KR102594859B1 - Apparatus and method for transmitting and receiving signal in wireless communication system - Google Patents

Abstract

The present invention is a 5th generation (5G) or free communication system provided to support higher data rates after the ^4th generation (4G) communication system such as long ^term evolution (LTE). -It is related to 5G (pre-5G) communication system.
The present invention relates to a method of operating a transmitting device in a wireless communication system, comprising: a second receiving device pairing with the first receiving device when a sliding window superposition coding method is applied to the first receiving device; First information indicating whether a non-orthogonal multiple access (NOMA) method is applied to the second receiving device, and second information that is information related to the NOMA method when the NOMA method is applied to the second receiving device. It is characterized by including a process of transmitting to a first receiving device.

Description

Device and method for transmitting/receiving signals in a wireless communication system {APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING SIGNAL IN WIRELESS COMMUNICATION SYSTEM}

The present invention relates to an apparatus and method for transmitting/receiving signals in a wireless communication system, and particularly to a non-orthogonal multiple access (NOMA) method and sliding window overlap coding (sliding window overlap coding). This relates to a device and method for transmitting/receiving signals based on window superposition coding (SWSC, hereinafter referred to as "SWSC").

In order to meet the increasing demand for wireless data traffic following the commercialization of the 4th generation ( ^4th generation: 4G, hereinafter referred to as “4G”) communication system, an improved 5th generation ( ^5th generation: 5G, hereinafter “) Efforts are being made to develop a communication system (hereinafter referred to as "5G") or a pre-5G (hereinafter referred to as "pre-5G") communication system. For this reason, the 5G communication system or pre-5G communication system is a communication system beyond 4G network or a post-LTE system after long-term evolution (LTE, hereinafter referred to as 'LTE'). It is called.

To achieve high data rates, 5G communication systems are being considered for implementation in ultra-high frequency (mmWave) bands (e.g., frequency bands such as the 60 gigahertz (60GHz) band). In order to alleviate the path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, the 5G communication system uses beam forming and massive multi-input multi-output (massive MIMO, hereinafter referred to as "massive multi-input multi-output"). (hereinafter referred to as "massive MIMO") technology, full dimensional MIMO (FD-MIMO, hereinafter referred to as "FD-MIMO") technology, array antenna technology, and analog Beam forming (analog beam-forming) technology and large scale antenna technology are being discussed.

In addition, to improve the network of the system, the 5G communication system uses advanced small cells, advanced small cells, cloud radio access networks (cloud RAN), and ultra-dense networks. , device to device (D2D) communication, wireless backhaul, moving network, cooperative communication, CoMP (coordinated multi-points) , and interference cancellation technologies are being developed.

In addition, in the 5G system, hybrid frequency shift keying (FSK), which is an advanced coding modulation (ACM) method, and orthogonal Amplitude modulation (QAM, hereinafter referred to as "QAM") (hybrid FSK and QAM: FQAM, hereinafter referred to as "FQAM") method and SWSC method, and filter bank multi-carrier (hereinafter referred to as "FQAM"), which is an advanced access technology. Filter bank multi carrier (FBMC, hereinafter referred to as "FBMC") technology, NOMA technology, and sparse code multiple access (SCMA, hereinafter referred to as "SCMA") technology are being developed.

In a network based on orthogonal multiple access (OMA), the same resources are provided to multiple user equipment (UE). It is not allocated, but rather assigned to a single user terminal. Here, the resources may be time resources, frequency resources, etc. Accordingly, a base station (evolved node B: eNB, hereinafter referred to as “eNB”) allocates resources to UEs that can maximize channel capacity based on the channel environment and resource allocation frequency of each UE.

Therefore, UEs located in a specific area, such as a cell border area, have relatively less opportunity to be allocated resources compared to other UEs that are not located in the specific area, and thus issues of fairness between UEs may arise. You can.

Meanwhile, in a network based on the NOMA method, the same resources are allocated to multiple UEs, thereby increasing resource efficiency. In addition, in a network based on the NOMA method, interference issues between UEs allocated to the same resources are resolved through cooperation between eNBs and UEs, thereby increasing the average throughput for eNBs and increasing the average throughput in specific areas such as cell boundary areas. Increases resource allocation opportunities for located UEs.

For example, in a network based on the power domain NOMA (hereinafter referred to as “power domain NOMA”) method, the same resources are allocated to UEs located near the eNB and UEs located in the cell boundary area. do. In addition, the transmission power allocated to the UE located near the eNB is reduced, and the same amount of transmission power as the reduced transmission power to the UE located near the eNB is additionally allocated to the UE located in the cell boundary area. .

When the transmission power for UEs is adjusted in this way, the UE located near the eNB has a signal strength greater than the strength of the signal transmitted by the eNB to the UE itself located near the eNB, and the eNB is located in the cell boundary area. A signal transmitted to the UE located at is received, that is, an interference signal.

Accordingly, the UE located near the eNB first detects the signal transmitted by the eNB to the UE located in the cell boundary area, that is, the interference signal, from the received signal. Then, after removing the detected interference signal from the received signal, a signal targeting the UE itself located near the eNB, that is, a target signal, is detected.

In this case, a UE located near the eNB can significantly reduce the impact of interference signals caused by the eNB's overlapping transmission. In addition, the UE located in the cell border area transmits a signal transmitted by the eNB to the UE itself located in the cell border area, that is, the transmission power of the target signal is a signal transmitted to the UE located near the eNB, that is, an interference signal. Since it is much larger than the transmission power of , it is hardly affected by the interference signal.

Meanwhile, in a network based on orthogonal frequency division multiple access (OFDMA), hereinafter referred to as "OFDMA"), inter-cell interference signals are inevitably generated, which are located in the cell boundary area. This may cause relatively large performance degradation to the user terminal.

If, in a network based on the NOMA method, the same resources are allocated to a UE located near an eNB and a UE located in a cell boundary area that is significantly affected by interference signals between cells, and the UE located near the eNB and the cell If the transmission power is adjusted to solve the problem of interference between UEs located in the border area, the eNB allocates relatively large transmission power to the UEs located in the cell border area, which are greatly affected by inter-cell interference signals, resulting in Relatively small transmission power is allocated to UEs located near the eNB.

This results in relatively large performance degradation for UEs located near the eNB. Therefore, in a network based on the NOMA method, reducing the impact of inter-cell interference signals on UEs located in the cell border area can be a very important issue.

Meanwhile, the above information is presented only as background information to aid understanding of the present invention. No decision has been made, and no claim is made, as to whether any of the above is applicable as prior art with respect to the present invention.

An embodiment of the present invention proposes an apparatus and method for transmitting/receiving signals based on the NOMA method and SWSC method in a wireless communication system.

Additionally, an embodiment of the present invention proposes a signal transmission/reception device and method for reducing interference based on the NOMA method and SWSC method in a wireless communication system.

Additionally, an embodiment of the present invention proposes a signal transmission/reception device and method for improving performance based on the NOMA method and SWSC method in a wireless communication system.

A method according to an embodiment of the present invention; In a method of operating a transmitting device in a wireless communication system, when a sliding window superposition coding method is applied to a first receiving device, a ratio is applied to a second receiving device paired with the first receiving device. The first receiving device receives first information indicating whether a non-orthogonal multiple access (NOMA) method is applied, and second information that is information related to the NOMA method when the NOMA method is applied to the second receiving device. It is characterized by including a process of transmitting to a device.

Another method according to an embodiment of the present invention is; In a method of operating a receiving device in a wireless communication system, from a transmitting device, to a first receiving device paired with the receiving device when a sliding window superposition coding method is applied to the receiving device. A process of receiving first information indicating whether a non-orthogonal multiple access (NOMA) method is applied, and second information that is information related to the NOMA method when the NOMA method is applied to the first receiving device. It is characterized by including.

Another method according to an embodiment of the present invention is; In a method of operating a receiving device in a wireless communication system, a sliding window overlaps from a transmitting device to a first receiving device that is paired with the receiving device based on a non-orthogonal multiple access (NOMA) method. It is characterized by comprising the process of receiving first information indicating whether a coding (sliding window superposition coding) method is applied and second information that is information related to the SWSC method.

Other aspects, benefits and essential features of the invention will become apparent to those skilled in the art from the following detailed description, taken together with the accompanying drawings and disclosing preferred embodiments of the invention.

Before proceeding with the specific description portion of the present disclosure below, it may be useful to establish definitions for certain words and phrases used throughout this patent document: the terms "include" and " “comprise” and its derivatives mean unlimited inclusion; The term “or” is inclusive and means “and/or”; The above phrases “associate with” and “associate therewith” and their derivatives include, be included within, and are interconnected with ( interconnect with, contain, be contained within, connect to or with, couple to or with ), be communicable with, cooperate with, interleave, juxtapose, be proximate to, and have the potential to It means things like being bound to or with, having, having a property of, etc.; The term "controller" means any device, system, or part thereof that controls at least one operation, and such device may be hardware, firmware, or software, or some combination of at least two of the hardware, firmware, or software. It can be implemented in . It should be noted that the functionality associated with any particular controller may be centralized or distributed, and may be local or remote. Definitions of certain words and phrases are provided throughout this patent document, and those skilled in the art will recognize that in many, if not most, cases, such definitions may be found in the prior art as well as words and phrases defined as above. It should be understood that this also applies to future uses of the phrases.

An embodiment of the present invention makes it possible to transmit/receive signals based on the NOMA method and SWSC method in a wireless communication system.

Additionally, an embodiment of the present invention makes it possible to transmit/receive signals to reduce interference based on the NOMA method and SWSC method in a wireless communication system.

Additionally, an embodiment of the present invention makes it possible to transmit/receive signals to improve performance based on the NOMA method and SWSC method in a wireless communication system.

The above-described and other aspects, features and benefits of certain preferred embodiments of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings:
1 is a diagram schematically showing an interference environment to which the SWSC method is applied in a wireless communication system according to an embodiment of the present invention;
Figure 2 is a diagram schematically showing transmission and reception operations according to the SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 3 is a diagram schematically showing signal transmission/reception operations according to the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 4 is a diagram schematically showing the internal structure of a transmission device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 5 is a diagram schematically showing the operation process of a receiving device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 6 is a diagram schematically showing the operation process of a near UE in a wireless communication system supporting the power domain NOMA-SWSC method according to an embodiment of the present invention;
Figure 7 is a diagram schematically showing the operation process of a far UE in a wireless communication system supporting the power domain NOMA-SWSC method according to an embodiment of the present invention;
Figure 8 is a diagram schematically showing signal transmission/reception operations according to the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 9 is a diagram schematically showing the internal structure of a transmission device supporting the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 10 is a diagram schematically showing an example of an operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method according to an embodiment of the present invention;
Figure 11 is a diagram schematically showing another example of the operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method according to an embodiment of the present invention;
Figure 12 is a diagram schematically showing signal transmission/reception operations according to the IDMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 13 is a diagram schematically showing the internal structure of a transmission device supporting the IDMA-SWSC method in a wireless communication system according to an embodiment of the present invention;
Figure 14 is a diagram schematically showing the operation process of a signal reception device in a wireless communication system supporting the IDMA-SWSC method according to an embodiment of the present invention.
It should be noted that throughout the drawings, like reference numerals are used to illustrate identical or similar elements, features and structures.

The following detailed description with reference to the accompanying drawings will assist in comprehensively understanding the various embodiments of the present disclosure, as defined by the claims and their equivalents. The following detailed description includes numerous specific details to aid understanding, but is to be regarded merely as an example. Accordingly, those skilled in the art will recognize that various changes and modifications to the various embodiments described herein may be made without departing from the scope and spirit of the present disclosure. Additionally, descriptions of well-known functions and configurations may be omitted for clarity and brevity.

The terms and words used in the following detailed description and claims are not limited to their literary meanings, but are simply used to enable a clear and consistent understanding of the present disclosure by the inventor. Accordingly, to those skilled in the art, the following detailed description of various embodiments of the present disclosure is provided for illustrative purposes only and does not limit the disclosure to the extent defined by the appended claims and their equivalents. It should be clear that it is not provided to do so.

Additionally, it will be understood that singular expressions such as “unless” and “the” include plural expressions in this specification, unless otherwise clearly indicated. Thus, in one example, a “component surface” includes one or more component representations.

Additionally, terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component, and similarly, the second component may also be named a first component without departing from the scope of the present invention. The term and/or includes any of a plurality of related stated items or a combination of a plurality of related stated items.

Additionally, the terms used in this specification are only used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to indicate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Additionally, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms as defined in commonly used dictionaries should be understood to have meanings consistent with their meanings in the context of the relevant technology.

According to various embodiments of the present invention, an electronic device may include communication functionality. For example, electronic devices include smart phones, tablet personal computers (PCs), mobile phones, video phones, and e-book readers (e-book readers). -book reader, desktop PC, laptop PC, netbook PC, personal digital assistant (PDA, hereinafter referred to as 'PDA'), and portable A portable multimedia player (PMP, hereinafter referred to as 'PMP'), an mp3 player, a mobile medical device, a camera, and a wearable device (e.g., a head-mounted device) A head-mounted device (HMD, for example, hereinafter referred to as 'HMD'), electronic clothing, electronic bracelet, electronic necklace, electronic accessory, electronic tattoo, or smart watch. ), etc.

According to various embodiments of the present invention, an electronic device may be a smart home appliance having a communication function. As an example, the smart home device includes a television, a digital video disk (DVD) player, an audio device, a refrigerator, an air conditioner, a vacuum cleaner, an oven, and Microwave ovens, washers, dryers, air purifiers, set-top boxes, TV boxes (e.g. Samsung HomeSync ^TM , Apple TV ^TM , or Google TV ^TM ), and game consoles It can be a gaming console, an electronic dictionary, a camcorder, an electronic photo frame, etc.

According to various embodiments of the present invention, the electronic device may include a medical device (e.g., a magnetic resonance angiography (MRA) device, hereinafter referred to as 'MRA'), and a magnetic resonance imaging (MRA) device. : MRI (hereinafter referred to as “MRI”), computed tomography (CT, hereinafter referred to as “CT”) device, imaging device, or ultrasound device), navigation device, and , a global positioning system (GPS, hereinafter referred to as 'GPS') receiver, an event data recorder (EDR, hereinafter referred to as 'EDR'), and a flight data recorder (flight data). recorder: FDR, hereinafter referred to as 'FER'), automotive infotainment device, navigation electronic device (e.g., nautical navigation device, gyroscope, or compass), and avionics device Wow, it could be a security device, an industrial or consumer robot, etc.

According to various embodiments of the present invention, electronic devices include furniture, parts of buildings/structures, electronic boards, electronic signature receiving devices, projectors, and various measurement devices (e.g., including communication functions). This could be water, electricity, gas or electromagnetic wave measurement devices).

According to various embodiments of the present invention, the electronic device may be a combination of devices as described above. Additionally, it will be apparent to those skilled in the art that electronic devices according to preferred embodiments of the present invention are not limited to the devices described above.

According to various embodiments of the present invention, the signal receiving device may be a user equipment (UE), for example, and the signal transmitting device may be, for example, an evolved node ratio. node B: may be an eNB, hereinafter referred to as “eNB”).

In various embodiments of the present invention, UE is used interchangeably with terms such as mobile station (MS), wireless terminal, mobile device, etc. It can be.

In various embodiments of the present invention, eNB includes terms such as base station (BS), node B, access point (AP), etc. Can be used interchangeably.

One embodiment of the present invention is a non-orthogonal multiple access (NOMA, hereinafter referred to as "NOMA") method and sliding window superposition coding (SWSC) in a wireless communication system. We propose a device and method for transmitting/receiving signals based on the method (hereinafter referred to as ).

Additionally, an embodiment of the present invention proposes a signal transmission/reception device and method for reducing interference based on the NOMA method and SWSC method in a wireless communication system.

Additionally, an embodiment of the present invention proposes a signal transmission/reception device and method for improving performance based on the NOMA method and SWSC method in a wireless communication system.

Meanwhile, the device and method proposed in an embodiment of the present invention are a long-term evolution (LTE) mobile communication system and a long-term evolution-advanced (long-term evolution) mobile communication system. -advanced: LTE-A, hereinafter referred to as “LTE-A”) mobile communication system, and licensed-assisted access (LAA, hereinafter referred to as “LAA”)-LTE mobile communication system , high speed downlink packet access (HSDPA, hereinafter referred to as “HSDPA”) mobile communication system, and high speed uplink packet access (HSUPA, hereinafter referred to as “HSUPA”) ) A mobile communication system and high rate packet data (HRPD, hereinafter referred to as “HRPD”) of the 3rd generation partnership project 2 (3GPP2, hereinafter referred to as “3GPP2”) ) A mobile communication system, a 3GPP2 wideband code division multiple access (WCDMA, hereinafter referred to as “WCDMA”) mobile communication system, and a 3GPP2 code division multiple access (code division multiple access: CDMA) , hereinafter referred to as "CDMA") mobile communication system, Institute of Electrical and Electronics Engineers (IEEE, hereinafter referred to as "IEEE") 802.16m communication system, and IEEE 802.16e communication system. and, an evolved packet system (EPS, hereinafter referred to as “EPS”), a mobile internet protocol (mobile internet protocol: Mobile IP, hereinafter referred to as “Mobile IP”) system, and digital multimedia. Broadcasting (digital multimedia broadcasting, hereinafter referred to as "DMB") services, portable digital video broadcasting-handheld (DVP-H, hereinafter referred to as "DVP-H"), and mobile/portable evolution. Mobile broadcasting services such as advanced television systems committee-mobile/handheld (ATSC-M/H, hereinafter referred to as "ATSC-M/H") services, and Internet protocol television (IPTV) , hereinafter referred to as "IPTV") services, digital video broadcasting systems, and various communications such as the moving picture experts group (MPEG) media transport (MMT) system, etc. Applicable to systems.

First, with reference to FIG. 1, the interference environment to which the SWSC method is applied in a wireless communication system according to an embodiment of the present invention will be described.

Figure 1 is a diagram schematically showing an interference environment to which the SWSC method is applied in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 1, the SWSC method is a method that can reduce the influence of interference signals from adjacent cells in a cellular network. In the wireless communication system, eNB #1 (100) manages cell #1 (110), eNB #2 (101) manages cell #2 (111), and eNB #3 (102) manages cell #3 ( 112) is managed.

In addition, UE #1 (120) receives signals transmitted by eNB #1 (100) and eNB #3 (102), and UE #2 (121) receives signals transmitted by eNB #2 (101). receives. At this time, the UE #2 (121) receives not only the signal transmitted by the eNB #2 (101) but also the signal transmitted by each of the eNB #1 (100) and eNB #3 (102), and the eNB Signals transmitted by each of #1 (100) and eNB #3 (102) act as interference to UE #2 (121).

In Figure 1, the interference environment in which the SWSC method is applied in the wireless communication system according to an embodiment of the present invention is explained. Next, with reference to Figure 2, the interference environment according to the SWSC method in the wireless communication system according to an embodiment of the present invention is explained. Transmission and reception operations will now be described.

Figure 2 is a diagram schematically showing transmission and reception operations according to the SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 2, first, in FIG. 2, two signal transmission devices, for example, two eNBs and two signal reception devices, for example, two UEs, perform transmission and reception operations according to the SWSC method. As an example, transmission and reception operations according to the SWSC method are described, but depending on network coordination, one or more signal transmission devices and/or one or more signal reception devices transmit and receive according to the SWSC method. Of course, you can also participate in the movement. Additionally, in Figure 2, it is assumed that the same message is transmitted through two blocks and the window size is 2.

Referring to FIG. 2, first assume that the signals transmitted by two eNBs, for example, S1 (210) and S2 (215), are X ₁ and X ₂ , respectively, and that two UEs, for example, R1 (220) ), it is assumed that the signals received by R2 (225) are Y ₁ and Y ₂ , respectively. In each block 205, the eNB S1 (210) codes the message to be transmitted according to an overlap coding method using two codes U and V to generate _a signal Generate a signal X ₂ containing a message. Here, each message to be transmitted may be, for example, at least one packet or protocol data unit (PDU) (hereinafter referred to as “PDU”).

Specifically, in block 1, the eNB S1 (210) sends a message known to both the eNB S1 (210) and the UEs (for convenience, shown as “1” in FIG. 2) to U. A codeword U(1) is generated by coding based on the code, and the message m ₁₁ to be transmitted in block 1 is coded based on the code V to generate a codeword V(1). Then, the eNB S1 (210) outputs the _codeword A signal containing the _codeword In addition, in block 1 _, the eNB _S2 ( ₂₁₅ ) outputs a codeword do.

Additionally, in block 2, the eNB S1 (210) codes the previously transmitted message m ₁₁ based on the code U to generate a codeword U(2), and generates a codeword U(2) to be transmitted in block 2. Codeword V(2) is generated by coding message m ₂₂ with code V, and codeword X ₁ (2) is generated by overlapping coding of U(2) and V(2). Then, the eNB S1 ( ₂₁₀ ) transmits the generated codeword In block 2, the eNB _{S2 215} transmits a codeword

In this way, messages are transmitted for (b-1) blocks, and in the last block, block b, the eNB S1 210 sends the previously transmitted message m _{1,b -1} with the code U. A codeword U(b) is generated by coding based on the known message "1" and a codeword V(b) is generated by coding the known message "1" based on the code V, and the U(b) and V(b) are generated. The codeword X ₁ (b) generated by overlapping coding is transmitted. In block b, the eNB S2 215 transmits a codeword X ₂ (b) including the message m _2b to be transmitted.

The above described an example in which two codes, that is, code U and code V, overlap, and the transmission signal of transmitter S1 (210) is generated by X ₁ =f(U,V), and each UE has two blocks A sliding window decoding operation can be performed using signals received while overlapping. That is, UE R1 cancels the codeword U(1) using the known message “1” based on the received signals Y ₁ (1) and Y ₁ (2) of blocks 1 and 2, By considering V(1) as noise, X ₂ (1), which is interference to the UE R1, is detected.

Next, _the UE R1 removes U(1) from the received signals using the known message “ ₁ ”, removes the detected signal By considering 2) as noise, the desired signal [V(1) U(2)] is detected. Message m ₁₁ can be restored from the detected signal.

Likewise, when the received signal Y ₁ (3) of block 3 arrives, the UE R1 uses the previously detected codeword U (2) instead of the known message “1” to perform the same operations as described in blocks 1 and 2 above. The desired message m ₁₂ can be restored by repeating an operation similar to . That is, because the codeword U(2) has already been detected in block 2, U(2) operates as a known message in block 3.

Likewise, in subsequent blocks the UE R1 can detect desired messages. When the received signal Y ₁ (b) arrives in block b, which is the last block, the UE R1 removes U(b-1) using the previously detected codeword U(b-1) and returns the known message “1” By removing V(b) using , the desired signal [V(b-1) U(b)] is detected and the message m _{1,b -1} is restored.

The UE R2 detects the desired signal of UE 1 as an interference signal in a similar manner to UE R1, and detects the desired signal of UE R2 by removing the detected interference signal from received signals.

Specifically, when overlapping received signals Y ₂ (1) and Y ₂ (2) are input through blocks 1 and 2, the UE R2 removes the codeword U (1) using the known message “1”. And, by considering X _{2 (} 1), _V (2) and (For convenience, the restored message m ₁₁ is indicated as hat_m ₁₁ in FIG. 2). In the next step, the UE R2 uses the message "1" known from the received signals to remove V(1) detected in the previous block using the message m ₁₁ and then detects X ₂ (1) to generate message m ₂₁ Restore .

Likewise, in subsequent blocks, the UE R2 can detect desired messages. When the received signal Y ₁ (b) arrives in block b, which is the last block, the UE R2 uses the previously detected codeword V (b) to perform a decoding operation on the received signals of the two most recent blocks. .

To operate the SWSC method in a cellular environment, one of the eNBs or a separate network entity (not shown) may operate as a coordinator. The coordinator performs a co-scheduling operation between eNBs, determines a UE pair to apply the overlap coding scheme in consideration of the capacity region, and determines the UE pair to apply to the transmitted packets. It provides signaling information about the SWSC method and can control feedback operations and retransmission operations for SWSC transmission.

Meanwhile, the SWSC method described above can obtain theoretical critical performance in the physical layer in an additive white Gaussian noise (AWGN) interference environment without fading. This coding method shows relatively high efficiency.

However, since the SWSC method does not consider overlapping transmission between UEs within a cell, it may be difficult to obtain performance gains when using the SWSC method in a wireless communication system supporting the NOMA method.

Therefore, an embodiment of the present invention proposes a device and method for transmitting/receiving signals by efficiently combining the NOMA method and the SWSC method, which will be described in detail as follows.

First, in an embodiment of the present invention, for example, there are three NOMA methods, namely, a power domain NOMA (power domain NOMA) method, and an interleaver division multiple access (interleaver division multiple access) method. We will consider the IDMA (hereinafter referred to as "IDMA") method and the sparse code multiple access (SCMA) method. For convenience of explanation, the method combining the power domain NOMA method and the SWSC method will be referred to as the "power domain NOMA-SWSC method", and the method combining the IDMA method and the SWSC method will be referred to as the "IDMA-SWSC method", and the SCMA method The method that combines the method and the SWSC method will be referred to as the “SCMA-SWSC method.” Additionally, in one embodiment of the present invention, the low density signature-OFDM (LDS-OFDM) method may be used instead of the SCMA method.

First, the power domain NOMA-SWSC method in the wireless communication system according to an embodiment of the present invention will be described.

First, with reference to FIG. 3, signal transmission/reception operations according to the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention will be described.

Figure 3 is a diagram schematically showing signal transmission/reception operations according to the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 3, the wireless communication system includes a plurality of eNBs, for example, two eNBs, for example, eNB #1 (310) and eNB #2 (320), and a plurality of UEs, for example, three UEs, for example, include UE#1 (331), UE#2 (332), and UE#3 (333). Here, it is assumed that the reference UE is the UE#1 (331), and therefore, the eNB#1 (310) becomes the serving eNB for the UE#1 (331), and the eNB#2 (320) becomes an interfering eNB that transmits an interference signal to the UE #1 (331).

In addition, the UE #1 (331) and UE #2 (332) are NOMA paired UEs (hereinafter referred to as “NOMA paired UE”) paired based on the NOMA method, The UE#1 (331) and UE#3 (333) are SWSC paired UEs (hereinafter referred to as “SWSC paired UE”) paired based on the SWSC method. That is, the UE#1 (331) and UE#2 (332) form a NOMA pair (hereinafter referred to as “NOMA pair”), and the UE#1 (331) and UE#3 (333) form a NOMA pair (hereinafter referred to as “NOMA pair”). A SWSC pair (hereinafter referred to as “SWSC pair”) is formed.

In order to support the power domain NOMA-SWSC method according to an embodiment of the present invention, the structure and operation process of each signal transmitting device, such as an eNB and a signal receiving device, such as UE, must be changed. This will be described in detail. As follows.

First, the structure and operation process of an eNB supporting the power domain NOMA-SWSC method according to an embodiment of the present invention will be described as follows.

First, the eNB must reflect the SWSC encoder output characteristics in the general power domain NOMA method. That is, the SWSC encoder output must be detected at UE#2 (332), which is a UE (near UE, hereinafter referred to as “near UE”) adjacent to eNB #1 (310), which is the serving eNB, and the eNB # When performing a SWSC decoding operation at UE #1 (331), which is a distant UE (hereinafter referred to as “far UE”) from 1 (310), the signal strength for UE #2 (332) is very high. It must be small, for example, to have an intensity below a critical intensity. In one embodiment of the present invention, the case where near UE and far eNB are set based on the distance from the eNB has been described as an example, but near UE and far eNB may be set considering various parameters as well as the distance from the eNB. Of course, it exists, and its detailed description will be omitted here. As an example, a far eNB may be a UE located in a cell border area.

Therefore, the eNB must determine UE pairing, parameter b, and modulation order considering the conditions described above, and must also change the scheduling process for UEs. Here, the parameter b represents a parameter used for the power domain NOMA method, and as an example, the transmission power split coefficient (transmission power split), which is the ratio of the transmission power of the UE with relatively excellent channel quality among the transmission power for the overlapping signal. coefficient: TPSC, hereinafter referred to as “TPSC”). Here, the remaining UEs excluding the UE are included in a UE pair according to the power domain NOMA method, that is, a power domain NOMA pair.

Next, a signal receiving device, for example, a UE, must reflect the SWSC decoding operation in the general power domain NOMA method. That is, a UE that supports the power domain NOMA-SWSC method, which combines the SWSC method and the power domain NOMA method, must apply the power domain NOMA decoding operation when performing the SWSC decoding operation.

Therefore, in the power domain NOMA-SWSC method according to an embodiment of the present invention, the eNB must provide the following information to the UE.

First, the information provided to far UE is as follows.

(1) When the SWSC method is applied to the far UE, information indicating whether the power domain NOMA method is applied to the UE paired with the far UE based on the SWSC method.

In Figure 3, the far UE is UE#1 (331), and the UE paired with UE#1 (331) based on the SWSC method is UE#3 (333).

(2) When the power domain NOMA method is applied to a UE paired with a far UE, information about the power domain NOMA method applied to the UE paired with the far UE

The reception operation when the power domain NOMA method is applied to a UE paired with a far UE will be described below with reference to FIG. 5, so detailed description will be omitted here.

Second, the information provided to near UE is as follows.

(1) Information indicating whether to apply the SWSC method to far UE

(2) When the SWSC method is applied to far UE, information related to sliding window

Information related to the sliding window may include a length over which the sliding window overlaps and a parameter a. Here, parameter a represents the weight factor used in the SWSC method.

The information provided to the near UE may affect the near UE's ability to detect signals for the far UE and estimate the modulation order applied to the far UE.

Meanwhile, the scheduling method according to the power domain NOMA-SWSC method according to an embodiment of the present invention will be described as follows.

Before explaining the scheduling method according to the power domain NOMA-SWSC method according to an embodiment of the present invention, the scheduling method according to the general power domain NOMA method is described as follows.

First, the eNB considers all candidate power ratios, modulation and coding scheme (MCS) levels for UEs in the cell, and determines capacity (or the capacity). Select the power domain NOMA pair with the highest throughput calculated based on a similar metric.

Meanwhile, in the scheduling method according to the power domain NOMA-SWSC method according to an embodiment of the present invention, the eNB considers both the candidate power ratio and MCS level for UEs in the cell and UE candidates to apply the SWSC method, Select the power domain NOMA-SWSC pair with the highest throughput calculated based on capacity (or a metric similar to the above capacity). For example, for a far UE, a power domain NOMA-SWSC pair is created so that the near UE's signal can be received at a strength less than the threshold strength. This is to satisfy the condition of a high signal to noise ratio (SNR, hereinafter referred to as “SNR”) when applying the SWSC method.

Then, with reference to FIG. 4, the internal structure of a transmission device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention will be described.

Figure 4 is a diagram schematically showing the internal structure of a transmission device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 4, first, a transmitting device, for example, an eNB, includes a SWSC encoder 410, an adder 420, a turbo encoder 430, a modulator 440, and a symbol generator 450. Includes. Here, the modulator 440 is based on quadrature amplitude modulation (QAM, hereinafter referred to as “QAM”).

In addition, the SWSC encoder 410 includes a plurality of short turbo encoders, such as short turbo encoder #1 (411-1), short turbo encoder #2 (411-2), etc., and a plurality of modulators. , for example, modulator #1 (413-1), modulator #2 (413-2), etc., a delay unit (415), and a number of adders, for example, adder #1 (417-1) and adder #2 (417-2), etc., and a symbol generator (419). The plurality of modulators perform modulation operations based on the QAM method.

In Figure 4, parameter a represents a weight coefficient used in the SWSC method, and parameter b is a parameter used in the power domain NOMA method, and represents TPSC as an example, and detailed descriptions of the parameters a and parameter b will be omitted. do.

A signal to be transmitted to a far UE, for example, UE#1, is input to the SWSC encoder 410, and thus the signal is input to the plurality of short turbo encoders, and the plurality of short turbo encoders each transmit the signal. It is encoded according to the short turbo encoding method, and the encoded signal is output to each of the plurality of modulators.

The plurality of modulators each modulate the signal output from the corresponding short turbo encoder according to the QAM method. Then, the modulator #1 (413-1) outputs the modulated signal to the adder #1 (417-1), and the modulator #2 (413-2) outputs the modulated signal to the delay unit ( 415). The delay unit 415 delays the signal output from the modulator #2 (413-2) by a preset time and then outputs it to the adder #2 (417-2).

The plurality of adders each perform an addition operation corresponding to parameter a and then output the added signal to the symbol generator 419. The symbol generator 419 generates a symbol for UE #1, that is, a QAM symbol, and outputs it to the adder 420.

Meanwhile, a signal to be transmitted to a near UE, for example, UE #2, is input to the turbo encoder 430, and the turbo encoder 430 encodes the signal corresponding to the turbo encoding method and converts the encoded signal into It is output to the modulator 440. The modulator 440 modulates the signal output from the turbo encoder 430 according to the QAM method and outputs the modulated signal to the symbol generator 450. The symbol generator 450 generates a symbol for UE#2, that is, a QAM symbol, and outputs it to the adder 420.

The adder 420 adds the signal output from the symbol generator 419 and the signal output from the symbol generator 450 based on parameter b to generate a serving eNB signal, and the serving eNB signal is transmitted to UEs, That is, it is transmitted to UE#1 and UE#2.

Meanwhile, Figure 4 shows a case where the SWSC encoder 410, the adder 420, the turbo encoder 430, the modulator 440, and the symbol generator 450 are implemented as separate units. Of course, at least two of the SWSC encoder 410, adder 420, turbo encoder 430, modulator 440, and symbol generator 450 can be integrated. In addition, of course, the SWSC encoder 410, the adder 420, the turbo encoder 430, the modulator 440, and the symbol generator 450 may be implemented with one processor.

In FIG. 4, the internal structure of a transmitting device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention is explained. Next, with reference to FIG. 5, the wireless communication system according to an embodiment of the present invention is described. We will now explain the operation process of a receiving device that supports the power domain NOMA-SWSC method in a communication system.

Figure 5 is a diagram schematically showing the operation process of a receiving device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 5, it should be noted that the operation process of the receiving device shown in FIG. 5 is the operation process of a UE existing in the same environment as UE #1 (331) shown in FIG. 3.

First, when a transmitting device, for example, an eNB, transmits based on the power domain NOMA-SWSC method, UE#1 receives the UE#1 signal, which is a signal targeting UE#1, and the UE#1 and power domain NOMA pair The UE#2 signal, which is a signal targeting UE#2 constituting , and the UE#3 signal, which is a signal targeting UE#3 constituting the UE#1 and SWSC pair, are received together. Here, the UE#3 signal acts as a downlink interference (DI) signal for the UE#1. Additionally, since the SWSC method is applied to the UE#1 signal and the UE#3 signal, it can be seen that the UE#1 signal and the UE#3 signal are generated by overlapping multiple signals based on the weight coefficient.

Therefore, the UE#1 performs a decoding operation corresponding to the power domain NOMA method for the UE#1 signal and the UE#2 signal, and decoding corresponding to the SWSC method for the UE#1 signal and the UE#3 signal. Perform the action. In addition, the decoding operation of the UE #1 includes information provided by the eNB, that is, information indicating whether the power domain NOMA method is applied to the UE #3, that is, the UE paired with the UE #1 in the SWSC encoding method. , When the power domain NOMA method is applied to UE #3, it is performed based on information about the applied power domain NOMA method.

In Figure 5, the operation process of a receiving device supporting the power domain NOMA-SWSC method in a wireless communication system according to an embodiment of the present invention is explained. Next, with reference to Figure 6, the power signal according to an embodiment of the present invention is explained. We will now explain the operation process of near UE in a wireless communication system supporting the domain NOMA-SWSC method.

Figure 6 is a diagram schematically showing the operation process of a near UE in a wireless communication system supporting the power domain NOMA-SWSC method according to an embodiment of the present invention.

Referring to FIG. 6, first, the near UE receives information indicating whether the SWSC method is applied to the far UE from a transmitting device, for example, an eNB, and information related to the sliding window when the SWSC method is applied to the far UE.

In addition, the operation process of the near UE shown in FIG. 6 is the operation process of a UE existing in the same environment as UE #2 (332) shown in FIG. 3, and the signal that the near UE receives from the eNB is shown in FIG. 5 It is assumed that it has the same form as shown in .

Therefore, when the near UE, that is, the UE#2 (332) signal is received as shown in FIG. 5, interference cancellation (IC, (hereinafter referred to as "IC") operation is performed (step 610). Here, the IC operation for the far UE signal will be described in detail as follows.

First, when the signal is received as shown in FIG. 5, the UE#2 (332) detects and decodes the signal corresponding to reference number 511 among the UE#1 signals, that is, the target signal #1 (step 611). , the target signal #1 is removed from the received signal (step 612). Then, the UE #2 (332) detects and decodes a signal corresponding to reference number 513, that is, target signal #2, among the received signals (step 613), and detects and decodes the target signal #1 and the target signal from the received signal. Remove #2 (step 614).

When the IC operation for the far UE is completed in this way, the UE#2 332 calculates a log likelihood ratio (LLR) for the near UE signal, that is, the UE#2 signal. ) is calculated (step 620).

Then, the UE#2 332 performs a turbo decoding operation on the UE#2 signal (step 630).

In Figure 6, the operation process of near UE in a wireless communication system supporting the power domain NOMA-SWSC method according to an embodiment of the present invention is explained. Next, with reference to Figure 7, the power domain according to an embodiment of the present invention. The operation process of far UE in a wireless communication system supporting the domain NOMA-SWSC method will be described.

Figure 7 is a diagram schematically showing the operation process of a far UE in a wireless communication system supporting the power domain NOMA-SWSC method according to an embodiment of the present invention.

Referring to FIG. 7, first, the far UE determines whether the power domain NOMA method is applied to the UE paired with the far UE in the SWSC encoding method when the SWSC encoding method is applied from the transmitting device, for example, the eNB to the far UE. If the power domain NOMA method is applied to the UE that is paired with the far UE, information about the applied NOMA method is received.

In addition, the operation process of the far UE shown in FIG. 7 is the operation process of the UE existing in the same environment as UE #1 (331) shown in FIG. 3, and the signal that the far UE receives from the eNB is shown in FIG. 5 It is assumed that it has the same form as shown in .

Therefore, when the far UE, that is, the UE#1 331, receives a signal as shown in FIG. 5, the far UE signal, that is, the signal corresponding to reference number 511 among the UE#1 signals, that is, the target signal # 1 is detected and decoded (step 710), and the target signal #1 is removed from the received signal (step 720). Then, the UE #1 (331) detects and decodes the signal corresponding to reference number 515, that is, DI signal #1, among the received signals (step 730), and detects and decodes the target signal #1 and DI signal # from the received signal. Remove 1 (step 740). Here, the operation of detecting and decoding the target signal #1 is as follows.

First, the UE#1 331 calculates the LLR for the UE#1 signal (step 711) and performs a turbo decoding operation on the UE#1 signal (step 712).

Second, the SCMA-SWSC method in the wireless communication system according to an embodiment of the present invention will be described.

Figure 8 is a diagram schematically showing signal transmission/reception operations according to the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 8, the wireless communication system includes a plurality of eNBs, for example, two eNBs, for example, eNB #1 (810) and eNB #2 (820), and a plurality of UEs, for example, four UEs, for example, include UE#1 (831), UE#2 (832), UE#3 (833), and UE#4 (834). Here, it is assumed that the reference UE is the UE#1 (831), and therefore, the eNB#1 (810) becomes the serving eNB for the UE#1 (831), and the eNB#2 (820) becomes an interfering eNB that transmits an interference signal to the UE #1 (831).

In addition, UE#1 (831) and UE#2 (832) are SCMA paired UEs paired based on the SCMA method, and UE#1 (831) and UE#3 (833) are paired based on the SWSC method. These are SWSC paired UEs. Additionally, UE#3 (833) and UE#4 (834) are SCMA paired UEs that are also paired based on the SCMA method. That is, in FIG. 8, UE#1 (831) and UE#2 (832) form a SCMA pair, UE#1 (831) and UE#3 (833) form a SWSC pair, and UE#3 ( 833) and UE#4 (834) form a SCMA pair.

In order to support the SCMA-SWSC method according to an embodiment of the present invention, the structure and operation process of each transmitting device, such as an eNB and a receiving device, such as UE, must be changed, which will be described in detail as follows.

First, the structure and operation process of a transmission device supporting the SCMA-SWSC method according to an embodiment of the present invention will be described as follows.

First, a transmitting device, for example an eNB, must reflect the SWSC encoder output characteristics in the general SCMA method. That is, the UE#1 signal to which the SWSC encoding method is applied must be included in the SCMA codebook. Therefore, in one embodiment of the present invention, it is necessary to change the structure of UE #1 in consideration of the conditions described above.

In addition, in one embodiment of the present invention, the detection performance of UE #1 to which the SCMA codebook is applied needs to be considered when pairing SWSC UE, and the SCMA codebook is applied to UE #3, which is an interfering UE for UE #1. can be considered.

Next, the receiving device, for example, the UE, must reflect the SWSC decoding operation in the general SCMA operation. That is, a UE supporting the SCMA-SWSC method, which is a combination of the SWSC method and the SCMA method, must apply the SCMA decoding operation when performing the SWSC decoding operation.

Therefore, in the SCMA-SWSC method according to an embodiment of the present invention, the eNB must provide the following information to the UE. In other words, the information provided to far UE is as follows.

(1) When the SWSC method is applied to the far UE, information indicating whether the SCMA method is applied to the UE paired with the far UE in the SWSC method.

In Figure 8, the far UE is UE#1 (831), and the UE paired with UE#1 (831) in the SWSC method is UE#3 (833). That is, the UE#1 (831) and UE#3 (833) form a SWSC pair.

(2) When the SCMA method is applied to UE#3 (833), information about the UE that constitutes the SCMA pair with UE#3 (833), that is, UE#4 (834)

Here, the information about the UE#4 (834) includes MCS level, scrambling sequence, resource allocation information, and SCMA codebook applied to the UE#3 (833) and UE#4 (834). may include.

Then, with reference to FIG. 9, the internal structure of a transmission device supporting the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention will be described.

Figure 9 is a diagram schematically showing the internal structure of a transmission device supporting the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 9, a transmitting device, for example, an eNB, includes a SWSC encoder 910, an adder 920, a turbo encoder 930, a modulator 940, and a symbol generator 950. Here, the modulator 940 is based on SCMA codebook-based modulation.

In addition, the SWSC encoder 910 includes a plurality of short turbo encoders, such as short turbo encoder #1 (911-1), short turbo encoder #2 (911-2), a delay unit 913, and a modulator. It includes (915) and a symbol generator (917). Here, the modulator 915 performs a modulation operation based on the SCMA codebook-based modulation method.

In Figure 9, parameter b represents a parameter used in the SCMA method, and a detailed description of the parameter b will be omitted.

A signal to be transmitted to a far UE, for example, UE#1, is input to the SWSC encoder 910, and thus the signal is input to the plurality of short turbo encoders, and the plurality of short turbo encoders each transmit the signal. Encode according to the short turbo encoding method. As an example, the short turbo encoder #1 (911-1) outputs the encoded signal to the modulator 915, and the short turbo encoder #2 (911-2) outputs the encoded signal to the delay unit ( 913). The delay unit 415 delays the signal output from the short turbo encoder #2 (911-2) by a preset time and then outputs it to the modulator 915.

The modulator 915 modulates the signal output from the short turbo encoder #1 (911-1) and the signal output from the delay unit 913 based on the SCMA codebook-based modulation method, and then the symbol generator 917 ) is output. The symbol generator 917 generates a symbol for UE #1, that is, an SCMA symbol, and outputs it to the adder 920.

Meanwhile, a signal to be transmitted to a near UE, for example, UE#2, is input to the turbo encoder 930, and the turbo encoder 930 encodes the signal corresponding to the turbo encoding method and converts the encoded signal into It is output to the modulator 940. The modulator 940 modulates the signal output from the turbo encoder 930 according to the SCMA codebook-based modulation method and outputs the modulated signal to the symbol generator 950. The symbol generator 950 generates a symbol for UE #2, that is, an SCMA symbol, and outputs it to the adder 920.

The adder 920 adds the signal output from the symbol generator 917 and the signal output from the symbol generator 950 based on the parameter b to generate a serving eNB signal, and the serving eNB signal is transmitted to UEs. , that is, it is transmitted to UE#1 and UE#2.

Meanwhile, Figure 9 shows a case where the SWSC encoder 910, adder 920, turbo encoder 930, modulator 940, and symbol generator 950 are implemented as separate units. Of course, at least two of the SWSC encoder 910, adder 920, turbo encoder 930, modulator 940, and symbol generator 950 can be integrated. In addition, of course, the SWSC encoder 910, the adder 920, the turbo encoder 930, the modulator 940, and the symbol generator 950 may be implemented with one processor.

In FIG. 9, the internal structure of a transmitting device supporting the SCMA-SWSC method in a wireless communication system according to an embodiment of the present invention is explained. Next, referring to FIG. 10, the SCMA-SWSC method according to an embodiment of the present invention is explained. An example of the operation process of a receiving device in a wireless communication system supporting the method will be described.

Figure 10 is a diagram schematically showing an example of an operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method according to an embodiment of the present invention.

Referring to FIG. 10, it should be noted that the operation process of the receiving device shown in FIG. 10 is the operation process of a UE existing in the same environment as UE #1 (831) shown in FIG. 8.

First, when a transmitting device, for example, an eNB, transmits based on the SCMA-SWSC method, UE#1 receives the UE#1 signal, which is a signal targeting UE#1, and UE# forming a NOMA pair with the UE#1. The UE#2 signal, which is a signal targeting 2, and the UE#3 signal, which is a signal targeting UE#3, which forms a SWSC pair with UE#1, are received together. Here, the UE#3 signal becomes a DI signal for the UE#1. In addition, since the SWSC method is applied to the UE#1 signal and the UE#3 signal, the UE#1 signal and the UE#3 signal overlap a number of signals based on a parameter used in the SWSC method, for example, a weight coefficient. Able to know.

Therefore, the UE#1 performs a decoding operation corresponding to the SCMA method for the UE#1 signal and the UE#2 signal, and performs a decoding operation corresponding to the SWSC method for the UE#1 signal and the UE#3 signal. Perform. And, the UE#1 performs a decoding operation corresponding to the SCMA method on the UE#3 signal and the UE#4 signal.

In Figure 10, an example of the operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method according to an embodiment of the present invention is explained. Next, with reference to Figure 11, according to an embodiment of the present invention. Another example of the operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method will be described.

Figure 11 is a diagram schematically showing another example of the operation process of a receiving device in a wireless communication system supporting the SCMA-SWSC method according to an embodiment of the present invention.

Referring to FIG. 11, first, UEs, such as UE#1 and UE#2, receive information necessary to support the SCMA-SWSC method from a transmitting device, such as an eNB. As an example, when the far UE, i.e. UE#1, applies the SWSC method to UE#1, information indicating whether the SCMA method is applied to the UE paired with UE#1 in the SWSC method, i.e., UE#3, and When the SCMA method is applied to UE#3, information about the UE that forms a SCMA pair with UE#3, that is, UE#4, is received.

Additionally, it is assumed that the signal that UE #1 receives from the eNB has the same similar form as shown in FIG. 10.

Therefore, when a signal is received, UE #1 detects and decodes the signal corresponding to reference number 1011, that is, target signal #1 among the UE #1 signals (step 1110), and removes the target signal #1 from the received signal. Do this (step 1120). Then, the UE #1 detects and decodes the signal corresponding to reference number 1015 and target signal #2 among the received signals (step 1130), and corresponds to the target signal #1 and target signal #2 in the received signal. Remove the signal (step 1140).

Here, the operations of steps 1110 and 1130 are as follows.

First, the UE#1 calculates the LLR for the UE#1 signal and the UE#2 signal (step 1111). Then, the UE#1 performs a turbo decoding operation on the UE#1 signal (step 1112-1) and performs a turbo decoding operation on the UE#2 signal (step 1112-2). Here, the LLR calculation operation is based on a message passing algorithm.

Additionally, the UE#1 calculates the LLR for the UE#3 signal and the UE#4 signal (step 1131). Then, the UE#1 performs a turbo decoding operation on the UE#3 signal (step 1132-1) and performs a turbo decoding operation on the UE#4 signal (step 1132-2). Here, the LLR calculation operation is based on a message passing algorithm.

Third, the IDMA-SWSC method in the wireless communication system according to an embodiment of the present invention will be described.

Figure 12 is a diagram schematically showing signal transmission/reception operations according to the IDMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 12, the wireless communication system includes a plurality of eNBs, for example, two eNBs, for example, eNB #1 (1210) and eNB #2 (1220), and a plurality of UEs, for example, four UEs, for example, include UE#1 (1231), UE#2 (1232), UE#3 (1233), and UE#4 (1234). Here, it is assumed that the reference UE is the UE#1 (1231), and therefore the eNB#1 (1210) becomes the serving eNB for the UE#1 (1231), and the eNB#2 (1220) becomes an interfering eNB that transmits an interference signal to the UE #1 (1231).

In addition, UE#1 (1231) and UE#2 (1232) are IDMA paired UEs paired based on the IDMA method, and UE#1 (1231) and UE#3 (1233) are paired based on the SWSC method. These are SWSC paired UEs. Additionally, UE#3 (1233) and UE#4 (1234) are IDMA paired UEs that are also paired based on the IDMA method. That is, the UE#1 (1231) and UE#2 (1232) form an IDMA pair, the UE#1 (1231) and UE#3 (1233) form a SWSC pair, and the UE#3 (1233) ) and UE#4 (1234) form an IDMA pair.

In order to support the IDMA-SWSC method according to an embodiment of the present invention, the structure and operation process of each transmitting device, such as an eNB and a receiving device, such as UE, must be changed, which will be described in detail as follows.

First, the structure and operation process of a transmission device supporting the IDMA-SWSC method according to an embodiment of the present invention will be described as follows.

First, a transmitting device, for example an eNB, must reflect the SWSC encoder output characteristics in the general IDMA method. That is, repetition and user-specific interleaving processes must be added to the SWSC encoding process, and applying different interleaving methods in the short turbo encoding process used in the SWSC encoding process can be considered. .

Therefore, in one embodiment of the present invention, it is necessary to change the structure of UE #1 in consideration of the conditions described above.

Next, the receiving device, for example, the UE, must reflect the SWSC decoding operation in the general IDMA decoding operation. That is, a UE that supports the IDMA-SWSC method, which is a combination of the SWSC method and the IDMA method, must apply the SWSC decoding operation when performing the IDMA decoding operation.

Therefore, in the IDMA-SWSC method according to an embodiment of the present invention, the eNB must provide the following information to the UE.

(1) Information indicating whether the IDMA method is applied to UE#3, which constitutes UE#1 and SWSC pair

(2) If the IDMA method is applied to UE#3, information about UE#4 that forms an IDMA pair with UE#3

Here, the information about UE#4 includes the MCS level, scrambling sequence, resource allocation information, and information about the IDMA method applied to UE#3 and UE#4, for example, the number of repetitions and the interleaving pattern. ), etc. may be included.

Then, with reference to FIG. 13, the internal structure of a transmission device supporting the IDMA-SWSC method in a wireless communication system according to an embodiment of the present invention will be described.

Figure 13 is a diagram schematically showing the internal structure of a transmission device supporting the IDMA-SWSC method in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 13, first, a transmitting device, for example, an eNB, includes a SWSC encoder 1310, an adder 1320, a turbo encoder 1330, a modulator 1340, and a symbol generator 1350. Here, the modulator 1340 is based on the IDMA method.

In addition, the SWSC encoder 1310 includes a plurality of short turbo encoders, such as short turbo encoder #1 (1311-1), short turbo encoder #2 (1311-2), and a plurality of modulators, such as a modulator. #1 (1313-1), modulator #2 (1313-2), etc., a number of adders, for example, adder #1 (1315-1), adder #2 (1315-2), etc., and a symbol generator (1317) ) includes. The plurality of modulators perform modulation operations based on the IDMA method.

In FIG. 13, parameter a represents a parameter used in the SWSC method, for example, a weight coefficient, and parameter b represents a parameter used in the IDMA method, and detailed descriptions of parameter a and parameter b will be omitted.

A signal to be transmitted to a far UE, for example, UE#1, is input to the SWSC encoder 1310, and thus the signal is input to the plurality of short turbo encoders, and the plurality of short turbo encoders each transmit the signal. It is encoded according to the short turbo encoding method, and the encoded signal is output to each of the plurality of modulators.

Each of the plurality of modulators modulates the signal output from the corresponding short turbo encoder according to the IDMA method. Then, the modulator #1 (1313-1) outputs the modulated signal to the adder #1 (1315-1), and the modulator #2 (1313-2) outputs the modulated signal to the adder #2. Output as (1315-2). Here, the internal structure and operation of each of the plurality of modulators, for example, modulator #1 (1313-1) and modulator #2 (1313-2), are similar to the internal structure and operation of the modulator (1340), which will be described below. , Therefore, the detailed description will be omitted here.

The plurality of adders each perform an addition operation corresponding to parameter a and then output the added signal to the symbol generator 1317. The symbol generator 1317 generates a symbol for UE #1, that is, an IDMA symbol, and outputs it to the adder 1320.

Meanwhile, a signal to be transmitted to a near UE, for example, UE#2, is input to the turbo encoder 1330, and the turbo encoder 1330 encodes the signal corresponding to the turbo encoding method and converts the encoded signal into It is output to the modulator 1340. The modulator 1340 modulates the signal output from the turbo encoder 1330 according to the IDMA method and outputs the modulated signal to the symbol generator 1350. The symbol generator 1350 generates a symbol for UE #2, that is, an IDMA symbol, and outputs it to the adder 1320.

The adder 1320 adds the signal output from the symbol generator 1317 and the signal output from the symbol generator 1350 based on parameter b to generate a serving eNB signal, and the serving eNB signal is transmitted to UEs, That is, it is transmitted to UE#1 and UE#2.

Meanwhile, Figure 13 shows a case where the SWSC encoder 1310, adder 1320, turbo encoder 1330, modulator 1340, and symbol generator 1350 are implemented as separate units. Of course, at least two of the SWSC encoder 1310, adder 1320, turbo encoder 1330, modulator 1340, and symbol generator 1350 can be integrated. In addition, of course, the SWSC SWSC encoder 1310, the adder 1320, the turbo encoder 1330, the modulator 1340, and the symbol generator 1350 may be implemented with one processor.

Meanwhile, the operation process of the receiving device supporting the IDMA method in the wireless communication system according to an embodiment of the present invention is similar to the operating process of the receiving device as described in FIG. 5. That is, when a transmitting device, for example, an eNB, transmits a signal based on the IDMA method, UE#1 receives the UE#1 signal, which is a signal targeting UE#1, and UE# forming a NOMA pair with the UE#1. The UE#2 signal, which is a signal targeting 2, and the UE#3 signal, which is a signal targeting UE#3, which forms a SWSC pair with UE#1, are received together. Here, the UE#3 signal becomes a DI signal for the UE#1. Additionally, since the SWSC method is applied to the UE#1 signal and the UE#3 signal, it can be seen that the UE#1 signal and the UE#3 signal overlap a number of signals based on parameter a.

Therefore, the UE#1 performs a decoding operation corresponding to the IDMA method for the UE#1 signal and the UE#2 signal, and performs a decoding operation corresponding to the SWSC method for the UE#1 signal and the UE#3 signal. Perform. Additionally, the UE#1 performs a decoding operation corresponding to the IDMA method on the signal of UE#4, which constitutes the NOMA pair with the UE#3.

In addition, the decoding operation of the UE #1 uses information provided by the eNB, that is, information indicating whether the IDMA method is applied to the UE #3, that is, the UE paired with the UE #1 in the SWSC method, and the UE When the IDMA method is applied to #3, information about UE #4, i.e., the UE constituting the IDMA pair with UE #3, i.e., MCS level applied to UE #4, scrambling sequence and resource allocation information, etc. It is performed based on information about the IDMA method applied to UE#3 and UE#4, that is, the number of repetitions, interleaving pattern, etc.

Next, with reference to FIG. 14, the operation process of the signal receiving device in a wireless communication system supporting the IDMA-SWSC method according to an embodiment of the present invention will be described.

Figure 14 is a diagram schematically showing the operation process of a signal reception device in a wireless communication system supporting the IDMA-SWSC method according to an embodiment of the present invention.

Referring to FIG. 14, first, the IDMA method is applied to the signal receiving device, for example, far UE, i.e., UE#1, and the UE, i.e., UE#3, which forms a SWSC pair with the far UE from the transmitting device, e.g., eNB#1. When the IDMA method is applied to UE#3, information about UE#4, a UE forming an IDMA pair, is received from the UE#3 and the interfering eNB, i.e., eNB#2.

In addition, the operation process of the far UE shown in FIG. 14 is the operation process of the UE existing in the same environment as UE #1 (1231) shown in FIG. 12, and the signal that the far UE receives from the eNB is shown in FIG. 5 It is assumed that it has the same form as shown in .

Therefore, when the far UE, that is, the UE #1 (1231), receives a signal as shown in FIG. 5, the signal is received through an elementary signal estimator (ESE, hereinafter referred to as “ESE”). An estimation operation is performed on the received signal (step 1410), and a user-specific deinterleaving operation is performed on the estimated signal (step 1420). step). Then, the UE#1 (1231) decodes the user-specific deinterleaved signal using a turbo decoding method and outputs the turbo decoded signal (step 1430). The turbo decoded signal is input to the ESE.

Meanwhile, the UE #1 (1231) performs a user-specific deinterleaving operation on the estimated signal, that is, a user-specific deinterleaving operation corresponding to the interleaving pattern for UE #1 (1231) (step 1440). Then, the UE#1 (1231) decodes the user-specific deinterleaved signal using the SWSC-based turbo decoding method and outputs the SWSC-based turbo decoded signal (step 1450). The SWSC-based turbo decoded signal is input to the ESE.

Here, the SWSC-based turbo decoding method will be described in detail as follows.

First, when the signal is received as shown in FIG. 5, the UE #1 (1231) detects and decodes the far UE signal, that is, the signal corresponding to reference number 511 among the UE #1 signals, that is, the target signal #1. (step 1451), and the target signal #1 is removed from the received signal (step 1453). Then, the UE #1 (331) detects and decodes the signal corresponding to reference number 515, that is, DI signal #1, among the received signals (step 1455), and detects and decodes the target signal #1 and the DI signal from the received signal. Remove #1 (step 1457).

Certain aspects of the invention may also be implemented as computer readable code on a computer readable recording medium. A computer-readable recording medium is any data storage device capable of storing data that can be read by a computer system. Examples of the computer-readable recording media include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, and , floppy disks, optical data storage devices, and carrier waves (such as data transmission over the Internet). The computer-readable recording medium may also be distributed across networked computer systems, such that the computer-readable code is stored and executed in a distributed manner. Additionally, functional programs, codes, and code segments for accomplishing the present invention can be easily interpreted by programmers skilled in the field to which the present invention is applied.

It will also be appreciated that the device and method according to an embodiment of the present invention can be implemented in the form of hardware, software, or a combination of hardware and software. Any such software may, for example, store on volatile or non-volatile storage devices such as ROM, whether erasable or rewritable, or on memory such as RAM, memory chips, devices or integrated circuits. , or, for example, may be stored in a storage medium that is optically or magnetically recordable and readable by a machine (e.g., a computer), such as a CD, DVD, magnetic disk, or magnetic tape. The method according to an embodiment of the present invention may be implemented by a computer or a portable terminal including a control unit and a memory, and the memory is suitable for storing a program or programs containing instructions for implementing the embodiments of the present invention. You can see that it is an example of a machine-readable storage medium.

Accordingly, the present invention includes a program containing code for implementing the device or method described in any claim of the present specification and a machine-readable storage medium (such as a computer) storing such a program. Additionally, such programs may be transmitted electronically through any medium, such as communication signals transmitted over a wired or wireless connection, and the present invention includes equivalents thereof as appropriate.

Additionally, the device according to an embodiment of the present invention can receive and store the program from a program providing device that is connected wired or wirelessly. The program providing device includes a memory for storing a program containing instructions for causing the program processing device to perform a preset content protection method, information necessary for the content protection method, etc., and wired or wireless communication with the graphics processing device. It may include a communication unit for executing the program, and a control unit for automatically transmitting the program to the transmitting and receiving device at the request of the graphics processing device.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but of course, various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the patent claims described later, but also by the scope of this patent claim and equivalents.

Claims (20)

In a method of operating a transmitting device in a wireless communication system,
When the sliding window superposition coding (SWSC) method is applied to the first receiving device, non-orthogonal multiple access (NOMA) is applied to the second receiving device paired with the first receiving device. ) and transmitting first information indicating whether the method is applied and second information, which is information related to the NOMA method, to the first receiving device when the NOMA method is applied to the second receiving device. A method of operating a transmitting device in a characterized wireless communication system.
According to paragraph 1,
Wireless communication further comprising transmitting third information indicating whether the SWSC method is applied to the first receiving device and fourth information, which is information related to the SWSC method, to the third receiving device. How the transmitting device operates in the system.
According to paragraph 2,
A method of operating a transmitting device in a wireless communication system, wherein the NOMA method is a power domain NOMA method.
According to paragraph 2,
A method of operating a transmitting device in a wireless communication system, characterized in that the third receiving device is paired with the first receiving device based on the NOMA method in a service area where the transmitting device provides a service.
According to paragraph 2,
The fourth information includes a sliding window overlap application length used in the SWSC method and a weight factor.
According to paragraph 1,
A method of operating a transmitting device in a wireless communication system, characterized in that the second receiving device is paired with the first receiving device based on the NOMA method in a service area where a transmitting device other than the transmitting device provides a service.
According to paragraph 1,
A method of operating a transmitting device in a wireless communication system, wherein the NOMA method is a power domain NOMA method.
In a method of operating a receiving device in a wireless communication system,
From a transmitting device, non-orthogonal multiple access to a first receiving device paired with the receiving device when a sliding window superposition coding (SWSC) method is applied to the receiving device. Wireless communication comprising the process of receiving first information indicating whether the NOMA method is applied and second information that is information related to the NOMA method when the NOMA method is applied to the first receiving device. How the receiving device operates in the system.
According to clause 8,
A process of receiving a signal;
Detecting and decoding, among the received signals, a first target signal targeting a second receiving device paired with the receiving device based on the NOMA method in a service area where the transmitting device provides a service;
removing the first target signal from the received signal;
Detecting and decoding a first downlink interference (DI) signal, which is a signal targeting the first receiving device, from the received signal;
A method of operating a receiving device in a wireless communication system, further comprising removing the first target signal and the first DI signal from the received signal.
According to clause 9,
The first target signal is one of a plurality of overlapping signals generated based on parameters used in the SWSC method applied to the receiving device,
A method of operating a receiving device in a wireless communication system, wherein the first DI signal is one of a plurality of overlapping signals generated based on parameters used in the SWSC method applied to the first receiving device.
According to clause 10,
The process of detecting and decoding the first target signal is:
calculating a log likelihood ratio (LLR) for the first target signal;
A method of operating a receiving device in a wireless communication system, comprising performing a turbo decoding operation on the first target signal.
According to clause 8,
A method of operating a receiving device in a wireless communication system, wherein the NOMA method is a power domain NOMA method.
According to clause 8,
A method of operating a transmitting device in a wireless communication system, characterized in that the first receiving device is paired with the first receiving device based on the NOMA method in a service area where a transmitting device other than the transmitting device provides a service.
In a method of operating a receiving device in a wireless communication system,
From the transmitting device, the sliding window superposition coding (SWSC) method is applied to the first receiving device that is paired with the receiving device based on a non-orthogonal multiple access (NOMA) method. A method of operating a receiving device in a wireless communication system, comprising the step of receiving first information indicating whether to use the SWSC method and second information related to the SWSC method.
According to clause 14,
A method of operating a receiving device in a wireless communication system, wherein the NOMA method is a power domain NOMA method.
According to clause 14,
A method of operating a receiving device in a wireless communication system, wherein the second information includes a sliding window overlap application length used in the SWSC method and a weight factor.
According to clause 14,
A process of receiving a signal;
performing an interference cancellation (IC) operation on a signal targeting the first receiving device among the received signals;
calculating a log likelihood ratio (LLR) for a signal from which interference signals have been removed among the received signals;
A method of operating a receiving device in a wireless communication system, further comprising performing a turbo decoding operation on a signal from which an interference signal has been removed among the received signals.
According to clause 17,
The process of performing an IC operation on a signal targeting the first receiving device among the received signals is:
detecting and decoding a first target signal targeting the receiving device;
removing the first target signal from the received signal;
detecting and decoding a second target signal targeting the receiving device;
A method of operating a receiving device in a wireless communication system, comprising removing the first target signal and the second target signal from the received signal.
According to clause 18,
A method of operating a receiving device in a wireless communication system, wherein each of the first target signal and the second target signal is one of a plurality of overlapping signals generated based on parameters used in the SWSC method applied to the receiving device. .
According to clause 19,
A method of operating a receiving device in a wireless communication system, wherein the NOMA method is a power domain NOMA method.

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