technologies, this invention provides an adaptive spectrum truncation method for single-carrier frequency division multiple access systems. First, the context information of the current transmission is obtained. Then, based on the context information, a target truncation factor is determined from a plurality of predefined candidate truncation factors, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points in the original discrete Fourier transform. Next, the target truncation factor is synchronized to the transmitting and receiving devices, and the target truncation factor is used to perform discrete Fourier transform and spectrum truncation processing on the modulation symbols to be transmitted, generating and transmitting the final time-domain waveform signal.

[0018] This invention focuses on a lightweight adaptive mechanism for frequency domain sample truncation. It determines the target truncation factor through contextual information and achieves dynamic binding between the truncation factor and the instantaneous wireless environment and terminal state without machine learning training or complex signaling interaction. It can make real-time and intelligent trade-offs between power efficiency and spectral efficiency, and is particularly suitable for devices that are sensitive to complexity and latency. Attached Figure Description

[0019] Figure 1 This is a flowchart of a preferred embodiment of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system provided by the present invention.

[0020] Figure 2 The flowchart illustrates the application of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system provided in this embodiment of the invention.

[0021] Figure 3 This is a schematic diagram of the first embodiment of the adaptive spectrum truncation device for a single-carrier frequency division multiple access system provided by the present invention.

[0022] Figure 4 This is a schematic diagram of the second embodiment of the adaptive spectrum truncation device for a single-carrier frequency division multiple access system provided in this invention.

[0023] Figure 5 A schematic diagram of a terminal provided in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0025] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content, operations, or steps, nor does it require execution in the described order. For example, some operations or steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0026] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0027] It should be understood that, in order to clearly describe the technical solutions of the embodiments of the present invention, the terms "first" and "second" are used in the embodiments of the present invention to distinguish identical or similar items with essentially the same function and effect. For example, "first control information" and "second control information" are only used to distinguish different control information and do not limit their order.

[0028] Those skilled in the art will understand that the words "first" and "second" do not limit the quantity or the order of execution, and that the words "first" and "second" do not necessarily imply that they are different.

[0029] It should also be understood that the term “and / or” as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0030] To address the suboptimal performance of existing fixed spectrum truncation strategies, this embodiment provides an adaptive spectrum truncation method for single-carrier frequency division multiple access (FDMA) systems. Fundamentally different from existing static schemes, the core of this embodiment lies in introducing a real-time context-aware adaptive decision-making mechanism. In specific implementation, this embodiment first acquires the current transmission context information. Then, based on this context information, it determines the target truncation factor for the current transmission from a plurality of predefined candidate truncation factors. The target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points in the original Discrete Fourier Transform (DFT). Next, the target truncation factor is synchronized to the transmitting and receiving devices, and the DFT is used to perform DFT and spectrum truncation processing on the modulation symbols to be transmitted, generating and transmitting the final time-domain waveform signal. This embodiment achieves dynamic binding of the truncation factor with the instantaneous wireless environment and terminal state, enabling real-time and intelligent trade-offs between power efficiency and spectral efficiency.

[0031] Unlike existing static solutions, the core of this invention lies in introducing a real-time context-aware adaptive decision-making mechanism. Specifically, the target truncation factor is dynamically determined during each transmission based on real-time acquired or updated context information, including: channel quality indication, precoding matrix indication, modulation and coding scheme level, number of allocated resource blocks, and power margin report. In this way, the invention achieves dynamic binding of the truncation factor to the instantaneous wireless environment and terminal state, enabling real-time and intelligent trade-offs between power efficiency and spectral efficiency.

[0032] The adaptive spectrum truncation method for single-carrier frequency division multiple access systems in this embodiment can be applied to terminals, including intelligent product terminals such as computers. Specifically, as shown in the example... Figure 1 As shown in the figure, the adaptive spectrum truncation method for a single-carrier frequency division multiple access system in this embodiment includes the following steps: Step S100: Obtain the current transmission context information.

[0033] In this embodiment, combined with Figure 2As shown, the context information includes any one or more of the following: channel state information, modulation and coding scheme level, number of allocated resource blocks or bandwidth, and power margin report of user equipment. Specifically, the channel state information reflects the transmission quality of the current wireless channel, and its form is uplink channel quality estimation, precoding matrix indicator (PMI), or channel matrix based on channel reciprocity estimation. Uplink channel quality estimation is the channel quality level calculated by the terminal based on parameters such as the signal-to-noise ratio (SNR) of the received signal; the precoding matrix indicator is used to indicate the precoding matrix recommended by the terminal, indirectly reflecting the spatial characteristics of the channel; the channel matrix based on channel reciprocity estimation can more accurately describe the transmission characteristics of the channel and is suitable for time-division duplex systems. The modulation and coding scheme level is configured by the network device for the terminal according to channel quality and service requirements, and is used to indicate the modulation method and coding rate adopted by the terminal, directly affecting the data transmission rate and reliability. Modulation and coding scheme levels usually correspond to different spectral efficiencies; the higher the level, the higher the spectral efficiency. A resource block (RB) is the basic unit of resource allocation in a NR (5G New Radio) system. The more resource blocks allocated, the wider the transmission bandwidth available to the terminal, and the larger the amount of data it can carry. However, this may also lead to a higher peak-to-average power ratio (PAPR). The number of allocated resource blocks or bandwidth information is sent to the terminal by the network device through scheduling authorization messages. The user equipment's Power Headroom Report (PHR) indicates the terminal's remaining available transmit power, which is the difference between the terminal's maximum available transmit power and its current actual transmit power. A negative PHR value indicates that the terminal's power is limited; the larger the absolute value of the negative value, the more severe the power limitation. A positive PHR value indicates that the terminal has remaining transmit power; the larger the positive value, the more abundant the power.

[0034] In practical applications, this embodiment can acquire context information locally and by receiving information sent from the network. When acquiring information locally, the system receives reference signals and channel state information (CSSI) signals from the network device, measures and calculates channel state information such as uplink channel quality estimation, precoding matrix indication, and channel matrix. It also obtains the current transmit power and maximum available transmit power through its own power detection module, allowing for the calculation of a power margin report. When receiving information sent from the network device, the system receives scheduling grant messages (such as uplink and downlink scheduling grants) from the network device, acquiring information such as modulation and coding scheme level, the number of allocated resource blocks, or bandwidth.

[0035] Step S200: Based on the context information, determine the target truncation factor used in the current transmission from a plurality of predefined candidate truncation factors, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform.

[0036] This embodiment includes two methods for determining the target truncation factor. The first method is: based on the context information, establish a decision rule associated with the context information; based on the decision rule, determine the target truncation factor used for the current transmission from a plurality of predefined candidate truncation factors. The first method corresponds to... Figure 2 Method A is one of the methods. The second method involves determining the target truncation factor for the current transmission from multiple predefined candidate truncation factors based on a pre-defined joint optimization model. This second method corresponds to... Figure 2 Method B in this embodiment, which determines the target stage factor, can be effectively distinguished from the direct reading of fixed values ​​in the prior art.

[0037] Specifically, such as Figure 2 As shown, in this embodiment, Method A (i.e., the first method) determines the decision rule based on context information, and then determines the target cutoff factor based on the preset decision rule. The context information includes channel state information (uplink channel quality estimation), modulation and coding scheme level, the number or bandwidth of allocated resource blocks, and any one or more of the user equipment's power margin report. Therefore, the decision rule in this embodiment is established based on any one or more of the channel state information (uplink channel quality estimation), modulation and coding scheme level, the number or bandwidth of allocated resource blocks, and the user equipment's power margin report. Therefore, combined with... Figure 2 As shown in the illustration, when determining the target truncation factor using method A in this embodiment, the established decision rules are executed based on channel state information (uplink channel quality estimation), modulation and coding scheme level, the number of allocated resource blocks or bandwidth, and the power margin report of user equipment. The core of this approach is to select a truncation strategy based on whether the primary challenge facing current transmission is "power constraint" or "spectrum constraint." The decision rules in this embodiment include: power priority rule, spectrum efficiency priority rule, and bandwidth adaptation rule.

[0038] Specifically, the process of determining the target cutoff factor includes: If the decision rule is a power priority rule, then when the Power Headroom Report (PHR) is lower than a preset first threshold, or the Uplink Channel Quality Estimate (SNR) is lower than a preset second threshold, it indicates that the transmission is limited by power or coverage. In this case, a truncation factor within a first numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission. The target truncation factor determined at this time tends to be a lower value, such as the first numerical range of 10%-20%, in order to maintain a lower peak-to-average power ratio, thereby allowing user terminals to transmit with higher average power and prioritizing link reliability and coverage.

[0039] If the decision rule is a spectrum-priority rule, then when the power margin report is higher than a preset third threshold and the uplink channel quality estimate is higher than a preset fourth threshold, it indicates that the channel conditions are excellent and the terminal power is sufficient. In this case, a truncation factor within a second numerical range is selected from a predefined pool of candidate truncation factors as the target truncation factor for the current transmission. The target truncation factor determined in this case tends to be a higher value, for example, a second numerical range of 30%-40%, sacrificing some average peak-to-weight ratio performance in exchange for higher spectral efficiency to meet the demands of high-throughput services.

[0040] If the decision rule is a bandwidth adaptation rule, then when the number of allocated resource blocks is higher than a preset fifth threshold, due to the inherently high PAPR of broadband signals, a truncation factor within a third numerical range is selected from a predefined pool of candidate truncation factors as the target truncation factor for the current transmission. Alternatively, the truncation factor is reduced based on the already determined target truncation factor, in which case the third numerical range also tends to be smaller to control the total PAPR and ensure power amplifier efficiency. If the number of allocated resource blocks is lower than a preset sixth threshold, then a truncation factor within a fourth numerical range is selected from a predefined pool of candidate truncation factors as the target truncation factor for the current transmission. Alternatively, the truncation factor is increased based on the already determined target truncation factor, in which case the fourth numerical range also tends to be larger to make fuller use of the spectrum. In another implementation, method B (i.e., the second method) determines the target cutoff factor through a joint optimization model. Specifically, combining... Figure 2 As shown, this embodiment calculates a joint metric for each candidate cutoff factor based on a preset joint optimization model, and selects the candidate factor with the largest joint metric as the target cutoff factor. The joint metric is expressed as: Metric(α) = SE(α) × (1 - BLER(SNR_eff(α))) Where α is a candidate truncation factor, SE(α) is the effective spectral efficiency after applying the truncation factor α, SNR_eff(α) is the equivalent received signal-to-noise ratio after considering the transmit power gain or loss due to the reduction in peak-to-average power ratio, and BLER(·) is the block error rate function under a given modulation and coding scheme and equivalent received signal-to-noise ratio; the effective spectral efficiency and transmit power gain are obtained through a pre-stored performance lookup table. In this embodiment, the value of the truncation factor α is positively correlated with the effective spectral efficiency SE(α) and negatively correlated with the transmit power gain ΔP_tx(α) relative to the quadrature phase shift keying waveform; the predefined candidate truncation factors include one or more of 0%, 10%, 20%, 30%, and 40%.

[0041] Method B in this embodiment can be applied to network-assisted adaptive spectrum truncation scenarios, as shown in Table 1. Table 1 is a lookup table of adaptive truncation performance of DFT-s-OFDM (Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing) using π / 2-BPSK modulation, based on typical simulation assumptions (30kHz SCS, TDL-C 300ns channel, PC2 / PC3 UE).

[0042] Table 1

[0043] In this embodiment, PC (Power Class) refers to the power level. A smaller number indicates a higher maximum allowable transmit power. In 5G NR and 6G discussions, PC3 (23dBm) is the most common power level for handheld terminals, while PC2 (26dBm) represents terminals supporting even higher power. It should be noted that this embodiment does not exclude the use of a more refined set of cutoff factor candidates or the MCS table specified in the latest standards; the current table is merely for illustrative purposes.

[0044] Method A in this embodiment can be applied to the autonomous adaptive spectrum truncation scenario on the terminal side, as shown in Table 2. Table 2 is an adaptive decision reference table taking noise-limited scenarios (rural areas, suburbs) as an example.

[0045] Table 2

[0046] In this embodiment, the typical method for obtaining uplink channel quality estimation is to measure the uplink sounding reference signal (SRS) on the network side, or to infer the channel reciprocity based on TDD (Time Division Duplex, a time-division-based bidirectional communication technology).

[0047] Step S300: Synchronize the target cutoff factor to the transmitting and receiving devices.

[0048] In practical applications, after determining the target cutoff factor, this embodiment, as follows: Figure 2 As shown, the target truncation factor is synchronized. Specifically, when the target truncation factor is determined autonomously by the transmitting device, it indicates the target truncation factor to be used to the receiving device. In this case, the indication can be achieved through reserved bits in the uplink control information. When the target truncation factor is determined autonomously or assistedly by the receiving device, the receiving device sends a configuration indication of the target truncation factor to the transmitting device through downlink control information. In this case, the configuration indication can be achieved by reusing existing waveform indication fields or defining new fields. In other implementations, this embodiment can also pre-configure the mapping rule between the target truncation factor and context information parameters through higher-layer signaling when synchronizing the target truncation factor. Both the receiving device and the transmitting device store this mapping rule. During communication, the receiving device and the transmitting device independently determine the target truncation factor by querying the pre-configured mapping rule based on the context information acquired in real time, without the need for additional real-time signaling indication, thus achieving implicit synchronization.

[0049] Step S400: Use the target truncation factor to perform discrete Fourier transform and spectral truncation processing on the modulation symbol to be transmitted, and generate and send the final time-domain waveform signal.

[0050] Furthermore, in this embodiment, a Discrete Fourier Transform (DFT) is performed on the L modulation symbols to be transmitted to obtain a frequency domain sequence S_k. Next, based on the target truncation factor α, the actual number of mapped subcarriers K = L × (1-α) is calculated, and K corresponding samples are truncated from the frequency domain sequence based on the number of subcarriers K (usually selected based on their inherent conjugate symmetry). The truncated K samples are mapped onto K consecutive or specified subcarriers, and then processed by an inverse Fast Fourier Transform to generate the final time-domain waveform signal, which is then transmitted.

[0051] Based on the above embodiments, the present invention also provides an adaptive spectrum truncation device for a single-carrier frequency division multiple access system. The device in this embodiment can be used to implement the steps in the above method embodiments. Specifically, as follows... Figure 3As shown, the apparatus of this embodiment includes: a context acquisition module 10, a decision module 20, a signaling module 30, and a signal processing module 40. Specifically, the context acquisition module 10 is used to acquire the context information of the current transmission. The decision module 20 is used to determine the target truncation factor used in the current transmission from a plurality of predefined candidate truncation factors based on the context information, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform. The signaling module 30 is used to synchronize the target truncation factor to the transmitting device and the receiving device. The signal processing module 40 is used to perform discrete Fourier transform and spectral truncation processing on the modulation symbol to be transmitted using the target truncation factor, generating and transmitting the final time-domain waveform signal.

[0052] Based on the method for determining the target truncation factor in this embodiment, the adaptive spectrum truncation device for a single-carrier frequency division multiple access system in this embodiment can be a device that autonomously implements adaptive spectrum truncation on the terminal side. Taking the user equipment (UE) performing adaptive spectrum truncation as an example, after receiving the uplink scheduling authorization from the base station (gNB) (which includes the modulation and coding scheme MCS, resource block (RB) allocation, etc.), the UE performs the following steps: 1. Obtain context information: (1) Obtain an uplink channel quality estimate (e.g., signal-to-noise ratio SNR = 5dB) based on the measurement feedback or channel reciprocity of the uplink sounding reference signal (SRS).

[0053] (2) Read the local power headroom report (PHR). For example, if the PHR is -3dB, it indicates that the UE is currently in a power-limited state.

[0054] (3) Obtain the number of resource blocks (RBs) authorized for scheduling, for example, 16 RBs.

[0055] 2. Dynamic decision-making target cutoff factor α: According to the preset decision rules (corresponding to method A), the UE makes a judgment: Condition 1: PHR = -3dB < 0dB (first threshold), indicating that the power is severely limited.

[0056] Condition 2: SNR = 5dB is at a moderate level.

[0057] Condition 3: The number of RBs allocated (16) is of medium bandwidth.

[0058] Decision logic: Since the primary challenge is power limitation, according to the power priority rule, the UE should prioritize selecting a smaller cutoff factor α to maintain a lower PAPR, thereby maximizing the available transmit power. Therefore, the UE selects α=0% (or 10%) as the target cutoff factor from the candidate cutoff factors {0%, 10%, 20%, 30%}.

[0059] 3. Signal generation and factor indication: (1) The UE performs standard DFT-s-OFDM processing on the π / 2-BPSK modulation symbols using the selected α=0% (i.e., no truncation) to generate and transmit the uplink signal. This is intended to achieve maximum coverage under the current channel and power conditions.

[0060] (2) At the same time, in order to inform the gNB receiver of the specific waveform parameters used in this transmission, the UE uses two reserved bits (e.g., "00", corresponding to "no truncation" in the predefined codebook) in the uplink control information (UCI) transmitted in this uplink shared channel (PUSCH) to indicate the target truncation factor α used.

[0061] 4. Network-side reception: Based on the received target truncation factor α indication (“00”), the gNB knows that the UE used an untrunculated π / 2-BPSKDFT-s-OFDM waveform, and thus uses the corresponding receiving algorithm (such as equalization using frequency domain integrity symmetry) to correctly decode.

[0062] In another implementation, the adaptive spectrum truncation device for a single-carrier frequency division multiple access system in this embodiment can also be a network-assisted adaptive spectrum truncation device. In this case, the context acquisition module 10, decision module 20, and signaling module 30 are located on the network side, and the signal processing module is located on the terminal side, as detailed below. Figure 4 As shown in the diagram. For example, in a scenario where a base station (gNB) significantly improves uplink transmission efficiency based on π / 2-BPSK under medium channel conditions using the method of this invention, the steps include: 1. Scenario and Scheduling Objectives: The gNB estimates the UE's uplink channel quality to be moderate (e.g., SNR = 4 dB). The goal is to maximize the data rate while ensuring coverage reliability.

[0063] 2. Network-side decision-making (limitations of standard solutions, based on 3GPP 38.214 Table 6.1.4.1-2): Option A (Standard π / 2-BPSK Upper Limit): To ensure reliable coverage, gNB first considers the most robust option, namely using π / 2-BPSK modulation. According to the protocol, the highest MCS it can support under the current channel is MCS 5, corresponding to a spectral efficiency of 0.1934 bps / Hz. This option is very reliable, but the data rate is relatively low.

[0064] Option B (Trying Standard QPSK): To achieve higher data rates, the standard practice is to try switching to QPSK modulation, such as scheduling MCS6 (spectral efficiency 0.2344 bps / Hz). However, with an SNR of 4dB, the bit error rate of QPSK may already be close to the acceptable threshold, posing a stability risk.

[0065] In other implementations, if the present invention is based on network-side assisted adaptive spectrum truncation, further optimizations can be made. When applying the adaptive spectrum truncation method of the present invention to a gNB, an enhancement scheme is evaluated: Option C (Invention: π / 2-BPSK MCS 5 + Truncation): Schedule π / 2-BPSK (MCS 5, base spectral efficiency 0.1934), but simultaneously instruct the application of a truncation factor α=20%.

[0066] Calculate the equivalent spectral effect: 0.1934×1 / (1 0.2)=0.1934×1.25=0.24175 bps / Hz Performance Analysis: This scheme maintains the inherent high reliability of π / 2-BPSK modulation while increasing the equivalent spectral efficiency from 0.1934 bps / Hz to approximately 0.242 bps / Hz through truncation. This value surpasses that of the standard QPSK scheme B (MCS 6, 0.2344 bps / Hz).

[0067] Joint optimization decision-making: gNB, through model calculations, found that under the current channel conditions: The metric value of scheme C (π / 2-BPSK, α=20%) is significantly higher than that of scheme A (π / 2-BPSK, α=0%) because it brings a significant (~25%) rate improvement with minimal loss of reliability.

[0068] Scheme C also has a higher metric value than Scheme B (QPSK, MCS 6) because it achieves higher spectral efficiency (0.242>0.234) while retaining the better anti-interference capability of π / 2-BPSK.

[0069] Therefore, gNB decides to adopt option C, which is to choose MCS 5. It also indicates that α = 20%.

[0070] 4. Network Instructions and UE Execution: The gNB schedules this transmission via DCI. The "MCS" field indicates 5, and the extended field indicates α=20%. Based on this, the UE performs spectral truncation of α=20% on the π / 2-BPSK symbol corresponding to MCS 5 and transmits it. For example, in DCI format 0_2, the gNB uses the extended "Waveform and Truncation Indication" field (e.g., 3 bits) to indicate "CP-OFDM", "DFT-s-OFDM without truncation", "DFT-s-OFDM α=10%"... "DFT-s-OFDM α=40%", specifically "DFT-s-OFDM α=20%", which is "011".

[0071] As can be seen from the above embodiments, the present invention can effectively improve the overall performance of the 6G uplink by introducing an adaptive truncation factor selection mechanism to intelligently balance power efficiency and spectral efficiency.

[0072] The adaptive spectrum truncation device for a single-carrier frequency division multiple access system in this embodiment is based on the same principle as the steps in the above method embodiments, and will not be described in detail here.

[0073] In summary, compared with the prior art, the present invention has the following significant advantages: (1) Optimal performance: By dynamically binding the truncation factor with the real-time channel state, UE capability and scheduling parameters, the limitations of fixed truncation are broken, and the system can automatically optimize in different scenarios to maximize system throughput or energy efficiency.

[0074] (2) Strong adaptability: The solution is compatible with both power-constrained coverage scenarios and high-speed scenarios that prioritize spectrum efficiency, achieving global optimization of network performance.

[0075] (3) Low implementation complexity: The core decision-making process can be completed using a simple lookup table or a lightweight rule engine, which greatly increases the requirements for the UE's baseband processing capabilities.

[0076] (4) Good standard compatibility: It does not change the basic waveform framework of DFT-s-OFDM, but only serves as an enhancement processing strategy on its upper layer. It is easy to integrate into the existing communication standard system and has strong backward compatibility.

[0077] Based on the above embodiments, the present invention also provides a terminal, the principle block diagram of which can be as follows: Figure 5 As shown. The terminal may include one or more processors 100 ( Figure 5(Only one is shown in the image), memory 101, and computer program 102 stored in memory 101 and executable on one or more processors 100. For example, an adaptive spectrum truncation program for a single-carrier frequency division multiple access system. When one or more processors 100 execute computer program 102, they can implement the various steps in the adaptive spectrum truncation method embodiment for a single-carrier frequency division multiple access system. Alternatively, when one or more processors 100 execute computer program 102, they can implement the functions of various modules / units in the adaptive spectrum truncation system embodiment for a single-carrier frequency division multiple access system, without limitation herein.

[0078] In one embodiment, the processor 100 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0079] In one embodiment, memory 101 may be an internal storage unit of an electronic device, such as a hard drive or RAM. Memory 101 may also be an external storage device of the electronic device, such as a plug-in hard drive, Smart Media Card (SMC), Secure Digital Card (SD), or Flash Card. Furthermore, memory 101 may include both internal and external storage units. Memory 101 is used to store computer programs and other programs and data required by the terminal. Memory 101 can also be used to temporarily store data that has been output or will be output.

[0080] Those skilled in the art will understand that Figure 5 The block diagram shown is merely a partial structural diagram related to the present invention and does not constitute a limitation on the terminal to which the present invention is applied. A specific terminal may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0081] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided by this invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), direct memory bus RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An adaptive spectrum truncation method for a single-carrier frequency division multiple access system, characterized in that, The method includes: Obtain the context information of the current transmission; Based on the context information, the target truncation factor used in the current transmission is determined from a plurality of predefined candidate truncation factors, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform. Synchronize the target cutoff factor to the transmitting and receiving devices; The target truncation factor is used to perform discrete Fourier transform and spectral truncation on the modulation symbol to be transmitted, generating and sending the final time-domain waveform signal.

2. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 1, characterized in that, The context information includes any one or more of the following: channel state information, modulation and coding scheme level, number of allocated resource blocks or bandwidth, and power margin report of user equipment; wherein, the channel state information is in the form of uplink channel quality estimation, precoding matrix indication, or channel matrix based on channel reciprocity estimation.

3. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 2, characterized in that, Based on the context information, the target truncation factor for the current transmission is determined from a plurality of predefined candidate truncation factors, including: Based on the context information, a decision rule associated with the context information is established. Based on the decision rule, the target truncation factor to be used in the current transmission is determined from a plurality of predefined candidate truncation factors. or, Based on a pre-defined joint optimization model, the target truncation factor for the current transmission is determined from multiple predefined candidate truncation factors.

4. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 3, characterized in that, The decision rules include: power priority rule, spectrum priority rule, and bandwidth adaptation rule; based on the decision rules, the target truncation factor to be used for the current transmission is determined from a plurality of predefined candidate truncation factors, including: If the decision rule is a power priority rule, then when the power margin report is lower than a preset first threshold, or when the uplink channel quality estimate is lower than a preset second threshold, a truncation factor within a first numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission. If the decision rule is a spectrum priority rule, then when the power margin report is higher than a preset third threshold and the uplink channel quality estimate is higher than a preset fourth threshold, a truncation factor within a second numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission. If the decision rule is a bandwidth adaptation rule, then when the number of allocated resource blocks is higher than a preset fifth threshold, a truncation factor within a third numerical range is selected from a plurality of predefined candidate truncation factors as the target truncation factor used for the current transmission, or the truncation factor is reduced based on the determined target truncation factor.

5. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 4, characterized in that, Based on the decision rule, determining the target truncation factor for the current transmission from a predefined pool of candidate truncation factors further includes: If the decision rule is a bandwidth adaptation rule, then when the number of allocated resource blocks is lower than the preset sixth threshold, a truncation factor within the fourth numerical range is selected from multiple predefined candidate truncation factors as the target truncation factor used for the current transmission, or a truncation factor is added based on the determined target truncation factor.

6. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 3, characterized in that, Based on a pre-defined joint optimization model, the target truncation factor for the current transmission is determined from a plurality of predefined candidate truncation factors, including: Based on the preset joint optimization model, the joint metric value corresponding to each candidate cutoff factor is calculated, and the candidate factor with the largest joint metric value is taken as the target cutoff factor.

7. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 6, characterized in that, The joint metric value is expressed as: Metric(α) = SE(α) × (1 - BLER(SNR_eff(α))) Where α is the candidate truncation factor, SE(α) is the effective spectral efficiency after applying the truncation factor α, SNR_eff(α) is the equivalent received signal-to-noise ratio after considering the transmit power gain or loss due to the reduction in peak-to-average power ratio, and BLER(·) is the block error rate function under a given modulation and coding scheme and equivalent received signal-to-noise ratio; the effective spectral efficiency and transmit power gain are obtained through a pre-stored performance lookup table.

8. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 1, characterized in that, Synchronizing the target cutoff factor to the transmitting and receiving devices includes: When the target cutoff factor is determined autonomously by the transmitting device, the receiving device is informed of the target cutoff factor to be used. When the target cutoff factor is determined autonomously or assisted by the receiving device, the receiving device sends a configuration instruction for the target cutoff factor to the transmitting device through downlink control information.

9. The adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to claim 1, characterized in that, The target truncation factor is used to perform Discrete Fourier Transform and spectral truncation on the modulation symbol to be transmitted, generating and transmitting the final time-domain waveform signal, including: Perform a discrete Fourier transform on the modulation symbol to be transmitted to obtain a frequency domain sequence; Based on the target truncation factor, calculate the actual number of subcarriers mapped, and extract the corresponding samples from the frequency domain sequence based on the number of subcarriers; The captured samples are mapped onto continuous or specified subcarriers, and then processed by inverse fast Fourier transform to generate the final time-domain waveform signal, which is then sent.

10. An adaptive spectrum truncation device for a single-carrier frequency division multiple access system, characterized in that, The apparatus is used to implement the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system according to any one of claims 1-10, the apparatus comprising: The context acquisition module is used to obtain the context information of the current transmission; The decision module is used to determine the target truncation factor to be used in the current transmission from a plurality of predefined candidate truncation factors based on the context information, wherein the target truncation factor is the ratio of the number of target frequency domain samples to be truncated to the number of points of the original discrete Fourier transform. The signaling module is used to synchronize the target truncation factor to the transmitting and receiving devices; The signal processing module is used to perform discrete Fourier transform and spectral truncation processing on the modulation symbol to be transmitted using the target truncation factor, and generate and send the final time-domain waveform signal.

11. A terminal, characterized in that, The terminal includes a memory, a processor, and an adaptive spectrum truncation program for a single-carrier frequency division multiple access system stored in the memory and executable on the processor. When the processor executes the adaptive spectrum truncation program for a single-carrier frequency division multiple access system, it implements the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system as described in any one of claims 1-9.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores an adaptive spectrum truncation program for a single-carrier frequency division multiple access system, the adaptive spectrum truncation program for a single-carrier frequency division multiple access system implementing the steps of the adaptive spectrum truncation method for a single-carrier frequency division multiple access system as described in any one of claims 1-9 on the computer-readable storage medium.

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