Communication Equipment

Abstract

The communication device modulates the transmission bit sequence according to the modulation method, performs phase rotation on the modulated signal, and controls the phase rotation using an order of the second order or higher.

Description

Technical Field

[0001] The present invention relates to a communication device for performing phase rotation on a modulated signal. Background Art

[0002] In the 3rd Generation Partnership Project (3GPP), Long Term Evolution (LTE) was standardized, LTE-Advanced (hereinafter referred to as LTE including LTE-Advanced) was standardized for the purpose of further speeding up LTE, and the standardization of the fifth generation mobile communication system (5th generation mobile communication system) (also called 5G, New Radio (NR) or Next Generation (NG)) was promoted.

[0003] In 5G NR (Release 15), the maximum supported millimeter wave frequency is 52.6 GHz. In Release 16 and later versions, operations in bands exceeding 52.6 GHz are also studied.

[0004] When the carrier frequency is very high, the increase of phase noise and propagation loss becomes a problem. In addition, the signal becomes more sensitive to the peak-to-average power ratio (PAPR) and the nonlinearity of the power amplifier.

[0005] Therefore, Release 15 stipulates a method for reducing PAPR by performing phase rotation (also called constellation rotation: CR) in the IQ (In-phase, Quadrature) plane on the modulation signal (modulation codeword) based on BPSK (Binary Phase Shift Keying) when using DFT-S (Discrete Fourier Transform-Spread)-OFDM (Orthogonal Frequency Division Multiplexing) (refer to non-patent document 1).

[0006] Specifically, after the subcarrier symbol is modulated according to BPSK, the modulated signal is sequentially subjected to a phase rotation of π / 2 (90 degrees) (π / 2-shift BPSK). As a result, the phase of the modulated signal is evenly distributed, which can suppress the peak component after the inverse Fourier transform (IFFT), thereby effectively reducing the PAPR of the transmitted signal.

[0007] Prior art literature

[0008] Non-patent literature

[0009] Non-patent document 1: 3GPP TS 38.211 V15.5.0, 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical channels and modulation (Release 15), 3GPP, March 2019 Summary of the invention

[0010] Problem that the invention aims to solve

[0011] However, the PAPR reduction effect of the above-mentioned fixed phase rotation of π / 2 is limited when applied to multi-level modulation methods such as QAM (Quadrature Amplitude Modulation). Specifically, π / 2 is not necessarily the best phase rotation angle, and the best angle varies depending on the modulation method and system bandwidth.

[0012] In addition, in the case of CP (Cyclic Prefix) OFDM which is a multi-carrier transmission method, the effect of reducing PAPR by phase rotation is more limited than in the case of DFT-S-OFDM.

[0013] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a communication device that can effectively reduce PAPR using phase rotation regardless of an applied modulation method or the like.

[0014] One embodiment of the present invention provides a communication device (e.g., gNB100), which has a modulation unit (modulation unit 110) that modulates a transmission bit sequence according to a modulation method; and a control unit (control unit 180) that performs phase rotation on a modulated signal modulated by the modulation unit, and the control unit controls the phase rotation using an order of the second order or higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a diagram schematically showing the overall structure of the wireless communication system 10 .

[0016] Figure 2 This is a functional block structure diagram of gNB100, UE200A and UE200B.

[0017] Figure 3 This is an explanatory diagram of the modulation operation of the transmission bit sequence in the case of uplink (UL) or downlink (DL) for a specific UE, and the notification operation of information indicating the state of phase rotation for the modulated signal.

[0018] Figure 4 This is an explanatory diagram of a modulation operation of a transmission bit sequence in the case of DL multi-user or multi-channel, and a notification operation of information indicating a phase rotation state for a modulated signal.

[0019] Figure 5A is a diagram showing an example of phase rotation based on a fixed angle.

[0020] Figure 5B : is a diagram showing an example of using a high-order phase rotation (based on BPSK) of an order of two.

[0021] Figure 6 : is a diagram showing an example of a table indicating combinations of an index, a phase rotation sequence (k), and an order (o).

[0022] Fig. 7A This is a diagram showing simulation results of CCDF (Complementary Cumulative Distribution Function) characteristics for each combination of modulation method and phase rotation.

[0023] Figure 7B Yes Fig. 7A The upper left portion shown is an enlarged view (7.5 dB to 8.5 dB range).

[0024] Figure 8 It is a diagram showing the time domain response (simulation result) for each type (order) of phase rotation.

[0025] Fig. 9 This is a diagram showing an example of the hardware structure of gNB100, UE200A and UE200B. DETAILED DESCRIPTION

[0026] Hereinafter, the embodiments will be described based on the drawings. In addition, the same or similar reference numerals are given to the same functions and structures, and the description thereof will be appropriately omitted.

[0027] (1) Overall schematic structure of wireless communication system

[0028] Figure 1 1 is an overall schematic diagram of the wireless communication system 10 involved in this embodiment. The wireless communication system 10 is a wireless communication system based on 5G New Radio (NR), which includes a Next Generation-Radio Access Network 20 (next generation radio access network) (hereinafter referred to as NG-RAN 20), and a user terminal 200A and a user terminal 200B (hereinafter referred to as UE200A and UE200B).

[0029] NG-RAN 20 includes a radio base station 100 (hereinafter referred to as gNB 100). In addition, the specific structure of the wireless communication system 10 including the number of gNBs and UEs is not limited to Figure 1 Example shown. In this embodiment, gNB100, UE200A and UE200B constitute a communication device.

[0030] NG-RAN20 actually includes multiple NG-RAN nodes (NG-RAN Node), specifically gNB (and ng-eNB), which are connected to the core network (5GC or NGC, not shown) based on 5G. In addition, NG-RAN20 and 5GC can be simply expressed as "network".

[0031] gNB100 is a 5G-based wireless base station that performs 5G-based wireless communications with UE200A. gNB100 and UE200A can support Massive MIMO (Massive MIMO) that generates a more directional beam by controlling wireless signals sent from multiple antenna elements, Carrier Aggregation (CA) that bundles and uses multiple Component Carriers (CCs), and Dual Connectivity (DC) that simultaneously communicates between the UE and two NG-RAN nodes.

[0032] In addition, the wireless communication system 10 supports a plurality of frequency regions (FR). Specifically, the wireless communication system 10 supports FR1 and FR2. The frequency band of each FR is as follows.

[0033] FR1: 410MHz~7.125GHz

[0034] FR2: 24.25 GHz to 52.6 GHz

[0035] In FR1, a sub-carrier spacing (SCS) of 15, 30 or 60 kHz is used, and a bandwidth (BW) of 5 to 100 MHz is used. FR2 is a higher frequency than FR1, using an SCS of 60 or 120 kHz (including 240 kHz) and a bandwidth (BW) of 50 to 400 MHz.

[0036] In addition, SCS can be interpreted as a numerology. The numerology is defined in 3GPP TS 38.300 and corresponds to a subcarrier spacing in the frequency domain.

[0037] In addition, in addition to FR1 and FR2, the wireless communication system 10 may also support high frequency bands exceeding 52.6 GHz.

[0038] In addition, similar to LTE, the wireless communication system 10 can use CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) as a multiplexing method (radio access method). CP-OFDM can be used in downlink (DL) and uplink (UL).

[0039] Alternatively, the wireless communication system 10 may also use DFT-S-OFDM (Discrete Fourier Transform-Spread-OFDM, DFT spread OFDM) as a multiplexing method. DFT-S-OFDM can be used as a supplement to CP-OFDM. In addition, DFT-S-OFDM can be used only for UL or in both DL and UL.

[0040] In CP-OFDM, the PAPR (Peak to Average Power Ratio) increases and becomes larger than before, resulting in a decrease in the efficiency of the power amplifier, and the accompanying increase in power consumption, degradation of UL coverage, and increase in terminal costs. From the perspective of such problems, DFT-S-OFDM is more advantageous than CP-OFDM.

[0041] CP-OFDM can be used when the propagation loss between gNB100 and UE200A is small, or when the transmission bandwidth is narrow and the above problems are not significant, in other cases, DFT-S-OFDM is used. The network can determine which multiplexing method (radio access method) to use.

[0042] In addition, in the wireless communication system 10, a modulation method using so-called phase rotation (Phase Rotation) is introduced, similar to the π / 2-shift BPSK introduced in NR Release 15, in which the phase in the IQ plane is different for each modulation symbol. As is well known, "I" in the IQ plane stands for In-Phase (in-phase component, x-axis), and "Q" stands for Quadrature (quadrature component, y-axis), which represents a component in phase (phase 0 degrees) and a component in quadrature (phase 90 degrees) with the carrier serving as a reference.

[0043] As a modulation method, BPSK (Binary Phase Shift Keying: binary phase shift keying, 2 values), QPSK (Quadrature Phase shift Keying: quadrature phase shift keying, 4 values), and various QAM (Quadrature Amplitude Modulation: quadrature amplitude modulation), such as 16QAM, 64QAM and 256QAM, can be used. In addition, this modulation method is called a first-order modulation method, and CP-OFDM and DFT-S-OFDM are called second-order modulation methods.

[0044] Phase rotation may be referred to as constellation rotation (CR) from multiple coordinates on the IQ plane, or may be referred to as phase shift, etc. In addition, a modulation symbol may be referred to as a subcarrier, a subcarrier symbol, or simply a modulation signal, etc. In addition, modulation symbol, subcarrier, subcarrier symbol, modulation signal, etc. may be interchangeable.

[0045] In this embodiment, the wireless communication system 10 uses an order of the second order or higher to dynamically change the amount of phase rotation for each modulation signal (modulation symbol), rather than a fixed angle (π / 2, 90 degrees) such as π / 2-shift BPSK. The details of this phase rotation will be further described later.

[0046] (2) Functional block structure of communication device

[0047] Figure 2 This is a functional block diagram of gNB100, UE200A, and UE200B that constitute the communication device. Specifically, Figure 2 The functional block structure of the transmission side of the communication device using CP-OFDM is shown, and the functional block structure of the reception side is omitted. Figure 2 Only the functional blocks related to the above-mentioned phase rotation of the modulation signal are shown. In addition, in the following description, gNB100 is used as an example.

[0048] like Figure 2 As shown, gNB100 has a modulation unit 110, a codeword mapping unit 120, a subcarrier allocation unit 130, an IFFT processing unit 140, a CP adding unit 160, a wireless transmission unit 170, a control unit 180 and a notification signal sending unit 190.

[0049] The modulation unit 110 modulates the transmission bit sequence according to the modulation method. Specifically, the modulation unit 110 selects an arbitrary modulation method (for example, QPSK, 16QAM, etc.) from a plurality of predetermined modulation methods.

[0050] In this communication device, CP-OFDM is applied as described above. This communication device is a digital communication, and all information (sound and files, etc.) is sent as an information bit sequence of 0 or 1. In addition, data in the DL direction is sent via PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel) or PBCH (Physical Broadcast Channel).

[0051] The symbol mapping unit 120 performs mapping to symbols expressed by vectors according to the modulation method selected by the modulation unit 110. The mapping method depends on the modulation method such as QPSK or 16QAM.

[0052] For example, in the case of QPSK, the phase of the subcarrier (radio wave) is changed into four patterns to transmit information. In this case, there are also four types of symbols, and each symbol transmits 2 bits of information.

[0053] In addition, in the case of 16QAM, the combination of the amplitude and phase of the subcarrier (radio wave) radio wave is changed into 16 patterns to transmit information. In this case, there are also 16 types of symbols, and 4 bits of information are transmitted per symbol.

[0054] The subcarrier allocation unit 130 allocates a plurality of subcarriers having different carrier frequencies to the symbols (modulation symbols) output from the symbol mapping unit 120. A subcarrier is a sinusoidal wave having different carrier frequencies, and the phase and amplitude of each subcarrier are set according to the type of symbol to be transmitted.

[0055] The IFFT processing unit 140 performs an inverse fast Fourier transform (IFFT) on a plurality of symbols simultaneously input from the subcarrier allocation unit 130, and outputs a time signal sequence. The input plurality of symbols are transmitted in parallel through separate subcarriers.

[0056] The CP adding unit 160 adds a cyclic prefix (CP) to the OFDM signal output from the IFFT processing unit 140 .

[0057] As described above, CP-OFDM is used in the wireless communication system 10. CP-OFDM is a type of OFDM method that provides a guard time, CP, between symbols in order to suppress interference between previous and next symbols caused by multipath, etc. That is, CP can also be called a guard interval or a guard interval.

[0058] The CP is inserted into the beginning of an OFDM symbol. Generally, the CP is obtained by copying the second half of an OFDM symbol. In addition, an OFDM symbol refers to a unit of data to be transmitted and is composed of a plurality of subcarriers.

[0059] Furthermore, as described above, in this embodiment, CP-OFDM is mainly used, but DFT-S-OFDM may also be used.

[0060] The wireless transmission unit 170 performs processing such as DAC (digital-analog conversion), transmission filtering, power amplification, and frequency up-conversion on the OFDM signal output from the CP adding unit 160. The transmission signal is transmitted as a wireless signal to the destination communication device via an antenna.

[0061] The control unit 180 controls each functional block constituting the gNB 100. In particular, in the present embodiment, the control unit 180 performs phase rotation on the modulated signal modulated by the modulation unit 110.

[0062] The control unit 180 controls the modulation unit 110 and the symbol mapping unit 120 , and controls the amount of phase rotation of a symbol (modulation symbol) on the IQ plane according to the modulation method selected by the modulation unit 110 .

[0063] Specifically, the control unit 180 controls the phase rotation for the symbol using an order of the second order or higher. More specifically, when the order is set to "o" and the index of the modulated signal to be modulated sequentially is set to "n", the control unit 180 controls the phase rotation for the symbol according to n. o Controls phase rotation.

[0064] For example, when the index n of the modulation signal (symbol) modulated sequentially is set to 1, 2, 3, ..., and the order is set to "2", the control unit 180 2 (=1)、2 2 (=4)、3 2 The value of (=9) is used to sequentially change the amount of phase rotation. In addition, examples of angles applicable to specific phase rotations will be described later.

[0065] In addition, the control unit 180 can also use a plurality of phase rotation modes with different amounts and / or methods of phase rotation of the symbol for control. The plurality of phase rotation modes can be generated by changing the reference angle (which can also be referred to as the reference frequency parameter of the phase rotation) or by changing the above-mentioned order. Alternatively, the plurality of phase rotation modes can be generated by changing both the reference angle and the order.

[0066] In addition, the control unit 180 may generate multiple signal waveforms (also referred to as phase rotation sequences) using multiple phase rotation patterns with different amounts and / or methods of phase rotation. The control unit 180 may select a signal waveform with a lower peak-to-average power ratio (PAPR) from among the generated multiple signal waveforms.

[0067] In this case, the control unit 180 may select the signal waveform with the lowest PAPR, or may select any one of the signal waveforms with a PAPR equal to or less than a predetermined threshold.

[0068] The notification signal transmitter 190 may transmit a notification signal to a destination communication device such as UE200A as a communication target. Specifically, the notification signal transmitter 190 transmits information indicating a phase rotation state to the destination communication device as a notification signal. In this embodiment, the notification signal transmitter 190 constitutes a transmitter.

[0069] The notification signal transmission unit 190 can transmit the notification signal using a plurality of transmission methods. Specifically, the notification signal transmission unit 190 transmits information indicating the state of phase rotation for the modulated signal to the destination communication device using a cyclic prefix (CP).

[0070] More specifically, the notification signal transmission unit 190 can modulate the information indicating the state of phase rotation and multiplex it in the CP in which a part of the OFDM symbol is copied. In addition, the notification signal transmission unit 190 can also replace part or all of the CP with a UW (Unique-Word) prefix that can identify the information indicating the state of phase rotation.

[0071] Therefore, the information indicating the state of phase rotation may be information directly indicating the selected signal waveform (phase rotation sequence), or may be information of an index associated with the state of phase rotation as described below.

[0072] In addition, the notification signal transmission unit 190 may transmit information indicating the state of phase rotation for the modulated signal to the destination communication device using a common channel with the destination communication device or a reference signal (RS). In addition, the specific method of transmitting the notification signal will be further described later.

[0073] (3) Operation of the communication device

[0074] Next, the operations of gNB100, UE200A, and UE200B constituting the communication device are described. Specifically, the modulation operation of the transmission bit sequence performed by the communication device and the notification operation of information indicating the state of the phase rotation of the modulated signal are described.

[0075] (3.1) Modulation of the transmitted bit sequence

[0076] Figure 3 This is an illustration of the modulation operation of transmitting a bit sequence in the case of an uplink (UL) or a downlink (DL) for a specific UE, and the notification operation of information indicating the state of phase rotation for the modulated signal. The following is an explanation using DL transmission performed by gNB100 as an example.

[0077] like Figure 3 As shown, the transmitted bit sequence of the UE or the channel is modulated according to a predetermined modulation method (BPSK, QPSK, 16QAM, etc.).

[0078] gNB100 uses multiple phase rotation patterns with different phase rotation amounts (Phase rotation pattern 1, 2, ...M in the figure) to change the phase rotation amount of the modulated codewords.

[0079] The phase rotation of the modulation symbol (constellation rotation) is equivalent to the phase rotation in the frequency domain. The response in the time domain is very important for the reduction of PAPR.

[0080] In this embodiment, the time domain response of multiple signal waveforms (phase rotation sequences) generated using the multiple phase rotation patterns is analyzed, and the PAPR is controlled. In addition, in this embodiment, as described above, the phase rotation for the codeword is controlled using a second-order or higher-order order (hereinafter appropriately abbreviated as "high-order phase rotation" or "high-order phase shift"), but constellation rotation using a ZC (Zadoff-Chu) sequence can also be applied.

[0081] like Figure 3 As shown, gNB100 is capable of generating multiple phase rotation modes and sets of the phase rotation modes. As described above, multiple phase rotation modes can be generated by changing the reference angle (π / 2, etc.) or by changing the above-mentioned order. In addition, different modulation methods can be combined in the set of phase rotation modes.

[0082] Furthermore, the parameters included in the phase rotation pattern, such as the order to be applied, may be appropriately notified by the network.

[0083] gNB100 uses such multiple phase rotation patterns or a set of phase rotation patterns to generate multiple signal waveforms (phase rotation sequences) and compares the PAPR of the signal waveforms.

[0084] As described above, gNB100 can select the signal waveform with the smallest PAPR, but can also select any one of the signal waveforms with a PAPR below a predetermined threshold.

[0085] gNB100 generates a notification signal including the selected signal waveform, that is, including information indicating the state of phase rotation, and sends the generated notification signal to a destination communication device such as UE200A.

[0086] Figure 4 The present invention is an explanatory diagram of the modulation operation of the transmission bit sequence in the case of DL multi-user or multi-channel, and the notification operation of the information indicating the state of phase rotation of the modulation signal. Figure 3 The different parts of the uplink (UL) or downlink (DL) for a specific UE are described below.

[0087] like Figure 4 As shown, in the case of DL multi-user or multi-channel, after the transmission bit sequences to multiple UEs (UE 1, 2, ... N in the figure) are modulated respectively, the modulated signals are multiplexed in the frequency domain. Figure 3 It's the same.

[0088] (3.1.1) Phase rotation mode

[0089] Next, the phase rotation pattern will be described in detail. First, the phase rotation pattern in π / 2-shift BPSK specified in 3GPP Release 15 will be described.

[0090] Specifically, in Release 15, π / 2-shift BPSK (abbreviated as π / 2-BPSK) can be used in combination with DFT-S-OFDM applied to UL. In π / 2-shift BPSK, a phase rotation (primary phase shift) of an angle (π / 2, 90 degrees) fixed according to the FFT size is performed.

[0091] The rotation vector is expressed as follows.

[0092] [Formula 1]

[0093]

[0094] Where, “n” is the subcarrier index, “k” is the reference frequency parameter for phase rotation, and “Nfft " is the FFT size. By k / N fft Controls the angle of phase rotation. This phase rotation (primary phase shift) has almost no gain in CP-OFDM, which is a multi-carrier transmission method.

[0095] Furthermore, in the case of phase rotation based on the above-mentioned ZC sequence, the rotation vector is expressed as follows.

[0096] [Formula 2]

[0097]

[0098] Where, “n” is the subcarrier index, “q” is the path of the ZC sequence, and “N ZC " is a prime number serving as the length of the ZC sequence. The ZC (Zadoff-Chu) sequence is a type of "Constant Amplitude Zero Auto Correlation (CAZAC) sequence" having the characteristics of a constant amplitude for a time index and a delta function for the autocorrelation function. Therefore, in the case of such a phase rotation based on the ZC sequence, since the length of the sequence must be a prime number, good performance can be achieved but flexibility is lacking.

[0099] In view of the problems of the conventional phase rotation, the present embodiment uses the above-mentioned high-order phase rotation (high-order phase shift).

[0100] In the high-order phase rotation, a second-order or higher phase rotation (phase shift) based on the FFT size is performed. In the case of the high-order phase rotation, the rotation vector is expressed as follows.

[0101] [Formula 3]

[0102]

[0103] Where, “n” is the subcarrier index, “k” is the reference frequency parameter for phase rotation, and “N fft " is the FFT size. By k / N fft Controls the angle of phase rotation, and the order of phase rotation is controlled by "o".

[0104] The high-order phase rotation can achieve the same performance as the above-mentioned ZC sequence-based phase rotation, but because there is no particular restriction on the length of the sequence, it is more flexible.

[0105] Figure 5A and Figure 5B An example of phase rotation of a modulated signal is shown. Specifically, Figure 5A An example of phase rotation based on a fixed angle is shown. In addition, Figure 5BAn example of using high-order phase rotation (based on BPSK) of two orders according to the present embodiment is shown.

[0106] like Figure 5A As shown in FIG. 1 , based on the same fixed-angle phase rotation (primary phase shift) as π / 2-shift BPSK, the signal point position of the constellation bitmap in the IQ plane (circular mark in the figure) is shifted by a fixed angle each time for each subcarrier symbol. Figure 5A and Figure 5B , an example based on π / 6 (30 degrees) is shown.

[0107] like Figure 5A As shown, subcarrier symbol 0 is located at 0 degrees (and 180 degrees, and the same applies below), and subcarrier symbols 1 and 2 are offset by 30 degrees (210 degrees) and 60 degrees (240 degrees), respectively.

[0108] On the other hand, Figure 5B As shown, when a high-order phase rotation of an order of two is used, the signal point positions of the constellation bitmap in the IQ plane (circular marks in the figure) are shifted for each subcarrier symbol, and the amount of phase rotation increases according to the order.

[0109] Specifically, subcarrier symbol 0 is located at 0 degrees (and 180 degrees), and subcarrier symbol 1 is located at 30 degrees (210 degrees). Figure 5A is the same. n = 1, order = 2, that is, 1 2 =1,π / 6(30 degrees).

[0110] Next, subcarrier symbol 2 is located at 120 degrees (300 degrees). n = 2, order = 2, that is, 2 2 =4,4π / 6 (120 degrees).

[0111] In addition, subcarrier symbol 3 is located at 270 degrees (90 degrees). n = 3, order = 2, that is, 3 2 =9,9π / 6 (270 degrees).

[0112] In addition, Figure 5B In the description, for the sake of convenience, binary BPSK is taken as an example, but other modulation methods such as QPSK or QAM can of course also be applied.

[0113] In addition, in high-order phase rotation using two or more orders, the final PAPR can be changed by the combination of parameters "k" and "o", so a waveform with a lower PAPR (i.e., a phase rotation pattern) is selected from a plurality of phase rotation patterns, i.e., waveforms generated by phase rotation based on the FFT size using a combination of parameters "k" and "o". This makes it possible to control the PAPR.

[0114] In this embodiment, for the sake of convenience, the order is described as 2, but the order may be larger. In addition, the above-mentioned set of phase rotation patterns may include a plurality of phase rotation patterns with different applied orders, that is, a mixture of different orders.

[0115] (3.1.2) Generation of multiple phase rotation patterns

[0116] Next, a method of generating a phase rotation pattern (and a set of phase rotation patterns) is described. In this embodiment, a plurality of phase rotation patterns are generated in order to perform appropriate high-order phase rotation.

[0117] As described above, phase rotation is performed based on the generated plurality of phase rotation patterns, and a signal waveform based on a phase rotation pattern with the minimum PAPR is selected. The selected phase rotation pattern is notified to a destination communication device such as UE200A via a notification signal (described later).

[0118] In addition, in the case of a ZC sequence, as shown below, in order to obtain an optimal phase rotation pattern that can minimize PAPR, a search path q is required.

[0119] [Formula 4]

[0120]

[0121] On the other hand, in the case of high-order phase rotation, as shown below, it is necessary to search for a reference frequency parameter (k) and an order (o) to find an optimal phase rotation pattern that can minimize the PAPR.

[0122] [Formula 5]

[0123]

[0124] In the case of high-order phase rotation and ZC sequence, the number of candidates for phase rotation modes can be reduced in consideration of computational complexity and signaling overhead reduction.

[0125] For example, regarding the path q for the ZC sequence, it can be from 1 to N ZC Alternatively, in the case of high-order phase rotation, the order (o) may be fixed and candidate values ​​of k (reference frequency parameter) may be selected at uniform intervals.

[0126] In addition, for example, in the FFT size (N fft ) is 256 points, the number of phase rotation patterns may be reduced to a number corresponding to a number set at an interval smaller than 256 points (e.g., 8 or 16 points).

[0127] That is, we can start from k=0,…,N fft -1 selects candidate values ​​at uniform intervals.

[0128] In addition, in the case of a plurality of phase rotation patterns including different orders mixed (mixed order phase shift), for example, it is possible to select from k=0, . . . , N fft The candidate values ​​of k and the candidate values ​​of o are uniformly selected from o=-1 and o=2, ...8, respectively.

[0129] (3.2) Notification of information indicating the state of phase rotation

[0130] Next, the design of a notification signal for notifying the destination communication device of information indicating the state of phase rotation will be described.

[0131] In the following design example, it is assumed that a value is selected from candidate values ​​of the reference frequency parameter "k" and the order "o" (see the following equation) selected for PAPR control.

[0132] [value 6]

[0133]

[0134] (3.2.1) Design Example 1

[0135] In this design example, information indicating the state of phase rotation, specifically, information on the phase rotation mode (i.e., information on k and o) is multiplexed in the CP part of the CP-OFDM codeword and sent so that the destination communication device, i.e., the receiving side, can detect the phase rotation mode selected by the OFDM codeword.

[0136] The following equation expresses the CP in which the information indicating the state of phase rotation is multiplexed.

[0137] [Formula 7]

[0138]

[0139] S cp (t) is the time domain signal of the original CP in the CP-OFDM symbol. S' cp (t) is the time domain signal of the CP after the phase rotation pattern information is multiplexed. "α" is a scheduling parameter. "m" is a non-negative integer that can be specified and used to optimize the detection performance.

[0140] (3.2.2) Design Example 2

[0141] In this design example, a prefix of a UW (Unique-Word) that can identify information indicating a phase rotation state is used instead of the pattern multiplexed in the CP in Design Example 1. This UW may be any data array that is not expressed as a CP-OFDM symbol.

[0142] When compared with Design Example 1, in this design example, a part or all of CP is replaced by the prefix of UW.

[0143] The following formula expresses the time domain signal (S) of the CP after the prefix replacement of UW. uw (t)).

[0144] [Formula 8]

[0145]

[0146] (3.2.3) Design Example 3

[0147] In this design example, a notification signal notifying information indicating the state of phase rotation is transmitted using a common channel or a reference signal (RS) with a destination communication device such as UE 200A.

[0148] Specifically, information indicating the state of phase rotation is transmitted using a common channel or a common RS constituting a time slot of a radio frame.

[0149] An example of such a notification signal (S(t)) including information indicating the state of phase rotation is expressed in the following equation.

[0150] [Formula 9]

[0151]

[0152] Among them, "N" is determined by the time length in the common channel or common RS used. In addition, the common channel can be, for example, a channel of the physical layer, or a high-layer channel of a layer higher than the physical layer. In addition, the common RS can be, for example, a DMRS (Demodulation reference signal) of a common channel, or a CSI-RS (Channel State Information Reference Signal).

[0153] Furthermore, particularly when a common channel is used, the selected phase rotation pattern can be determined based on an index indicating the generated phase rotation pattern.

[0154] Figure 6 An example of a table indicating combinations of an index, a reference frequency parameter (k) of phase rotation, and an order (o) is shown.

[0155] The "index" corresponds to a combination of a reference frequency parameter (k) and an order (o) of phase rotation. Figure 6 The contents of the table shown and the phase rotation mode used are known in the transmitting side and the receiving side, i.e., are shared. For example, when the index "1" is notified, the receiving side can recognize that k=32 and the order used is "2". Thus, the receiving side can determine how the phase rotation is implemented for the modulated signal.

[0156] In addition, instead of the index, the transmitting side may notify the value of k,o, or the transmitting side and the receiving side may share either one and notify only one side.

[0157] (3.2.4) Design Example 4

[0158] In this design example, downlink control information (DCI) is used to notify the index described in Design Example 3. That is, in this design example, Figure 6 The table shown is the same table.

[0159] In addition, there is no particular limitation on the DCI format to be applied, and any DCI format may be used as long as the index can be notified.

[0160] (3.2.5) Design Example 5

[0161] In this design example, the phase rotation pattern is notified by multiplexing the information of the selected phase rotation pattern into RS such as DMRS.

[0162] The following equation expresses the RS multiplexing the phase rotation pattern.

[0163] [Formula 10]

[0164]

[0165] S RS (n) is the original RS timing. RS It is the length of the RS sequence. In addition, RS other than DMRS (CSI-RS, etc.) may be used as long as the phase rotation pattern can be notified.

[0166] (3.2.6) Others

[0167] As in the above-mentioned Design Examples 1 to 5, in this embodiment, information indicating the state of phase rotation can be notified using OFDM symbols or time slots.

[0168] As in Design Example 1, the receiving side can use the CP and the corresponding part (segment) of the OFDM symbol to detect the selected phase rotation pattern.

[0169] Furthermore, when UW is used as in Design Example 2, the UW transmitted via the CP portion can function as a reference signal for notifying phase rotation.

[0170] In the case of Design Example 1 and Design Example 2, since the CP part of the OFDM signal is used, the load such as overhead does not increase.

[0171] In the case of Design Example 3, since a common channel or RS is used, group notification to multiple destination communication devices is possible. In addition, when DCI is used as in Design Example 4 or DMRS is used as in Design Example 5, individual notification to a destination communication device is possible.

[0172] In addition, the above-mentioned design examples of notification signals may be used in combination. For example, DCI may be used to notify some information (design example 4), DMRS may be used to notify the remaining information (design example 5), or one of the design examples 1 to 3 may be used to notify.

[0173] In addition, the notification using the common channel and the notification of the destination communication device may be combined. In this case, a common reference phase rotation pattern is notified to a plurality of destination communication devices in the common channel, and an offset value with respect to the common reference phase rotation pattern may be notified as the phase rotation pattern of each destination communication device.

[0174] Furthermore, the transmission of the notification signal is not necessarily limited to the case where a high-order phase rotation is used, and as described above, when a phase rotation using a ZC sequence is performed, it can be applied to notify the destination communication device of which phase rotation is performed.

[0175] Furthermore, as described above, in this embodiment, since the number of phase rotation patterns can be reduced, the receiving side does not need to receive such a notification signal, but can blindly calculate the phase rotation pattern with the minimum PAPR based on a plurality of pre-selected phase rotation patterns and make a decision.

[0176] (4) Action and Effect

[0177] Next, the action and effect of the high-order phase rotation performed by the communication device described above will be described. Fig. 7A and Figure 7B The performance evaluation results for each combination of modulation method and phase rotation are shown.

[0178] Specifically, Fig. 7AThe simulation results of CCDF (Complementary Cumulative Distribution Function) characteristics for each combination of modulation method and phase rotation are shown. Figure 7B Yes Fig. 7A The upper left portion shown is an enlarged view of the graph (7.5 dB to 8.5 dB range).

[0179] CCDF is the probability that a signal having a PAPR exceeding the value on the horizontal axis will occur in the generated OFDM symbol.

[0180] like Fig. 7A and Figure 7B As shown, when CCDF reference 10 -4 When the PAPR level (dB) is shown in FIG. 1 , the PAPR is effectively reduced when a high-order phase rotation of the second order or higher (2nd ord, 8th ord in the figure) is used.

[0181] In addition, in this simulation result, it is shown that all the FFT size (N fft )'s phase rotation reference frequency parameter (Full sequence, expressed as full in the figure), and the case of generating a phase rotation reference frequency parameter of a part of the FFT size (limiting the candidate values ​​to 128).

[0182] Even when phase rotation reference frequency parameters for a portion of the FFT size are generated and the phase rotation reference frequency parameters with the lowest PAPR are selected, PAPR in the same CCDF is reduced compared to using a first-order phase rotation.

[0183] Figure 8 The time domain response (simulation result) of each type (order) of phase rotation is shown. Figure 8 The horizontal axis of each graph corresponds to the time domain, and the vertical axis corresponds to the peak component of the signal.

[0184] like Figure 8 As shown in , when a phase rotation of the first order is used, the peak component of the signal will be prominent in a specific time domain, but in a phase rotation of the second order or higher, as the order becomes higher, the change in the peak component of the signal becomes less. Figure 8 As shown, the peak component suppression performance using the phase rotation of the ZC sequence is the highest.

[0185] Therefore, the phase rotation using the second-order or higher-order phase rotation or the phase rotation using the ZC sequence can be regarded as a sliding window operation on the time domain of the signal. As a result, the peak of the signal becomes smooth and the PAPR is reduced.

[0186] Phase rotation using a ZC sequence has the flattest time domain response, but has the above-mentioned disadvantages. That is, the length of the ZC sequence must be a prime number, which lacks flexibility. In actual applications, if discarding or filling operations occur, the excellent peak component suppression performance of the ZC sequence mentioned above will be destroyed.

[0187] In addition, in the case of a ZC sequence, the sequence and path (q) depend on the length of the data length (transmitted bit sequence) of the modulation object, which leads to disadvantages such as complexity of implementation and lack of flexibility, and the adaptability to various data lengths is also limited.

[0188] Higher-order phase rotations of the second order or higher can overcome the disadvantages of this ZC sequence. In addition, phase rotations that can effectively reduce PAPR can be applied not only to DFT-S-OFDM using π / 2-shift BPSK, but also to CP-OFDM and all multiplexing methods (second-order modulation methods).

[0189] Furthermore, since information indicating the state of the selected phase rotation can be notified to the receiving side through the notification signal, the receiving side (destination communication device) can easily determine the amount of phase rotation and perform demodulation and the like.

[0190] That is, according to gNB100 and UE200A, etc., the communication device can effectively reduce PAPR using phase rotation regardless of the modulation method applied.

[0191] (5) Other Implementation Methods

[0192] As mentioned above, although the content of this invention was demonstrated based on embodiment, this invention is not limited to these descriptions, Various deformation|transformation and improvement are possible for those skilled in the art, and it is obvious.

[0193] For example, a phase rotation pattern based on a high-order phase rotation may be specified as part of a modulation scheme or a data scrambling scheme.

[0194] In addition, high-order phase rotation can be turned on or off by signaling. In addition, groups of phase rotation modes can also be specified by specifications. Such a group is a set of candidate modes for reducing PAPR. In addition, dynamic notification of the phase rotation mode used in the transmission of the transmission bit sequence or periodic notification based on time slots or frames can also be considered.

[0195] In addition, in the above-mentioned implementation, 3GPP's NR (5G) is used as an example for explanation, but the above-mentioned high-order phase rotation can also be applied to a wireless or wired communication system using the same modulation method.

[0196] The block diagram used in the description of the above-mentioned embodiment ( Figure 2 ) shows blocks in units of functions. These functional blocks (structural parts) are implemented by any combination of at least one of hardware and software. In addition, there is no particular limitation on the implementation method of each functional block. That is, each functional block can be implemented using a device that is physically or logically combined, or two or more physically or logically separated devices can be directly or indirectly connected (for example, using wires, wirelessly, etc.) and implemented using these multiple devices. The functional block can also be implemented by combining software with the above-mentioned one device or the above-mentioned multiple devices.

[0197] Functionally, it includes judging, deciding, determining, calculating, calculating, processing, deriving, investigating, searching, confirming, receiving, sending, outputting, accessing, solving, selecting, selecting, establishing, comparing, assuming, expecting, regarding, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but is not limited to these. For example, the functional block (structural part) that enables the sending function is called a transmitting unit or a transmitter. In short, as mentioned above, there is no particular limitation on the implementation method.

[0198] In addition, the above-mentioned gNB100, UE200A and UE200B (the device) can also function as a computer that processes the wireless communication method disclosed in the present invention. Fig. 9 FIG. 1 is a diagram showing an example of the hardware structure of the device. Fig. 9 As shown, the device may also be configured as a computer device including a processor 1001, a memory 1002 (memory), a storage 1003 (storage), a communication device 1004, an input device 1005, an output device 1006, and a bus 1007.

[0199] In the following description, the word "device" may be replaced by "circuit", "device", "unit", etc. The hardware structure of the device may include one or more of the devices shown in the figure, or may exclude some of the devices.

[0200] Each functional block of the device (refer to Figure 2 ) can be implemented by any hardware element or combination of hardware elements of the computer device.

[0201] In addition, each function in the device is implemented by the following method: predetermined software (program) is read into hardware such as processor 1001 and memory 1002, so that processor 1001 performs calculations and controls the communication of communication device 1004 or controls at least one of the reading and writing of data in memory 1002 and storage 1003.

[0202] The processor 1001 controls the entire computer by, for example, running an operating system. The processor 1001 may be constituted by a central processing unit (CPU) including an interface with peripheral devices, a control device, a calculation device, a register, and the like.

[0203] In addition, the processor 1001 reads a program (program code), a software module or data, etc. from at least one of the memory 1003 and the communication device 1004 to the memory 1002, and performs various processes accordingly. As a program, a program that causes a computer to perform at least a part of the actions described in the above-mentioned embodiments is used. In addition, with respect to the above-mentioned various processes, although it is described that the above-mentioned various processes are performed by one processor 1001, the above-mentioned various processes can also be performed simultaneously or sequentially by more than two processors 1001. The processor 1001 can also be installed by more than one chip. In addition, the program can also be sent from the network via a telecommunication line.

[0204] The memory 1002 is a computer-readable recording medium, and may be composed of at least one of a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), a RAM (Random Access Memory), etc. The memory 1002 may also be referred to as a register, a cache, a main memory (main storage device), etc. The memory 1002 may store a program (program code), a software module, etc. that can execute a method according to an embodiment of the present disclosure.

[0205] The memory 1003 is a computer-readable recording medium, and may be composed of at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a floppy disk, a magneto-optical disk (e.g., a compressed disk, a digital versatile disk, a Blu-ray (registered trademark) disk, a smart card, a flash memory (e.g., a card, a stick, a key drive), a Floppy (registered trademark) disk, a magnetic strip, etc. The memory 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, other appropriate media such as a database, a server, etc. that includes at least one of the memory 1002 and the memory 1003.

[0206] The communication device 1004 is hardware (transceiver) used to communicate between computers via at least one of a wired network and a wireless network, and may also be called a network device, a network controller, a network card, a communication module, etc.

[0207] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like, for example, in order to realize at least one of frequency division duplex (FDD) and time division duplex (TDD).

[0208] The input device 1005 is an input device that receives input from the outside (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.). The output device 1006 is an output device that implements output to the outside (e.g., a display, a speaker, an LED light, etc.). In addition, the input device 1005 and the output device 1006 may also be integrally formed (e.g., a touch panel).

[0209] In addition, the processor 1001 and the memory 1002 and other devices are connected via a bus 1007 for communicating information. The bus 1007 may be configured using a single bus or may be configured using different buses for each device.

[0210] In addition, the device may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array), and a part or all of each functional block may be implemented by the hardware. For example, the processor 1001 may also be implemented using at least one of these hardware.

[0211] In addition, the notification of information is not limited to the form / implementation method described in the present disclosure, and other methods may also be used. For example, the notification of information may be implemented through physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), high-layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals or a combination thereof. In addition, RRC signaling may also be referred to as an RRC message, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

[0212] Each form / embodiment described in the present disclosure may also be applied to at least one of LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA 2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), a system using other appropriate systems, and a next-generation system extended therefrom. In addition, a combination of a plurality of systems (for example, a combination of at least one of LTE and LTE-A with 5G, etc.) may be applied.

[0213] The processing procedures, timings, processes, etc. of each form / implementation described in this disclosure may be changed in order without contradiction. For example, for the method described in this disclosure, the elements of various steps are presented in an illustrative order, but are not limited to the specific order presented.

[0214] In the present disclosure, specific actions performed by a base station are sometimes performed by its upper node depending on the situation. In a network consisting of one or more network nodes having a base station, various actions performed to communicate with a terminal can be performed by at least one of the base station and other network nodes other than the base station (for example, consider MME or S-GW, etc., but not limited to these). In the above, the case where there is one other network node other than the base station is illustrated, but the other network node may also be a combination of multiple other network nodes (for example, MME and S-GW).

[0215] Information, signals (information), etc. can be output from a higher layer (or lower layer) to a lower layer (or higher layer), and can also be input or output via multiple network nodes.

[0216] The input or output information can be stored in a specific location (e.g., memory) or managed using a management table. The input or output information can be rewritten, updated, or appended. The output information can also be deleted. The input information can also be sent to other devices.

[0217] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value (Boolean: true or false), or by comparison of numerical values ​​(for example, comparison with a predetermined value).

[0218] Each form / implementation described in the present disclosure may be used alone or in combination, and may be switched according to execution. In addition, notification of scheduled information is not limited to being performed explicitly (e.g., notification of "yes X"), but may also be performed implicitly (e.g., not notifying the scheduled information).

[0219] Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by other names, shall be interpreted broadly to refer to commands, sets of commands, codes, code segments, program codes, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, etc.

[0220] In addition, software, commands, information, etc. may be sent and received via a transmission medium. For example, when software is sent from a web page, server, or other remote source using at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and wireless technology (infrared, microwave, etc.), at least one of these wired technology and wireless technology is included in the definition of transmission medium.

[0221] The information, signals, etc. described in the present disclosure may also be represented by any of a variety of different technologies. For example, data, commands, instructions, information, signals, bits, symbols, chips, etc. that may be involved in the above description as a whole may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination thereof.

[0222] In addition, the terms described in the present disclosure and the terms required for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may also be a signal (signaling). In addition, a signal may also be a message. In addition, a component carrier (CC) may be referred to as a carrier frequency, a cell, a frequency carrier, etc.

[0223] The terms "system" and "network" used in this disclosure may be used interchangeably.

[0224] In addition, the information, parameters, etc. described in the present disclosure may be represented by absolute values, relative values ​​to predetermined values, or other corresponding information. For example, wireless resources may also be indicated by indexes.

[0225] The names used for the above parameters are not limiting in any way. Furthermore, the formulas etc. using these parameters may sometimes differ from those explicitly stated in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by appropriate names, and therefore the various names assigned to these various channels and information elements are not limiting in any way.

[0226] In the present disclosure, the terms "base station (BS)", "wireless base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", "carrier", "component carrier" and the like are used interchangeably. Base stations are sometimes referred to as macrocells, small cells, femtocells, picocells, etc.

[0227] A base station can accommodate one or more (for example, 3) cells. 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 also provide communication services through a base station subsystem (for example, a small base station for indoor use (RRH: Remote Radio Head)).

[0228] The terms "cell" or "sector" refer to a part or the entirety of a coverage area of ​​at least one of a base station and a base station subsystem that provide communication services within the coverage area.

[0229] In the present disclosure, terms such as “mobile station (MS)”, “user terminal (user terminal)”, “user equipment (UE)”, and “terminal” may be used interchangeably.

[0230] For mobile stations, those skilled in the art sometimes also use the following terms: 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 appropriate terms.

[0231] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a communication device, etc. In addition, at least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body may be a means of transportation (e.g., a car, an airplane, etc.), a mobile body that moves in an unmanned manner (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). In addition, at least one of the base station and the mobile station also includes a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0232] In addition, the base station in the present disclosure may also be replaced by a mobile station (user terminal, the same below). For example, regarding a structure in which the communication between a base station and a mobile station is replaced by communication between multiple mobile stations (for example, it may also be referred to as D2D (Device-to-Device), V2X (Vehicle-to-Everything, etc.), the various forms / implementations of the present disclosure may also be applied. In this case, it may also be a structure in which the mobile station has the functions of the base station. In addition, terms such as "uplink" and "downlink" may also be replaced by terms corresponding to communication between terminals (for example, "side"). For example, an uplink channel, a downlink channel, etc. may also be replaced by a side channel.

[0233] Likewise, the mobile station in the present disclosure may be replaced by a base station. In this case, the base station may have the same functions as the mobile station.

[0234] The terms "connected", "coupled" or all variations of these terms are intended to indicate any direct or indirect connection or combination between two or more elements, and may include the situation where there is one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The combination or connection between elements may be a physical combination or connection, a logical combination or connection, or a combination of these. For example, "access" may be used to replace "connection". In the context of the present disclosure, for two elements, it may be considered that they are "connected" or "coupled" to each other by using at least one of one or more wires, cables, and printed electrical connections, and as some non-limiting and non-inclusive examples, by using electromagnetic energy such as electromagnetic energy with wavelengths in the wireless frequency domain, microwave region, and light (including both visible and invisible) region.

[0235] The reference signal may be referred to as RS (Reference Signal) for short, or may be referred to as a pilot signal according to the applied standard.

[0236] The phrase "according to" used in the present disclosure does not mean "only according to" unless otherwise expressly stated. In other words, the phrase "according to" means both "only according to" and "at least according to".

[0237] Any reference to an element using the terms "first", "second", etc. used in this disclosure does not necessarily limit the number and order of these elements. These terms are used in this disclosure as a simple method to distinguish between two or more elements. Therefore, a reference to a first and a second element does not mean that only two elements can be used here or that the first element must precede the second element in any form.

[0238] When the terms "include," "including," and variations thereof are used in the present disclosure, these terms are intended to be inclusive, as is the term "comprising." Furthermore, the term "or" used in the present disclosure does not mean an exclusive or.

[0239] In the present disclosure, when an article is added by translation, such as a, an, and the in English, for example, the present disclosure also includes the case where the noun following the article is in plural form.

[0240] In the present disclosure, the phrase "A and B are different" may also mean "A and B are different from each other". In addition, the phrase may also mean "A and B are different from C, respectively". The phrases such as "separate" and "combine" may also be interpreted as "different".

[0241] A radio frame may be composed of one or more frames in the time domain. One or more frames in the time domain may also be referred to as subframes. A subframe may also be composed of one or more time slots in the time domain. A subframe may be a fixed time length (e.g., 1 ms) that is independent of a parameter set (numerology).

[0242] A parameter set may also be a communication parameter applied to at least one of the transmission and reception of a certain signal or channel. The parameter set may, for example, represent at least one of a subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, wireless frame structure, specific filtering processing performed by a transceiver in the frequency domain, specific windowing processing performed by a transceiver in the time domain, and the like.

[0243] A time slot may be composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.) in the time domain. A time slot may be a time unit based on a parameter set.

[0244] A time slot may also include multiple mini-slots. Each mini-slot may be composed of one or more symbols in the time domain. In addition, a mini-slot may also be referred to as a sub-slot. A mini-slot may also be composed of fewer symbols than a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot may also be referred to as a PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may also be referred to as a PDSCH (or PUSCH) mapping type B.

[0245] Radio frames, subframes, time slots, mini-time slots, and symbols all represent time units for transmitting signals. Radio frames, subframes, time slots, mini-time slots, and symbols may also be referred to by other corresponding names.

[0246] For example, 1 subframe may also be referred to as a transmission time interval (TTI), multiple consecutive subframes may also be referred to as a TTI, and 1 time slot or 1 mini time slot may also be referred to as a TTI. That is, at least one of the subframe and the TTI may be a subframe (1ms) in the existing LTE, or a period shorter than 1ms (for example, 1-13 symbols), or a period longer than 1ms. In addition, the unit representing the TTI may not be a subframe, but may be referred to as a time slot, a mini time slot, or the like.

[0247] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in the LTE system, the base station schedules each user terminal to allocate wireless resources (frequency bandwidth, transmission power, etc. that can be used in each user terminal) in units of TTI. In addition, the definition of TTI is not limited to this.

[0248] TTI can be a transmission time unit of data packets (transport blocks), code blocks, code words, etc. after channel coding, or a processing unit for scheduling, link adaptation, etc. In addition, when a TTI is assigned, the time interval (for example, the number of symbols) to which a transport block, code block, code word, etc. is actually mapped can also be shorter than the TTI.

[0249] In addition, when 1 time slot or 1 mini time slot is called TTI, more than 1 TTI (i.e., more than 1 time slot or more than 1 mini time slot) can also constitute the minimum time unit of scheduling. In addition, the number of time slots (mini time slots) constituting the minimum time unit of scheduling can also be controlled.

[0250] A TTI having a time length of 1 ms may be referred to as a normal TTI (TTI in LTE Rel.8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a time slot, etc. A TTI shorter than a normal TTI may be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a mini time slot, a sub time slot, a time slot, etc.

[0251] In addition, long TTI (e.g., normal TTI, subframe, etc.) can be replaced by TTI with a time length exceeding 1ms, and short TTI (e.g., shortened TTI, etc.) can also be replaced by TTI with a TTI length smaller than that of long TTI and greater than 1ms.

[0252] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain. In the frequency domain, it may also include one or more consecutive subcarriers. The number of subcarriers included in an RB may be the same regardless of the parameter set, for example, it may be 12. The number of subcarriers included in an RB may be determined based on the parameter set.

[0253] In addition, the time domain of an RB may include one or more symbols, and may be of the length of 1 slot, 1 mini slot, 1 subframe, or 1 TTI. 1 TTI, 1 subframe, etc. may also be composed of one or more resource blocks.

[0254] In addition, one or more RBs may also be referred to as a physical resource block (PRB: Physical RB), a sub-carrier group (SCG: Sub-Carrier Group), a resource element group (REG: Resource Element Group), a PRB pair, an RB pair, etc.

[0255] In addition, a resource block may be composed of one or more resource elements (REs). For example, 1 RE may be a radio resource region of 1 subcarrier and 1 symbol.

[0256] A bandwidth part (BWP) (also called partial bandwidth, etc.) may also represent a subset of continuous common RBs (common resource blocks) for a parameter set in a certain carrier. Here, common RBs may also be identified by the index of the RB based on the common reference point of the carrier. PRBs may also be defined by a BWP and numbered within the BWP.

[0257] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). For a UE, one or more BWPs may be configured within one carrier.

[0258] At least one of the configured BWPs may be activated, and the UE may not assume that it transmits or receives predetermined signals / channels other than the activated BWP. In addition, "cell", "carrier", etc. in the present disclosure may also be replaced by "BWP".

[0259] The above structures of radio frames, subframes, time slots, mini-time slots, and symbols are only examples. For example, the number of subframes included in a radio frame, the number of time slots in each subframe or radio frame, the number of mini-time slots included in a time slot, the number of symbols and RBs included in a time slot or mini-time slot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP: Cyclic Prefix) length, and the like can be variously changed.

[0260] The present disclosure is described in detail above, but it should be clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented as a modification and variation without departing from the subject matter and scope of the present disclosure as determined by the claims. Therefore, the purpose of the description of the present disclosure is to illustrate and not to have any limiting meaning on the present disclosure.

[0261] Description of labels:

[0262] 10 Wireless Communication Systems

[0263] 20 NG-RAN

[0264] 100 gNB

[0265] 110 Modulation Department

[0266] 120 Symbol mapping unit

[0267] 130 Subcarrier allocation unit

[0268] 140 IFFT processing unit

[0269] 160 CP additional part

[0270] 170 Wireless Transmission Unit

[0271] 180 Control Department

[0272] 190 Notification signal sending unit

[0273] 200A,200B UE

[0274] 1001 Processor

[0275] 1002 Memory

[0276] 1003 Memory

[0277] 1004 Communication device

[0278] 1005 Input Device

[0279] 1006 Output Device

[0280] 1007 Bus

Claims

1. A communication device, wherein: The communication device comprises: a modulation unit, which modulates the transmission bit sequence according to a modulation method; and a control unit that performs phase rotation on the modulated signal modulated by the modulating unit, The control unit dynamically changes the amount of the phase rotation for the modulation signal for each of the modulation signals using an order of second or higher order.

2. The communication device according to claim 1, wherein: When the order is set to "o" and the index of the modulated signal to be modulated sequentially is set to "n", the control unit o The phase rotation is controlled.

3. The communication device according to claim 1 or 2, wherein: The control unit selects a signal waveform having a low peak-to-average power ratio among a plurality of signal waveforms generated using a plurality of phase rotation patterns.

4. The communication device according to claim 1 or 2, wherein: The control unit selects a phase rotation mode and performs phase rotation on the modulated signal using the selected phase rotation mode; and The communication device further includes a transmission unit that transmits information indicating the state of the phase rotation to a destination communication device using a cyclic prefix.

5. The communication device according to claim 1 or 2, wherein: The control unit selects a phase rotation mode and performs phase rotation on the modulated signal using the selected phase rotation mode. The communication device further includes a transmission unit that transmits an index indicating the phase rotation pattern to a plurality of destination communication devices using a common channel or a reference signal. When the common channel is used, the plurality of destination communication devices determine the selected phase rotation pattern based on the index.

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