Terminal

Abstract

To provide a terminal that can set an appropriate cyclic prefix (CP) according to the compression rate in the time domain using Faster-Than-Nyquist (FTN) or the like.SOLUTION: A terminal transmits and receives slots consisting of multiple symbols. The terminal sets the length of the cyclic prefix added to the symbol on the basis of the degree of compression of the symbol in the time domain.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to terminals that perform wireless communications, and in particular to terminals that support time-domain compression, such as Faster-Than-Nyquist (FTN) transmission. [Background technology]

[0002] The 3rd Generation Partnership Project (3GPP) has developed specifications for the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.

[0003] The 3GPP Release 15 (NR) specifications stipulate that a radio frame (10 ms) is made up of multiple subframes (1 ms), and that a slot is made up of 14 symbols (Non-Patent Document 1).

[0004] In addition, the current NR specification is based on the Nyquist rate and does not support Faster-Than-Nyquist (FTN) transmission. FTN can improve spectral efficiency (SE) compared to Nyquist rate transmission by multiplexing symbols at a rate faster than the Nyquist rate (Non-Patent Document 2).

[0005] Specifically, FTN improves frequency utilization efficiency by allowing inter-symbol interference (ISI) and inter-subcarrier interference (ICI) and by densely multiplexing symbols and / or subcarriers.

[0006] Additionally, studies are underway on NR, which supports frequencies above 52.6 GHz and up to 71 GHz (Non-Patent Document 3). Furthermore, Beyond 5G, 5G Evolution, or 6G (Release-18 and later) aims to support frequency bands above 71 GHz. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] 3GPP TS 38.211 V15.8.0, 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical channels and modulation(Release 15), 3GPP, December 2019 [Non-patent document 2] H. Lin, N. Lahbabi, P. Siohan and X. Jiang, "An efficient FTN implementation of the OFDM / OQAM system", 2015 IEEE International Conference on Communications (ICC), London, 2015, pp. 4787-4792 [Non-patent document 3] "New WID on Extending current NR operation to 71 GHz", RP-193229, 3GPP TSG RAN Meeting #86, 3GPP, December 2019 Summary of the Invention

[0008] When using high frequency bands such as those above 52.6 GHz, increased phase noise and propagation loss become problems, and the system becomes more sensitive to peak-to-average power ratio (PAPR) and power amplifier nonlinearity.

[0009] Considering these issues, it is possible to combine FTN in the time domain with Discrete Fourier Transform-Spread Orthogonal Frequency Division Multiplexing (DFT-s-OFDM), which can improve both spectral efficiency and PAPR.

[0010] However, considering that the time-domain compression rate (which may also be called the compression factor) of FTN is variable, the relationship between the compression rate and the length of the cyclic prefix (CP) added to the OFDM symbol may not always be appropriate.

[0011] Therefore, the following disclosure has been made in consideration of this situation, and aims to provide a terminal that can set an appropriate cyclic prefix (CP) according to the compression rate in the time domain using Faster-Than-Nyquist (FTN) or the like.

[0012] One aspect of the present disclosure is a terminal (UE200) that includes a transceiver unit (FTN modulation module and FTN demodulation module) that transmits and receives slots consisting of multiple symbols, and a control unit that sets the length of a cyclic prefix to be added to the symbols based on the degree of compression of the symbols in the time domain.

[0013] One aspect of the present disclosure is a terminal (UE200) that includes a transceiver unit (FTN modulation module and FTN demodulation module) that transmits and receives slots consisting of multiple symbols, and a control unit that sets compression coefficients to be applied to the time domain of the symbols, and the control unit sets the compression coefficients associated with each of multiple different indicators. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing the overall schematic configuration of a wireless communication system 10. As shown in FIG. [Figure 2]FIG. 2 is a diagram showing the change in the time domain when FTN and DFT-s-OFDM are combined. [Figure 3] FIG. 3 is a diagram showing an example of the configuration of a CP and OFDM symbols before and after FTN modulation (compression) in the time domain. [Figure 4] Figure 4 is a schematic functional block diagram of gNB100 and UE200. [Figure 5] FIG. 5 is a diagram showing an example of a normal CP and OFDM symbol configuration in which FTN is not applied to the time domain. [Figure 6] FIG. 6 is a diagram showing an example of the basic configuration of a CP and an OFDM symbol according to operation example 1-1. [Figure 7] FIG. 7 is a diagram showing a configuration example (α=1, option 1) of the CP and OFDM symbols according to the operation example 1-1. [Figure 8] FIG. 8 is a diagram showing a configuration example (α=1, option 2) of the CP and OFDM symbols according to the operation example 1-1. [Figure 9] FIG. 9 is a diagram showing a configuration example (α=0.8) of the CP and OFDM symbols according to the operation example 1-1. [Figure 10] FIG. 10 is a diagram showing a configuration example (α=0.5) of the CP and OFDM symbols according to the operation example 1-1. [Figure 11A] FIG. 11A is a diagram showing a configuration example (part 1, α=1) of a CP and an OFDM symbol according to operation example 1-2-2. [Figure 11B] FIG. 11B is a diagram showing a configuration example (part 1, α=0.8) of the CP and OFDM symbols according to operation example 1-2-2. [Figure 11C] FIG. 11C is a diagram showing a configuration example (part 1, α=0.5) of a CP and an OFDM symbol according to operation example 1-2-2. [Figure 12A] FIG. 12A is a diagram showing a configuration example (part 2, α=1) of a CP and an OFDM symbol according to operation example 1-2-2. [Figure 12B]FIG. 12B is a diagram showing a configuration example (part 2, α=0.8) of the CP and OFDM symbols according to operation example 1-2-2. [Figure 12C] FIG. 12C is a diagram showing a configuration example (part 2, α=0.5) of the CP and OFDM symbols according to operation example 1-2-2. [Figure 13] FIG. 13 is a diagram showing an example of a combination of a target index, an MCS, and a compression coefficient (α) according to the second operation example. [Figure 14] FIG. 14 is a diagram showing an example (MCS 0) of a table of compression coefficients (α) according to Operation Example 2-1. [Figure 15] FIG. 15 is a diagram showing an example (MCS 10) of a table of compression coefficients (α) according to Operation Example 2-1. [Figure 16] FIG. 16 is a diagram showing an example of a table (MCS 28) of compression coefficients (α) according to the operation example 2-1. [Figure 17] FIG. 17 is a diagram showing an example of a table of compression coefficients (α) according to Operation Example 2-2 (ensuring losslessness). [Figure 18] FIG. 18 is a diagram showing an example of a table of compression coefficients (α) (PAPR optimization) according to operation example 2-2. [Figure 19] FIG. 19 is a diagram showing an example of a table of compression coefficients (α) according to operation example 2-2 (throughput optimization). [Figure 20] FIG. 20 is a diagram illustrating an example of a hardware configuration of the UE 200. As shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0016] (1) Overall configuration of the wireless communication system 1 is a diagram showing an overall schematic configuration of a wireless communication system 10 according to this embodiment. The wireless communication system 10 is a wireless communication system conforming to 5G New Radio (NR), and includes a Next Generation-Radio Access Network 20 (hereinafter, NG-RAN 20) and a terminal 200 (hereinafter, UE 200, User Equipment).

[0017] The NG-RAN 20 includes a radio base station 100 (hereinafter, gNB 100). Note that the specific configuration of the radio communication system 10, including the number of gNBs and UEs, is not limited to the example shown in FIG.

[0018] The NG-RAN 20 actually includes multiple NG-RAN nodes, specifically, gNBs (or ng-eNBs), and is connected to a 5G-compliant core network (5GC, not shown). The NG-RAN 20 and the 5GC may also be simply referred to as a "network."

[0019] The gNB 100 is a radio base station conforming to 5G, and performs 5G radio communication with the UE 200. The gNB 100 and the UE 200 are capable of supporting Massive MIMO (Multiple-Input Multiple-Output), which generates more directional beams by controlling radio signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which aggregates and uses multiple component carriers (CCs), and Dual Connectivity (DC), which simultaneously communicates between the UE and each of two NG-RAN nodes. The wireless communication system 10 supports FR1 and FR2. The frequency bands of each FR are as follows:

[0020] FR1: 410 MHz to 7.125 GHz FR2: 24.25 GHz~52.6 GHz FR1 may use a Sub-Carrier Spacing (SCS) of 15, 30, or 60 kHz and a bandwidth (BW) of 5 to 100 MHz. FR2 is a higher frequency than FR1, and may use an SCS of 60 or 120 kHz (including 240 kHz) and a bandwidth (BW) of 50 to 400 MHz.

[0021] Note that SCS may be interpreted as numerology, which is defined in 3GPP TS38.300 and corresponds to one subcarrier spacing in the frequency domain.

[0022] Furthermore, the wireless communication system 10 may also support a frequency band higher than the FR2 frequency band. Specifically, the wireless communication system 10 may support a frequency band exceeding 52.6 GHz up to 114.25 GHz.

[0023] The high frequency band may be further divided, for example, into a frequency range below 71 GHz and a frequency range above 71 GHz.

[0024] Particularly at these higher frequencies, increased phase noise between carriers becomes a problem, which may necessitate the application of larger (wider) SCS or single-carrier waveforms.

[0025] Also, narrower beams (i.e., more beams) may be required due to increased propagation loss, and greater sensitivity to PAPR and power amplifier nonlinearities may require larger (wider) SCS (and / or fewer FFT points), PAPR reduction mechanisms, or single-carrier waveforms.

[0026] To solve this problem, in this embodiment, a larger SCS (e.g., 480 kHz, 960 kHz) may be used, especially when using a band above 52.6 GHz. Furthermore, Discrete Fourier Transform - Spread Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) may be more widely applied.

[0027] The wireless communication system 10 can also support Faster-Than-Nyquist (FTN) transmission, which can improve frequency utilization efficiency compared to Nyquist rate transmission by multiplexing symbols (specifically, OFDM symbols, abbreviated as symbols where appropriate) at a rate faster than the Nyquist rate.

[0028] FTN may be applied to either the uplink (UL) or the downlink (DL), but does not exclude FTN to both the UL and DL.

[0029] FTN can improve spectral efficiency by allowing inter-symbol interference (ISI) and inter-subcarrier interference (ICI) and multiplexing OFDM symbols at high density. Note that spectral efficiency may be simply called utilization efficiency or may also be called spectral efficiency (SE).

[0030] FIG. 2 shows the time domain changes when combining FTN and DFT-s-OFDM.

[0031] The non-orthogonal subcarriers can be expressed as follows:

[0032] Sub-Carrier Spacing (SCS) (Δf) × OFDM symbol (T) = α < 1 s Here, α is called the FTN modulation coefficient or compression coefficient. The compression coefficient may refer to the compression rate in the time domain by FTN, or may simply be called the compression rate. Furthermore, the compression coefficient does not necessarily refer to the compression rate in the time domain by FTN, and may be a coefficient related to a method other than FTN.

[0033] The waveforms of the non-orthogonal subcarriers described above may be called non-orthogonal waveforms (NOW).

[0034] As shown in Figure 2, comparing the time domain before and after FTN modulation, the symbol length of the OFDM symbol after FTN modulation is scaled by the FTN modulation coefficient α. Due to this characteristic, α may also be called the squeezing factor.

[0035] Specifically, the symbol length is shorter than before FTN modulation, that is, the OFDM symbol is compressed in the time domain compared to before FTN modulation. The degree of compression can be controlled by α.

[0036] The time domain may be referred to as the time direction, and the symbol length may be referred to as the time length of the symbol, the symbol length, the symbol period, or the symbol time.

[0037] In this way, FTN is applied in the time domain (FTN modulation), and the non-orthogonal waveform (NOW) may be expressed as follows:

[0038] DFT-s-OFDM + FTN in the time domain In this case, the length of the cyclic prefix (CP) is preferably set based on the compression factor (α) applied to the time domain of the NOW, and low-complexity minimum mean square error (MMSE)-ICI cancellation FDE (Frequency Domain Equalization) is preferably supported to cancel inter-symbol interference (ISI) and inter-subcarrier interference (ICI).

[0039] 3 shows an example of the configuration of a CP and OFDM symbols before and after FTN modulation (compression) in the time domain. Specifically, FIG. 3 shows the OFDM symbols shown in FIG. 2 in more detail.

[0040] As shown in FIG. 3, the CP length (N_CP^α) based on the compression coefficient α can be expressed as follows:

[0041]

number

[0042] 3, the CP length may be expressed as TCP in relation to the symbol time (TU). TU and TCP may be expressed in units of time (for example, μsec).

[0043] As shown in FIG. 3, the symbol length including the CP before the time domain compression by FTN can be expressed as follows:

[0044]

number

[0045] Furthermore, the symbol length including the CP after time domain compression by FTN can be expressed as follows:

[0046]

number

[0047] (2) Functional block configuration of wireless communication system Next, a description will be given of the functional block configuration of the wireless communication system 10. Specifically, the functional block configurations of the gNB 100 and the UE 200 will be described.

[0048] 4 is a schematic functional block diagram of the gNB 100 and the UE 200. The gNB 100 and the UE 200 have similar schematic functional block configurations, and therefore, the following description will be given taking the functional blocks of the UE 200 as an example.

[0049] As described above, in the wireless communication system 10, DFT-s-OFDM (applicable to both downlink (DL) and uplink (UL)) and FTN are applicable.

[0050] A limited number of RF chains can degrade the SE, but FTN can improve the SE by using compressed (squeezed) waveforms in the time domain.

[0051] It should be noted that the schematic functional block diagram shown in Fig. 4 mainly shows the parts related to FTN and DFT-s-OFDM. In Fig. 4, the related functional blocks are shown divided into the transmitting (TX) side and the receiving (RX) side.

[0052] As mentioned above, the non-orthogonal waveform (NOW) may be interpreted as being generated by a combination of DFT-s-OFDM and FTN in the time domain.

[0053] On the transmitting side, DFT-s-OFDM is used, and after modulation using the selected modulation method, DFT precoding (spreading) is performed, and subcarriers are mapped to symbols. Subcarriers are sine waves with different carrier frequencies, and the phase and amplitude of each subcarrier are set according to the type of symbol being transmitted. Here, the application of FTN is taken into consideration, and mapping is concentrated onto low-frequency subcarriers.

[0054] Then, an Inverse Fast Fourier Transform (IFFT) is performed on the multiple symbols to output a time signal sequence. The input multiple symbols are transmitted in parallel on individual subcarriers. A cyclic prefix (CP) is also added to the OFDM signal after the IFFT.

[0055] Furthermore, on the transmitting side, an FTN modulation module (time domain compression module) is provided after the CP addition, that is, after the DFT-s-OFDM.

[0056] The FTN modulation module multiplexes OFDM symbols at a rate faster than the Nyquist rate according to FTN, and specifically, the FTN modulation module has functions such as upsampling and waveform shaping after the sampling.

[0057] The receiver performs the reverse process of the transmitter described above. The receiver implements a frequency-domain equalization (FDE) function (MMSE-ICI cancellation FDE) based on the minimum mean square error (MMSE) criterion. This performs frequency-domain equalization based on the MMSE criterion, which can improve the bit error rate (BER) performance.

[0058] Specifically, the combination of DFT-s-OFDM with FDE and FTN can improve SE over DFT-s-OFDM alone at the expense of a moderate increase in signal-to-noise ratio (SNR), and the combination of DFT-s-OFDM with FDE and FTN can achieve similar BER and SE performance to that of CP-OFDM.

[0059] On the receiving side, an FTN demodulation module (time domain expansion module) is provided before the CP removal. The FTN demodulation module has a matched filter and a downsampling function.

[0060] The FTN modulation module and the FTN demodulation module transmit and receive slots consisting of multiple symbols (specifically, OFDM symbols, or FTN symbols after FTN). In this embodiment, the FTN modulation module and the FTN demodulation module constitute a transceiver unit.

[0061] A slot is a range (period) in the time direction (which may also be called the time domain) included in a radio frame. In this embodiment, 14 symbols / slot is supported, but slots including symbols that are an integer multiple of 14 symbols may also be supported.

[0062] The FTN modulation module and the FTN demodulation module may transmit and receive multiple types of radio frames with different slot patterns, which may mean that the numbers of UL symbols, DL symbols, and flexible symbols included in the radio frames, the symbol lengths, and / or the slot boundaries and / or symbol boundaries are different.

[0063] 4 controls each functional block constituting the transmitting side and receiving side of UE 200. In particular, in this embodiment, the control unit can set the length of a cyclic prefix (CP) to be added to a symbol (OFDM symbol) based on the degree of compression of the symbol in the time domain.

[0064] Specifically, the control unit can set the length of the CP based on a compression factor α applied to the time domain (i.e., the compression ratio applied to the time domain of the symbol (OFDM symbol)).

[0065] As mentioned above, α is a value indicating the compression rate of the time domain, and basically may take a value of 1.0 or less. When α=1.0, the time domain of the OFDM symbol (including CP) is not compressed. Note that the value of α may be expressed as the reciprocal or fraction of such a value.

[0066] When α is a value less than or equal to 1.0, the control unit may increase the length of the CP as the compression coefficient (α) decreases. For example, the control unit may increase the CP length when α=0.5 compared to when α=1.0.

[0067] Alternatively, the control unit may set the CP length associated with the minimum compression coefficient (αmin). Specifically, even if α takes multiple values ​​less than 1.0, the control unit may set the CP length associated with the minimum α (for example, 0.5).

[0068] The control unit can also set a compression coefficient associated with each of a plurality of different indices.

[0069] The multiple different metrics may be interpreted as target quality metrics, such as lossless transmission, PAPR optimization, or throughput optimization. The appropriate value of α may vary depending on the target quality metrics.

[0070] The control unit can set the value of α according to the target index. For example, when lossless assurance is the target, the control unit can set the value of α associated with lossless assurance. Similarly, when PAPR optimization is the target, the control unit can set the value of α associated with PAPR optimization, and when throughput optimization is the target, the control unit can set the value of α associated with throughput optimization.

[0071] Furthermore, when setting the value of α according to such an index, the control unit may set a compression coefficient according to a Modulation and Coding Scheme (MCS). That is, the control unit can set the value of α according to at least one of the modulation scheme and the coding rate for each target index.

[0072] Specifically, the control unit can set the value of α associated with the MCS index. The MCS index is specified in, for example, Chapter 5.1.3 of 3GPP TS38.214. The MCS index can take values ​​from 0 to 28. The modulation order (Qm, modulation method) and code rate (coding rate) are specified depending on the value of the MCS index.

[0073] For example, the control unit can set the value of α associated with MCS index 0, 10, or 28. The value of α associated with each MCS index may be one or more. Examples of the value of α associated with an MCS index will be described later.

[0074] Alternatively, when setting the value of α according to such an index, the control unit may set the compression coefficient based on a correspondence between the index and the compression coefficient, which may be defined for each target index (lossless assurance, PAPR optimization, or throughput optimization).

[0075] Specifically, the control unit may determine the value of α based on a table in which any index is associated with the value of α. The table may be configured for each target index.

[0076] Like the MCS index, this index may take a value between 0 and 28. That is, by utilizing the existing MCS index table (Chapter 5.1.3 of 3GPP TS38.214), a table in which any index is associated with the value of α may be configured.

[0077] Furthermore, when setting the value of α according to such an index, the control unit may set the value of α, that is, the compression coefficient, based on signaling in an upper layer from the network.

[0078] Specifically, the control unit can set the value of α based on signaling in a radio resource control layer (RRC). More specifically, an RRC parameter (which may be interpreted as an information element (IE)) that is specific to each target index or common to multiple indexes may be used. Examples of the parameter will be described later.

[0079] In addition, UE200 supports processing related to the specified reference signals, control signals, control channels, and data channels in order to perform wireless communication in accordance with NR.

[0080] For example, the UE 200 performs processing using reference signals (RS) such as a Demodulation Reference Signal (DMRS) and a Phase Tracking Reference Signal (PTRS).

[0081] DMRS is a reference signal (pilot signal) known between the base station and the terminal for estimating the fading channel used for data demodulation. PTRS is a terminal-specific reference signal for estimating phase noise, which is an issue in high frequency bands.

[0082] In addition to DMRS and PTRS, reference signals also include Channel State Information-Reference Signal (CSI-RS) and Sounding Reference Signal (SRS).

[0083] Furthermore, the UE 200 transmits and receives control signals such as RRC via a control channel.

[0084] The channels include a control channel and a data channel, such as a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), a physical random access channel (PRACH), and a physical broadcast channel (PBCH).

[0085] Furthermore, the data channel includes a PDSCH (Physical Downlink Shared Channel), a PUSCH (Physical Downlink Shared Channel), etc. Data may refer to data transmitted via a data channel.

[0086] The UE 200 also transmits and receives Protocol Data Units (PDUs) and Service Data Units (SDUs), and performs assembly / disassembly of PDUs / SDUs at multiple layers (e.g., Medium Access Control (MAC) layer, Radio Link Control (RLC) layer, and Packet Data Convergence Protocol (PDCP) layer).

[0087] (3) Operation of the wireless communication system Next, a description will be given of the operation of the wireless communication system 10. Specifically, the description will be given of the operation of the gNB 100 and the UE 200 performing compression of OFDM symbols in the time domain by FTN, setting the CP length based on the degree of compression, and setting the compression coefficient (α) associated with the target quality index (lossless assurance, PAPR optimization, or throughput optimization).

[0088] In the following, the operation of UE 200 will be described as an example.

[0089] (3.1) Premise In 5G Evolution or 6G, wide bandwidth usage in high frequency bands is expected. As mentioned above, FTN combined with DFT-s-OFDM can achieve high spectral efficiency (SE) and power efficiency (PE).

[0090] However, simply combining FTN and DFT-s-OFDM results in extremely complex processing. Therefore, in order to achieve high SE and PE while reducing complexity, this embodiment uses a non-orthogonal waveform (NOW), which is a combination of DFT-s-OFDM and FTN in the time domain. NOW can be applied to DL and / or UL.

[0091] To support reduced complexity NOW, the CP length is preferably set based on NOW parameters, specifically, the compression factor (α), which is preferably set according to different target quality metrics.

[0092] Figure 5 shows an example of a typical CP and OFDM symbol structure when FTN is not applied in the time domain. Specifically, CP is used to eliminate ISI caused by multipath delay. The CP length is determined based on the FFT size, SCS, and OFDM symbol index. Note that Extended CP is only supported with an SCS of 60 kHz.

[0093] The CP length can be expressed as follows:

[0094]

number

[0095] 5 shows an example of the configuration of CP and OFDM symbols when Δf=30 kHz and FFT size N_f=2048. The "I" in N_CP and I^μ means the OFDM symbol index. I can take a value from 0 to 27.

[0096] As shown in Fig. 5, when OFDM symbol index (l) = 0 or 14, the CP length is 160 samples. When OFDM symbol index (l) ≠ 0 or 14, the CP length is 144 samples.

[0097] 3GPP Release-15 and 16 (NR) assume the use of orthogonal waveforms and do not support NOW. Below, we explain how to set the CP length based on the compression rate in the time domain of an OFDM symbol (or slot), and how to set the compression coefficient (α) according to different target quality indicators.

[0098] (3.2) Operation overview Operation example 1 relates to setting the CP length based on the compression rate of the time domain of the OFDM symbol while using NOW.

[0099] Moreover, the second operational example relates to setting the compression coefficient (α) according to different target quality indicators.

[0100] Specifically, the first and second operation examples are configured as follows.

[0101] (Example 1) (Operational Example 1-1): The CP length is set based on the compression factor (α) as well as the FFT size, SCS, and (time domain) OFDM symbol index.

[0102] (Example 1-2): CP length setting operation (Example 1-2-1): Setting the CP length using the compression coefficient (α) (Example 1-2-2): Setting individual CP lengths by the RRC layer (Example 2) (Example 2-1): Defining a new table containing different target quality indicators (Example 2-2): Define a new table for each different quality indicator you want to target. (Example 2-3): Setting the α value using RRC layer parameters By using such Operation Example 1 or Operation Example 2, it is possible to configure a receiving device (UE or gNB) that can cancel ISI and ICI and has reduced complexity. Also, compared to the case where an orthogonal waveform is used, it is possible to achieve higher SE and PE.

[0103] The content of Chapter 5.3.1 of 3GPP TS38.211, which specifies the CP length, may be revised. For example, a new table related to the compression factor (α) may be specified. Furthermore, new signaling in the RRC layer, etc. may be specified.

[0104] (3.3) Example 1 In this operation example, the CP length is set based on the compression coefficient (α) as well. In the case of NOW, the CP has the following two functions.

[0105] Eliminates ISI caused by multipath delays.

[0106] Eliminates ISI caused by time-domain compression in FTN (a new feature unique to NOW).

[0107] (3.3.1) Example 1-1 In this example, the CP length is set based on the compression factor (α) as well as the FFT size, SCS, and (time domain) OFDM symbol index. When α=1, there may be an option to consider the influence of the pulse shaping filter when setting the CP length.

[0108] Specifically, options 1 and 2 shown below are included.

[0109] (Option 1): Setting the CP length taking into account the effect of the pulse shaping filter In this case, the CP length can be calculated as follows:

[0110]

number

[0111] (Option 2): Setting the CP length without considering the effect of the pulse shaping filter In this case, the CP length can be calculated as follows:

[0112]

number

[0113] 6 shows an example of the basic configuration of a CP and OFDM symbol according to operation example 1-1. In this operation example, the CP length can be expressed as follows:

[0114]

number

[0115] Here, L=0, 2, . . . , 2n may mean the length truncated from both sides before and after the pulse shaping filter of NOW.

[0116] Also, since a larger SCS may be supported in 5G Evolution or 6G, a larger SCS (μ) may be provided.

[0117] Fig. 7 shows an example of the configuration of the CP and OFDM symbols (α=1, option 1) according to the operation example 1-1. Fig. 8 shows an example of the configuration of the CP and OFDM symbols (α=1, option 2) according to the operation example 1-1.

[0118] 7 and 8 show an example of a configuration in which the SCS Δf = 30 kHz, the FFT size N_f = 2048, and the length truncated from both sides before and after the pulse shaping filter of NOW = 10. This can be expressed mathematically as follows:

[0119]

number

[0120] 7 and 8, the CP length is different between option 1 and option 2. Specifically, the CP length of option 1 is longer than the CP length of option 2.

[0121] Fig. 9 shows an example of the configuration of the CP and OFDM symbols (α=0.8) according to operation example 1-1. Fig. 10 shows an example of the configuration of the CP and OFDM symbols (α=0.5) according to operation example 1-1. The SCS, FFT size, etc. are the same as those in the configuration examples shown in Figs. 7 and 8.

[0122] 9 and 10, the CP length may be longer as the value of α becomes smaller (i.e., the compression ratio becomes higher). Specifically, the CP length when α=0.5 is longer than the CP length when α=0.8.

[0123] (3.3.2) Example 1-2 In this operation example, the CP length is set by implicit or explicit notification. Specifically, the CP length may be set implicitly according to a compression factor (α) (operation example 1-2-1). In this case, α may be a fixed value predefined in the 3GPP specifications, or may be set using RRC or downlink control information (DCI).

[0124] Alternatively, the CP length may be explicitly set using RRC (Operation Example 1-2-2). In this case, the following options may be set:

[0125] (Option 1): The CP length is set using RRC based on the minimum compression factor αmin In this case, a new RRC parameter (which may be an information element (IE) or a field constituting an IE), for example, NOW-minCompressionFactor, may be introduced to indicate α min.

[0126] Furthermore, only one αmin may be set, or multiple αmin may be set. When only one αmin is set, all α may belong to the same set.

[0127] On the other hand, if multiple α are set and the multiple α belong to different sets, α corresponding to each set may be set, or if α belongs to one of the multiple sets, α corresponding to that set may be used.

[0128] (Option 2): The CP length is set using RRC based on the compression factor α In this case, a new RRC parameter (which may be an information element (IE) or a field constituting an IE), for example, NOW-CompressionFactor, may be introduced to indicate α.

[0129] 11A, 11B, and 11C show a configuration example (part 1) of the CP and OFDM symbols according to operation example 1-2-2. Figures 11A, 11B, and 11C correspond to α=1, 0.8, and 0.5, respectively. Figures 11A, 11B, and 11C correspond to the above-mentioned option 1, and show a configuration example when only one αmin is set.

[0130] 11A, 11B, and 11C, the possible values ​​of α are 1, 0.8, and 0.5, and the smallest α, i.e., α=0.5, is set as αmin ({α=1, 0.8, 0.5}∈αmin=0.5). As a result, α=0.5 is applied to all, and the same CP length is set.

[0131] 12A, 12B, and 12C show a configuration example (part 2) of the CP and OFDM symbols according to operation example 1-2-2. Figures 12A, 12B, and 12C correspond to α=1, 0.8, and 0.5, respectively. Figures 12A, 12B, and 12C also correspond to the above-mentioned option 1, and show a configuration example when multiple αmins are set.

[0132] Specifically, as shown in Figures 12A, 12B, and 12C, the values ​​of α can be 1, 0.8, or 0.5, and the two smaller values ​​of α are set as αmin1 and αmin2 ({α=1, 0.8}∈αmin1=0.8; {α=0.5}∈αmin2=0.5). Therefore, αmin1=0.8 is applied to α=1 (Figure 12A).

[0133] In this operation example, the SCS, FFT size, and the like are the same as those in the configuration examples shown in FIGS.

[0134] (3.4) Example 2 In this operation example, a compression coefficient (α) is set according to different target quality indices. Specifically, as described above, α is set according to the indices of lossless transmission, PAPR optimization, or throughput optimization.

[0135] Note that ensuring losslessness may be interpreted as compressing the time domain while preventing any portion from being cut by a pulse shaping filter. Also, from the viewpoint of UE 200, a low PAPR is desirable, and therefore PAPR optimization may be interpreted as reducing the PAPR.

[0136] Throughput optimization may be interpreted as improving throughput (transmission speed) by setting a smaller α while ensuring a low BER.

[0137] Fig. 13 shows an example of a combination of a target index, MCS, and compression coefficient (α) according to operation example 2. As shown in Fig. 13, the calculation method of α may differ for each target quality index.

[0138] Furthermore, the calculation method of α may differ depending on the MCS, specifically, the modulation scheme (QPSK, 16QAM, 64QAM) and / or the Code Rate (CR).

[0139] (3.4.1) Example 2-1 In this example, a new table containing indexes of different target quality is defined. Figures 14, 15, and 16 show examples of tables of compression coefficients (α) according to Example 2-1. Specifically, the tables shown in Figures 14, 15, and 16 correspond to MCS 0, 10, and 28 (MCS index), respectively.

[0140] As shown in Figures 14, 15, and 16, a table may be used that defines multiple different values ​​of α associated with an MCS index. Also, different values ​​of α may be set depending on the MCS, such as lossless guarantee, PAPR optimization, or throughput optimization. Furthermore, values ​​of α other than those for the respective indicators (such as 0.9, 0.8, or 0.75) may be set.

[0141] Also, a new field (eg, CompressionFactor scaling) may be provided in the DCI to notify the compression factor (α).

[0142] (3.4.2) Example 2-2 In this operation example, a new table is defined for each different target quality index. Figures 17, 18, and 19 show examples of tables of compression coefficients (α) related to operation example 2-2. Specifically, the tables shown in Figures 17, 18, and 19 correspond to lossless assurance, PAPR optimization, and throughput optimization, respectively.

[0143] As shown in FIGS. 17, 18 and 19, a table may be used in which a number of different values ​​of α are defined in association with the target index.

[0144] Furthermore, in order to notify the compression coefficient (α) for each target indicator, new fields (for example, CompressionFactorLossless scaling, CompressionFactorPapr scaling, and CompressionFactorThroughput scaling) may be provided in the DCI.

[0145] (3.4.3) Example 2-3 In this operation example, the value of α is set using parameters of the RRC layer. Specifically, the following options may be set:

[0146] (Option 1): A new RRC layer parameter (e.g., NOW-CompressionFactorSet) is introduced, and a single α value is indicated for the target index.

[0147] In this case, if the parameter is not set, the UE 200 may assume a default value (eg, 1).

[0148] (Option 2): Three new RRC layer parameters (e.g., NOW-CompressionFactorLosslessSet, NOW-CompressionFactorPaprSet, NOW-CompressionFactorThroughputSet) are introduced, and three values ​​of α are indicated according to the target index.

[0149] Again, if the parameter is not set, the UE 200 may assume a default value (eg, 1).

[0150] (4) Actions and Effects According to the above-described embodiment, the following advantageous effects can be obtained: Specifically, the UE 200 can set the length of a cyclic prefix (CP) to be added to a symbol (OFDM symbol) based on the degree of compression of the symbol in the time domain.

[0151] Therefore, even when FTN in the time domain and DFT-s-OFDM are combined, it is possible to set an appropriate CP according to the degree of compression.

[0152] In this embodiment, the UE 200 can set the CP length based on the compression coefficient α applied to the time domain, and can therefore quickly and easily set an appropriate CP length according to the compression rate of the time domain using FTN or the like.

[0153] In this embodiment, the UE 200 can increase the CP as the compression factor (α) decreases, so that stable symbol reception can be continued even when the compression rate in the time domain is high.

[0154] In this embodiment, the UE 200 can set the CP length associated with the minimum compression factor (α min ), which allows for more reliable continued symbol reception even when multiple α's are used.

[0155] The UE 200 may also set compression factors associated with each of a plurality of different target metrics (lossless ensured, PAPR optimized, or throughput optimized).

[0156] Therefore, it is possible to set an appropriate compression rate in the time domain according to the index to be optimized.

[0157] In this embodiment, the UE 200 can set the value of α according to at least one of the modulation scheme and the coding rate for each target index, and can therefore set an appropriate compression coefficient (α) according to the combination of the target index and the MCS.

[0158] In this embodiment, when setting the value of α according to such an index, the UE 200 can set the compression coefficient based on the correspondence between an arbitrary index or an index similar to the MCS index and the compression coefficient. Therefore, for example, the compression coefficient can be flexibly set while following the same configuration as the MCS index.

[0159] In this embodiment, when setting the value of α according to such an indicator, the UE 200 can set the value of α, i.e., the compression coefficient, based on signaling in a higher layer (such as RRC) from the network. Therefore, an appropriate value of α can be set under the initiative of the network.

[0160] (5) Other embodiments Although the embodiments have been described above, it will be obvious to those skilled in the art that the present invention is not limited to the description of the embodiments and that various modifications and improvements are possible.

[0161] For example, in the above-described embodiment, an example was described in which the compression coefficient in the time domain changes due to FTN, but such a compression coefficient in the time domain does not necessarily have to be based on FTN. In other words, regardless of the modulation method such as FTN, the compression coefficient (compression rate) in the time domain may simply be defined.

[0162] In the above-described embodiment, an example in which FTN in the time domain and DFT-s-OFDM are combined has been described, but such a combination is not necessarily required.

[0163] Furthermore, the block diagram (FIG. 4) used in the description of the above-described embodiment shows functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are connected directly or indirectly (for example, by wire, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or the multiple devices with software.

[0164] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how each is implemented.

[0165] Furthermore, the above-described UE 200 may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 20 is a diagram showing an example of the hardware configuration of the UE 200. As shown in Fig. 20, the UE 200 may be configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0166] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the apparatus may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0167] Each functional block of the UE 200 (see FIG. 4) is realized by any hardware element of the computer device, or a combination of the hardware elements.

[0168] In addition, each function in UE200 is realized by loading specified software (programs) onto hardware such as processor 1001, memory 1002, etc., so that processor 1001 performs calculations, controls communication by communication device 1004, and controls at least one of reading and writing data in memory 1002 and storage 1003.

[0169] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, and the like.

[0170] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-mentioned embodiments. Furthermore, the various processes described above may be executed by one processor 1001, or may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0171] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store a program (program code), a software module, etc., that can execute a method according to an embodiment of the present disclosure.

[0172] Storage 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned recording medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0173] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module.

[0174] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0175] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0176] Furthermore, each device such as the processor 1001 and the memory 1002 is connected to a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0177] Furthermore, the device may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0178] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0179] Each aspect / embodiment described in the present disclosure may be applied to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, a 4th generation mobile communication system (4G), a 5th generation mobile communication system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable system, and a next-generation system extended based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A and 5G) may also be applied.

[0180] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0181] In the present disclosure, a specific operation described as being performed by a base station may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0182] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0183] The input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. The input and output information may be overwritten, updated, or added to. The output information may be deleted. The input information may be sent to another device.

[0184] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0185] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0186] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0187] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0188] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0189] Note that terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0190] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0191] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0192] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0193] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0194] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head: RRH)).

[0195] The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage area.

[0196] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0197] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0198] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0199] Furthermore, a base station in the present disclosure may be read as a mobile station (user terminal, the same applies hereinafter). For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a mobile station is replaced with communication between multiple mobile stations (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the mobile station may be configured to have the functions of a base station. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as uplink channel and downlink channel may be read as side channel.

[0200] Similarly, a mobile station in the present disclosure may be interpreted as a base station, in which case the base station may have the functions of a mobile station. A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0201] Numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by a transceiver in the frequency domain, and specific windowing operations performed by a transceiver in the time domain.

[0202] A slot may consist of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) A slot may be a numerology-based time unit.

[0203] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0204] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0205] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

[0206] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0207] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0208] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0209] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0210] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0211] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0212] The time domain of an RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each TTI, subframe, etc. may be composed of one or more resource blocks.

[0213] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0214] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0215] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0216] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0217] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0218] The above-described structures of the radio frame, subframe, slot, minislot, and symbol are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

[0219] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0220] The reference signal may also be abbreviated as Reference Signal (RS), and may also be called a pilot depending on the applicable standard.

[0221] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0222] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0223] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed therein or that the first element must precede the second element in some way.

[0224] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0225] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0226] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0227] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0228] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]

[0229] 10. Wireless communication systems 20 NG-RAN 100 gNB 200 UE 1001 processor 1002 memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output Device 1007 Bus

Claims

1. a transmitter that adds a cyclic prefix to a symbol and transmits the symbol; a control unit that sets a length of the cyclic prefix to be long when the symbol is compressed in a time domain; the degree of compression is based on a compression factor applied to the time domain; The control unit sets the length of the cyclic prefix associated with the minimum compression coefficient.

2. Send the symbol with a cyclic prefix, When the symbols are compressed in the time domain, setting the length of the cyclic prefix to be long; the degree of compression is based on a compression factor applied to the time domain; A transmitting method for a transmitting device, the transmitting device setting the length of the cyclic prefix associated with the minimum compression factor.

Images