Schemes for flexible CP configuration
Patent Information
- Application Number
- PCT/CN2025/082161
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-09-17
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Figure CN2025082161_17092026_PF_FP_ABST
Abstract
Description
SCHEMES FOR FLEXIBLE CP CONFIGURATIONFIELD
[0001] This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus about procedures for schemes for flexible CP configuration related issues.BACKGROUND
[0002] In communication systems, there can be latency deviations, especially in scenarios such as deep coverage and Non-Terrestrial Networks (NTN) , where signal transmission latency deviations can be significant. In these systems, RAN4 typically defines requirements for latency deviations, generally ensuring that they do not exceed CP / 2 (Cyclic Prefix / 2) to maintain the accuracy, reliability, and success rate of communication transmissions.
[0003] To address scenarios with significant latency deviations, this proposal introduces the configuration of a flexible Cyclic Prefix (CP) . By implementing a flexible CP configuration, the accuracy, reliability, and success rate of communication transmissions can be enhanced in scenarios with substantial latency deviations.SUMMARY
[0004] In communication systems, there can be delay variations. In scenarios like deep coverage and NTN, these delay variations can be significant. RAN4 typically defines requirements for delay variations, usually not exceeding CP / 2, to ensure communication accuracy, reliability, and success rate. This proposal suggests a flexible CP configuration to improve accuracy, reliability, and success rate in scenarios with significant delay variations.
[0005] In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE. The UE receives flexible CP configuration. The UE determines the CP configuration based on the flexible CP configuration.
[0006] To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 is a diagram illustrating an example of the distributed CP.
[0008] Figure 2 is a diagram illustrating an example of the aggregated CP.
[0009] Figure 3 is a diagram illustrating an example of the aggregated CP.
[0010] Figure 4 is a diagram illustrating an example of the aggregated CP with repetition.DETAILED DESCRIPTION
[0011] The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.
[0012] Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.
[0013] In communication systems, there can be latency deviations, especially in scenarios such as deep coverage and Non-Terrestrial Networks (NTN) , where signal transmission latency deviations can be significant. In these systems, RAN4 typically defines requirements for latency deviations, generally ensuring that they do not exceed CP / 2 (Cyclic Prefix / 2) . This is done to maintain the accuracy, reliability, and success rate of communication transmissions.
[0014] In this context, a flexible CP configuration is proposed to address scenarios with significant latency deviations. By implementing a flexible CP, the communication system can better accommodate larger latency deviations, thereby enhancing the accuracy, reliability, and success rate of signal transmissions in such challenging environments. This approach ensures that even in the presence of substantial latency deviations, the communication system can maintain high performance and robustness.
[0015] This invention is motivated by, but not limited to, an NTN scenario. In such a scenario, introducing innovative approaches on following aspects to boost the process's efficiency for user equipment's initial network access: · Flexible CP procedure · resource allocation of PDCCH / PUCCH / PDSCH / PUSCH · Flexible CP configuration · maximum CP length for aggregated CP configuration · repetition configuration of the flexible CP More specifically, we propose to consider the following proposals:Proposal#1: Flexible CP procedure For flexible CP procedure, at least two opinions can be involved: distributed CP and aggregated CP. Assume the length of the signal is X symbols, the flexible CP configuration and the aggregated CP option is enabled, then the CP length of the signal transmission should be sum of CP for each of X symbols. Option 1: distributed CP For one transmission of PDCCH / PUCCH / PDSCH / PUSCH or other channels that can be utilized to transmit DL / UL signals or reference signals, the CP is distributed in each symbol of the transmission, as depicted in Fig. 1. Option 2: aggregated CP For one transmission of PDCCH / PUCCH / PDSCH / PUSCH or other channels that can be utilized to transmit DL / UL signals or reference signals, the CP is aggregated in the start parts of the transmission, as depicted in Fig. 2.Proposal#2: resource allocation of PDCCH / PUCCH / PDSCH / PUSCH The Network configures PDCCH / PUCCH / PDSCH / PUSCH with at least one of the following: · Frequency hopping flag (1 / 2bit) : If the value of the frequency hopping flag is 0 / 00, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH without frequency hopping; otherwise, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with frequency hopping. If the value of the frequency hopping flag is 01, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with intra-repetition frequency hopping, if the value of the frequency hopping flag is 10, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with inter-repetition frequency hopping, if the value of the frequency hopping flag is 11, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with intra-repetition and inter-repetition frequency hopping. · PDCCH / PUCCH / PDSCH / PUSCH time resource allocation (2 / 3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the start position (symbol / slot / subframe) and / or length (symbol) of PDCCH / PUCCH / PDSCH / PUSCH in the time domain. The starting position S relative to the start position of PDCCH / PUCCH / PDSCH / PUSCH within one slot or subframe or the offset to one reference point, where the reference point can be the end / start of SSB or particular SIB or RRC or MAC CE or DCI or PDSCH or PUCCH, and where the offset can be symbol offset, or slot offset or subframe offset. The number of consecutive symbols L counting from the starting position S, where the minimum value of L is 1 symbol and the maximum value of L is Lmax. The Lmax can be predefined 4 / 6 / 8 / 10 / 12 / 14 / 28 symbols, where different predefined values can be applied for different channels from PDCCH / PUCCH / PDSCH / PUSCH, or Lmax can be configured via SIB or RRC or MAC CE. Note: · The recourse allocation method above can be applied in not only PDCCH / PUCCH / PDSCH / PUSCH, but also other channels that can be utilized to transmit DL / UL signals or reference signals. · The recourse allocation can be configured with MIB / SIB / RRC / MAC CE / DCI for serving cell / satellite / beam and target cell / satellite / beam. · The PDCCH / PUCCH / PDSCH / PUSCH configuration with SIB can be utilized for initial access and in connected state when there is not dedicated PDCCH / PUCCH / PDSCH / PUSCH configuration with dedicated RRC signalling.Proposal#3: Flexible CP configuration The Network configures Flexible CP configuration with at least one of the following: · Enable or disable of Flexible CP flag (1bit) : If the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled ; otherwise, the Flexible CP procedure is disabled . · Distributed CP and aggregated CP configuration Indication (1bit) : If the value of the Distributed CP and aggregated CP configuration Indication is 0, the Distributed CP of Flexible CP procedure is enabled ; otherwise, the aggregated CP of Flexible CP procedure is enabled . Note: · Enable or disable of Flexible CP flag can be configured with MIB / SIB / RRC / MAC CE / DCI. The indication of Enable or disable of Flexible CP flag can be explicit indication or implicit indication. For implicit indication of Enable or disable of Flexible CP flag , it can be implicit indicated by · repetition number for the transmission of PDCCH / PUCCH / PDSCH / PUSCH or other channels that can be utilized to transmit DL / UL signals or reference signals; when the repetition number is above or not smaller than R_thr, it implicit indicates the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled. R_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · the type of the configurated transmission, for contention-based PUSCH / contention-based transmission except of PRACH, it implicit indicates the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled; for contention-free transmission, it implicit indicates the value of the Enable or disable of Flexible CP flag is 1, the Flexible CP procedure is disabled. · the CP length of latest PRACH configuration, when the CP length of latest PRACH configuration is above or not smaller than L_thr, it implicit indicates the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled. L_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · Retransmission indication or retransmission time, when the transmission is Retransmission or when the transmission time is above not smaller than Re_thr, it implicit indicates the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled. Re_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · Distributed CP and aggregated CP configuration Indication can be configured with MIB / SIB / RRC / MAC CE / DCI. The Distributed CP and aggregated CP configuration Indication can be explicit indication or implicit indication. For implicit indication of Distributed CP and aggregated CP configuration Indication, it can be implicit indicated by · repetition number for the transmission of PDCCH / PUCCH / PDSCH / PUSCH or other channels that can be utilized to transmit DL / UL signals or reference signals; when the repetition number is above or not smaller than R_thr, it implicit indicates the the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled. R_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · the type of the configurated transmission, for contention-based PUSCH / contention-based transmission except of PRACH, it implicit indicates the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled; for contention-free transmission, it implicit indicates the value of the Enable or disable of Flexible CP flag is 0, the Distributed CP of Flexible CP procedure is enabled. · the CP length of latest PRACH configuration, when the CP length of latest PRACH configuration is above or not smaller than L_thr, it implicit indicates the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled. L_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · Retransmission indication or retransmission time, when the transmission is Retransmission or when the transmission time is above not smaller than Re_thr, it implicit indicates the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled. Re_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. · For contention-based PUSCH / contention-based transmission except of PRACH, when flexible CP configuration is enable and Distributed CP and aggregated CP configuration is not configured by network, the aggregated CP configuration is default. Distributed CP and aggregated CP configuration can be additionally configured for contention-based PUSCH / contention-based transmission when flexible CP configuration is enable by network.Proposal#4: maximum CP length for aggregated CP configuration · For one transmission, there can be one or more sets for aggregated CP configuration within one repetition for the transmission. · The sum CP length value for aggregated CP configuration for one set can have maximum value, when above the maximum value, there will be several aggregated CP sets within the signal. · The maximum value of sum CP length value for aggregated CP configuration for one set can be configured with RRC / SIB / MAC CE / DCI or predefined by network, the predefined value can be 2048 / 4096 as the maximum value of sum CP length value for aggregated CP configuration for one set. For example, when the transmission is configured with length L = 20 symbols, the predefined value is 2048 as the maximum value sum CP length value for aggregated CP configuration for one set, then there will be two aggregated CP sets of the transmission is depicted in Fig. 3.Proposal#5: repetition configuration of the flexible CP · For one transmission, there can be one or more repetitions, the repetition value can be configured by RRC / SIB / MIB / DCI. · For the flexible CP configuration when repetition is configured for the transmission, one or more of the following can be applied: · The Enable or disable of Flexible CP flag (1bit) and the Distributed CP and aggregated CP configuration Indication (1bit) in proposal #3 is valid and applied for all repetitions. All repetitions for the transmission have same flexible CP configuration. · The Enable or disable of Flexible CP flag for repetition and the Distributed CP and aggregated CP configuration Indication for repetition can be additionally configured with MIB / SIB / RRC / MAC CE / DCI when repetition is configured for the transmission. All repetitions for the transmission have same flexible CP configuration. · when the repetition number is above or not smaller than R_thr, it implicit indicates the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled. R_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. All repetitions for the transmission have same flexible CP configuration. · when the repetition number is above or not smaller than R_thr, it implicit indicates the the value of the Distributed CP and aggregated CP configuration Indication is 1, the aggregated CP of Flexible CP procedure is enabled. R_thr can be predefined values for different channels or can be configured by network with MIB / SIB / RRC / MAC CE / DCI. All repetitions for the transmission have same flexible CP configuration. For example, when the transmission is configured with repetitions and aggregated CP is configured, then the transmission is depicted in Fig. 4.
[0016] The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”
Claims
1.A method comprising a flexible CP configuration to improve accuracy, reliability, and success rate in scenarios with significant delay variations.2.The method of Claim 1, wherein for flexible CP procedure, at least two opinions can be involved: distributed CP and aggregated CP.3.The method of Claim 2, wherein for one transmission of distributed CP, the CP is distributed in each symbol of the transmission.4.The method of Claim 2, wherein for one transmission of aggregated CP, the CP is the CP is aggregated in the start parts of the transmission.5.The method of Claim 1, wherein the Network configures Flexible CP configuration with at least one of the following:·enable or disable of Flexible CP flag (1bit) : if the value of the Enable or disable of Flexible CP flag is 0, the Flexible CP procedure is enabled; otherwise, the Flexible CP procedure is disabled;·distributed CP and aggregated CP configuration Indication (1bit) : if the value of the Distributed CP and aggregated CP configuration Indication is 0, the Distributed CP of Flexible CP procedure is enabled; otherwise, the aggregated CP of Flexible CP procedure is enabled.6.The method of Claim 1, wherein Flexible CP configuration can be configured with MIB / SIB / RRC / MAC CE / DCI.7.The method of Claim 1, wherein Flexible CP configuration can be explicit indication or implicit indication.8.The method of Claim 7, wherein for implicit indication of, it can be implicit indicated by·repetition number for the transmission·the type of the configurated transmission, for contention-based PUSCH / contention-based transmission except of PRACH or for contention-free transmission·the CP length of latest PRACH configuration·retransmission indication or retransmission time.9.The method of Claim 1, wherein for one transmission, there can be one or more sets for aggregated CP configuration within one repetition for the transmission.10.The method of Claim 1, wherein for the flexible CP configuration when repetition is configured for the transmission, all repetitions for the transmission have same flexible CP configuration.11.A method comprising resource allocation of PDCCH / PUCCH / PDSCH / PUSCH with at least one of the following:·frequency hopping flag (1 / 2bit) : if the value of the frequency hopping flag is 0 / 00, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH without frequency hopping; otherwise, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with frequency hopping, if the value of the frequency hopping flag is 01, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with intra-repetition frequency hopping, if the value of the frequency hopping flag is 10, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with inter-repetition frequency hopping, if the value of the frequency hopping flag is 11, the UE transmits the PDCCH / PUCCH / PDSCH / PUSCH with intra-repetition and inter-repetition frequency hopping,·PDCCH / PUCCH / PDSCH / PUSCH time resource allocation (2 / 3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the start position (symbol / slot / subframe) and / or length (symbol) of PDCCH / PUCCH / PDSCH / PUSCH in the time domain, the starting position S relative to the start position of PDCCH / PUCCH / PDSCH / PUSCH within one slot or subframe or the offset to one reference point, where the reference point can be the end / start of SSB or particular SIB or RRC or MAC CE or DCI or PDSCH or PUCCH, and where the offset can be symbol offset, or slot offset or subframe offset; the number of consecutive symbols L counting from the starting position S, where the minimum value of L is 1 symbol and the maximum value of L is Lmax, the Lmax can be predefined 4 / 6 / 8 / 10 / 12 / 14 / 28 symbols, where different predefined values can be applied for different channels from PDCCH / PUCCH / PDSCH / PUSCH, or Lmax can be configured via SIB or RRC or MAC CE.