KR102463661B1 - Method and apparatus for signal modulation and demodulation in wireless communication system - Google Patents

Abstract

According to an embodiment of the present invention, a method of operating a first communication node in a communication system includes mapping data symbols to be transmitted to a second communication node of the communication system to resources on a first two-dimensional (2D) domain. , preprocessing the data symbols mapped to the resources on the first 2D domain to spread the data symbols on the resources on the second 2D domain, the preprocessed data symbols on the second 2D domain The method may include mapping to resources, and multi-carrier-modulating data symbols mapped to resources on the second 2D domain for each resource on the second 2D domain.

Description

Modulation and demodulation method and apparatus in a wireless communication system

The present invention relates to a modulation and demodulation technique in a wireless communication system, and more particularly, to a modulation and demodulation technique for efficiently performing modulation and demodulation of a multi-carrier waveform in a wireless communication system.

With the development of information and communication technology, various wireless communication technologies are being developed. Representative wireless communication technologies include long term evolution (LTE) and new radio (NR) defined in 3rd generation partnership project (3GPP) standards. LTE may be one of 4G (4th Generation) wireless communication technologies, and NR may be one of 5G (5th Generation) wireless communication technologies.

For the processing of wireless data that increases rapidly after commercialization of the 4G communication system, a frequency band higher than the frequency band of the 4G communication system (eg, a frequency band of 6 GHz or less) as well as a frequency band of the 4G communication system (eg, Technologies for a 5G communication system that can use a frequency band of 6 GHz or higher) or a later communication system are being studied.

In an embodiment of the communication system, for modulation and demodulation, an orthogonal frequency division multiplexing (OFDM) method or an orthogonal frequency division multiple access (OFDMA) method may be used. The OFDM scheme or OFDMA scheme may have advantages of relatively high frequency efficiency and simple implementation. The OFDM scheme or OFDMA scheme may be characterized in that data symbols are mapped to time-frequency two-dimensional resources and transmitted. The time-frequency two-dimensional resources may have an interval equal to the OFDM symbol interval on the time axis, and may have an interval equal to the mutual subcarrier interval on the frequency axis.

In an ideal channel, data symbols modulated based on the OFDM scheme or OFDMA scheme and transmitted on time-frequency two-dimensional resources may be orthogonal to each other. In practice, the channel through which the symbols are transmitted may not be ideal. For example, the channel may be a delay spread channel, and/or a Doppler spread channel. The channel may be a frequency selective channel, and/or a time selective channel. Orthogonality between data symbols transmitted through a non-ideal channel may not be guaranteed. On the other hand, when a channel on one time-frequency resource through which one data symbol is transmitted has a low channel gain value due to channel degradation such as fading, it may be difficult to successfully detect or decode the corresponding data symbol.

Matters described in this background section are prepared to enhance understanding of the background of the invention, and may include matters that are not already known to those of ordinary skill in the art to which this technology belongs.

With the development of information and communication technology, various wireless communication technologies are being developed. Representative wireless communication technologies include long term evolution (LTE) and new radio (NR) defined in 3rd generation partnership project (3GPP) standards. LTE may be one of 4G (4th Generation) wireless communication technologies, and NR may be one of 5G (5th Generation) wireless communication technologies.

For the processing of wireless data that increases rapidly after commercialization of the 4G communication system, a frequency band higher than the frequency band of the 4G communication system (eg, a frequency band of 6 GHz or less) as well as a frequency band of the 4G communication system (eg, Technologies for a 5G communication system that can use a frequency band of 6 GHz or higher) or a later communication system are being studied.

In an embodiment of the communication system, for modulation and demodulation, an orthogonal frequency division multiplexing (OFDM) method or an orthogonal frequency division multiple access (OFDMA) method may be used. The OFDM scheme or OFDMA scheme may have advantages of relatively high frequency efficiency and simple implementation. The OFDM scheme or OFDMA scheme may be characterized in that data symbols are mapped to time-frequency two-dimensional resources and transmitted. The time-frequency two-dimensional resources may have an interval equal to the OFDM symbol interval on the time axis, and may have an interval equal to the mutual subcarrier interval on the frequency axis.

In an ideal channel, data symbols modulated based on the OFDM scheme or OFDMA scheme and transmitted on time-frequency two-dimensional resources may be orthogonal to each other. In practice, the channel through which the symbols are transmitted may not be ideal. For example, the channel may be a delay spread channel, and/or a Doppler spread channel. The channel may be a frequency selective channel, and/or a time selective channel. Orthogonality between data symbols transmitted through a non-ideal channel may not be guaranteed. On the other hand, when a channel on one time-frequency resource through which one data symbol is transmitted has a low channel gain value due to channel degradation such as fading, it may be difficult to successfully detect or decode the corresponding data symbol.

Matters described in this background section are prepared to enhance understanding of the background of the invention, and may include matters that are not already known to those of ordinary skill in the art to which this technology belongs.

According to an embodiment of the present invention, a method of operating a first communication node in a communication system includes mapping data symbols to be transmitted to a second communication node of the communication system to resources on a first two-dimensional (2D) domain. , preprocessing the data symbols mapped to the resources on the first 2D domain to spread the data symbols on the resources on the second 2D domain, the preprocessed data symbols on the second 2D domain The method may include mapping to resources, and multi-carrier-modulating data symbols mapped to resources on the second 2D domain for each resource on the second 2D domain.

The mapping to the resources on the first 2D domain may include checking information on a plurality of first spreading resource blocks constituting the first 2D domain, and converting the data symbols into the plurality of first spreading resource blocks. It may include a step of mapping each of them.

A first dimension of the first 2D domain may be a delay domain, a second dimension of the first 2D domain may be a Doppler domain, and the plurality of first spreading resource blocks may correspond to delay-Doppler resource blocks.

The mapping to the resources on the second 2D domain may include checking information on a plurality of second spreading resource blocks constituting the second 2D domain, and a plurality of first spreading resources constituting the first 2D domain. The method may include mapping the preprocessed data symbols mapped for each block to each of the plurality of second spreading resource blocks.

A first dimension of the second 2D domain may be a frequency domain, a second dimension of the second 2D domain may be a time domain, and the plurality of second spreading resource blocks may correspond to frequency-time resource blocks.

The operating method of the first communication node includes, before the step of mapping to resources on the first 2D domain, the second communication node and a plurality of spreading resource blocks constituting the first 2D domain and the second 2D domain. The method may further include performing a signaling procedure on size information.

The performing of the signaling procedure may include receiving signaled information on sizes of the plurality of spreading resource blocks from the second communication node that provides a communication service to the first communication node.

The performing of the signaling procedure includes signaling, by the first communication node, information on sizes of the plurality of spreading resource blocks to one or more communication nodes including the second communication node providing a communication service. can do.

The performing of the signaling procedure includes: performing a signaling procedure on information of candidates having sizes of the plurality of spreading resource blocks with the second communication node, and with the second communication node, and the plurality of spreading resources The method may include performing a signaling procedure on information indicating any one of the candidates of the size of blocks.

In a method of operating a first communication node in a communication system in a communication system according to another embodiment of the present invention, the radio signals received from the second communication node of the communication system are multi-carrier for each resource in the first 2D domain. Demapping data symbols mapped to resources on the first 2D domain from resources on the first 2D domain based on a result of the demodulating step, the multicarrier demodulation step, the first 2D domain postprocessing demapped data symbols from resources on a first 2D domain to despread them to resources on a first 2D domain, and converting the post-processed data symbols to resources on a second 2D domain. It may include the step of demapping from

The step of demapping from the resources on the first 2D domain may include checking information on a plurality of first spreading resource blocks constituting the first 2D domain, and mapping for each of the plurality of first spreading resource blocks. demapping data symbols present from the plurality of first spreading resource blocks, wherein a first dimension of the first 2D domain is a frequency domain, and a second dimension of the first 2D domain is a time domain. , the plurality of first spreading resource blocks may correspond to frequency-time resource blocks.

The step of demapping from the resources on the second 2D domain may include checking information of a plurality of second spreading resource blocks constituting the second 2D domain, and the post-processing of the plurality of first spreading resource blocks. and demapping the data symbols mapped for each of the plurality of first spreading resource blocks from the plurality of first spreading resource blocks, wherein a first dimension of the second 2D domain is a delay domain, and a second dimension of the first 2D domain is a delay domain. is a Doppler domain, and the plurality of second spreading resource blocks may correspond to delay-Doppler resource blocks.

The operating method of the first communication node includes, before the step of demodulating the multicarrier, signaling information on the size of the second communication node and a plurality of spreading resource blocks constituting the first 2D domain and the second 2D domain It may further include the step of performing the procedure.

The performing of the signaling procedure may include receiving signaled information on sizes of the plurality of spreading resource blocks from the second communication node that provides a communication service to the first communication node.

The performing of the signaling procedure includes signaling, by the first communication node, information on sizes of the plurality of spreading resource blocks to one or more communication nodes including the second communication node providing a communication service. can do.

The performing of the signaling procedure includes: performing a signaling procedure on information of candidates having sizes of the plurality of spreading resource blocks with the second communication node, and with the second communication node, and the plurality of spreading resources The method may include performing a signaling procedure on information indicating any one of the candidates of the size of blocks.

A method of operating a first communication node includes, after the step of demapping from resources on the first 2D domain, data symbols demapped from resources on the first 2D domain on the first 2D domain. It may include performing channel equalization.

The performing of channel equalization on the first 2D domain may include performing channel estimation on the first 2D domain and performing channel estimation on the first 2D domain on the first 2D domain based on a result of the channel estimation on the first 2D domain. calculating a channel equalization coefficient of , and performing channel equalization on the first 2D domain based on the calculated channel equalization coefficient on the first 2D domain.

The method of operation of the first communication node includes, after the step of demapping from resources on the second 2D domain, for data symbols demapped from resources on the second 2D domain on the second 2D domain. It may include performing channel equalization.

The operating method of the first communication node includes, before the step of demodulating the multicarrier, a terminal capability report related to channel equalization in at least one of the first 2D domain and the second 2D domain, the second communication node It may further include the step of transmitting to.

According to an embodiment of the present invention, information bits in a transport block may be transmitted and received based on a modulation and demodulation operation of a multicarrier waveform based on the spreading of multiple 2D resource blocks. Accordingly, the diversity gain of the channel experienced by each symbol in the codeword can be improved. In addition, interference between data symbols according to multiplexing may be reduced or limited due to channel spreading.

According to an embodiment of the present invention, multi-carrier demodulation and channel equalization may be performed for each 2D resource block in the receiving node. Accordingly, the reception processing delay can be reduced. Here, the channel equalization may be performed based on a linear channel equalization method or a turbo channel equalization method. Accordingly, error rates such as BER, SER, and BLER may be reduced, and reception performance of the receiving node may be improved.

1 is a conceptual diagram illustrating an embodiment of a communication system.
2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.
3 is a block diagram illustrating an embodiment of a communication system including a transmitting node and a receiving communication node.
4 is a block diagram illustrating an embodiment of a modulator of a transmission node in a communication system.
5 is a flowchart illustrating an embodiment of a modulation method in a communication system.
6 is a conceptual diagram for explaining embodiments of a data symbol and reference signal (RS) mapping scheme for resources on a first two-dimensional (2D) domain in a communication system.
7 is a conceptual diagram for explaining an embodiment of a relationship between data symbols, resources on a first 2D domain, and resources on a second 2D domain in a communication system.
8 is a block diagram illustrating an embodiment of a demodulator of a receiving node in a communication system.
9 is a flowchart for explaining an embodiment of a multi-carrier demodulation method in a communication system.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

In embodiments of the present application, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B”. Also, in the embodiments of the present application, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B”.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but it is understood that other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

A communication system to which embodiments according to the present invention are applied will be described. The communication system to which the embodiments according to the present invention are applied is not limited to the contents described below, and the embodiments according to the present invention can be applied to various communication systems. Here, a communication system may be used in the same meaning as a communication network (network).

Throughout the specification, a network is, for example, a wireless Internet such as WiFi (wireless fidelity), a wireless broadband internet (WiBro) or a portable Internet such as a world interoperability for microwave access (WiMax), a global system for mobile communication (GSM). ) or 2G mobile communication networks such as code division multiple access (CDMA), wideband code division multiple access (WCDMA) or 3G mobile networks such as CDMA2000, high speed downlink packet access (HSDPA) or high speed uplink packet access (HSUPA) such as It may include a 3.5G mobile communication network, a 4G mobile communication network such as a long term evolution (LTE) network or an LTE-Advanced network, and a 5G mobile communication network.

Throughout the specification, a terminal is a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, and an access terminal. and the like, and may include all or some functions of a terminal, a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, an access terminal, and the like.

Here, a desktop computer that can communicate with a terminal, a laptop computer, a tablet PC, a wireless phone, a mobile phone, a smart phone, a smart watch (smart watch), smart glass, e-book reader, PMP (portable multimedia player), portable game console, navigation device, digital camera, DMB (digital multimedia broadcasting) player, digital voice Digital audio recorder, digital audio player, digital picture recorder, digital picture player, digital video recorder, digital video player ) can be used.

Throughout the specification, a base station is an access point, a radio access station, a Node B, an advanced nodeB, a base transceiver station, MMR ( It may refer to mobile multihop relay)-BS, and the like, and may include all or some functions of a base station, an access point, a wireless access station, a Node B, an eNodeB, a transceiver base station, and an MMR-BS.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate the overall understanding, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

1 is a conceptual diagram illustrating an embodiment of a communication system.

1, the communication system 100 is a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). A plurality of communication nodes are 4G communication (eg, long term evolution (LTE), LTE-A (advanced)) defined in 3GPP (3rd generation partnership project) standard, 5G communication (eg, NR (new radio)) ) can be supported. 4G communication may be performed in a frequency band of 6 GHz or less, and 5G communication may be performed in a frequency band of 6 GHz or more as well as a frequency band of 6 GHz or less.

For example, a plurality of communication nodes for 4G communication and 5G communication is a CDMA (code division multiple access) based communication protocol, WCDMA (wideband CDMA) based communication protocol, TDMA (time division multiple access) based communication protocol, FDMA (frequency division multiple access) based communication protocol, OFDM (orthogonal frequency division multiplexing) based communication protocol, Filtered OFDM based communication protocol, CP (cyclic prefix)-OFDM based communication protocol, DFT-s-OFDM (discrete) Fourier transform-spread-OFDM) based communication protocol, OFDMA (orthogonal frequency division multiple access) based communication protocol, SC (single carrier)-FDMA based communication protocol, NOMA (Non-orthogonal multiple access), GFDM (generalized frequency) Division multiplexing)-based communication protocol, FBMC (filter bank multi-carrier)-based communication protocol, UFMC (universal filtered multi-carrier)-based communication protocol, SDMA (Space Division Multiple Access)-based communication protocol, etc. can be supported. .

Also, the communication system 100 may further include a core network. When the communication system 100 supports 4G communication, the core network may include a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME), and the like. have. When the communication system 100 supports 5G communication, the core network may include a user plane function (UPF), a session management function (SMF), an access and mobility management function (AMF), and the like.

On the other hand, a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-) constituting the communication system 100 4, 130-5, 130-6) may each have the following structure.

2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , the communication node 200 may include at least one processor 210 , a memory 220 , and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240 , an output interface device 250 , a storage device 260 , and the like. Each of the components included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each of the components included in the communication node 200 may not be connected to the common bus 270 but to the processor 210 through an individual interface or an individual bus. For example, the processor 210 may be connected to at least one of the memory 220 , the transceiver 230 , the input interface device 240 , the output interface device 250 , and the storage device 260 through a dedicated interface. .

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 210 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may be configured as at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may be configured as at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1 , the communication system 100 includes a plurality of base stations 110 - 1 , 110 - 2 , 110 - 3 , 120 - 1 and 120 - 2 , and a plurality of terminals 130 - 1, 130-2, 130-3, 130-4, 130-5, 130-6). base stations 110-1, 110-2, 110-3, 120-1, 120-2 and terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 The comprising communication system 100 may be referred to as an “access network”. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. have. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, 120-2 is a NodeB (NodeB), an advanced NodeB (evolved NodeB), a base transceiver station (BTS), Radio base station (radio base station), radio transceiver (radio transceiver), access point (access point), access node (node), RSU (road side unit), RRH (radio remote head), TP (transmission point), TRP ( transmission and reception ooint), eNB, gNB, and the like.

Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 includes a user equipment (UE), a terminal, an access terminal, and a mobile terminal. Terminal (mobile terminal), station (station), subscriber station (subscriber station), mobile station (mobile station), portable subscriber station (portable subscriber station), node (node), device (device), Internet of Things (IoT) It may be referred to as a device, a mounted device (such as a mounted module/device/terminal or on board device/terminal).

Meanwhile, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul link or a non-ideal backhaul link. , information can be exchanged with each other through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to the corresponding terminals 130-1, 130-2, 130-3, 130 -4, 130-5, 130-6), and the signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) is transmitted to the core network can be sent to

In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits MIMO (eg, single user (SU)-MIMO, multi user (MU)- MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, device to device communication (D2D) (or, ProSe ( proximity services)), and the like. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 is the base station 110-1, 110-2, 110-3, and 120-1. , 120-2) and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be performed. For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO method, and the fourth terminal 130-4 may transmit a signal based on the SU-MIMO method. A signal may be received from the second base station 110 - 2 . Alternatively, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 and the fifth terminal 130-5 based on the MU-MIMO scheme, and the fourth terminal 130-4. and each of the fifth terminals 130 - 5 may receive a signal from the second base station 110 - 2 by the MU-MIMO method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP method, and the fourth The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by the CoMP method. A plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) each of the terminals (130-1, 130-2, 130-3, 130-4) belonging to its own cell coverage , 130-5, 130-6) and the CA method can transmit and receive signals. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 controls D2D between the fourth terminal 130-4 and the fifth terminal 130-5. and each of the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively. .

On the other hand, in general, a transmitter inputs a transport block (TB) composed of information (or message) bits to be transmitted into a channel coding block and undergoes a channel encoding process at a given code rate (or data symbol modulation order). ) and the coding bits corresponding to the modulation and coding scheme (MCS) level related to the channel coding rate) are output. The channel coding block is a cyclic redundancy check (CRC) bit calculation and addition of the transport block, (when the transport block size exceeds a certain size) code block segmentation (ie, CRC bits are added) Splitting a transport block into multiple code blocks), calculating and adding CRC bits for each code block, channel encoding for each code block, rate matching (RM) and HARQ for each code block (CB) ( Hybrid automatic repeat request) processing, bit interleaving, and code block concatenation (ie, concatenating coding bits of a plurality of code blocks) may be all or partly configured. In the above, when the transport block is not divided into a plurality of code blocks, it is unnecessary to calculate and add CRC bits for each code block, and the remaining functional blocks are performed on the transport block itself to which the CRC bit is added, and the last code block concatenation is may be unnecessary. In the case of rate matching, the code rate can be adjusted by performing puncturing and/or shortening and/or repetition on coded bits that are output of channel encoding. . As channel encoding, various channel encoding methods such as turbo code, low density parity check (LDPC) code, and polar code can be applied. The coded bits that are the output of the channel coding block may be input to a modulation/constellation mapper after scrambling (bit-level scrambling), and may output data symbols through a data modulation process.

Hereinafter, each set of data symbols output through a channel encoding process and a data modulation process for each transport block is referred to as a codeword. That is, one transport block and one codeword are regarded as one-to-one correspondence. Additionally, the transmitter may perform the following additional procedure on data symbols (or symbols spread on resources on a second two-dimensional domain (or region) described below) for multi-antenna transmission. The transmitter may map data symbols belonging to the codeword(s) (or symbols spread to resources on the second two-dimensional domain described below) to the layer(s). Accordingly, when a plurality of transport blocks are transmitted, corresponding codewords may be mapped to different layer(s). Data symbols belonging to different codewords (or symbols spread to resources on a second 2D domain described below) may be restricted to be mapped only to different layers. Data symbols mapped to each layer (or symbols spread to resources on a second two-dimensional domain described below) may be spread to each antenna port through multi-antenna preprocessing.

The transmitter converts the output signals into analog signals through a digital-to-analog converter (DAC) after the two-dimensional (partial) spread multicarrier modulation process described below in the baseband, and then passes through the analog/RF terminal to the receiver through the antenna. can be sent to The receiver converts the RF band signal received through the receiving antenna from the transmitter into a digital signal through an analog-to-digital converter (ADC) through the analog/RF stage, and then converts it into a digital signal at the baseband. A spread multicarrier demodulation process may be performed.

The receiver may decode the data symbols detected after the demodulation process through the following process. The detection data symbols may be input to a modulation/constellation demapper to output a log-likelihood ratio (LLR) for the coded bits. After descrambling the LLR of the coded bits output in this way, the information bits of the corresponding transport block and the result of whether the transport block has passed the CRC can be output. . If the CRC is passed for the corresponding transport block, decoding succeeds, otherwise it can be regarded as decoding failure. The channel decoding block is divided/deconcatenated into a plurality of code blocks when a codeword is composed of a plurality of code blocks, bit deinterleaving for each code block, and rate dematching for each code block ( rate dematching) and LLR combining, channel decoding for each code block, CRC check for each code block, code block concatenation/desegmentation (that is, decoded bits for each code block) concatenation), and may undergo transport block CRC verification. When the received codeword is not composed of a plurality of code blocks, code block division is unnecessary and the remaining functional blocks are performed on the codeword itself. CRC check for each code block and code block concatenation are unnecessary, and Whether or not the CRC has passed may be checked from the information bits and CRC bits of the corresponding transport block, which are outputs of decoding.

In the case of downlink (DL) below, the transmitter may be a base station or a repeater or a transmission point (TP) or a transmission and reception point (TRP), and the receiver is a device or a mobile device or a user terminal (user equipment: UE). In the case of uplink (UL), the transmitter may be a terminal or a user terminal, and the transmitter may be a base station or a repeater, or a transmission point or a transmission/reception point. Unless otherwise stated, the transmitter and receiver do not distinguish the link direction. In the case of sidelink (SL), the transmitter and the receiver may be different terminals.

Next, modulation and demodulation methods in a wireless communication system in a wireless communication system will be described. Here, even when a method (eg, transmission or reception of a signal) performed in a first communication node among communication nodes is described, a second communication node corresponding thereto is a method corresponding to the method performed in the first communication node (eg, receiving or transmitting a signal). For example, when the operation of the reception node is described, the corresponding transmission node may perform the operation corresponding to the operation of the reception node. Conversely, when the operation of the transmitting node is described, the corresponding receiving node may perform the operation corresponding to the operation of the transmitting node.

In this specification, in describing a modulation and demodulation method in a wireless communication system, parameters as shown in Table 1 may be used.

On the other hand, the discrete Fourier transform (DFT), inverse DFT (IDFT), Walsh-Hadamard transform (WHT), and inverse WHT (IWHT) referred to in this specification are normalized so that the magnitudes of the input signal and the output signal do not change. 3 is a block diagram for explaining an embodiment of a communication system including a transmitting node and a receiving communication node.

Referring to FIG. 3 , the communication system 300 may include a plurality of communication nodes. Some of the communication nodes of the communication system 300 may operate as transmitting communication nodes that perform a wireless signal transmission operation. The transmitting communication node may also be referred to as a 'transmitting node'. Meanwhile, some of the communication nodes of the communication system 300 may operate as transmission communication nodes that perform a radio signal reception operation. The receiving communication node may be referred to as a 'receiving node'. In one embodiment of the communication system 300 , each of the communication nodes may operate as a transmitting node and/or a receiving node. FIG. 3 can be viewed as showing an embodiment of a communication system 300 including a communication node operating as a transmission node 310 and a communication node operating as a reception node 320 at a specific time point. However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

The transmitting node 310 may modulate a symbol or signal to be transmitted to the receiving node 320 . The transmitting node 310 may transmit a modulated signal through an antenna or an emitter. A signal transmitted from the transmission node 310 may be transmitted through a channel or a medium on a transmission waveform. The receiving node 320 may receive a signal transmitted through a channel or medium through an antenna or a collector. The reception node 320 may restore a desired signal to be transmitted by the transmission node 310 by demodulating the received signal based on the reception waveform. Here, the original signal to be transmitted by the transmitting node 310 to the receiving node 320 may include various types of symbols or signals such as data symbols, pilot symbols, and reference signals. In this specification, embodiments of a method and apparatus for modulation and demodulation in a wireless communication system will be described by taking operations in which the transmitting node 310 and the receiving node 320 mutually transmit and receive an original signal, which is a data symbol, as an example. However, this is only an example for convenience of description and the embodiment of the present invention is not limited thereto. For example, embodiments of the present invention may be equally or similarly applied to an operation of transmitting and receiving various types of original signals such as pilot symbols and reference signals.

Specifically, the communication system 300 includes a transmitting node 310 for transmitting a signal, a receiving node 320 for receiving a signal from the transmitting node 310 and a signal between the transmitting node 310 and the receiving node 320 . It may include a channel 330 through which it can be transmitted. The transmitting node 310 may include an encoder 312 , a modulator 314 , and the like, and the receiving node may include a demodulator 322 , a decoder 324 , and the like. Here, the encoder 312 , the modulator 314 , the demodulator 322 , and the decoder 324 are an encoder 312 , a modulator 314 , and a demodulator 322 , respectively. ) and a decoder 324 .

Each of the transmitting node 310 and the receiving node 320 is a base station (eg, the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 shown in FIG. 1) or a terminal ( For example, it may correspond to the terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 shown in FIG. 1 . When the transmitting node 310 is a base station, the receiving node 320 may be a terminal. Alternatively, when the transmitting node 310 is a terminal, the receiving node 320 may be a base station or another terminal. Each of the transmitting node 310 and the receiving node 320 may be configured the same as or similar to the communication node 200 shown in FIG. 2 .

The transmitting node 310 may perform an encoding process and a modulation process before transmitting the transport block to the receiving node 320 . The encoder 312 may perform an encoding process on the transport block. Specifically, the encoder 312 may encode a transport block into a codeword including a plurality of code blocks. In this case, the encoder 312 may divide the transport block into small blocks. The encoder 312 may configure a block set by grouping the divided blocks into an arbitrary number. The number of blocks may be determined by the channel environment of the communication network, performance information of the transmitting node 310 and the receiving node 320, and the requirements of the application program. The encoder 312 may perform encoding in units of block sets. The encoder 312 may transmit the encoded codeword to the modulator 314 .

The modulator 314 may generate a modulation symbol by modulating the codeword. The modulator 314 may modulate the codeword into symbols using various modulation methods. Modulation may mean converting signal information into an appropriate form, such as strength, displacement, frequency, or phase of a signal (information) in accordance with channel characteristics of a transmission medium. Modulation may be a process of converting a signal containing data into a waveform suitable for a transmission channel.

The transmitting node 310 maps the modulated symbols to time/frequency resources, and a channel 330 formed between the transmitting node 310 and the receiving node 320 for a signal generated based on the mapped symbol. may be transmitted to the receiving node 320 through Specifically, signals propagated through the antenna of the transmitting node 310 may be transmitted to the antenna of the receiving node 320 through the channel 330 . In this case, noise may be generated on the channel.

A signal received through the antenna of the receiving node 320 may be transmitted to the demodulator 322 . The demodulator 322 may demodulate a signal according to a demodulation method determined according to a channel environment. The demodulator 322 may generate a codeword by demodulating the signal, and may transmit the demodulated codeword to the decoder 324 . The decoder 324 receiving the demodulated codeword may decode the codeword to obtain an output transport block.

4 is a block diagram illustrating an embodiment of a modulator of a transmission node in a communication system.

Referring to FIG. 4 , a transmitting node in a communication system may include a modulator 400 . Here, the modulator may be the same as or similar to the modulator 314 of the transmission node 310 described with reference to FIG. 3 . The modulator 400 may receive a codeword generated through a process such as encoding in a transport block or data symbols within the codeword. The modulator 400 of the transmission node may output transmission signals by modulating the input codeword or data symbols within the codeword. In an embodiment of the communication system, the modulator 400 may include components such as a first mapper 410 , a preprocessor 420 , a second mapper 430 , and a multi-carrier modulator 440 . . However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

A first mapper 410 of the modulator 400 may map input data symbols to resources on a first two-dimensional (2D) domain. Next, the preprocessor 420 of the modulator 400 performs pre-processing for spreading (spreading) each data symbol mapped to the resources on the first 2D domain to the resources on the second 2D domain. processing or precoding). Next, the second mapper 430 of the modulator 400 may map the preprocessed data symbols to resources on the second 2D domain. Next, the multicarrier modulator 440 of the modulator 400 may perform multicarrier modulation for each resource on the second 2D domain on the data symbols mapped to the resources on the second 2D domain after preprocessing. have. Here, multi-carrier modulation for each resource in the second 2D domain for data symbols may mean that multi-carrier modulation is performed for each OFDM symbol. Specifically, the multi-carrier modulator 440 may generate transmission signals by modulating data symbols mapped to resources on the second 2D domain after pre-processing into individual waveforms for each corresponding resource on the second 2D domain. . Transmission signals generated by the multi-carrier modulator 440 may be transmitted to a receiving node.

In the modulation process in the modulator 400 , data symbols may be two-dimensionally spread or two-dimensionally partially spread with respect to resources on a 2D domain. Here, '2D partial spread' may mean that data symbols are spread within a specific spreading resource group or spreading resource block on the 2D domain. Here, the specific spreading resource group or spreading resource block may include some resources on the 2D domain or all resources. Hereinafter, in the present specification, a 'resource block' may be an expression referring to a 'spread resource block' or a 'spread resource group'.

A delay-Doppler or Doppler-delay domain as an embodiment of the first 2D domain, and a frequency (or subcarrier)-time (or multicarrier symbol as an embodiment of the second 2D domain) ) (frequency-time or subcarrier-MC symbol) or time (or multi-carrier symbol)-frequency (or multi-carrier) (time-frequency or MC symbol-subcarrier) domain may be considered.

When transmitting with multiple-input and multiple-output (MIMO) or multiple-input and single-output (MISO) using a multiple antenna port, preprocessing for multiple antenna transmission is required. This may be performed between the first mapper 410 and/or the preprocessor 420 and the second mapper 430 . In the former case, the operation of the first mapper 410 may be performed for each antenna port that is the output of preprocessing for multi-antenna transmission. In the latter case, the operations of the first mapper 410 and the preprocessor 420 are performed for each layer that is the input of preprocessing for multi-antenna transmission, and after pre-processing for multi-antenna transmission is performed, the output of pre-processing for multi-antenna transmission The operations of the second mapper 430 and the modulator 440 may be performed for each in-antenna port. A modulation operation in the modulator 400 or a technical feature related to a modulation operation will be described in more detail below with reference to FIG. 5 .

5 is a flowchart illustrating an embodiment of a modulation method in a communication system.

Referring to FIG. 5 , a transmitting node in a communication system may include a modulator. Here, the modulator of the transmitting node may be the same as or similar to the modulator 400 described with reference to FIG. 4 . The modulator may receive a codeword generated through a process such as encoding in a transport block or data symbols within the codeword. The transmitting node may modulate the codeword input to the modulator or data symbols in the codeword through the modulator. In other words, the modulator of the transmission node may modulate the input codeword or data symbols in the codeword to output transmission signals. In an embodiment of the communication system, the modulator may include components such as a first mapper, a preprocessor, a second mapper, and a multi-carrier modulator. However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

The modulation process of data symbols constituting one codeword is as follows. Data symbols in one codeword are mapped to _NG two-dimensional spreading resource blocks (including a case where _NG is 1) on the first two-dimensional domain. In order to spread the data symbols mapped to each two-dimensional spreading resource block on the first two-dimensional domain to resources in each corresponding two-dimensional spreading resource block on the second two-dimensional domain, each spreading resource on the first two-dimensional domain For each block, only preprocessing (as an example of preprocessing, discrete symplectic Fourier transform (DSFT) (or performing discrete Fourier transform (DFT) for the first dimension and inverse DFT (IDFT) for the second dimension)) or this Can be configured to include TX windowing followed by it together, as another example of preprocessing, Walsh-Hadamard transform (WHT) for the first dimension and inverse WHT (IWHT) for the second dimension alone or together It may be configured including transmit windowing following this). Data symbols preprocessed for each spreading resource block in the first 2D domain are mapped to resources in each corresponding spreading resource block in the second 2D domain. Multicarrier modulation may be performed on data symbols spread on resources on the second 2D domain.

The first two-dimensional domain may be defined as a delay-Doppler domain or a Doppler-delay domain or other two-dimensional domain type. Hereinafter, for convenience, a delay-Doppler domain (a first dimension in the first two-dimensional domain corresponds to a delay domain) and the second dimension corresponds to the Doppler domain).

The second two-dimensional domain may be defined as a frequency-time domain or a time-frequency domain or other two-dimensional domain type. Hereinafter, for convenience, a frequency-time domain (a first dimension in the second two-dimensional domain corresponds to a frequency domain) and the second dimension corresponds to the time domain).

Different spreading resource blocks on the first two-dimensional domain may have different independent resource grids. Different spreading resource blocks on the second 2D domain may share a common grid. Each spreading resource block on the first 2D domain may correspond to a different spreading resource block on the second 2D domain. The size of each spreading resource block on the first two-dimensional domain may be the same as the size of each corresponding spreading resource block on the second two-dimensional domain. Spreading resource blocks on the first 2D domain may be given sequential indices, and data symbols may be sequentially mapped in the order of spreading resource block indices. When the spreading resource block size is K , the first K data symbols are sequentially mapped to the 0th spreading resource block, the next K data symbols are sequentially mapped to the next 1st spreading resource block, and the following spreading resource blocks are In this way, the spreading resource block indexes are performed in the same order for . Such a mapping rule may be defined in advance.

When mapping data symbols in each spread resource block on the first 2D domain, it may be mapped first to the delay axis and then to the Doppler axis. Alternatively, you can map to the Doppler axis first and then to the delay axis. Such a mapping rule may be defined in advance or the base station may set a rule to be applied to the terminal.

When the spreading resource block on the first 2D domain is mapped to resources on the second 2D domain, it may be mapped first on the frequency axis and then on the time axis. (This has an advantage that it can have a relatively small processing delay.) Alternatively, when a spreading resource block on a first 2D domain is mapped to resources on a second 2D domain, it is first mapped on the time axis and then on the frequency axis. can be mapped. Such a mapping rule may be defined in advance or the base station may set a rule to be applied to the terminal.

As multi-carrier modulation, modulation such as CP-OFDM, W-OFDM (or PS-OFDM), and F/SBF-OFDM may be applied. The data symbols or the spread data symbols may be multiplexed with reference signals and transmitted in a first two-dimensional domain to a second two-dimensional domain.

Specifically, a codeword or data symbols in the codeword may be input to the modulator of the transmitting node. The modulator may map the data symbols in the codeword to resources on the first 2D domain (S510). The operation according to step S510 may be performed by the first mapper 410 described with reference to FIG. 4 . The modulator may perform preprocessing for spreading data symbols mapped to resources on the first 2D domain to resources on the second 2D domain (S520). The operation according to step S520 may be performed by the preprocessor 420 described with reference to FIG. 4 . The modulator may map the preprocessed data symbols to resources on the second 2D domain (S530). The operation according to step S530 may be performed by the second mapper 430 described with reference to FIG. 4 . The modulator may multi-carrier-modulate data symbols mapped to resources on the second 2D domain for each resource or resource blocks on the second 2D domain. The operation according to step S540 may be performed by the multi-carrier modulator 440 described with reference to FIG. 4 .

Specifically, the modulator may map only data symbols to resources on the first 2D domain, and may further map additional signals other than data symbols to resources on the first 2D domain. For example, one or more reference signals (RS) or one or more symbols corresponding to one or more RSs may be mapped to some of the resources in the first 2D domain instead of data symbols. Alternatively, one or more demodulation reference signals (DMRS) or one or more symbols corresponding to one or more DMRSs may be mapped to some of the resources in the first 2D domain instead of data symbols. Meanwhile, some of the resources on the first 2D domain may be vacated without mapping in consideration of interference between resources on the first 2D domain. Alternatively, a guard resource may be disposed on some of the resources on the first 2D domain. A mapping operation for resources on the first 2D domain according to step S510 will be described in more detail below with reference to FIG. 6 .

6 is a conceptual diagram for explaining embodiments of a data symbol and reference signal (RS) mapping scheme for resources on a first two-dimensional (2D) domain in a communication system.

Referring to FIG. 6 , in an embodiment of a communication system, a first communication node may modulate a signal for transmission to a second communication node. Here, the first communication node may be the same as or similar to the transmission node 310 described with reference to FIG. 3 . The second communication node may be the same as or similar to the receiving node 320 described with reference to FIG. 3 . The first communication node may modulate the codeword output as a result of operation on the transport block by the encoder through the modulator. Here, the modulator may be the same as or similar to the modulator 400 described with reference to FIG. 4 . Here, the modulator of the first communication node may map data symbols constituting the codeword to resources on the first 2D domain in the process of performing the modulation operation. The modulator of the first communication node may map one or more RSs to resources on the first 2D domain in addition to data symbols.

The first example of FIG. 6 may refer to a mapping method in which one RS is mapped to a centrally located resource and data symbols are mapped to the remaining resources. The second example of FIG. 6 may refer to a mapping method in which one RS is mapped to a centrally located resource and eight resources (null resources) surrounding it are not mapped and data symbols are mapped to the remaining resources. The third example of FIG. 6 may refer to a mapping method in which RS is mapped to nine centrally located resources and data symbols are mapped to the remaining resources.

When transmitting symbols mapped or spread to different resource blocks on the second 2D domain (described in detail below), channels experienced within each resource block on the second 2D domain are different, so each resource on the second 2D domain is different. It may be necessary to transmit the reference signal(s) to the resource(s) on the first 2D domain corresponding to each block.

Resources on the first 2D domain that are spread on different resource blocks on the second 2D domain may be separated and despread on the second 2D domain, so that the symbols spread on different resource blocks on the second 2D domain are It may be advantageous to contiguously allocate to resources on 1 2D domain, whereas data symbols transmitted in resources on a first 2D domain that are spread in the same resource block on a second 2D domain are channel spread over the first 2D domain. Because they may interfere with each other, it may be advantageous to allocate them as far apart as possible. For data symbols spread and transmitted in the same resource block on the second 2D domain to one specific receiver, resources on the first 2D domain It may be desirable to map to an interleaved pattern.

7 is a conceptual diagram for explaining an embodiment of a relationship between data symbols, resources on a first 2D domain, and resources on a second 2D domain in a communication system.

7 shows an example in which 12 data symbols in one codeword are mapped to 12 resources on a first 2D domain, and each 4 data symbols are spread into the same resource block on a second 2D domain. have. It can be seen that each of the four data symbols spread into each same resource block on the second 2D domain is mapped to the resource grid on the first 2D domain in an interleaved pattern, respectively. On the other hand, in an embodiment of the communication system, it is considered that symbols spread into different resource blocks on the second 2D domain are distributed and mapped to independently separated grids (ie, three grids) on the first 2D domain. can be

For multiple access of different users, data symbols for different users may be mapped without overlapping by dividing all resources on the first 2D domain. Additionally or alternatively, data symbols for different users may be mapped without overlapping by dividing all resources on the second 2D domain for multiple access of different users. The latter case will be described in detail in the operation part of the second mapper 130 below. In the case of non-orthogonal multiple access, resources on the first 2D domain and/or resources on the second 2D domain may be mapped to different users by overlapping all or part of them.

Referring back to FIG. 5 , the modulator may perform a modulation operation on each codeword. A modulated signal generated based on a modulating operation in the modulator may be represented by a modulated signal matrix S . The modulation signal matrix S may be expressed as Equation (1).

크기를 가질 수 있다. 여기서, 변조 신호 행렬 S의 행의 수인

은 다중반송파(multicarrier, MC) 심볼 당 전체 부반송파의 개수를 의미할 수 있다. 또는,

은 FFT의 크기 또는 주파수 도메인 자원 개수 등을 의미할 수도 있다. 변조 신호 행렬 S의 행의 수인 N은 전송 시간 간격(transmission time interval, TTI) 내의 다중반송파 심볼의 개수, 또는 시간 도메인 자원의 개수를 의미할 수 있다. N_G는 제2 2D 도메인 상의 자원 블록들의 수를 의미할 수 있다. N_G는 1일 수도 있고, 1보다 큰 자연수일 수도 있다. [N_G]는 제2 2D 도메인 상의 자원 블록들의 집합, 또는 자원 블록들로 구성되는 자원 블록들의 집합을 의미할 수 있다.

는 제2 2D 도메인 상의 g번째 자원 블록 내의 자원들에 스프레딩된 후 다중반송파 변조된 신호 행렬을 의미할 수 있다.Referring to Equation 1, the modulation signal matrix S is

can have size. where, the number of rows of the modulated signal matrix S is

may mean the total number of subcarriers per multicarrier (MC) symbol. or,

may mean the size of the FFT or the number of frequency domain resources. N, which is the number of rows of the modulation signal matrix S , may mean the number of multi-carrier symbols in a transmission time interval (TTI) or the number of time domain resources. _NG may mean the number of resource blocks on the second 2D domain. NG may be 1 _or a natural number greater than 1. [ _NG ] may mean a set of resource blocks on the second 2D domain, or a set of resource blocks composed of resource blocks.

may mean a multi-carrier-modulated signal matrix after being spread on resources in the g-th resource block on the second 2D domain.

는 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 매핑된 후 전처리된 심볼들로 구성되는 행렬을 의미할 수 있다. 수학식 1에서

는 '입력 행렬'에 해당할 수 있다.

및

은, 각각 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 매핑된 후 전처리된 심볼들, 또는 전처리된 심볼들로 구성된 행렬

를, 제2 2D 도메인 상의 g번째 자원 블록의 제1 차원 및 제2 차원 상의 자원들에 매핑하는 행렬을 의미할 수 있다. 여기서, 제1 차원은 주파수 도메인을 의미할 수 있다. 제2 차원은 시간 도메인을 의미할 수 있다.In Equation 1,

may mean a matrix composed of preprocessed symbols after being mapped to resources in the g-th resource block on the first 2D domain. in Equation 1

may correspond to an 'input matrix'.

and

, respectively, mapped to resources in the g-th resource block on the first 2D domain and then preprocessed symbols, or a matrix composed of preprocessed symbols

may mean a matrix mapping to resources on the first dimension and the second dimension of the g-th resource block on the second 2D domain. Here, the first dimension may mean a frequency domain. The second dimension may mean a time domain.

는 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 매핑된 후 전처리된 심볼들로 구성된 행렬일 수 있다. 행렬

의 크기는

에 해당할 수 있다. 여기서,

은 제1 2D 도메인 상의 g번째 자원 블록 내 지연 도메인 자원(이하, '지연 자원'이라 칭함)의 개수를 의미할 수 있다.

은 제1 2D 도메인 상의 g번째 자원 블록 내 도플러 도메인 자원(이하, '도플러 자원'이라 칭함)의 개수를 의미할 수 있다.

및/또는

은 제1 2D 도메인 상의 자원 블록들 각각에서 동일한 값을 가질 수도 있고, 상이한 값을 가질 수도 있다. 이하,

및

이 제1 2D 도메인 상의 자원 블록들에서 동일한 값을 가지는 경우를 예시로 하여 통신 시스템에서의 변조 방법의 일 실시예를 설명한다. 그러나 이는 설명의 편의를 위한 예시일 뿐이며, 본 발명의 실시예는 이에 국한되지 않는다.

는

와 같이 정의될 수 있다.Specifically,

may be a matrix composed of pre-processed symbols after being mapped to resources in the g-th resource block on the first 2D domain. procession

the size of

may correspond to here,

may mean the number of delay domain resources (hereinafter, referred to as 'delay resources') in the g-th resource block on the first 2D domain.

may mean the number of Doppler domain resources (hereinafter, referred to as 'Doppler resources') in the g-th resource block on the first 2D domain.

and/or

may have the same value or different values in each of the resource blocks on the first 2D domain. below,

and

An embodiment of a modulation method in a communication system will be described by taking as an example a case in which resource blocks on the first 2D domain have the same value. However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

Is

can be defined as

는 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 매핑된 후 전처리된 심볼들을, 제2 2D 도메인의 g번째 자원 블록의 주파수(frequency) 차원 상의 자원들에 매핑하는 행렬을 의미할 수 있다. 행렬

의 크기는

에 해당할 수 있다. 수학식 1에서,

는 입력 행렬

의 좌측에서 곱해질 수 있다. 여기서, 행렬

가 입력 행렬

의 각 열의

번째 행에 위치한 원소를 출력 행렬의 각 열의

번째 행에 위치한 원소로 매핑하는 경우, 행렬

의 원소들 중

들은 1의 값을 가질 수 있고 그 외의 나머지 원소들은 0의 값을 가질 수 있다.

may mean a matrix that maps preprocessed symbols after being mapped to resources in the g-th resource block in the first 2D domain to resources in the frequency dimension of the g-th resource block in the second 2D domain. procession

the size of

may correspond to In Equation 1,

is the input matrix

can be multiplied on the left side of Here, the matrix

is the input matrix

of each column of

The element located in the first row is assigned to each column of the output matrix.

If mapping to the element located in the first row, the matrix

of the elements of

may have a value of 1, and all other elements may have a value of 0.

는 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 매핑된 후 전처리된 심볼들을, 제2 2D 도메인의 g번째 자원 블록의 시간(time) 차원 상의 자원들에 매핑하는 행렬을 의미할 수 있다. 행렬

의 크기는

에 해당할 수 있다. 수학식 1에서,

는 입력 행렬

의 우측에서 곱해질 수 있다. 여기서, 행렬

가 입력 행렬

의 각 행의

번째 행에 위치한 원소를 출력 행렬의 각 열의

번째 열에 위치한 원소로 매핑하는 경우, 행렬

의 원소들 중

들은 1의 값을 가질 수 있고 그 외의 나머지 원소들은 0의 값을 가질 수 있다.

may mean a matrix that maps preprocessed symbols after being mapped to resources in the g-th resource block in the first 2D domain to resources in the time dimension of the g-th resource block in the second 2D domain. procession

the size of

may correspond to In Equation 1,

is the input matrix

can be multiplied on the right side of Here, the matrix

is the input matrix

of each row of

The element located in the first row is assigned to each column of the output matrix.

If mapping to the element located in the second column, the matrix

of the elements of

may have a value of 1, and all other elements may have a value of 0.

는 크기가

인 송신 펄스 성형 행렬을 의미할 수 있다.

에 의한 송신 펄스 성형 기능은, CP(cyclic prefix) 삽입 기능, 및/또는 오버샘플링 기능을 포함할 수도 있다.

에 의한 송신 펄스 성형 기능이 CP 삽입 기능 및/또는 오버샘플링 기능을 포함할 경우,

일 수 있다.

에 의한 송신 펄스 성형 기능이 CP 삽입 기능을 포함할 경우, 삽입되는 CP의 길이는

일 수 있다. 이를테면,

에 의한 송신 펄스 성형 기능이 CP 삽입 기능을 포함하고 사각 펄스가 적용될 경우,

는 수학식 2와 같이 표현될 수 있다.in Equation 1

is the size

may mean a transmit pulse shaping matrix.

The transmit pulse shaping function by ? may include a cyclic prefix (CP) insertion function, and/or an oversampling function.

If the transmit pulse shaping function by

can be

When the transmission pulse shaping function by CP includes the CP insertion function, the length of the inserted CP is

can be for example,

When the transmit pulse shaping function by CP includes the CP insertion function and a square pulse is applied,

can be expressed as Equation (2).

는 열벡터, 또는 행렬을 구성하는 각각의 열벡터에 대한 M-포인트(point) IDFT(inverse discrete Fourier transform) 행렬을 의미할 수 있다.in Equation 1

may mean a column vector or an M-point inverse discrete Fourier transform (IDFT) matrix for each column vector constituting the matrix.

는, 제2 2D 도메인 상의 각 자원 블록 내 자원들에 매핑 및 전처리된 심볼들이, 제2 2D 도메인 상의 각각의 대응되는 자원 블록 내 자원들에 매핑되는 것을 의미할 수 있다. 수학식 1에서

및

가 곱해지는 것은, 제2 2D 도메인 상의 자원 블록 내 자원들에 매핑된 심볼들이 공통으로 다중반송파 변조되는 것을 의미할 수 있다. 다르게 표현하면,

및

가 곱해지는 것은, 제2 2D 도메인 상의 자원 블록 내 자원들에 매핑된 심볼들에 대해 IFFT(또는 IDFT) 및 송신 펄스 성형이 수행되는 것을 의미할 수 있다.in Equation 1

may mean that symbols mapped and preprocessed to resources in each resource block on the second 2D domain are mapped to resources in each corresponding resource block on the second 2D domain. in Equation 1

and

Multiplied by may mean that symbols mapped to resources in a resource block on the second 2D domain are commonly multi-carrier-modulated. In other words,

and

Multiplying by may mean that IFFT (or IDFT) and transmission pulse shaping are performed on symbols mapped to resources in a resource block on the second 2D domain.

The modulation signal matrix S may be vectorized and expressed as a vector s as shown in Equation (3).

The modulation signal vector s in which the modulation signal matrix S is vectorized may be expressed as in Equation (4).

는 변조부에 입력되는 코드워드에 대응될 수 있다. 구체적으로,

는 코드워드 벡터 x를 구성하는 각각의 부벡터들 중 제1 2D 도메인 상의 g번째 자원 블록 내의 자원들에 매핑되는 데이터 심볼들에 대응되는 부벡터를 의미할 수 있다. 한편, 수학식 4에서

는 각각의 대각 부행렬이

로 구성된 블록 대각 행렬을 의미할 수 있다. 이를테면,

는 수학식 5와 같이 표현될 수 있다.In Equation 4,

may correspond to the codeword input to the modulator. Specifically,

may mean a subvector corresponding to data symbols mapped to resources in the g-th resource block on the first 2D domain among respective subvectors constituting the codeword vector x . On the other hand, in Equation 4

is each diagonal submatrix

It may mean a block diagonal matrix composed of . for example,

can be expressed as in Equation 5.

는, 변조부에 입력되는 코드워드 벡터 x와 변조 신호 벡터 s 간의 관계를 나타내는 것으로 볼 수 있다. 다르게 표현하면,

는, 변조부가 입력된 코드워드 벡터 x에 대한 다중반송파 변조를 통하여 변조 신호 벡터 s를 획득하기 위해서 수행하는 모든 연산들을 하나로 묶어서 표현한 항으로 볼 수 있다. 더불어,

를 구성하는

각각은, 코드워드 x를 구성하는

각각을 변조하기 위하여 수행하는 모든 연산들을 하나로 묶어서 표현한 항으로 볼 수 있다.in other words,

can be seen as representing the relationship between the codeword vector x input to the modulator and the modulated signal vector s . In other words,

can be viewed as a term expressing all operations performed by the modulator to obtain a modulated signal vector s through multi-carrier modulation on the input codeword vector x . together,

to make up

Each constituting codeword x

All operations performed to modulate each can be viewed as a term expressed by grouping them together.

Steps ( S510 to S550 ) or functional blocks corresponding to each step constituting the modulation process performed by the modulator are expressed in the form of a matrix operation or a vector operation such as Equations 1 to 5 . However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto. For example, each function of the modulation process performed by the modulator may be implemented as an operation method other than a matrix operation or a vector operation. Matrix operations or vector operations, such as Equations 1 to 5, can be viewed as simple mathematical expressions of effects due to functions between input and output of respective functional blocks. For example, a product with a DFT matrix may be treated as an FFT, and a product with an IDFT matrix may be treated as an IFFT. The multiplication with the transmit pulse shaping matrix G _T may be performed as multiplying time samples of the modulated signal obtained via FFT or IFFT with respective corresponding coefficients of the pulse. When the function of the transmit pulse shaping matrix includes CP insertion and/or oversampling, transmit pulse shaping may be performed by iteratively expanding each time sample. The resource mapping operation may be processed by indexing or mapping rather than matrix operation.

8 is a block diagram illustrating an embodiment of a demodulator of a receiving node in a communication system.

Referring to FIG. 8 , a receiving node in a communication system may include a demodulator 800 . Here, the demodulator may be the same as or similar to the demodulator 322 of the receiving node 310 described with reference to FIG. 3 . The demodulator 800 may receive information on reception signals received through a wireless channel of a modulated and transmitted wireless signal from a transmission node of a communication system. The demodulator 800 may output demodulated data symbols by modulating the received signals received through a wireless channel. The demodulated data symbols may constitute a demodulation codeword that is a result of restoration of a codeword to be transmitted by the transmitting node. In an embodiment of the communication system, the demodulator 800 may include components such as a multicarrier demodulator 810 , a first demapper 820 , a postprocessor 840 , and a second demapper 850 . can The demodulator 800 may further include a first channel equalizer 830 and a second channel equalizer 860 . However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

The multicarrier demodulator 810 may receive information on received signals received through a wireless channel. The multi-carrier demodulation unit 810 may perform multi-carrier demodulation on the received signals for each resource in the second 2D domain. Here, multi-carrier demodulation for each resource in the second 2D domain for the received signals may mean that multi-carrier demodulation is performed for each OFDM symbol. The multicarrier demodulator 810 may output information on the multicarrier demodulated signals. It can be seen that the multicarrier demodulated signals output from the multicarrier demodulator 810 are mapped to resources in a total of _NG resource blocks on the second 2D domain.

Signals output from the multicarrier demodulator 810 may be input to the first demapper 820 . The first demapper 820 may perform demapping on a demodulated signal mapped to resources in a total of _NG resource blocks on the second 2D domain. Demapped signals may be input to the signal post-processing unit 840 . Alternatively, the demapping signals may be input to the post-processing unit 840 after performing a channel equalization operation in the first channel equalizer 830 .

In the post-processing unit 840, a post-processing operation may be performed for each resource block on signals demapping from a total of _NG resource blocks in the second 2D domain, or signals that have undergone channel equalization operation after demapping. . Signals that have undergone the post-processing operation in the post-processing unit 840 may be considered to be the same as or similar to a state mapped to resource blocks on the first 2D domain. Signals that have undergone a post-processing operation in the post-processing unit 840 may be input to the second demapper 850 .

The second demapper 850 may perform demapping on signals mapped to respective resource blocks in the first 2D domain. The second demapper 850 may output demapped data symbols from resource blocks on the first 2D domain as a result of the demapping operation. The data symbols output from the second demapper 850 may be output from the demodulator 800 as a result of all demodulation operations performed by the demodulator 800 . Alternatively, the data symbols output from the second demapper 850 may be output from the demodulator 800 after performing a channel equalization operation in the second channel equalizer 860 .

The receiving node may obtain a codeword based on the data symbols output from the demodulator 800 . The obtained codeword may be regarded as corresponding to a codeword generated based on information such as data to be transmitted by the transmitting node. A demodulation operation in the demodulation unit 800 or a technical feature related to a demodulation operation will be described in more detail below with reference to FIG. 9 .

9 is a flowchart for explaining an embodiment of a multi-carrier demodulation method in a communication system.

Referring to FIG. 9 , a receiving node in a communication system may include a demodulator. Here, the demodulator of the receiving node may be the same as or similar to the demodulator 800 described with reference to FIG. 8 . The demodulator may receive radio signal information received through a radio channel. The demodulator may perform a demodulation operation based on the inputted radio signal information. In other words, the demodulator may output data symbols by demodulating the radio signal received by the receiving node. In an embodiment of the communication system, the demodulator may include components such as a multi-carrier demodulator, a first demapper, a post-processing unit, and a second demapper. In an embodiment of the communication system, the demodulator may further include components such as a first channel equalizer, a second channel equalizer, and the like. However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto.

In order to demodulate the received signal, it may be necessary to adjust the time and frequency synchronization between the transmitter and the receiver to a certain level or more. In addition, the process of synchronizing a level with a mini-slot and/or a half-slot and/or a slot and/or a frame and/or a superframe may be needed In the present specification, it is assumed that such synchronization is well matched through a synchronization process before the demodulation operation.

Information of a radio signal received through a radio channel may be input to the demodulator of the receiving node. Here, the radio channel may be a time-variant or time varying channel. Alternatively, it may be a non-time-varying (or static) channel. The wireless channel may be a multipath channel. Alternatively, the radio channel may be a single path channel. The time-varying channel may mean a channel that may 'change with time'. A time-varying channel may include a non-time-varying channel as a special part. Meanwhile, the multi-path channel may mean 'a channel including one or more paths'. A multipath channel may include a single path channel as a special part. Hereinafter, the 'time-varying multi-path channel' may be an expression including a case in which the channel is a non-time-varying channel or a single-path channel, unless otherwise defined.

A received signal received through a wireless channel may be expressed as Equation (6).

은 N개의 다중반송파 심볼들 중 n번째 다중반송파 심볼에 대한 수신 신호 벡터를 의미할 수 있다. N개의 수신 신호 벡터들은 수신 신호 행렬

을 구성할 수 있다.

은 무선 채널의 정보를 나타내는 행렬일 수 있다. 여기서,

은 시변 다중경로 채널의 정보가 반영된 선형 시변 콘볼루션 행렬에 해당할 수 있다. 시변 채널에서는, 채널의 정보를 나타내는 논-제로(non-zero) 대각 성분들이 일정한 값을 가지지 않을 수 있다.

이라 할 때,

은

의 크기를 가질 수 있다.

는, 첫 번째 지연 인덱스가 1인 경우를 기준으로, 최대 지연 길이 인덱스를 의미할 수 있다.

는 송신 노드에서 송신된 무선 신호의 정보에 해당할 수 있다.

=

는

의 n번째 대각 성분을 의미할 수 있다.Equation 6 may mean information on each of N multi-carrier symbols in one TTI. Each symbol constituting the multi-carrier may be assumed to be sufficiently spaced apart so that inter-symbol interference (ISI) does not occur. n may mean an index of each multicarrier symbol, and may have a value from 1 to N.

may mean a received signal vector for the nth multicarrier symbol among the N multicarrier symbols. The N received signal vectors are the received signal matrix

can be configured.

may be a matrix indicating radio channel information. here,

may correspond to a linear time-varying convolution matrix in which information of a time-varying multipath channel is reflected. In a time-varying channel, non-zero diagonal components representing channel information may not have a constant value.

when saying,

silver

can have the size of

, may mean a maximum delay length index based on a case in which the first delay index is 1.

may correspond to information of a radio signal transmitted from the transmitting node.

=

Is

may mean the nth diagonal component of .

은 n번째 다중반송파 심볼에서의 잡음 벡터에 해당할 수 있다. 이를테면, 무선 채널에서의 전송 과정에서 발생하는 잡음이 백색 가우시안 잡음일 경우,

은

의 통계성을 가질 수 있다.

may correspond to the noise vector in the nth multicarrier symbol. For example, if the noise generated during the transmission process in the wireless channel is white Gaussian noise,

silver

can have a statistic of

The demodulator may perform multi-carrier demodulation on a signal received through multi-carrier symbols (S910). The demodulator may perform a multi-carrier demodulation operation on the received signal in the second 2D domain. The multicarrier demodulation operation in step S910 may be performed by the multicarrier demodulator 810 described with reference to FIG. 8 . The multi-carrier demodulation operation in step S910 may correspond to the inverse operation of the multi-carrier modulation operation according to the step S540 described with reference to FIG. 5 . The demodulator may perform a multicarrier demodulation operation according to a method such as CP-OFDM, W-OFDM (or PS-OFDM), or F/SBF-OFDM.

Through the multicarrier demodulation operation in step S910, data symbols mapped to resources in a total of _NG resource blocks on the second 2D domain may be obtained. The demodulator may demap the multicarrier demodulated data symbols from resources on the second 2D domain (S920). The demapping operation performed in step S920 may be performed by the first demapper 820 described with reference to FIG. 8 . The demapping operation performed in step S920 may correspond to the reverse operation of the mapping operation performed in step S530 described with reference to FIG. 5 .

로 표현될 수 있다. Signals or data symbols obtained through steps S910 and S920 are the matrix as shown in Equation (7).

can be expressed as

은, 수학식 8과 같이 벡터의 형태로 표현될 수도 있다.expressed as Equation 7

may be expressed in the form of a vector as in Equation (8).

는 크기가

인 수신 펄스 성형 행렬을 의미할 수 있다.

는 도 5를 참조하여 설명한 송신 펄스 성형 행렬

에 대응될 수 있다.

에 의한 수신 펄스 성형 기능은, CP 제거 기능 및/또는 다운샘플링 기능을 포함할 수 있다. 이를테면, 수신 펄스 성형 기능은 CP를 제거하는 기능을 포함할 수 있다. 수신 펄스 성형 기능은 사각 펄스를 적용함에 있어서, 채널 지연에 의해 지연되어 수신된 샘플들을 제거하는 기능을 포함할 수 있다. 수신 펄스 성형 기능에 따라서, 길이가

인 CP가 제거되고 채널 지연에 의해 지연되어 수신된 마지막

개의 시간 샘플들이 제거되며 사각 펄스가 적용되는 경우,

는 수학식 9와 같이 표현될 수 있다.In Equations 7 and 8,

is the size

may mean a receive pulse shaping matrix.

is the transmission pulse shaping matrix described with reference to FIG. 5

can correspond to

The reception pulse shaping function by , may include a CP removal function and/or a downsampling function. For example, the receive pulse shaping function may include a function to remove the CP. The reception pulse shaping function may include a function of removing samples received delayed by a channel delay in applying a square pulse. Depending on the receive pulse shaping function, the length

The last received CP is removed and delayed by the channel delay.

If time samples are removed and a square pulse is applied,

can be expressed as in Equation (9).

The demodulator may perform a second 2D domain channel estimation for data symbols demapped from resources on the second 2D domain through step S920 and a channel equalization operation thereof (S930). The channel estimation and channel equalization operations performed in step S930 may be performed by the first channel equalizer 830 described with reference to FIG. 8 . Here, the operation according to step S930 may be selectively performed. For example, the demodulator may perform a post-processing operation for despreading data symbols demapped from resources on the second 2D domain in step S920 ( S940 ). Hereinafter, an embodiment of a multi-carrier demodulation method in a communication system will be described by taking the case in which the demodulator performs step S940 without performing step S930 as an example. An embodiment in which the demodulator performs step S930 will be described later.

The demodulator performs multicarrier demodulation, demapping, and (if necessary) channel equalization on the second 2D domain on the second 2D domain, and then receives the result as an input to spread a total of _NG each spread on the first 2D domain. Post-processing can be performed for each resource group. For example, post-processing can be performed with either receive windowing and subsequent inverse DSFT (IDSFT) (or perform IDFT for the first dimension and DFT for the second dimension) or only inverse DSFT (IDSFT) without receive windowing. can be configured. As another example, the post-processing may be composed of only the IWHT for the first dimension and the WHT for the second dimension without receiving windowing and the following IWHT for the first dimension and the WHT for the second dimension or receiving windowing. Next, demapping may be performed from resources in each spreading resource block on the first two-dimensional domain.

The demodulator may perform a post-processing operation on data symbols demapped from a total of _NG resource blocks in the second 2D domain for each resource block (S940). The post-processing operation in step S940 may be performed by the post-processing unit 840 described with reference to FIG. 8 . The post-processing operation in step S940 may correspond to the reverse operation of the pre-processing operation in step S520 described with reference to FIG. 5 .

The data symbols that have undergone the post-processing operation in step S940 may be considered to be the same as or similar to a state mapped to resource blocks on the first 2D domain. The demodulator may demap the post-processing data symbols from resources on the first 2D domain (S950). The demapping operation in step S950 may be performed by the second demapper 850 described with reference to FIG. 8 . The demapping operation in step S950 may correspond to the reverse operation of the mapping operation in step S510 described with reference to FIG. 5 .

로 표현될 수 있다. Signals or data symbols obtained through steps S910 and S920 are the matrix as shown in Equation (10).

can be expressed as

는 복조 신호 행렬에 해당할 수 있다. 복조 신호 행렬

는

의 크기를 가질 수 있다.

및

은, 각각 제1 2D 도메인 상의 g번째 자원 블록을 위한 제1 차원 및 제2 차원 상에서의 수신 윈도잉(RX windowing) 행렬을 의미할 수 있다. 제1 차원은 지연 도메인을 의미할 수 있다. 제2 차원은 도플러 도메인을 의미할 수 있다. 구체적으로,

및

는 대각행렬일 수 있다. 대각 행렬인

를 구성하는 대각성분들 각각은, 제1 2D 도메인의 제1 차원 상에서의 수신 윈도우 계수에 해당할 수 있다. 제1 2D 도메인의 제2 차원 상에서 수신 윈도우의 길이는

일 수 있으며,

의 크기는

일 수 있다. 대각 행렬인

를 구성하는 대각성분들 각각은, 제1 2D 도메인의 제2 차원 상에서의 각 수신 윈도우 계수에 해당할 수 있다. 여기서, 제1 2D 도메인의 제2 차원 상에서 수신 윈도우의 길이는

일 수 있으며,

의 크기는

일 수 있다.In Equation 10,

may correspond to a demodulation signal matrix. demodulation signal matrix

Is

can have the size of

and

may mean a reception windowing matrix in the first dimension and the second dimension for the g-th resource block in the first 2D domain, respectively. The first dimension may mean a delay domain. The second dimension may refer to a Doppler domain. Specifically,

and

may be a diagonal matrix. diagonal matrix

Each of the diagonal components constituting ? may correspond to a reception window coefficient in the first dimension of the first 2D domain. The length of the receiving window in the second dimension of the first 2D domain is

can be,

the size of

can be diagonal matrix

Each of the diagonal components constituting ? may correspond to each reception window coefficient in the second dimension of the first 2D domain. Here, the length of the reception window in the second dimension of the first 2D domain is

can be,

the size of

can be

의 크기는

에 해당할 수 있다. 수학식 1에서,

는 입력 행렬

의 좌측에서 곱해질 수 있다. 여기서, 행렬

가 입력 행렬

의 각 열의

번째 행에 위치한 원소를 출력 행렬의 각 열의

번째 행에 위치한 원소로 매핑하는 경우, 행렬

의 원소들 중

들은 1의 값을 가질 수 있고 그 외의 나머지 원소들은 0의 값을 가질 수 있다.It may mean a matrix that maps preprocessed symbols after being mapped to resources in the g-th resource block of the second 2D domain to resources in the frequency dimension of the g-th resource block of the second 2D domain. procession

the size of

may correspond to In Equation 1,

is the input matrix

can be multiplied on the left side of Here, the matrix

is the input matrix

of each column of

The element located in the first row is assigned to each column of the output matrix.

If mapping to the element located in the first row, the matrix

of the elements of

may have a value of 1, and all other elements may have a value of 0.

은, 수학식 11 및/또는 수학식 12와 같이 벡터의 형태로 표현될 수도 있다.expressed as Equation 10

may be expressed in the form of a vector as in Equation 11 and/or Equation 12.

은, 수신 신호의 벡터 vec(R)을 복조하기 위하여 수행하는 모든 연산들을 하나로 묶어서 표현한 항으로 볼 수 있다.

은 수학식 13과 같이 정의될 수 있다.In Equation 12,

can be viewed as a term expressing all operations performed to demodulate the vector vec( R ) of the received signal by grouping them together.

can be defined as in Equation 13.

The demodulator may obtain demapped data symbols from resources on the first 2D domain by performing steps S940 and S950. The demodulator may perform a first 2D domain channel estimation for data symbols demapped from resources on the first 2D domain, and a channel equalization operation thereof (S960). The channel estimation and channel equalization operations performed in step S960 may be performed by the second channel equalizer 860 described with reference to FIG. 8 . Here, the operation according to step S960 may be selectively performed. For example, the demodulator may output data symbols demapped from resources on the first 2D domain through steps S940 and S950 as a result of a demodulation operation in the demodulator ( S970 ). Hereinafter, an embodiment of a multi-carrier demodulation method in a communication system will be described by taking the case in which the demodulator performs step S970 without performing step S960 as an example. An embodiment in which the demodulator performs step S960 will be described later.

와 같이 제1 2D 도메인 상의 자원들로부터 디매핑된 데이터 심볼들을, 복조부에서의 복조 동작의 결과물로서 출력할 수 있다(S970). 수신 노드는 S970 단계에서 출력되는 데이터 심볼들에 기초하여 코드워드를 획득할 수 있다. 획득된 코드워드는, 송신 노드에서 송신하고자 한 데이터 등의 정보에 기초하여 생성되었던 코드워드에 대응되는 것으로 볼 수 있다. The demodulator is a demodulation signal matrix

Demapped data symbols from resources on the first 2D domain as shown in FIG. 1 may be output as a result of a demodulation operation in the demodulator (S970). The receiving node may obtain a codeword based on the data symbols output in step S970. The obtained codeword may be regarded as corresponding to a codeword generated based on information such as data to be transmitted by the transmitting node.

[Linear Channel Equalization on Second 2D Domain]

Hereinafter, a first embodiment of the channel equalization operation on the second 2D domain according to step S930 will be described. In an embodiment of the communication system, the demodulator may perform a channel equalization operation on the second 2D domain for data symbols demapped from resources on the second 2D domain in step S920 ( S930 ). Here, the channel equalization operation according to step S930 may correspond to a linear channel equalization operation or a 1-tap channel equalization operation.

를 획득할 수 있다. 복조부는 S930 단계에서 행렬

에 대한 채널 등화를 수행할 수 있다. 채널 등화를 거친 출력 행렬

는 수학식 14와 같이 표현될 수 있다.Specifically, through steps S910 and S920, the demodulator demodulates the multicarrier for the g-th resource block on the second 2D domain and demapped the signal matrix.

can be obtained. The demodulator is a matrix in step S930.

Channel equalization may be performed for . Output matrix after channel equalization

can be expressed as in Equation 14.

는 S930 단계에 따른 채널 등화 연산에 대응되는 제1 채널 등화 행렬일 수 있다. 연산자 '

'는, 두 행렬의 동일한 행 및 열에 위치한 원소들 간의 곱 연산을 의미할 수 있다.

는

및

의 동일한 행 및 열에 위치한 원소들 간의 곱연산을 통하여 획득되는 행렬일 수 있다.

는 S930 단계에 따른 채널 등화 동작의 결과물에 해당하는 출력 행렬일 수 있다. 제2 2D 도메인 상의 채널 등화 동작의 제1 실시예에서, 제1 채널 등화 행렬

은 수학식 15 또는 수학식 16과 같이 정의될 수 있다.In Equation 14,

may be the first channel equalization matrix corresponding to the channel equalization operation according to step S930. Operator '

' may mean a multiplication operation between elements located in the same row and column of two matrices.

Is

and

It may be a matrix obtained through a multiplication operation between elements located in the same row and column of .

may be an output matrix corresponding to the result of the channel equalization operation according to step S930. In a first embodiment of a channel equalization operation on a second 2D domain, a first channel equalization matrix

may be defined as Equation 15 or Equation 16.

는 행렬의 각 원소들에 역수를 취하는 연산을 의미할 수 있다. 수학식 16에서,

는 행렬의 각 원소들에 대한 복소수 켤레(complex-conjugate)를 취하는 연산을 의미할 수 있다.Equation 15 can be viewed as representing the definition of the first channel equalization matrix according to the 1-tap zero forcing (ZF) equalization method. Equation 16 can be viewed as representing the definition of the first channel equalization matrix according to the 1-tap minimum mean squared error (MMSE) equalization method. In Equation 15 and Equation 16,

may mean an operation of taking the reciprocal of each element of the matrix. In Equation 16,

may mean an operation that takes a complex-conjugate for each element of a matrix.

는 제1 채널 추정 정보 행렬에 해당할 수 있다. 제1 채널 추정 정보 행렬

는 수학식 17과 같이 정의될 수 있다.In Equation 15 and Equation 16,

may correspond to the first channel estimation information matrix. first channel estimation information matrix

can be defined as in Equation 17.

'는 입력 벡터

를

행렬로 변환시키는 연산을 의미할 수 있다. 수학식 16에서

일 수 있고,

일 수 있다. 여기서,

은 잡음의 분산(평균 전력)으로, 실제적으로 이에 대한 추정치가 사용될 수 있다.In Equation 17, '

' is the input vector

cast

It may mean an operation for converting into a matrix. in Equation 16

can be,

can be here,

is the variance of the noise (average power), and in practice an estimate for it can be used.

Ideal channel estimation information used for channel equalization may be defined as in Equation (18).

를 획득할 수 있다. 이를테면, 복조기는 제2 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여, 자원 블록 별 채널 추정 정보

를 획득할 수 있다. 또는, 복조부는 제1 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여 채널 추정을 수행할 수 있고, 수행된 채널 추정 결과를 제2 2D 도메인 상의 채널 추정 정보

로 변환할 수도 있다. 이를테면, 수학식 19와 동일 또는 유사할 수 있다.Meanwhile, in an actual communication system, a demodulator uses channel estimation information based on actual measurement information for a predetermined reference signal.

can be obtained. For example, the demodulator determines channel estimation information for each resource block based on one or more reference signals allocated to one or more resources in each resource block in the second 2D domain.

can be obtained. Alternatively, the demodulator may perform channel estimation based on one or more reference signals allocated to one or more resources in each resource block on the first 2D domain, and use the channel estimation result as channel estimation information on the second 2D domain.

can also be converted to For example, it may be the same as or similar to Equation 19.

는 제1 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여 획득된 채널 추정 정보에 해당할 수 있다. 즉, 수학식 19에 따르면, 제1 2D 도메인 상에서의 측정에 의해 획득된 자원 블록 별 채널 추정 정보

가 제2 2D 도메인 상에서의 자원 블록 별 채널 추정 정보

로 변환될 수 있다. 또는, 복조부는 제1 및 제2 2D 도메인 상의 자원들에 할당된 기준 신호들을 함께 이용하여 채널 추정 정보를 획득할 수도 있다.In Equation 19,

may correspond to channel estimation information obtained based on one or more reference signals allocated to one or more resources in each resource block on the first 2D domain. That is, according to Equation 19, channel estimation information for each resource block obtained by measurement in the first 2D domain

Channel estimation information for each resource block in the second 2D domain

can be converted to Alternatively, the demodulator may acquire channel estimation information by using reference signals allocated to resources on the first and second 2D domains together.

는 S940 단계 및 그 이후의 단계들에서 행렬

를 대체할 수 있다. 제2 2D 도메인 상에서의 채널 등화를 거친 출력 행렬

에 기초하여, S940 단계에 따른 후처리 동작 및 S950 단계에 따른 디매핑 동작이 수행될 수 있다. 제2 2D 도메인 상에서의 채널 등화를 거친 출력 행렬

에 기초하여 수행된 후처리 및 디매핑의 결과로서 데이터 심볼들이 획득될 수 있다. 여기서, 각 데이터 심볼들의 부호화된 비트들에 대한 LLR(log-likelihood ratio)이, 수학식 20과 같이 계산될 수 있다.In step S930, the demodulator may perform a channel equalization operation on the multicarrier demodulation and demapping signal for each resource block on the second 2D domain based on the first embodiment of the channel equalization operation on the second 2D domain. . In this case, the output matrix subjected to channel equalization in the second 2D domain

is a matrix in step S940 and subsequent steps

can be substituted for Output matrix subjected to channel equalization in the second 2D domain

Based on , a post-processing operation according to step S940 and a demapping operation according to operation S950 may be performed. Output matrix subjected to channel equalization in the second 2D domain

Data symbols may be obtained as a result of post-processing and demapping performed based on . Here, a log-likelihood ratio (LLR) for the coded bits of each data symbol may be calculated as in Equation 20.

에서,

일 수 있다.

은 제2 2D 도메인 상에서의 채널 등화를 거친 데이터 심볼

를 구성하는 j번째 비트에 대한 LLR을 의미할 수 있다. 수학식 20에서,

는 i번째 변조 알파벳에 매핑되는 j번째 비트를 의미할 수 있다. 수학식 20에서,

는 Q-ary 데이터 심볼 변조에 대한 변조 알파벳 집합을 의미할 수 있다.

는 벡터

의 k번째 원소일 수 있고,

는 행렬

를 벡터화 시킨 벡터(즉,

)에 해당할 수 있다. 그리고 행렬

는 수학식 10과 같은 복조 신호 행렬에서

가

로 대체된 복조 신호 행렬을 의미할 수 있다. 마찬가지로,

는, 수학식 11과 같은 복조 신호 벡터에서

가

로 대체된 복조 신호 벡터를 의미할 수 있다.

는 행렬

의 대각 성분들을 의미할 수 있다. of Equation 20

at,

can be

is a data symbol that has undergone channel equalization in the second 2D domain

It may mean an LLR for the j-th bit constituting . In Equation 20,

may mean the j-th bit mapped to the i-th modulation alphabet. In Equation 20,

may mean a modulation alphabet set for Q-ary data symbol modulation.

is vector

may be the kth element of

is the matrix

vectorized vector (i.e.,

) may be applicable. and the matrix

is in the demodulation signal matrix as in Equation 10.

go

It may mean a demodulation signal matrix replaced with . Likewise,

In the demodulated signal vector as in Equation 11,

go

may mean a demodulated signal vector replaced by .

is the matrix

may mean the diagonal components of .

)의 계산에 있어서 필요한 제1 2D 도메인 상의 유효 채널의 정보는 다양한 방법으로 획득될 수 있다.LLR value according to Equation 20 (

), information of an effective channel on the first 2D domain required for calculation of ) may be obtained in various ways.

Method 1) When the demodulator performs channel estimation using reference signals allocated to resources on the second 2D domain, effective channel information on the first 2D domain may be obtained based on the obtained channel estimate.

에 대한 수학식 21과 같은 연산에 기초하여 제1 2D 도메인 상의 유효 채널 정보

를 획득할 수 있다.Specifically, the demodulator may perform channel estimation using reference signals allocated to resources on the second 2D domain. The demodulator may calculate a channel equalization coefficient on the second 2D domain from the channel estimate on the domain of the channel estimation. The demodulator may perform channel equalization using the channel equalization coefficient calculated in the second 2D domain. The demodulator may calculate an effective channel to which channel equalization is applied. The demodulator may convert an effective channel on the second 2D domain into an effective channel on the first 2D domain. For example, the demodulator may include a first estimation information matrix

Effective channel information on the first 2D domain based on the operation of Equation 21 for

can be obtained.

Method 2) When the demodulator performs channel estimation using reference signals allocated to resources on the first 2D domain and converts the obtained channel estimate into channel information on the second 2D domain, the demodulator determines the corresponding channel estimate and the applied channel equalization coefficient on the second 2D domain may be used to obtain an effective channel on the first 2D domain.

를 획득할 수 있다.Specifically, the demodulator may perform channel estimation using reference signals allocated to resources on the first 2D domain. The demodulator may convert the channel estimate on the first 2D domain into the channel estimate on the second 2D domain. The demodulator may calculate a channel equalization coefficient on the second 2D domain based on the channel estimate on the second 2D domain. The demodulator may perform channel equalization using the channel equalization coefficient calculated in the second 2D domain. The demodulator may calculate an effective channel to which channel equalization is applied. The demodulator may convert the effective channel calculated on the second 2D domain into an effective channel on the first 2D domain. For example, the demodulator provides effective channel information on the first 2D domain based on the operation shown in Equation (22).

can be obtained.

Method 3) The demodulator despreads the signal obtained according to the channel equalization on the second 2D phase according to step S930 to the first 2D domain (ie, post-processing on the first 2D domain) and demapping on the first 2D domain, followed by the first Channel estimation may be performed again on the 2D domain.

Specifically, the demodulator may obtain the channel estimate on the second 2D domain in the same manner as in method 1) or method 2). The demodulator may calculate a channel equalization coefficient on the second 2D domain based on the channel estimate on the second 2D domain. The demodulator may perform channel equalization using the channel equalization coefficient calculated in the second 2D domain. The demodulator may convert a received signal to which channel equalization is applied on the second 2D domain into a signal on the first 2D domain. The demodulator may perform channel estimation using assigned reference signals from a received signal converted into a signal on the first 2D domain. The demodulator may obtain an effective channel estimate on the first 2D domain to which channel equalization on the first 2D domain is applied. The obtained effective channel estimate may be expressed as Equation (23).

는 수학식 24와 같이 정의될 수 있다.In Equation 20, corresponding to the denominator of each term

can be defined as in Equation 24.

는 행렬

의 k번째 대각 원소에 해당할 수 있고,

는 수학식 25와 같이 정의될 수 있다. In Equation 24,

is the matrix

may correspond to the kth diagonal element of

can be defined as in Equation 25.

는 수학식 26과 같이 정의될 수 있다.In Equation 25,

can be defined as in Equation 26.

의 정보들이 부호화 비트들의 원 순서로 수집될 수 있고, 수집된 정보들이 수신 노드에 포함되는 채널 복호기에 입력되어 채널 복호화가 수행될 수 있다. 이 때, 필요한 경우 디인터리빙, HARQ 콤바이닝(combining), 레이트-디매칭(rate-dematching) 등의 동작을 거친 후에 채널 복호화가 수행될 수 있다. 채널 복호화 후 채널 복호기는 정보 비트(또는 메시지 비트)들을 출력할 수 있고, 필요 시 CRC 확인에 성공할 경우 해당 정보 비트의 수신이 완료될 수 있다. 만약 송신 노드에서 데이터가 복수의 코드 블록들로 분할되어 전송되었을 경우, CRC 확인은 각각의 코드 블록 별로 수행될 수 있다. 수신 노드는 모든 코드 블록들에 대한 CRC 확인에 성공할 경우 모든 코드 블록들을 통합(desegmentation)한 후 전송 블록의 CRC 확인을 수행할 수 있다. 전송 블록의 CRC 확인에 성공할 경우, 최종적으로 정보 비트들의 수신이 완료될 수 있다.Calculated as in Equation 20

The information of may be collected in the original order of the encoding bits, and the collected information may be input to a channel decoder included in the receiving node to perform channel decoding. In this case, if necessary, channel decoding may be performed after performing operations such as deinterleaving, HARQ combining, and rate-dematching. After channel decoding, the channel decoder may output information bits (or message bits), and if necessary, if the CRC check succeeds, reception of the corresponding information bits may be completed. If the transmitting node divides data into a plurality of code blocks and transmits the data, the CRC check may be performed for each code block. If the receiving node succeeds in CRC checking for all code blocks, it may perform CRC check of the transport block after de-segmentation of all code blocks. When the CRC check of the transport block is successful, the reception of information bits may be finally completed.

[Linear Channel Equalization on First 2D Domain]

Hereinafter, a first embodiment of the channel equalization operation in the first 2D domain according to step S960 will be described. In an embodiment of the communication system, the demodulator may obtain post-processed and demapping data symbols on the first 2D domain through step S950. The demodulator may perform channel equalization on the data symbols obtained for each resource block in the first 2D domain (S960). Here, the channel equalization operation according to step S960 may correspond to a linear channel equalization operation or a multi-tap channel equalization operation.

로 표현할 수 있다. 복조부는 행렬

에 대한 채널 등화를 수행할 수 있다. 채널 등화를 거친 출력 행렬

의 벡터화 형태인

는, 수학식 27과 같이 표현될 수 있다.Specifically, the demodulator may acquire signals or data symbols that have been post-processed and demapping in the first 2D domain through steps S940 and S950. The signal obtained by the demodulator through step S950 is converted into a signal matrix

can be expressed as The demodulator is a matrix

Channel equalization may be performed for . Output matrix after channel equalization

is a vectorized form of

can be expressed as in Equation 27.

는 S960 단계에 따른 채널 등화 연산에 대응되는 제2 채널 등화 행렬일 수 있다. 제2 채널 등화 행렬

은 수학식 28 또는 수학식 29와 같이 정의될 수 있다.In Equation 27,

may be the second channel equalization matrix corresponding to the channel equalization operation according to step S960. second channel equalization matrix

may be defined as Equation 28 or Equation 29.

는

로 정의될 수 있다.Equation 28 can be viewed as representing the definition of the second channel equalization matrix according to the multi-tap zero forcing (ZF) equalization method. Equation 29 can be viewed as representing the definition of the second channel equalization matrix according to the multi-tap minimum mean squared error (MMSE) equalization method. in Equation 29

Is

can be defined as

Ideal channel estimation information used for channel equalization according to step S960 may be defined as in Equation (30).

를 획득할 수 있다. 복조부는 제1 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여 채널 추정을 수행함으로써 채널 추정 정보를 획득할 수 있다. 또는, 복조부는 또는, 복조부는 제2 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여 채널 추정을 수행할 수 있고, 수행된 채널 추정 결과를 제1 2D 도메인 상의 채널 추정 정보

로 변환할 수도 있다. 이를테면, 수학식 31과 동일 또는 유사할 수 있다.Meanwhile, in an actual communication system, a demodulator uses channel estimation information based on actual measurement information for a predetermined reference signal.

can be obtained. The demodulator may obtain channel estimation information by performing channel estimation based on one or more reference signals allocated to one or more resources in each resource block on the first 2D domain. Alternatively, the demodulator or the demodulator may perform channel estimation based on one or more reference signals allocated to one or more resources in each resource block on the second 2D domain, and convert the result of the performed channel estimation to a channel on the first 2D domain. estimated information

can also be converted to For example, it may be the same as or similar to Equation 31.

는 제2 2D 도메인 상의 각 자원 블록 내의 하나 이상의 자원에 할당된 하나 이상의 기준신호에 기초하여 획득된 채널 추정 정보에 해당할 수 있다. 즉, 수학식 31에 따르면, 제2 2D 도메인 상에서의 측정에 의해 획득된 자원 블록 별 채널 추정 정보

가 제1 2D 도메인 상에서의 자원 블록 별 채널 추정 정보

로 변환될 수 있다. 또는, 복조부는 제1 및 제2 2D 도메인 상의 자원들에 할당된 기준 신호들을 함께 이용하여 채널 추정 정보를 획득할 수도 있다.In Equation 31,

may correspond to channel estimation information obtained based on one or more reference signals allocated to one or more resources in each resource block on the second 2D domain. That is, according to Equation 31, channel estimation information for each resource block obtained by measurement in the second 2D domain

Channel estimation information for each resource block in the first 2D domain

can be converted to Alternatively, the demodulator may acquire channel estimation information by using reference signals allocated to resources on the first and second 2D domains together.

는 S970 단계에서 행렬

를 대체할 수 있다. 제1 2D 도메인 상에서의 채널 등화를 거친 출력 행렬

또는 출력 행렬

에 기초하여 획득되는 데이터 심볼들이 복조부에서의 복조 동작의 결과물로서 출력될 수 있다. 여기서, 각 데이터 심볼들의 부호화된 비트들에 대한 LLR(log-likelihood ratio)이, 수학식 32와 같이 계산될 수 있다.In operation S960, the demodulator may perform post-processing and a channel equalization operation on the demapping signal from resources on the first 2D domain based on the first embodiment of the channel equalization operation on the first 2D domain. In this case, the output matrix after channel equalization

is the matrix in step S970

can be substituted for Output matrix subjected to channel equalization in the first 2D domain

or output matrix

Data symbols obtained based on ? may be output as a result of a demodulation operation in the demodulator. Here, a log-likelihood ratio (LLR) for the coded bits of each data symbol may be calculated as in Equation 32.

에서,

일 수 있다.

은 제1 2D 도메인 상에서의 채널 등화를 거친 데이터 심볼

를 구성하는 j번째 비트에 대한 LLR을 의미할 수 있다. 수학식 32에서,

는 i번째 변조 알파벳에 매핑되는 j번째 비트를 의미할 수 있다. 수학식 32에서,

는 Q-ary 데이터 심볼 변조에 대한 변조 알파벳 집합을 의미할 수 있다.

는 벡터

의 k번째 원소일 수 있고,

는 행렬

를 벡터화 시킨 벡터(즉,

)에 해당할 수 있다.

는 행렬

의 대각 성분들을 의미할 수 있다. 행렬

는 제1 2D 도메인 상의 g번째 자원 블록 내 자원들에 대한 유효 채널 추정치 행렬을 의미할 수 있으며, 제1 2D 도메인 상의 채널 등화 연산(

)의 영향이 반영되었을 수 있다.of Equation 32

at,

can be

is a data symbol that has undergone channel equalization in the first 2D domain

It may mean an LLR for the j-th bit constituting . In Equation 32,

may mean the j-th bit mapped to the i-th modulation alphabet. In Equation 32,

may mean a modulation alphabet set for Q-ary data symbol modulation.

is vector

may be the kth element of

is the matrix

vectorized vector (i.e.,

) may be applicable.

is the matrix

may mean the diagonal components of . procession

may mean an effective channel estimate matrix for resources in the g -th resource block on the first 2D domain, and a channel equalization operation on the first 2D domain (

) may have been reflected.

는 수학식 33과 같이 정의될 수 있다.In Equation 32, corresponding to the denominator of each term

can be defined as in Equation 33.

는 행렬

의 k번째 대각 원소에 해당할 수 있고,

는 수학식 34와 같이 정의될 수 있다. In Equation 33,

is the matrix

may correspond to the kth diagonal element of

can be defined as in Equation 34.

의 정보들이 부호화 비트들의 원 순서로 수집될 수 있고, 수집된 정보들이 수신 노드에 포함되는 채널 복호기에 입력되어 채널 복호화가 수행될 수 있다. 이 때, 필요한 경우 디인터리빙, HARQ 콤바이닝(combining), 레이트-디매칭(rate-dematching) 등의 동작을 거친 후에 채널 복호화가 수행될 수 있다. 채널 복호화 후 채널 복호기는 정보 비트(또는 메시지 비트)들을 출력할 수 있고, 필요 시 CRC 확인에 성공할 경우 해당 정보 비트의 수신이 완료될 수 있다. 만약 송신 노드에서 데이터가 복수의 코드 블록들로 분할되어 전송되었을 경우, CRC 확인은 각각의 코드 블록 별로 수행될 수 있다. 수신 노드는 모든 코드 블록들에 대한 CRC 확인에 성공할 경우 모든 코드 블록들을 통합(desegmentation)한 후 전송 블록의 CRC 확인을 수행할 수 있다. 전송 블록의 CRC 확인에 성공할 경우, 최종적으로 정보 비트들의 수신이 완료될 수 있다.Calculated as in Equation 32

The information of may be collected in the original order of the encoding bits, and the collected information may be input to a channel decoder included in the receiving node to perform channel decoding. In this case, if necessary, channel decoding may be performed after performing operations such as deinterleaving, HARQ combining, and rate-dematching. After channel decoding, the channel decoder may output information bits (or message bits), and if necessary, if the CRC check succeeds, reception of the corresponding information bits may be completed. If the transmitting node divides data into a plurality of code blocks and transmits the data, the CRC check may be performed for each code block. If the receiving node succeeds in CRC checking for all code blocks, it may perform CRC check of the transport block after de-segmentation of all code blocks. When the CRC check of the transport block is successful, the reception of information bits may be finally completed.

[Turbo Channel Equalization on the 1st 2D Domain]

Hereinafter, a second embodiment of the channel equalization operation in the first 2D domain according to step S960 will be described. In an embodiment of the communication system, the demodulator may obtain post-processed and demapping data symbols on the first 2D domain through step S950. The demodulator may perform channel equalization on the data symbols obtained for each resource block in the first 2D domain (S960). Here, the channel equalization operation according to step S960 may be performed based on the turbo channel equalization method. In the turbo channel equalization operation in the first 2D domain, based on the LLR value of the coded bits output from the channel decoder, interference between data symbols generated from other resources in the first 2D domain is removed and linear channel equalization is performed. and the like may be performed. In addition, in the turbo channel equalization operation in the first 2D domain, transmission/reception reliability may be improved by reflecting a priori LLR when calculating the LLR of each bit of the original data symbol. Each LLR of the coded bits output from the channel equalizer performing turbo channel equalization may be input to a channel decoder or a deinterleaving unit, and based on this, each LLR (post LLR (a) of the coded bits output after channel decoding) Information of posterior LLR) and/or extrinsic LLR) may be obtained. The obtained LLR information may be input to a channel equalizer after interleaving, and the channel equalizer may perform channel equalization according to a turbo channel equalization method. The channel equalizer may repeatedly perform the above-described channel equalization operations until channel decoding succeeds within the maximum number of turbo iterations. As the number of turbo iterations increases, the reliability of the LLR of the encoding bits may be improved, and the reception success rate of the transport blocks may be improved.

는 수학식 35와 같이 표현될 수 있다.Specifically, the demodulator may acquire signals or data symbols that have been post-processed and demapping in the first 2D domain through steps S940 and S950. The channel equalizer may perform turbo channel equalization on the obtained data symbols. Channel-equalized data symbol for the k-th data symbol in the g-th resource block on the first 2D domain

can be expressed as in Equation 35.

는 벡터

의 k번째 요소에 해당할 수 있고, 벡터

는 터보 채널 등화된 출력 행렬

를 벡터화한 벡터(즉,

)에 해당할 수 있다. 벡터

는 행렬

를 구성하는 k번째 벡터일 수 있다. In Equation 35,

is vector

may correspond to the kth element of

is the turbo channel equalized output matrix

a vectorized vector of (i.e.,

) may be applicable. vector

is the matrix

It may be the k-th vector constituting .

일 수 있다.In Equation 35,

can be

일 수 있다.

can be

일 수 있다.

can be

일 수 있다.

can be

및

는 수학식 36 및 37과 같이 정의될 수 있다.here,

and

may be defined as in Equations 36 and 37.

의 각 비트들에 대한 사전 LLR(a priori LLR)이 주어지지 않는 경우(이를테면, 터보 반복에서 최초 등화 시),

는 0으로 설정될 수 있고,

는 1로 설정될 수 있다.In Equation 36 and Equation 37,

If a priori LLR for each bit of is not given (for example, at the time of initial equalization in turbo iteration),

can be set to 0,

may be set to 1.

는 수학식 38과 같이 정의될 수 있다.In Equation 36 and Equation 37,

can be defined as in Equation 38.

는 수학식 39와 같이 정의될 수 있다.In Equation 38,

can be defined as in Equation 39.

는 i번째 데이터 변조 알파벳인

로 매핑되는 j번째 비트를 의미할 수 있다.In Equation 39,

is the i-th data modulation alphabet

may mean the j -th bit mapped to .

은

로 매핑되는 j번째 비트에 대한 사전 LLR(a priori LLR)을 의미할 수 있다.

은 채널 복호기에서 출력되는 사후 LLR(a posterior LLR)들을 디인터리빙함으로써 구할 수 있다.in Equation 38

silver

It may mean a priori LLR (a priori LLR) for the j -th bit mapped to .

can be obtained by deinterleaving a posterior LLRs output from the channel decoder.

A log-likelihood ratio (LLR) for coded bits of data symbols subjected to channel equalization for each resource block in the first 2D domain may be calculated as in Equation 40.

에서,

일 수 있다.

은 제1 2D 도메인 상의 터보 채널 등화를 거친 데이터 심볼

을 구성하는 j번째 비트에 대한 LLR을 의미할 수 있다. 수학식 40에서,

는 수학식 41과 같이 정의될 수 있다.of Equation 40

at,

can be

is a data symbol that has undergone turbo channel equalization on the first 2D domain

It may mean an LLR for the j-th bit constituting . In Equation 40,

can be defined as in Equation 41.

는 수학식 42와 같이 정의될 수 있다.In Equation 40, corresponding to the denominator of each term

can be defined as in Equation 42.

은

로 매핑되는 l번째 비트에 대한 사전 LLR(a priori LLR)을 의미할 수 있다.

은 채널 복호기에서 출력되는 외적 LLR(extrinsic LLR)들을 디인터리빙함으로써 구할 수 있다. 각각의 외적 LLR 값들은, 대응되는 사후 LLR(a posterior LLR)에서 사전 LLR(a priori LLR)을 뺀 값으로 결정될 수 있다. 최초 터보 채널 등화 시에는,

은 0으로 설정될 수 있다. in Equation 40

silver

It may mean a priori LLR (a priori LLR) for the l-th bit mapped to .

can be obtained by deinterleaving extrinsic LLRs output from the channel decoder. Each of the extrinsic LLR values may be determined as a value obtained by subtracting a priori LLR (a priori LLR) from a corresponding posterior LLR (a posterior LLR). At the time of first turbo channel equalization,

may be set to 0.

의 정보들이 부호화 비트들의 원 순서로 수집될 수 있고, 수집된 정보들이 수신 노드에 포함되는 채널 복호기에 입력되어 채널 복호화가 수행될 수 있다. 이 때, 필요한 경우 디인터리빙, HARQ 콤바이닝(combining), 레이트-디매칭(rate-dematching) 등의 동작을 거친 후에 채널 복호화가 수행될 수 있다. 채널 복호화 후 채널 복호기는 정보 비트(또는 메시지 비트)들을 출력할 수 있고, 필요 시 CRC 확인에 성공할 경우 해당 정보 비트의 수신이 완료될 수 있다. 만약 송신 노드에서 데이터가 복수의 코드 블록들로 분할되어 전송되었을 경우, CRC 확인은 각각의 코드 블록 별로 수행될 수 있다. 수신 노드는 모든 코드 블록들에 대한 CRC 확인에 성공할 경우 모든 코드 블록들을 통합(desegmentation)한 후 전송 블록의 CRC 확인을 수행할 수 있다. 전송 블록의 CRC 확인에 성공할 경우, 최종적으로 정보 비트들의 수신이 완료될 수 있다.Calculated as in Equation 40

The information of may be collected in the original order of the encoding bits, and the collected information may be input to a channel decoder included in the receiving node to perform channel decoding. In this case, if necessary, channel decoding may be performed after performing operations such as deinterleaving, HARQ combining, and rate-dematching. After channel decoding, the channel decoder may output information bits (or message bits), and if necessary, if the CRC check succeeds, reception of the corresponding information bits may be completed. If the transmitting node divides data into a plurality of code blocks and transmits the data, the CRC check may be performed for each code block. If the receiving node succeeds in CRC checking for all code blocks, it may perform CRC check of the transport block after de-segmentation of all code blocks. When the CRC check of the transport block is successful, the reception of information bits may be finally completed.

On the other hand, if the CRC check is not successful, the receiving node interleaves a posterior LLR (a posterior LLR) and/or an extrinsic LLR (extrinsic LLR) of the coded bits output from the channel decoder, and then the channel on the first 2D domain Can be used when lighting. Specifically, the receiving node may perform interference cancellation during channel equalization in the first 2D domain by using an interleaved a posterior LLR and/or an extrinsic LLR. Alternatively, LLR calculation of each coded bit is performed by reflecting as a priori LLR (a priori LLR) upon demapping of data symbols in the first 2D domain.

As described above, the receiving node may deinterleave the LLR values output from the channel equalizer and input the LLR values to the channel decoder. Based on this, the receiving node may perform CRC check after performing channel decoding again. If the CRC check is successful, the reception of information bits may be finally completed. If the CRC check is not successful, the receiving node may repeatedly perform the above-described turbo channel equalization operations until channel decoding succeeds within the maximum number of turbo iterations. As the number of turbo iterations increases, the reliability of the LLR of the encoding bits may be improved, and the reception success rate of the transport blocks may be improved.

[Reporting method for turbo channel equalization]

Each terminal included in the communication system may use a different channel equalization scheme according to its capabilities. In the case of a terminal supporting turbo channel equalization, the maximum reception delay may be limited by the maximum number of turbo repetitions. Also, even when the maximum turbo iteration number limit is the same, the reception processing delay may be different depending on the hardware performance of the terminal. The base station may set the HARQ feedback timing in consideration of the reception processing capability of the terminal.

The terminal may transmit a terminal capability report to the base station, wherein the terminal capability report may include at least information related to a channel equalization scheme that the terminal can support. For example, the terminal may support a linear channel equalization method or a non-linear channel equalization method. As an example of the nonlinear channel equalization method, the terminal may support the turbo channel equalization method. The terminal may transmit to the base station a terminal capability report including information on a channel equalization method supported by the terminal among the channel equalization methods.

In an embodiment of the communication system, the terminal capability report may include information on whether the turbo channel equalization method is supported. Or, the UE capability report is the size of the transport block (or the size of the predefined representative transport block), the MCS (or the predefined representative MCS or CQI or the predefined representative CQI) and/or the size of the 2D resource block Information on reception processing delay according to each turbo channel equalization number may be included.

The terminal may transmit a terminal capability report to the base station, and the terminal capability report may include at least information on whether or not to support turbo channel equalization. Alternatively, the UE capability report may include the size of the transport block (or the size of a predefined representative transport block, etc.), MCS (or predefined representative MCS, CQI, predefined representative CQI, etc.) and/or 2D resource block It may include information on the reception processing delay according to the number of turbo channel equalizations for each size of . The base station may semi-statically and/or dynamically configure the HARQ feedback timing or HARQ feedback resource (hereinafter, collectively referred to as HARQ feedback timing) to the terminal based on the information of the terminal capability report received from each terminal.

When the terminal does not receive a separate HARQ feedback timing from the base station, HARQ feedback may be performed based on a predefined HARQ feedback timing. On the other hand, when the terminal receives the HARQ feedback timing set semi-statically from the base station, the terminal may change the HARQ feedback timing based on the configured HARQ feedback timing information, and may perform HARQ feedback based on the changed HARQ feedback timing, The changed HARQ feedback timing can be maintained until the next setting. On the other hand, when the terminal receives the HARQ feedback timing dynamically set from the base station, the terminal receives the transport block related to the dynamically set HARQ feedback timing information (or assignment information including the set HARQ feedback timing information, etc.) However, HARQ feedback may be performed based on the set HARQ feedback timing. In dynamically setting the HARQ feedback timing to the terminal, the base station may semi-statically set candidate values of the HARQ feedback timing in advance. If the base station dynamically configures the HARQ feedback timing for the terminal after semi-statically setting it, the terminal temporarily replaces the previously set HARQ feedback timing information with the dynamically configured HARQ feedback timing information. can

When the terminal receives the HARQ feedback timing semi-statically configured from the base station, and additionally receives the HARQ feedback timing (which may be limited to be ahead of the semi-statically configured HARQ feedback timing) dynamically, the terminal receives the HARQ feedback timing set dynamically The HARQ feedback timing set semi-statically is set only when the corresponding feedback is feedback on reception failure or regardless of whether the reception of the processed turbo channel equalization is successful or not at the corresponding timing until the HARQ feedback information transmission is ready. Whether or not reception of the processed turbo channel equalization has been successful may be fed back at a corresponding timing until HARQ feedback information transmission is prepared.

The base station may set different CSI measurement/reporting settings for each terminal based on the information of the terminal capability report received from each terminal. As described above, in the turbo channel equalization method, the reception success rate and the reception processing delay may be different depending on the maximum number of turbo iterations. Meanwhile, in transport block transmission, the required transmission success rate and transmission delay may be different depending on the required transmission quality (for each service). In order for the base station to perform link adaptation to enable efficient transmission according to the transmission quality required for the terminal, the terminal receives the requested reception success rate and/or the requested reception processing delay (or the requested HARQ feedback timing, etc.) for each CSI (channel state information) or CQI (channel quality information) can be measured and reported. The base station may semi-statically set the request reception success rate and/or the request reception processing delay (or the requested HARQ feedback timing, etc.) to the terminal as CSI measurement/report configuration information. Each terminal is capable of processing within the reception processing delay from the measured channel according to the capability of the terminal (or until the HARQ feedback information transmission at the requested HARQ feedback timing is ready), and / or CQI that can achieve the requested reception success rate may be determined, and the determined CQI may be reported to the base station. The base station may not set CQI measurement for each requested transmission quality in the case of a terminal that does not support turbo channel equalization. Alternatively, the base station may determine and report CQIs only for each requested reception success rate in the case of a terminal not supporting turbo channel equalization.

[Hybrid linear channel equalization on second 2D domain and first 2D domain]

에 대해 multi-tap 선형 채널 등화를 거친 출력 행렬

는,

와 같이 표현될 수 있다. 여기서,

는

일 수 있고(다중-탭 ZF 채널 등화의 경우), 또는

(다중-탭 MMSE 채널 등화의 경우)일 수 있다.The demodulator may perform channel equalization for each resource group in the first 2D domain on data symbols that have been demodulated and demapping in the second 2D domain and post-processed and demapping in the first 2D domain. Multicarrier demodulated and demapped signal matrix for the g -th resource group on the first 2D domain

output matrix subjected to multi-tap linear channel equalization with respect to

Is,

can be expressed as here,

Is

can be (for multi-tap ZF channel equalization), or

(for multi-tap MMSE channel equalization).

등과 같이 주어질 수 있지만, 실제적으로는 기준 신호로부터 직접 추정한 실제 채널 추정치

가 사용될 수 있다. 이를테면, 제1 2D 도메인 상의 해당 자원 블록 내 자원(들)에 할당된 기준 신호(들)로부터 추정된 채널 추정치가 사용될 수 있다. 또는, 제2 2D 도메인 상의 해당 자원 블록 내 자원(들)에 할당된 기준 신호(들)로부터 추정된 채널을 제1 2D 도메인 상의 채널로 변환된 채널 추정치가 사용될 수 있다. 이 경우,

일 수 있다. 여기서,

일 수 있고,

일 수 있다.

는 제2 2D 도메인 상의 g번째 자원 블록 내 자원(들)에 할당된 기준 신호(들)로부터 추정한 채널 추정치를 의미하고,

는

를 제1 2D 도메인 상의 채널로 변환한 채널 추정치를 의미할 수 있다. 또는, 제2 2D 도메인 상과 제1 2D 도메인 상 각각의 해당 자원 블록 내 자원(들)에 할당된 기준 신호(들)을 함께 이용하여 추정한 채널 추정치가 사용될 수도 있다. 한편,

일 수 있다.Here, the ideal channel estimate used for channel equalization is

etc., but in practice it is the actual channel estimate directly estimated from the reference signal.

can be used. For example, a channel estimate estimated from reference signal(s) allocated to resource(s) in a corresponding resource block on the first 2D domain may be used. Alternatively, a channel estimate obtained by converting a channel estimated from the reference signal(s) allocated to the resource(s) in the corresponding resource block on the second 2D domain into a channel on the first 2D domain may be used. in this case,

can be here,

can be,

can be

Means a channel estimate estimated from the reference signal (s) allocated to the resource (s) in the g -th resource block on the second 2D domain,

Is

may mean a channel estimate converted into a channel on the first 2D domain. Alternatively, a channel estimate estimated by using the reference signal(s) allocated to the resource(s) in each corresponding resource block on the second 2D domain and the first 2D domain together may be used. Meanwhile,

can be

After performing post-processing and demapping of the demodulated signal subjected to channel equalization for each resource group in the second 2D domain from the resources in each corresponding resource group in the first 2D domain as described above, the coded bits of each data symbol are LLR can be calculated as in Equation 43.

은 제1 2D 상의 선형 채널 등화 및 제2 2D 상의 선형 채널 등화 후 데이터 심볼

의 j번째 bit에 대한 LLR을 의미할 수 있다.

일 수 있고,

일 수 있고,

일 수 있다.

일 수 있으며, 이는 제1 2D 도메인 상의 g번째 자원 그룹 내 자원들에 대한 유효 채널 추정치 행렬(제1 2D 도메인 상의 채널 등화 영향을 반영함)을 의할 수 있다.

일 수 있고,

일 수 있다. In Equation 43,

is the data symbol after linear channel equalization on the first 2D and linear channel equalization on the second 2D

may mean the LLR for the j-th bit of

can be,

can be,

can be

, which may be based on an effective channel estimate matrix (reflecting the channel equalization effect on the first 2D domain) for resources in the g-th resource group on the first 2D domain.

can be,

can be

의 정보들이 부호화 비트들의 원 순서로 수집될 수 있고, 수집된 정보들이 수신 노드에 포함되는 채널 복호기에 입력되어 채널 복호화가 수행될 수 있다. 이 때, 필요한 경우 디인터리빙, HARQ 콤바이닝(combining), 레이트-디매칭(rate-dematching) 등의 동작을 거친 후에 채널 복호화가 수행될 수 있다. 채널 복호화 후 채널 복호기는 정보 비트(또는 메시지 비트)들을 출력할 수 있고, 필요 시 CRC 확인에 성공할 경우 해당 정보 비트의 수신이 완료될 수 있다. 만약 송신 노드에서 데이터가 복수의 코드 블록들로 분할되어 전송되었을 경우, CRC 확인은 각각의 코드 블록 별로 수행될 수 있다. 수신 노드는 모든 코드 블록들에 대한 CRC 확인에 성공할 경우 모든 코드 블록들을 통합(desegmentation)한 후 전송 블록의 CRC 확인을 수행할 수 있다. 전송 블록의 CRC 확인에 성공할 경우, 최종적으로 정보 비트들의 수신이 완료될 수 있다.Calculated as in Equation 43

The information of may be collected in the original order of the encoding bits, and the collected information may be input to a channel decoder included in the receiving node to perform channel decoding. In this case, if necessary, channel decoding may be performed after performing operations such as deinterleaving, HARQ combining, and rate-dematching. After channel decoding, the channel decoder may output information bits (or message bits), and if necessary, if the CRC check succeeds, reception of the corresponding information bits may be completed. If the transmitting node divides data into a plurality of code blocks and transmits the data, the CRC check may be performed for each code block. If the receiving node succeeds in CRC checking for all code blocks, it may perform CRC check of the transport block after de-segmentation of all code blocks. When the CRC check of the transport block is successful, the reception of information bits may be finally completed.

Steps S910 to S970 constituting the demodulation process performed by the demodulator described above with reference to FIG. 9 or the functional blocks corresponding to each step are the same as those of matrix operations or vector operations such as Equations 6 to 42. expressed as a form. However, this is only an example for convenience of description, and the embodiment of the present invention is not limited thereto. Expression expressions based on matrix operations are for simply mathematically expressing the effect of a function between input and output of each functional block. As an example, a product with a DFT matrix may be processed with an FFT and a product with an IDFT matrix may be processed with an IFFT. The multiplication with the receive pulse shaping matrix GR may be performed by multiplying the temporal samples of the modulated signal with respective corresponding coefficients of the pulse. If the receive pulse shaping matrix includes CP removal or downsampling, this can be done by taking only some time samples or accumulating periodically repeating time samples. Resource mapping may be processed as indexing (or mapping) rather than actual matrix operation.

[2D Spread Resource Block Size Setting Method]

The base station may set the size of the 2D spreading resource block to the terminal. The UE may perform spreading from the first 2D domain to the second 2D domain for each 2D spreading resource block during transmission using the size of the 2D spreading resource block set by the base station. Alternatively, the UE may perform despreading from the second 2D domain to the first 2D domain for each 2D spreading resource block at the time of reception by using the size of the 2D spreading resource block set by the base station. Here, the size of the 2D spreading resource block may be set in the following manner.

The base station may set the size of the 2D resource spreading block to be the same or different for each link type such as downlink, uplink, and sidelink. The base station may set the size of the 2D spreading resource block differently for each terminal or for each terminal group. In other words, the base station may set the size of the 2D spreading resource block to be UE-specific or UE-group-specific. Alternatively, the UE may set the size of the 2D spreading resource block to be common to at least some of a plurality of UEs or a plurality of UE groups.

Meanwhile, during wireless transmission, the size of a resource allocated for a terminal or a specific transmission may vary. Here, the base station may determine the size of the 2D spreading resource block differently or uniformly according to the allocated resource size. Specifically, resource allocation information on the second 2D domain may be included in allocation information for downlink, uplink, sidelink, or other link type allocated by the base station to the terminal. The allocated resources on the second 2D domain may be divided by the size of the 2D spreading resource block configured in the base station. If the resources on the second 2D domain are not accurately divided by the size of the configured 2D spreading resource block, some of the spreading resource blocks may be defined to have a size smaller than the size of the 2D spreading resource block configured by the base station, and the remaining 2D spreading resource blocks may be defined to have a smaller size. The resource blocks may be defined to have a size of a 2D spreading resource block configured in the base station. Here, the resource block defined to have a size smaller than the size of the 2D spreading resource block configured in the base station may be composed of time and/or frequency resources having a relatively high index. Alternatively, a resource block defined to have a size smaller than the size of the 2D spreading resource block configured in the base station may be configured with time and/or frequency resources having a relatively low index.

The size of the 2D spreading resource block may be expressed as a combination of a Doppler-to-time spreading resource size for spreading from the Doppler domain to the time domain and a delay-to-frequency spreading resource size. For example, the size of the 2D spreading resource block may be set in the following manner.

Sets the size of the Doppler-to-time block spreading from the Doppler domain to the time domain for each multi-carrier symbol (or OFDM symbol) in the TTI.

- For example, if the number of multicarrier symbols in TTI is given as 2, 7, 14, 28, 56, set the Doppler-to-time block size (unit: the number of multicarrier symbols or the number of OFDM symbols) for each

Set the delay-to-frequency block size for spreading from the delay domain to the frequency domain for each frequency resource block (RB) or subband or PRG (precoding resource group) size within the bandwidth

- For example, if the number of RBs in the bandwidth is given as 4, 8, 16, 32, 64, set the delay-to-frequency block size (unit: the number of subcarriers or the number of RBs or the number of subbands or the number of PRGs) for each

Resources indicated by resource allocation information on the second 2D domain may be limited to continuous allocation. Alternatively, the allocation may be continuous only within a spreading resource group consisting of a certain number of consecutive resources, and continuity may not be limited between the spreading resource groups. Alternatively, the continuity of all allocated resources may not be limited in allocation. If non-consecutive resource allocation in resource units or spread resource group units is allowed, logically continuous resources are sequentially configured after demapping from the second 2D domain, and logically continuous resources are set by the base station. It can be divided by the 2D spreading resource block size to correspond to the 2D spreading resource group. Alternatively, if non-consecutive resource allocation in units of a spreading resource group is allowed, the setting may be limited so that the 2D spreading resource block size is a multiple of the spreading resource group size (the two sizes may be limited to one time the same). have. Alternatively, the resource allocation itself may be limited so that the allocated resources on the second 2D domain corresponding to each 2D spread resource block have continuity regardless of the continuity of the allocated resources. That is, even if the resource allocation information supports non-contiguous resource allocation, resource allocation on the second 2D domain may be limited so that resources on the second 2D domain are allocated consecutively in units of at least the 2D spread resource block size. (Or the UE may not expect resource allocation that is not otherwise.)

The base station may signal the size of the 2D spreading resource block to each terminal, and each terminal may set the size of the 2D spreading resource block according to the signaling from the base station. Signaling on the size of the 2D spreading resource block may be performed in the following manner.

The size of the 2D spreading resource block may be set differently for each terminal or terminal group. Alternatively, the size of the 2D spreading resource block may be set to be the same for a plurality of terminals or a plurality of terminal groups.

The size of the spreading resource block may be set to be the same or different for each link type such as uplink, downlink, and sidelink.

- In the case of downlink, the base station transmits a signal through a multi-carrier modulation process based on the size of the 2D spreading resource block signaled to the terminal

- In the case of downlink, the terminal receives a signal through a multi-carrier demodulation process based on the size of the 2D spreading resource block set through signaling from the base station

- In the case of uplink, the terminal transmits a signal through a multi-carrier modulation process based on the size of the 2D spreading resource block set through signaling to the base station

- In the case of uplink, the base station receives a signal through a multi-carrier demodulation process based on the size of the 2D spreading resource block signaled to the terminal

Radio Resource Control (RRC) message signaling or MAC (Medium Access Control) CE (Control Element) signaling

- The UE changes the size setting of the 2D spreading resource block to the currently signaled setting. Retains the changed settings until the next signaling is received and changed

Combination of RRC message signaling and MAC CE signaling

- The base station sets the size candidate of the spreading resource block through RRC message signaling (the terminal changes the size setting of the 2D spreading resource block to the currently signaled setting. The changed setting is maintained until the next signaling is received and changed)

- The base station sets the size of the 2D spreading resource block by referring to a specific value from the candidate group set in advance through MAC CE signaling and RRC message signaling (the terminal changes to the currently signaled setting and receives the next signaling until it is changed) keep settings)

Combination of RRC message signaling and DCI (or UCI) signaling

- The base station sets the size candidate of the spreading resource block through RRC message signaling (the terminal changes the size setting of the 2D spreading resource block to the currently signaled setting. The changed setting is maintained until the next signaling is received and changed)

The base station sets the size of the 2D spreading resource block by referring to a specific value from the candidate group set in advance through DCI (or UCI) signaling or through RRC message signaling (the terminal receives the transport block associated with the signaled DCI (or UCI)) transmission), set the size of the 2D spreading resource block referred to by the base station

As a fallback mode, the base station may pre-define the total resource spread in which the number of spreading resource blocks is 1. Alternatively, the size of a specific resource block may be predefined

Signaling on whether 2D spreading is applied may be performed in the following manner.

The base station signals to the terminal whether 2D spreading is applied

- It may be a terminal (or terminal group) specific setting or a setting common to all terminals

- Can be set for each link type (uplink, downlink, sidelink, etc.) or can be a common setting regardless of link type

- One dimension of 2D can correspond to the frequency domain and the other dimension can correspond to the time domain.

- Whether or not spreading is applied for each dimension may be classified and signaled.

- A mode that does not apply spreading for both dimensions may correspond to, for example, OFDM (or OFDMA)

- A mode that applies spreading only in the frequency domain may correspond to, for example, SC-FDM (or SC-FDMA)

May be signaled via RRC message or MAC CE or DCI (or UCI)

- RRC message or MAC CE signaling: The terminal changes to the currently signaled setting and maintains the corresponding setting until the next signaling is received and changed

- DCI (or UCI) signaling: the UE applies whether 2D spreading is applied by limiting the reception (or transmission) of transport blocks related to the signaled DCI (or UCI)

- As a fallback mode, the base station can pre-define activation or deactivation of 2D spreading application.

[Downlink allocation method in case of multiple access only on the second 2D domain]

A downlink allocation method in the case of multiple access only on the second two-dimensional domain will be described. Here, the multiple access on the second 2D domain means orthogonally allocating and transmitting resources on the 2nd 2D domain to different terminals (or groups of terminals; hereinafter referred to as terminals). The base station transmits data symbols and reference signals mapped to resources on the first two-dimensional domain to the resources specifically allocated to the terminal on the second two-dimensional domain, as described above, in downlink transmission to each terminal. Multi-carrier modulation is performed by spreading.

The downlink allocation information includes at least a carrier indicator and/or bandwidth part indicator and/or resource allocation information on the second two-dimensional domain as time domain resource allocation information and frequency domain resource allocation information and/or modulation and coding scheme (MCS) and/or Or it may include a new data indicator (NDI) and / or redundancy version (RV) and / or HARQ process number. It does not exclude the inclusion of additional information not mentioned otherwise.

The frequency domain resource allocation information may be referred to as a resource block (RB) unit composed of a predetermined number (eg, 12) of subcarriers. The frequency domain resource allocation information may be configured as a bitmap indicating whether or not each RB is allocated or may be configured with an index indicating a start RB and the number of allocated RBs. The range of the RB may be limited to RBs within the bandwidth part (BWP) corresponding to the bandwidth part indicator.

The time domain resource allocation information may consist of an index indicating a start MC symbol (or OFDM symbol; hereinafter referred to as an MC symbol) and an MC symbol length. The frequency domain resources allocated above and the time domain resource allocation information are It supports only the allocation of contiguous MC symbols, but does not exclude non-consecutive time domain resource allocation and information about it.

The UE performs multicarrier demodulation on the MC symbols indicated by the time domain resource allocation information. After multicarrier demodulation, in each of the MC symbols on the time-frequency domain resource, data symbols (spreaded) are demapping from the subcarrier resources indicated by the frequency domain resource allocation information. If necessary, channel estimation and/or channel equalization on the second two-dimensional domain may be performed on the data symbols demapped on the second two-dimensional domain. As described above, the demapping data symbols correspond to each 2D spreading resource group according to a predefined rule. The above-described post-processing is performed for each spreading resource group and demapping is performed on the first 2D domain. For each spreading resource group, first two-dimensional channel estimation and/or channel equalization may be performed on the data symbols demapped on the first two-dimensional domain. For each data symbol after demodulation and channel equalization, data symbol demapping is performed according to MCS included in downlink allocation information to obtain LLR for each coded bit, and then information or message bits are generated through a channel decoding process. can be obtained

[Downlink allocation method in case of multiple access on first and second 2D domains]

A downlink allocation method in the case of multiple access in the second 2D domain and the first 2D domain will be described. The case of multiple access only on the first 2D domain without multiple access on the second 2D domain is regarded as a special case of multiple access on the second 2D domain and the first 2D domain. . Here, multiple access on the second two-dimensional domain is performed by orthogonally allocating resources on the first two-dimensional domain to different terminals (or groups of terminals; hereinafter referred to as terminals) (explicitly referred to as signaling to allocate or allocate resources). itself may be defined in advance or defined to be referred to implicitly from other allocation information), and multiple access in the first two-dimensional domain is to different terminals (or groups of terminals; hereinafter collectively referred to as terminals). This means that resources on the first two-dimensional domain are orthogonally allocated and transmitted. Multiple access on the first two-dimensional domain is not required between terminals that have multi-access on the second two-dimensional domain. Terminals allocated to the same resource in the second 2D domain may have multiple access in the first 2D domain. In the downlink transmission to each terminal, as described above, the base station maps data symbols and reference signals to the resources allocated specifically to the terminal on the first two-dimensional domain, and then specifies the terminal on the second two-dimensional domain. Multi-carrier modulation is performed by spreading to the allocated resources. In general, since data symbols mapped to resources on different first two-dimensional domains in the same spreading resource group experience the same channel, it may be desirable to allocate consecutive resources on the first two-dimensional domain to each terminal. . A UE-specific or UE-common reference signal(s) may be transmitted on the first two-dimensional domain. When the number of spreading resource groups is plural, resource allocation in the same first 2D domain may be limited to each spreading resource group, and resources allocated in the first 2D domain may be allocated to the spreading resource group according to a resource hopping rule. It may be applied differently. In addition to the above methods, other methods are not excluded. If both methods are supported (or all of a plurality of methods are supported), the base station may set in advance which rule to apply to the terminal.

Downlink allocation information includes at least a carrier indicator and/or bandwidth part indicator and/or Doppler domain resource allocation information and delay domain resource allocation information as resource allocation information on the first two-dimensional domain and/or modulation and coding scheme (MCS) and/or Or it may include a new data indicator (NDI) and / or redundancy version (RV) and / or HARQ process number. It does not exclude the inclusion of additional information not mentioned otherwise. The allocated resource itself on the second 2D domain may be defined in advance. Alternatively, resource allocation on the 2D domain may be defined in advance to be implicitly referred to from other allocation information. As an example, resource allocation on the second two-dimensional domain may be defined in advance as resources within the bandwidth part indicated by the bandwidth part indicator. As resource allocation information on the second 2D domain, time domain resource allocation information and/or Doppler domain resource allocation information may be included in downlink allocation information or may be configured by signaling through an RRC message or MAC CE. As resource allocation information on the second 2D domain, only time domain resource allocation information is set by signaling through downlink allocation information or RRC message or MAC CE, and frequency domain resource allocation information may be defined in advance. As resource allocation information on the second 2D domain, only frequency domain resource allocation information is set by signaling through downlink allocation information or RRC message or MAC CE, and time domain resource allocation information may be defined in advance. In time domain resource allocation signaling through downlink allocation information, the method described above in 'downlink allocation method in case of multiple access only in the second 2D domain' may be equally applied. In the frequency domain resource allocation signaling through downlink allocation information, the method described above in the 'downlink allocation method in case of multiple access only in the second 2D domain' may be equally applied.

The UE performs multicarrier demodulation on MC symbols indicated (or predefined) by the time domain resource allocation information (downlink allocation information or signaled in an RRC message or MAC CE). After multicarrier demodulation, in each of the MC symbols on the time-frequency domain resource, the frequency domain resource allocation information (downlink allocation information or signaled in an RRC message or MAC CE) indicates (or predefined) from subcarrier resources. Demaps (spreading) data symbols. If necessary, channel estimation and/or channel equalization on the second two-dimensional domain may be performed on the data symbols demapped on the second two-dimensional domain. As described above, the demapping data symbols correspond to each spreading resource group according to a predefined rule. The above-described post-processing is performed for each 2D spreading resource group, and demapping is performed from the resources indicated by the resource allocation information on the first 2D domain in a UE-specific manner for each spreading resource group. Channel estimation and/or channel equalization in the first two dimensions may be performed on the data symbols demapped on the first two-dimensional domain. If necessary, in order to mitigate/suppress/remove interference by multiple accesses on the first two dimensions within the same spreading resource group, jointly channel estimation across multiple-accessed terminals on the first two dimensions within the same spreading resource group and/or Alternatively, channel equalization may be performed. Data symbol demapping is performed on each data symbol that has been demodulated and channel equalized in this way to obtain an LLR for each coded bit, and then information or message bits can be obtained through a channel decoding process. A protection resource may be inserted between allocated resources of different terminals in order to limit the influence of interference between multi-accessed terminals on the first two-dimensionality within the same spreading resource group.

[Uplink allocation method]

In the above-described downlink allocation method, the 'downlink allocation method for multi-access only on the second 2D domain' and/or the above-described 'downlink allocation method for multi-access on the first and second 2D domains' can be applied in the same way. However, there is a difference in that the terminal performs transmission instead of reception according to the uplink allocation of the base station and the base station performs reception instead of transmission according to the uplink allocation. Also, the uplink allocation information may have a different configuration from the downlink allocation information, but at least the components listed as the downlink allocation information above may be included as the uplink allocation information.

According to an embodiment of the present invention, information bits in a transport block may be transmitted and received based on a modulation and demodulation operation of a multicarrier waveform based on the spreading of multiple 2D resource blocks. Accordingly, the diversity gain of the channel experienced by each symbol in the codeword can be improved. In addition, interference between data symbols according to multiplexing may be reduced or limited due to channel spreading.

According to an embodiment of the present invention, multi-carrier demodulation and channel equalization may be performed for each 2D resource block in the receiving node. Accordingly, the reception processing delay can be reduced. Here, the channel equalization may be performed based on a linear channel equalization method or a turbo channel equalization method. Accordingly, error rates such as BER, SER, and BLER may be reduced, and reception performance of the receiving node may be improved.

However, the effects that can be achieved by the modulation and demodulation method and apparatus in the wireless communication system according to the embodiments of the present invention are not limited to those mentioned above, and other effects not mentioned are described in the specification of the present application. From the configurations described in the present invention will be clearly understood by those of ordinary skill in the art.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer readable medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software.

Examples of computer-readable media include hardware devices specially configured to store and carry out program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as at least one software module to perform the operations of the present invention, and vice versa.

Although described with reference to the above embodiments, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. will be able

Claims (21)

A method of operating a first communication node in a communication system, the method comprising:
The data symbols constituting the first codeword to be transmitted to the second communication node of the communication system are divided into N symbol groups each including a plurality of symbols, so that a plurality of resources are distributed in the first two-dimensional (2D) domain, respectively. sequentially mapping N first spreading resource blocks configured to include and independently separated from each other;
The data symbols mapped for each of the N first spreading resource blocks are preprocessed in order to spread them for each of the N second spreading resource blocks configured to include a plurality of resources in a second 2D domain, respectively. step;
mapping the preprocessed data symbols to each of the N second spreading resource blocks; and
and multi-carrier-modulating the preprocessed and mapped data symbols for each of the N second spreading resource blocks for each of the plurality of resources included in the N second spreading resource blocks,
Wherein N is a natural number, the operating method of the first communication node. delete The method according to claim 1,
A first communication node, wherein a first dimension of the first 2D domain is a delay domain, a second dimension of the first 2D domain is a Doppler domain, and the N first spreading resource blocks are configured by delay-Doppler resource blocks. how it works. delete The method according to claim 1,
A first dimension of the second 2D domain is a frequency domain, a second dimension of the second 2D domain is a time domain, and the N second spreading resource blocks are composed of frequency-time resource blocks. How nodes work. The method according to claim 1,
The method of operation of the first communication node,
Prior to the sequential mapping for each of the N first spreading resource blocks,
performing, with the second communication node, a signaling procedure for information on sizes of the N first spreading resource blocks on the first 2D domain and the N second spreading resource blocks on the second 2D domain Further comprising, the method of operation of the first communication node. 7. The method of claim 6,
The step of performing the signaling procedure,
Receiving, from the second communication node providing a communication service to the first communication node, signaling on information on sizes of the N first spreading resource blocks and the N second spreading resource blocks , a method of operation of the first communication node. 7. The method of claim 6,
The step of performing the signaling procedure,
Signaling information on sizes of the N first spreading resource blocks and the N second spreading resource blocks to one or more communication nodes including the second communication node from which the first communication node provides a communication service A method of operating a first communication node, comprising the steps of. 7. The method of claim 6,
The step of performing the signaling procedure,
performing, with the second communication node, a signaling procedure on information of candidates having sizes of the N first spreading resource blocks and the N second spreading resource blocks; and
performing, with the second communication node, a signaling procedure on information indicating any one of the candidates of the size of the N first spreading resource blocks and the N second spreading resource blocks , a method of operation of the first communication node. A method of operating a first communication node in a communication system, the method comprising:
The radio signals received from the second communication node of the communication system are received for each of the plurality of resources included in N first spreading resource blocks configured to include a plurality of resources, respectively, in a first two-dimensional (2D) domain. multi-carrier demodulation;
identifying data symbols mapped to each of the N first spreading resource blocks based on a result of the multi-carrier demodulation;
demapping the data symbols mapped to each of the N first spreading resource blocks from the N first spreading resource blocks;
Despreading the data symbols demapped from the N first spreading resource blocks into N second spreading resource blocks configured to include a plurality of resources in a second 2D domain and separated independently from each other ) to post-processing (postprocessing) to;
The data symbols included in N symbol groups each including a plurality of symbols, which are post-processed and mapped to each of the N second spreading resource blocks, are sequentially retrieved from the N second spreading resource blocks. demapping; and
obtaining a first codeword based on the data symbols sequentially demapped from the N second spreading resource blocks;
Wherein N is a natural number, the operating method of the first communication node. 11. The method of claim 10,
The step of demapping from the N first spreading resource blocks includes:
checking information on the N first spreading resource blocks constituting the first 2D domain; and
demapping the data symbols mapped for each of the N first spreading resource blocks from the N first spreading resource blocks;
a first dimension of the first 2D domain is a frequency domain, a second dimension of the first 2D domain is a time domain, and the N first spreading resource blocks are composed of frequency-time resource blocks. how it works. 11. The method of claim 10,
The step of sequentially demapping from resources on the second 2D domain includes:
checking information on the N second spreading resource blocks constituting the second 2D domain; and
Based on the identified information on the N second spreading resource blocks, the data symbols divided into the N symbol groups, which are post-processed and mapped for each of the N second spreading resource blocks, are sequentially demapping from N second spreading resource blocks,
A first communication node, wherein a first dimension of the second 2D domain is a delay domain, a second dimension of the second 2D domain is a Doppler domain, and the N second spreading resource blocks are configured by delay-Doppler resource blocks. how it works. 11. The method of claim 10,
The method of operation of the first communication node,
Before the step of demodulating the multi-carrier,
performing, with the second communication node, a signaling procedure for information on sizes of the N first spreading resource blocks on the first 2D domain and the N second spreading resource blocks on the second 2D domain Further comprising, the method of operation of the first communication node. 14. The method of claim 13,
The step of performing the signaling procedure,
Receiving, from the second communication node providing a communication service to the first communication node, signaling on information on sizes of the N first spreading resource blocks and the N second spreading resource blocks , a method of operation of the first communication node. 14. The method of claim 13,
The step of performing the signaling procedure,
Signaling information on sizes of the N first spreading resource blocks and the N second spreading resource blocks to one or more communication nodes including the second communication node from which the first communication node provides a communication service A method of operating a first communication node, comprising the steps of. 14. The method of claim 13,
The step of performing the signaling procedure,
performing, with the second communication node, a signaling procedure on information of candidates having sizes of the N first spreading resource blocks and the N second spreading resource blocks; and
performing, with the second communication node, a signaling procedure on information indicating any one of the candidates of the size of the N first spreading resource blocks and the N second spreading resource blocks , a method of operation of the first communication node. 11. The method of claim 10,
The method of operation of the first communication node,
After the step of demapping from the N first spreading resource blocks,
performing channel equalization in the first 2D domain on the data symbols demapped from the N first spreading resource blocks;
The data symbols demapped from the N first spreading resource blocks that are post-processed in the post-processing are demapped from the N first spreading resource blocks to achieve channel equalization in the first 2D domain. A method of operation of a first communication node, which is coarse data symbols. 18. The method of claim 17,
The step of performing channel equalization on the first 2D domain includes:
performing channel estimation on the first 2D domain;
calculating a channel equalization coefficient on the first 2D domain based on a result of channel estimation on the first 2D domain; and
and performing channel equalization on the first 2D domain based on the calculated channel equalization coefficient on the first 2D domain. 11. The method of claim 10,
Obtaining the first codeword comprises:
performing channel equalization in the second 2D domain on the data symbols sequentially demapped from the N second spreading resource blocks; and
and obtaining the first codeword based on data symbols that have undergone channel equalization in the second 2D domain. 11. The method of claim 10,
The method of operation of the first communication node,
Before the step of demodulating the multi-carrier,
The method of operating a first communication node, further comprising transmitting a terminal capability report related to channel equalization on at least one of the first 2D domain and the second 2D domain to the second communication node. A method of operating a first communication node in a communication system, the method comprising:
The radio signals received from the second communication node of the communication system are received for each of the plurality of resources included in N first spreading resource blocks configured to include a plurality of resources, respectively, in a first two-dimensional (2D) domain. multi-carrier demodulation;
identifying data symbols mapped to each of the N first spreading resource blocks based on a result of the multi-carrier demodulation;
demapping the data symbols mapped to each of the N first spreading resource blocks from the N first spreading resource blocks;
Post-processing (despreading) the demapped data symbols from the N first spreading resource blocks for each of N second spreading resource blocks configured to include a plurality of resources in a second 2D domain ( postprocessing);
demapping the post-processed data symbols from the N second spreading resource blocks;
For the data symbols demapped from the N second spreading resource blocks, channel estimation results for each of the N second spreading resource blocks based on reference signals mapped to the N second spreading resource blocks. performing channel equalization on the second 2D domain based on and
obtaining a first codeword based on the data symbols subjected to channel equalization in the second 2D domain;
Wherein N is a natural number, the operating method of the first communication node.

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