WO2016200066A1 - Method and device for selecting multiple users and allocating resources for non-orthogonal multiple access in wireless communication system - Google Patents

Abstract

The present application provides a method for allocating resources in a wireless communication system using multiple antennas. Here, the method for allocating resources may comprise the steps of: transmitting a reference signal to first-type terminals on the basis of type information of a plurality of terminals; receiving channel estimation information from the first-type terminals that have received the reference signal; generating beams on the basis of the received channel estimation information; and allocating resources for the generated beams. Here, if the resources for the beams are allocated, first-type beams for the first-type terminals are primarily generated and allocated, and on the basis of the generated first-type beams, second-type beams for second-type terminals may be non-orthogonally generated and allocated.

Description

Method and apparatus for multi-user selection and resource allocation for non-orthogonal multiple access in wireless communication system

The present invention relates to a wireless communication system, and to a method for transmitting and receiving a signal and a resource allocation method based on a non-orthogonal multiple access (NOMA) in a base station having multiple antennas.

As an example of a wireless communication system to which the present invention can be applied, a 3GPP LTE (3rd Generation Partnership Project Long Term Evolution (LTE)) communication system will be described.

1 is a diagram schematically illustrating an E-UMTS network structure as an example of a wireless communication system. The Evolved Universal Mobile Telecommunications System (E-UMTS) system is an evolution from the existing Universal Mobile Telecommunications System (UMTS), and is currently undergoing basic standardization in 3GPP. In general, the E-UMTS may be referred to as a Long Term Evolution (LTE) system. For details of the technical specification of the UMTS and the E-UMTS, refer to "3rd Generation Partnership Project; Technical Specification Group Radio Access Network", respectively.

Referring to FIG. 1, an E-UMTS is an access gateway (AG) located at an end of a user equipment (UE) and a base station (eNode B), an eNB, and a network (E-UTRAN) and connected to an external network. The base station may transmit multiple data streams simultaneously for broadcast service, multicast service and / or unicast service.

One or more cells exist in one base station. The cell is set to one of bandwidths such as 1.25, 2.5, 5, 10, 15, and 20Mhz to provide downlink or uplink transmission services to multiple terminals. Different cells may be configured to provide different bandwidths. The base station controls data transmission and reception for a plurality of terminals. For downlink (DL) data, the base station transmits downlink scheduling information to inform the corresponding UE of time / frequency domain, encoding, data size, and HARQ (Hybrid Automatic Repeat and reQuest) related information. In addition, the base station transmits uplink scheduling information to the terminal for uplink (UL) data and informs the time / frequency domain, encoding, data size, HARQ related information, etc. that the terminal can use. An interface for transmitting user traffic or control traffic may be used between base stations. The core network (CN) may be composed of an AG and a network node for user registration of the terminal. The AG manages the mobility of the UE in units of a tracking area (TA) composed of a plurality of cells.

Wireless communication technology has been developed to LTE based on WCDMA, but the demands and expectations of users and operators are continuously increasing.

An object of the present specification is to provide a method and apparatus for transmitting and receiving a signal based on a NOMA in a base station having multiple antennas in a wireless communication system.

An object of the present specification is to provide a method and apparatus for allocating resources based on a NOMA in a base station having multiple antennas in a wireless communication system.

An object of the present specification is to provide a method and apparatus for transmitting and receiving a signal based on closed-loop multi-input multi-output (MIMO) and open-loop MIMO in a wireless communication system.

An object of the present specification is to provide a method and apparatus for transmitting and receiving a signal based on a type of a terminal in a wireless communication system.

According to one embodiment of the present specification, a method of allocating resources in a wireless communication system using multiple antennas may be included. In this case, the method for allocating resources may include transmitting a reference signal to first type terminals based on the type information of the plurality of terminals, and obtaining channel estimation information from the first type terminals receiving the reference signal. Receiving, generating beams based on the received channel estimation information, and allocating resources for the generated beams. In this case, when resources for beams are allocated, first type beams for first type terminals are first generated and allocated, and second type beams for the second type terminal are non-based based on the generated first type beams. Can be created and assigned non-orthogonal.

In addition, according to an embodiment of the present disclosure, it may include a base station for allocating resources in a wireless communication system using multiple antennas. In this case, the base station may include a receiving module for receiving the information from the external device, a transmitting module for transmitting the information from the external device, and a processor for controlling the receiving module and the transmitting module. In this case, the processor transmits a reference signal to the first type terminals based on the type information of the plurality of terminals using the transmission module, and the first type terminals that receive the reference signal using the reception module. Receiving channel estimation information from the base station, generating beams based on the received channel estimation information, and allocating resources for the generated beams, wherein resources for the beams are allocated. First type beams may be generated and allocated first, and second type beams for the second type terminal may be generated and assigned non-orthogonal based on the generated first type beams.

In addition, the following may be commonly applied to a method of allocating resources and a base station apparatus in a wireless communication system.

According to an embodiment of the present invention, the first type beams and the second type beams may be allocated together non-orthogonally in one resource region. In this case, one resource region may be divided into a first space including Nc first type beams and a second space including No second type beams based on multiple antennas.

In this case, according to an embodiment of the present invention, the second space may be generated based on the generated first space after the first space is generated.

In addition, according to an embodiment of the present invention, the second space may be divided based on a beam codebook.

In addition, according to an embodiment of the present invention, No second type beams included in the second space may be transmitted based on a hopping pattern.

In addition, according to an embodiment of the present invention, the No second type beams included in the second space may be transmitted based on a spreading pattern.

In addition, according to an embodiment of the present invention, the first type beam may be a closed-loop beam, and the second type beam may be an open-loop beam.

In addition, according to an embodiment of the present invention, the first type terminal may be a human type terminal, and the second type terminal may be a machine type terminal.

In addition, according to an embodiment of the present invention, it is possible to receive type information about each terminal from a plurality of terminals. In this case, the type information about the terminal may be included in the physical uplink shared channel (PUSCH) and received.

The present disclosure may provide a method and apparatus for transmitting and receiving a signal based on a NOMA in a base station having multiple antennas in a wireless communication system.

The present disclosure can provide a method and apparatus for allocating resources based on a NOMA in a base station having multiple antennas in a wireless communication system.

The present disclosure can provide a method and apparatus for transmitting and receiving a signal based on closed-loop multi input multi output (MIMO) and open-loop MIMO in a wireless communication system.

The present disclosure may provide a method and apparatus for transmitting and receiving a signal based on a type of a terminal in a wireless communication system.

Effects obtained in the present specification are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 is a diagram schematically illustrating an E-UMTS network structure as an example of a wireless communication system.

2 is a diagram for explaining the structure of a radio frame.

3 is a diagram illustrating a resource grid in a downlink slot.

4 is a diagram illustrating a structure of a downlink subframe.

5 is a diagram illustrating a structure of an uplink subframe.

6 is a configuration diagram of a wireless communication system having multiple antennas.

7 is a diagram illustrating a method for allocating resources by the NOMA method.

8 is a diagram illustrating a method of generating beams according to a type in a terminal.

9 is a diagram illustrating a terminal divided into two types.

FIG. 10 is a diagram illustrating a resource block (RB) according to two types.

11 is a diagram illustrating an open-loop beam codebook.

12 is a diagram illustrating an open-loop beam selection method.

13 is a diagram illustrating an example of an open-loop beam selection scheme.

14 is a flowchart illustrating a flow chart according to an embodiment of the present specification.

15 is a flowchart illustrating a flow chart according to an embodiment of the present specification.

16 is a block diagram of a base station apparatus and a terminal apparatus according to an embodiment of the present specification.

The following embodiments combine the components and features of the present invention in a predetermined form. Each component or feature may be considered to be optional unless otherwise stated. Each component or feature may be embodied in a form that is not combined with other components or features. In addition, some components and / or features may be combined to form an embodiment of the present invention. The order of the operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.

In the present specification, embodiments of the present invention will be described based on a relationship between data transmission and reception between a base station and a terminal. Here, the base station has a meaning as a terminal node of the network that directly communicates with the terminal. The specific operation described as performed by the base station in this document may be performed by an upper node of the base station in some cases.

That is, it is obvious that various operations performed for communication with a terminal in a network composed of a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. A 'base station (BS)' may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point (AP), and the like. The repeater may be replaced by terms such as relay node (RN) and relay station (RS). In addition, the term “terminal” may be replaced with terms such as a user equipment (UE), a mobile station (MS), a mobile subscriber station (MSS), a subscriber station (SS), and the like.

Specific terms used in the following description are provided to help the understanding of the present invention, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present invention.

In some instances, well-known structures and devices may be omitted or shown in block diagram form centering on the core functions of the structures and devices in order to avoid obscuring the concepts of the present invention. In addition, the same components will be described with the same reference numerals throughout the present specification.

Embodiments of the present invention may be supported by standard documents disclosed in at least one of the wireless access systems IEEE 802 system, 3GPP system, 3GPP LTE and LTE-Advanced (LTE-A) system and 3GPP2 system. That is, steps or parts which are not described to clearly reveal the technical spirit of the present invention among the embodiments of the present invention may be supported by the above documents. In addition, all terms disclosed in the present document can be described by the above standard document.

The following techniques include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and the like. It can be used in various radio access systems. CDMA may be implemented with a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be implemented with wireless technologies such as Global System for Mobile communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE). OFDMA may be implemented in a wireless technology such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) long term evolution (LTE) is part of an Evolved UMTS (E-UMTS) using E-UTRA, and employs OFDMA in downlink and SC-FDMA in uplink. LTE-A (Advanced) is the evolution of 3GPP LTE. WiMAX can be described by the IEEE 802.16e standard (WirelessMAN-OFDMA Reference System) and the advanced IEEE 802.16m standard (WirelessMAN-OFDMA Advanced system). For clarity, the following description focuses on 3GPP LTE and 3GPP LTE-A systems, but the technical spirit of the present invention is not limited thereto.

2 is a diagram for explaining the structure of a radio frame.

In a cellular OFDM wireless packet communication system, uplink / downlink data packet transmission is performed in units of subframes, and one subframe is defined as a predetermined time interval including a plurality of OFDM symbols. The 3GPP LTE standard supports a type 1 radio frame structure applicable to frequency division duplex (FDD) and a type 2 radio frame structure applicable to time division duplex (TDD).

2 (a) is a diagram showing the structure of a type 1 radio frame. The downlink radio frame consists of 10 subframes, and one subframe consists of two slots in the time domain. The time it takes for one subframe to be transmitted is called a transmission time interval (TTI). For example, one subframe may have a length of 1 ms and one slot may have a length of 0.5 ms. One slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. In the 3GPP LTE system, since OFDMA is used in downlink, an OFDM symbol represents one symbol period. An OFDM symbol may also be referred to as an SC-FDMA symbol or symbol period. A resource block (RB) is a resource allocation unit and may include a plurality of consecutive subcarriers in one slot.

The number of OFDM symbols included in one slot may vary depending on the configuration of a cyclic prefix (CP). CP has an extended CP (normal CP) and a normal CP (normal CP). For example, when an OFDM symbol is configured by a general CP, the number of OFDM symbols included in one slot may be seven. When an OFDM symbol is configured by an extended CP, since the length of one OFDM symbol is increased, the number of OFDM symbols included in one slot is smaller than that of the normal CP. In the case of an extended CP, for example, the number of OFDM symbols included in one slot may be six. If the channel state is unstable, such as when the terminal moves at a high speed, an extended CP may be used to further reduce intersymbol interference.

When a general CP is used, since one slot includes 7 OFDM symbols, one subframe includes 14 OFDM symbols. In this case, the first two or three OFDM symbols of each subframe may be allocated to a physical downlink control channel (PDCCH), and the remaining OFDM symbols may be allocated to a physical downlink shared channel (PDSCH).

2 (b) is a diagram illustrating a structure of a type 2 radio frame. Type 2 radio frames consist of two half frames, each of which has five subframes, downlink pilot time slot (DwPTS), guard period (GP), and uplink pilot time slot (UpPTS). One subframe consists of two slots. DwPTS is used for initial cell search, synchronization or channel estimation at the terminal. UpPTS is used for channel estimation at the base station and synchronization of uplink transmission of the terminal. The guard period is a period for removing interference generated in the uplink due to the multipath delay of the downlink signal between the uplink and the downlink. On the other hand, one subframe consists of two slots regardless of the radio frame type.

The structure of the radio frame is only an example, and the number of subframes included in the radio frame or the number of slots included in the subframe and the number of symbols included in the slot may be variously changed.

3 is a diagram illustrating a resource grid in a downlink slot.

One downlink slot includes seven OFDM symbols in the time domain and one resource block (RB) is shown to include 12 subcarriers in the frequency domain, but the present invention is not limited thereto. For example, one slot includes 7 OFDM symbols in the case of a general cyclic prefix (CP), but one slot may include 6 OFDM symbols in the case of an extended-CP (CP). Each element on the resource grid is called a resource element. One resource block includes 12 × 7 resource elements. The number of NDLs of resource blocks included in a downlink slot depends on a downlink transmission bandwidth. The structure of the uplink slot may be the same as the structure of the downlink slot.

4 is a diagram illustrating a structure of a downlink subframe.

Up to three OFDM symbols at the front of the first slot in one subframe correspond to a control region to which a control channel is allocated. The remaining OFDM symbols correspond to data regions to which a physical downlink shared channel (PDSCH) is allocated.

Downlink control channels used in the 3GPP LTE system include, for example, a Physical Control Format Indicator Channel (PCFICH), a Physical Downlink Control Channel (PDCCH), and a Physical HARQ Indicator Channel. Physical Hybrid automatic repeat request Indicator Channel (PHICH). The PCFICH is transmitted in the first OFDM symbol of a subframe and includes information on the number of OFDM symbols used for control channel transmission in the subframe. The PHICH includes a HARQ ACK / NACK signal as a response of uplink transmission. Control information transmitted through the PDCCH is referred to as downlink control information (DCI). DCI includes uplink or downlink scheduling information or an uplink transmit power control command for a certain terminal group. The PDCCH is a resource allocation and transmission format of the downlink shared channel (DL-SCH), resource allocation information of the uplink shared channel (UL-SCH), paging information of the paging channel (PCH), system information on the DL-SCH, on the PDSCH Resource allocation of upper layer control messages such as random access responses transmitted to the network, a set of transmit power control commands for individual terminals in an arbitrary terminal group, transmission power control information, and activation of voice over IP (VoIP) And the like. A plurality of PDCCHs may be transmitted in the control region, and the terminal may monitor the plurality of PDCCHs.

The PDCCH is transmitted in an aggregation of one or more consecutive Control Channel Elements (CCEs). CCE is a logical allocation unit used to provide a PDCCH at a coding rate based on the state of a radio channel. The CCE corresponds to a plurality of resource element groups. The format of the PDCCH and the number of available bits are determined according to the correlation between the number of CCEs and the coding rate provided by the CCEs.

The base station determines the PDCCH format according to the DCI transmitted to the terminal, and adds a cyclic redundancy check (CRC) to the control information. The CRC is masked with an identifier called a Radio Network Temporary Identifier (RNTI) according to the owner or purpose of the PDCCH. If the PDCCH is for a specific terminal, the cell-RNTI (C-RNTI) identifier of the terminal may be masked to the CRC. Or, if the PDCCH is for a paging message, a paging indicator identifier (P-RNTI) may be masked to the CRC. If the PDCCH is for system information (more specifically, system information block (SIB)), the system information identifier and system information RNTI (SI-RNTI) may be masked to the CRC. Random Access-RNTI (RA-RNTI) may be masked to the CRC to indicate a random access response that is a response to the transmission of the random access preamble of the terminal.

5 is a diagram illustrating a structure of an uplink subframe.

The uplink subframe may be divided into a control region and a data region in the frequency domain. A physical uplink control channel (PUCCH) including uplink control information is allocated to the control region. In the data area, a physical uplink shared channel (PUSCH) including user data is allocated. In order to maintain a single carrier characteristic, one UE does not simultaneously transmit a PUCCH and a PUSCH. PUCCH for one UE is allocated to an RB pair in a subframe. Resource blocks belonging to a resource block pair occupy different subcarriers for two slots. This is called a resource block pair allocated to the PUCCH is frequency-hopped at the slot boundary.

Multiple antenna (MIMO) system modelling

6 is a configuration diagram of a wireless communication system having multiple antennas.

As shown in FIG. 6 (a), when the number of transmitting antennas is increased to NT and the number of receiving antennas is increased to NR, theoretical channel transmission is proportional to the number of antennas, unlike when only a plurality of antennas are used in a transmitter or a receiver. Dose is increased. Therefore, the transmission rate can be improved and the frequency efficiency can be significantly improved. As the channel transmission capacity is increased, the transmission rate may theoretically increase as the rate of increase rate Ri multiplied by the maximum transmission rate Ro when using a single antenna.

[Equation 1]

For example, in a MIMO communication system using four transmit antennas and four receive antennas, a transmission rate four times higher than a single antenna system may be theoretically obtained. Since the theoretical capacity increase of multi-antenna systems was proved in the mid 90's, various techniques to actively lead to the actual data rate improvement have been actively studied. In addition, some technologies are already being reflected in various wireless communication standards such as 3G mobile communication and next generation WLAN.

The research trends related to multi-antennas to date include the study of information theory aspects related to the calculation of multi-antenna communication capacity in various channel environments and multi-access environments, the study of wireless channel measurement and model derivation of multi-antenna systems, improvement of transmission reliability, and improvement of transmission rate. Research is being actively conducted from various viewpoints, such as research on space-time signal processing technology.

The communication method in a multi-antenna system will be described in more detail using mathematical modeling. It is assumed that there are NT transmit antennas and NR receive antennas in the system.

Looking at the transmission signal, when there are NT transmit antennas, the maximum information that can be transmitted is NT. The transmission information may be expressed as follows.

[Equation 2]

Each transmission information

The transmit power may be different. Each transmit power

In this case, the transmission information whose transmission power is adjusted may be expressed as follows.

[Equation 3]

Also,

Can be expressed as follows using the diagonal matrix P of the transmission power.

[Equation 4]

Information vector with adjusted transmission power

NT transmission signals that are actually transmitted by applying weight matrix W to

Consider the case where is configured. The weighting matrix W plays a role in properly distributing transmission information to each antenna according to a transmission channel situation.

Can be expressed as follows using the vector X.

[Equation 5]

From here,

Denotes a weight between the i th transmit antenna and the j th information. W is also called a precoding matrix.

Received signal is received signal of each antenna when there are NR receiving antennas

Can be expressed as a vector as

[Equation 6]

In the case of modeling a channel in a multi-antenna wireless communication system, channels may be divided according to transmit / receive antenna indexes. From the transmit antenna j to the channel through the receive antenna i

It is indicated by.

Note that in the order of the index, the receiving antenna index is first, and the index of the transmitting antenna is later.

6 (b) is a diagram illustrating a channel from NT transmit antennas to receive antenna i. The channels may be bundled and displayed in vector and matrix form. In FIG. 6 (b), a channel arriving from a total of NT transmit antennas to a receive antenna i may be represented as follows.

[Equation 7]

Therefore, all channels arriving from NT transmit antennas to NR receive antennas may be expressed as follows.

[Equation 8]

The real channel is added with Additive White Gaussian Noise (AWGN) after passing through the channel matrix H. White noise added to each of NR receive antennas

Can be expressed as

[Equation 9]

The received signal may be expressed as follows through the above-described mathematical modeling.

[Equation 10]

On the other hand, the number of rows and columns of the channel matrix H indicating the channel state is determined by the number of transmit and receive antennas. The number of rows in the channel matrix H is equal to the number NR of receive antennas, and the number of columns is equal to the number NT of transmit antennas. That is, the channel matrix H is NR x NT matrix.

The rank of a matrix is defined as the minimum number of rows or columns that are independent of each other. Thus, the rank of the matrix cannot be greater than the number of rows or columns. The rank (H) of the channel matrix H is limited as follows.

[Equation 11]

Another definition of rank may be defined as the number of nonzero eigenvalues when the matrix is eigenvalue decomposition. Similarly, another definition of rank may be defined as the number of nonzero singular values when singular value decomposition is performed. Thus, rank in the channel matrix. The physical meaning of is the maximum number of different information that can be sent on a given channel.

In the description of this document, 'rank' for MIMO transmission refers to the number of paths that can independently transmit signals at specific time points and specific frequency resources, and 'number of layers' denotes each path. It indicates the number of signal streams transmitted through the system. In general, since the transmitting end transmits the number of layers corresponding to the number of ranks used for signal transmission, unless otherwise specified, the rank has the same meaning as the number of layers.

7 is a diagram illustrating a method for allocating resources by the NOMA method.

As described above, a plurality of multiple antennas may be used in a base station as a method for increasing frequency efficiency in a cellular system. In this case, a technique for increasing the number of antennas used in a base station has been proposed. This method is called Massive MIMO, and transmits a sharp beam to a plurality of users by using spatial freedom of a plurality of multiple antennas, thereby providing high received signal power and low interference power. For example, when the number of transmit antennas is M and the number of users is K, when the channel is independent identically distributed (i.i.d.) Rayleigh fading, the total transmit capacity that can be transmitted may be min {M, K} log2 SNR. That is, the transmission capacity may increase linearly in proportion to the number of min {M, K}.

However, when the number of M and K increases, a complicated transmission / reception scheme may be required to obtain a transmission capacity. For example, when M and K increase, the base station needs to use a dirty-paper coding (DPC) for downlink transmission in order to obtain a transmission capacity. In addition, a joint maximum-likelihood (JML) receiver should be used to receive the transmission link. The computational complexity of these two approaches can increase exponentially with the number of antennas and the number of users. In this case, it may be difficult to use the system due to hardware complexity limitation, delay time limitation, hardware power limitation, etc. based on the computational complexity.

Therefore, there is a need in a real system to use a sub-optimal transmission scheme with low computational complexity. For example, there are orthogonal multiple access and non-orthogonal multiple access (NOMA).

The orthogonal multiple access method allocates independent resources for each user so that interference does not occur between users. Frequency division multiple access divides frequency resources and distributes them to users, and time division multiple times are used for each user. Time division multiple access, and space division multiple access in which space is divided by user. This method has the advantage that the signal modulation and demodulation of the user is simple since it allocates one user per given resource. As described above, orthogonal multiple access schemes are mainly used in LTE and LTE-A.

However, the orthogonal multiple access method has a lower transmission capacity compared to the aforementioned DPC and JML. Therefore, as a scheme for increasing transmission capacity of an orthogonal multiple access scheme, a scheme using both a simple beamforming scheme, zero-forcing beamforming, and user scheduling is used. At this time, the user can theoretically provide performance similar to that of DPC by selecting and transmitting users to prevent performance degradation caused by zero-forcing beamforming compared to DPC. However, even in the aforementioned method, in order to schedule a user, the channel information of the user must be known in advance, and there may be a problem in that resources occupied by an uplink reference signal for obtaining channel information of the user increase. In addition, user scheduling may be effective when the number of users present in the cell is larger than the number of antennas of the base station. However, as described above, in the future communication system to which the Massive MIMO is applied, since there are a plurality of antennas in the base station, the effect on scheduling may be insignificant.

In this case, as a method different from the existing orthogonal multiple access scheme, a non-orthogonal multiple access scheme (NOMA) may be applied.

In this case, referring to FIGS. 7A and 7B, FIG. 7A may be a method based on an orthogonal multiple access method, and FIG. 7B may be a method based on a non-orthogonal multiple access method. Can be. In more detail, as described above, the orthogonal multiple access scheme is a scheme that allocates independent resources for each user so that interference between users does not occur. Alternatively, the non-orthogonal multiple access scheme may be a scheme of allocating a plurality of terminals to the same frequency-time resource as a specific resource region and additionally eliminating interference by using an interference cancellation receiver with a previously considered power ratio. In other words, the non-orthogonal multiple access method can obtain a large bandwidth and is expected to be utilized. More specifically, the non-orthogonal multiple access scheme can transmit signals to a greater number of terminals than the rank of the radio channel by superposing the superposition coding to send signals of the terminals in the same spatial resource. have.

Hereinafter, a method of transmitting and receiving a signal in consideration of a type of a terminal based on a non-orthogonal multiple access scheme will be described.

8 is a diagram illustrating a method of generating beams according to a type in a terminal.

As discussed above, non-orthogonal multiple access schemes may utilize large bandwidths. In addition, the base station may transmit a signal to a plurality of terminals (or users) at the same time using a plurality of antennas.

In this case, as an example, the plurality of terminals may provide various services according to respective types. For example, the use of the Internet of Things (IoT) is increasing recently. That is, utilization of communication between things or communication between things and a base station is increasing. In this case, the communication between the thing and the base station may have a different feature from the existing voice communication or data communication. For example, in the conventional voice communication or data communication, there is a need to perform communication based on an irregular pattern according to the needs of a user who uses a terminal. On the other hand, the communication between the thing and the base station may be the purpose of sharing information about the thing, so only periodic and low data capacity may be needed. In addition, even if communication fails, waiting for the next cycle does not cause a problem even if communication is performed again. For example, communication between a base station and an object such as a sensor that reports climate information may be performed. In this case, the climate change may be reported based on a certain period, and only information having a low data capacity may be transmitted based on a predetermined pattern or a predetermined rule.

That is, the communication characteristic between the thing and the base station may be different from that of the conventional voice communication or data communication.

In this case, as the use of the IoT increases, communication with the thing and communication by the user terminal may coexist in the same base station, and a method of controlling the same may be required.

However, in the existing communication system, there may be a limit in controlling the above-described environment.

More specifically, the conventional downlink multi-user transmission scheme is a closed-loop transmission scheme that uses channel division (Frequency division duplex, FDD) or channel estimation (Time division duplex, TDD) scheme. Could. Therefore, unnecessary feedback overhead or pilot overhead may be excessively large for a user requiring a low transmission speed such as an IoT service. Therefore, in consideration of the features of the IoT service, the communication between the thing and the base station may require an open-loop multi-user transmission scheme unlike the conventional method.

In addition, the existing LTE uses a method of allocating to a user on a resource block (RB) basis. In this way, most resources can be used inefficiently when allocated to a thing requiring a low transmission capacity. This may result in high signaling overhead when allocating to a user in smaller units. Thus, there is a need to allocate resources to users requiring low transmission rates in a new way.

In addition, as described above, the information generated by the thing may be periodic or predictable, and unlike when it is unpredictable when a communication request is required, such as a user, the time and amount of transmission that the thing wants to communicate are determined through a predetermined rule. Communication can be performed. However, existing communication systems do not support communication methods that reflect the characteristics of the IoT.

Therefore, below, the communication method which considered the environment where the above-mentioned thing, communication, and communication with a user terminal coexist is disclosed. In addition, hereinafter, a terminal requiring irregular communication, such as a user terminal, is referred to as a first type terminal or a human type terminal, and a terminal requiring a regular and low data capacity such as an object is referred to as a second type terminal or a machin type terminal.

When the multiple antenna system is applied, multiple ranks may be applied as described above. In this case, as an example, in a multi-antenna system, there may be a channel rank that is not used due to lack of channel information in connection with a closed-loop transmission / reception scheme or is left unused for other reasons. In this case, as an example, the base station may transmit an open-loop transmission and reception method by superpositioning using the remaining rank. In this case, the closed-loop transmission and reception method may be a method of transmitting and receiving a signal based on channel estimation information received based on the reference signal after transmitting a reference signal to the terminal, and using the channel estimation information. Stability of signal transmission and reception can be improved. On the other hand, the open-loop transmission and reception method unilaterally transmits and receives a signal without channel estimation information, and thus, stability may be somewhat reduced.

Therefore, the system supports a first type terminal (or human type terminal) that guarantees a high transmission rate by using instantaneous channel information in a closed-loop transmission and reception method, and uses a 2nd channel information in an open-loop transmission and reception method by A second type terminal (or machine type terminal) receiving transmission at a transmission rate may be supported to simultaneously support a first type terminal and a second type terminal.

More specifically, referring to FIG. 8, a cellular system using multiple antennas (for example, 3GPP LTE and LTE-A systems) may include a user who is distributed in a distributed manner with a base station or an eNodeB 100 connected to an infrastructure. User equipments (UEs) 810, 820, and 830 may be configured.

In this case, as described above, the base station 100 and the plurality of terminals 810, 820, and 830 may have a plurality of antennas.

For example, the base station 100 may have N antennas, and the terminals 810, 820, and 830 may have M antennas. In this case, N and M mean a plurality of numbers and may not mean a specific number.

Also, as an example, the above-described antenna may mean a logical antenna as well as a physical antenna. That is, it may mean the number of paths that can be transmitted or received by being controlled by a baseband processor of the base station 100 or the terminals 810, 820, and 830. In addition, as an example, although the number of physical antenna units such as a hybrid array antenna and the number of paths that can be controlled by the baseband processor may be used, the following description assumes that they are the same for convenience of description.

Referring to FIG. 8, the transmitter 110 of the base station 100 may be configured of a closed-loop NOMA transmitter 111 for a closed-loop transmission and an open-loop NOMA transmitter 112 for an open-loop transmission. Can be. At this time, the closed-loop NOMA transmitter 111 may generate a closed-loop beam based on the instantaneous channel information of the user. That is, it is possible to generate a beam for transmitting to the first type terminal. In this case, the number of generated beams may be Nc, and Nc may be less than or equal to the total number N of antennas.

For example, if the number of users who know the instantaneous channel information is less than N, the number of users who know the instantaneous channel information is greater than N, but if the rank of the channel is less than N or the number of users who know the instantaneous channel information is greater than N, Nc may be less than N, such as when it is better to send to fewer users than N. However, the above-described cases may be one example and may not be limited to the above-described embodiment. That is, Nc may be applied to a case less than or equal to N.

The open-loop NOMA transmitter 112 may generate an open-loop beam using statistical characteristics of the user's channel. In this case, the closed-loop beam may be a first type beam, and the open-loop beam may be referred to as a second type beam. In this case, as an example, after the closed-loop chest is generated first, an open-loop beam may be generated based on the generated closed-loop beam. In this case, the rank of the space spanned from the base station 100 to the closed-loop beam may be Nc, and the rank corresponding to the null space of the closed-loop beam may be N-Nc by the null-rank theorem. At this time, No beams for the open-loop beam may be generated in the N-Nc space.

More specifically, as described above, the rank of the space spanned by the closed-loop beam may be Nc. At this time, Nc closed loop loops

This can be called. At this time,

May be an NX 1 vector. therefore,

The space spanned by may span the Nc-dimensional subspace above the N-dimensional space. In this case, the null-space for the space spanned in the Nc dimension may occupy the N-Nc-dimensional subspace on the N-dimensional. In this case, the above-described open-loop beam may be generated in the N-Nc-dimensional subspace. That is, No open-loop beams may be generated in the N-Nc-dimensional subspace. At this time, the open-loop NOMA transmitter 112 may deliver information to the user using the above-described null space space. That is, the open-loop NOMA transmitter 112 delivers information to the user through the no space using the open-loop beam. In this case, as an example, the open-loop beam may be generated using statistical characteristics of the user channel, which will be described later.

Also, for example, No may be less than or equal to N-NC. For example, a space for a closed-loop beam is first generated, and a channel rank that is left unused due to lack of channel information based on the closed-loop beam space or is not used for another reason is created as an open-loop beam space. , No may be smaller than N-Nc. That is, No may be generated by the maximum N-Nc-dimensional subspace, and is not limited to the above-described embodiment.

Also, as an example, the terminals 810, 820, and 830 may receive a signal transmitted by the base station 100 through a receiver. In this case, as an example, the receiver may include a NOMA receiver. That is, the terminals 810, 820, and 830 may receive a signal transmitted by the base station through the NOMA receiver. In this case, each of the terminals 810, 820, and 830 may know whether to receive in a closed-loop beam or an open-loop beam in advance. In this case, the aforementioned first type terminal may receive a closed-loop beam. In addition, the second type terminal may receive an open-loop beam.

That is, the base station 100 may transmit beams to the first type terminal and the second type terminal through a non-orthogonal multiple access scheme in one resource region. In this case, the base station 100 may first generate closed-loop beams for the first type terminal and generate and allocate open-loop beams to the remaining space in consideration of the null space of the generated closed-loop.

9 is a diagram illustrating a terminal divided into two types.

Referring to FIG. 9, as described above, the terminals may be distinguished from human type first type terminals 910, 920, and 930 and machine type second type terminals 940, 950, and 960.

In this case, as an example, the terminals 910, 920, 930, 940, 950, and 960 may inform the base station 100 of the type for each terminal. In this case, as an example, the terminals 910, 920, 930, 940, 950, and 960 define a field related to a type in a physical uplink shared channel (PUSCH) when the cell is connected to the base station 100. This may provide information on the type to the base station. Also, for example, the base station 100 may track and infer the Quality of Service (QoS) indicator of the PUSCH of the terminals 910, 920, 930, 940, 950, and 960.

Also, as an example, the base station 100 may have a list for first type terminals and list information for second type terminals. The base station 100 may use a different transmission method using a list. That is, the type information of the plurality of terminals 910, 920, 930, 940, 950, and 960 may be information reported to the base station 100 or preset information, and is not limited to the above-described embodiment.

FIG. 10 is a diagram illustrating a resource block (RB) according to two types.

Referring to FIG. 10, it is an exemplary diagram illustrating an example of a resource grid of one resource block (RB) of LTE. In this case, FIG. 10 illustrates a case in which an OFDM symbol includes a general CP. In this case, the downlink slot includes a plurality of OFDM symbols in the time domain and includes a plurality of resource blocks in the frequency domain.

In addition, as many layers as antennas of the base station may be called. In this case, one downlink slot includes 7 OFDM symbols and one resource block includes 12 subcarriers as an example, but is not limited thereto.

Referring to FIG. 10, resource blocks of a base station may be divided into a closed-loop layer as a resource for first type terminals and an open-loop layer as a resource for second type terminals.

That is, the closed-loop beam and the open-loop beam may be allocated together based on a non-orthogonal multiple access scheme based on one resource region. In this case, the space for the closed-loop beam and the space for the open-loop beam may be divided and set in one resource region in consideration of a multi-antenna environment. In this case, Nc closed-loop layers may be included in the space for the closed-loop beam. In this case, Nc may be the number of the closed-loop beams described above. That is, the number of closed-loop layers may be equal to the number of closed-loop beams described above.

Likewise, no open-loop layers may be included in the space for the open-loop beam. In this case, No may be the number of the open-loop beams described above. That is, the number of open-loop layers may be equal to the number of open-loop beams described above.

In addition, each beam may correspond one-to-one with one layer. In this case, as an example, resource allocation for the closed-loop beams may be performed first, and resource allocation for the open-loop beams may be performed in consideration of resource allocation for the generated closed-loop beams. That is, after the space for the closed-loop beam is first set, the space for the open-loop beam may be set.

11 is a diagram illustrating an open-loop beam codebook.

The following describes how the open loop beams are divided in the space for the open-loop beams.

As described above, after the space for the closed-loop beam is set, the space for the open-loop beam may be set. In this case, No open-loop beams may be included in the space for the open-loop beam, and the base station may divide each beam for the second type terminals by using a beam codebook. In this case, as an example, the beam codebook may use a discrete Fourier transform (DFT) basis as shown in Equation 12 below.

[Equation 12]

At this time,

I th beam is the i th column vector of B

A vector set consisting of vectors closest to and may be defined as in Equation 13.

[Equation 13]

In addition, the channel of the second type terminal A may be defined as in Equation (14).

[Equation 14]

At this time,

Is a small-scale (or short-term) fading that changes every coherence time,

Is a large-scale (or long-term) fading part including spatial correlation between the base station and the second type terminal, and the secondary statistical characteristics of the channel,

Can be. At this time, the base station is a secondary channel characteristic of the second type terminal

The second type terminals may be distinguished by using. At this time, if the eigen-value decomposition of the secondary channel characteristics of the second type of terminals is as shown in Equation 15 below.

[Equation 15]

here

Is the NXN Unitary matrix,

Is the NXN diagonal matrix, where the i-th diagonal component is the eigen-value

ego,

to be.

If the above condition is satisfied, the i th eigen-vector,

The space spanned by

It belongs to the following equation (16).

[Equation 16]

Accordingly, each of the second type terminals can obtain which beam corresponds to each secondary channel characteristic. In addition, since only the eigen-vector corresponding to an eigen-value of a predetermined size or more is meaningful, this may be expressed as in Equation 17 below.

[Equation 17]

At this time,

Is the number of meaningful eigen-vectors. That is, the channel of the second type terminal A is

It can be approximated as a channel spanning by. That is, the open-loop beam for each of the second type terminals in the opne-loop beam space may be set based on the secondary channel characteristics. As an example, an approximated channel of the above-described second type terminal A as an open-loop beam

Is a closed-loop beam of the first type terminals

Can be obtained by projecting onto null space of.

That is, the base station may calculate a space for the closed-loop beams and then calculate a null space and allocate the space to the open-loop beams. In this case, referring to FIG. 11, open-loop beam indexes may be selected in a space for the open-loop beams. In this case, the base station may map data symbols to be transmitted through respective open-loop beams to an open-loop layer corresponding to the selected beam index. That is, the base station may allocate respective open-loop beams in the space for the open-loop beams based on the beam index.

12 and 13 illustrate an open-loop beam selection scheme and an embodiment.

As described above, the open-loop beam may be mapped to the corresponding open-loop layer based on the beam index. In this case, the base station may transmit a data symbol using a corresponding open-loop layer.

In this case, as an example, data symbols for the open-loop beam may be transmitted after time-frequency-space hopping or spreading to obtain time-frequency-space diversity. In this case, for example, a hopping pattern or a spreading pattern may be set based on the statistical characteristics of the above-described channel.

For example, referring to FIG. 13, when a base station transmits a data symbol to a terminal based on a single-user (SU), a base station may set and transmit a hopping pattern or a spreading pattern. In addition, the base station may set and transmit a hopping pattern or a spreading pattern to transmit data symbols to a plurality of terminals, respectively, based on a multi-user (MU).

More specifically, referring to FIG. 12, a signal allocated to an open-loop layer may be obtained by a hopping method and a spreading method as described above. In this case, as an example, the closed-loop transmission and reception may estimate an instantaneous channel or determine a modulation and coding scheme (MCS) of a signal to be transmitted through a received channel quality indicator (CQI). That is, the MCS is determined through the feedback information of the closed-loop beams so that transmission and reception of a signal may proceed.

On the other hand, in the open-loop transmission and reception, since there is no estimated instantaneous channel information or CQI, it is necessary to use a pre-promised MCS. That is, since there is no feedback information for the Opne-loop beams, it is necessary to use a predefined or promised MCS scheme. In this case, the MCS may be determined according to various requirements of the network.

For example, the MCS may be determined by measuring an average power and a dispersion value of a signal of a cell specific reference signal (CS-RS) transmitted from a base station by a second type terminal. CS-RS average power

, The variance value is

, A random variable X that satisfies this can be obtained. In this case, when the random variable X is approximated by a gamma distribution, the shape parameter of X is

, The scale parameter is

Can be determined. In this case, the distribution of X may be as shown in Equation 18 below.

Equation 18

At this time, the MCS may use the above-described random variable X, the base station may determine the probability that the transmitted signal is not decoded (outage probability) to be below a predetermined level. That is, the reception power condition for using the i th MCS

Frequency efficiency

When, the optimal MCS can be determined by Equation 19 below.

[Equation 19]

here

Is the outage probability required by the network.

In this case, referring to FIG. 12, diversity gain may be obtained by a hopping method and a spreading method in order to improve the reception signal quality of the open-loop layer.

In this case, as an example, a hopping pattern and a spreading pattern for diversity gain may be determined at the time when the second type terminals associate with the base station. In this case, the hopping pattern and the spreading pattern may be generated at a frequency (OFcarrier) or a time (OFDM symbol). In the second type terminals, the MCS of the received signal may be newly determined according to the hopping pattern and the spreading pattern. For example, when transmitting one data symbol by spreading Y times, the power of the signal is

It can be increased to, so that a new MCS can be obtained.

14 is a flowchart illustrating a flow chart according to an embodiment of the present specification.

The base station may select the first type terminal according to a scheduling algorithm. In this case, as described above, the base station may receive type information from a plurality of terminals or infer type information through QoS. Thereafter, the base station may request uplink reference signals from the first type terminals. That is, the base station may allocate reference signals to the first type terminals and obtain instant channel information based on the reference signals. In this case, reference signals are not allocated to the second type terminals and instantaneous channel information for the second type terminals are not obtained.

Thereafter, the base station may generate a closed-loop transmit beam based on the estimated channel information, and calculate a null space of the generated closed-loop transmit beam space. In addition, the base station may select an open-loop beam index corresponding to the null space. The base station may map and transmit the data symbol to be sent to the open-loop layer corresponding to the selected beam index. In this case, as described above, the base station may use a hopping or spreading method. Thereafter, the base station can transmit the configured closed-loop beam and open-loop beam through the downlink.

15 is a flowchart illustrating a flow chart according to an embodiment of the present specification.

Referring to FIG. 15, the base station may transmit a reference signal to the first type terminals based on the type information about the plurality of terminals (S1510). Next, the base station receives the first type terminals that have received the reference signal. In this case, as described above with reference to FIGS. 7 through 14, the first type terminal is a human type terminal and may be a terminal of a type in which data transmission requires irregularly large capacity. have. In addition, the second type terminal may be a Machin type terminal and may periodically transmit data, and may be a terminal of a type for transmitting low capacity data.

Next, the base station may generate beams based on the received channel estimation information (S1530), and allocate resources for the generated beams (S1540). At this time, as described above with reference to FIGS. May first generate and allocate closed-loop beams transmitted to the first type terminals by using the received channel estimation information, and generate and allocate open-loop beams based on the generated closed-loop beams. In this case, the base station may transmit the closed-loop beams to the first type terminals, and transmit the open-loop beams to the second type terminals. In this case, as described above, the base station may transmit the closed-loop beam and the open-loop beam in one resource region using a non-orthogonal multiple access scheme. In this case, one resource region may be divided into a first space consisting of Nc closed loop beams and a second space consisting of no open loop loops. In addition, the second space may be a space generated by considering the null space of the first space after the first space is generated, as described above.

16 is a block diagram of a base station apparatus and a terminal apparatus according to an embodiment of the present specification. The wireless communication system may include a base station apparatus 100 and a terminal apparatus 200.

In this case, the base station apparatus 100 includes a transmitting module 110 for transmitting a wireless signal, a receiving module 130 for receiving a wireless signal, and a processor 120 for controlling the transmitting module 110 and the receiving module 130. can do. In this case, the base station apparatus 100 may communicate with an external device using the transmitting module 110 and the receiving module 130. In this case, the external device may be a terminal device, and may include at least one of the above-described first type terminal and second type terminal. In addition, the transmission module 110 may include the above-described closed-loop NOMA transmitter and open-loop NOMA transmitter. That is, the base station apparatus 100 may be a device capable of communicating with the terminal apparatus 100 as an external device, and is not limited to the above-described embodiment.

In addition, the terminal device 200 includes a transmitting module 210 for transmitting a wireless signal, a receiving module 230 for receiving a wireless signal, and a processor 220 for controlling the transmitting module 210 and the receiving module 230. can do. In this case, the terminal device 200 may communicate with the base station by using the transmitting module 210 and the receiving module 230. In this case, as an example, the terminal may be at least one of the first type terminal and the second type terminal described above. In addition, the receiving module 230 of the terminal may include the above-described NOMA receiver. That is, the terminal device 200 may be a device capable of communicating with a base station in a wireless communication system, and is not limited to the above-described embodiment.

In this case, as an example, the processor 120 of the base station 100 may transmit a reference signal to the first type terminals using the transmission module 110 based on the type information about the plurality of terminals. In addition, the processor 120 may receive channel estimation information from the first type terminals that have received the reference signal by using the reception module 130. In addition, the processor 120 may generate beams based on the received channel estimation information, and allocate resources for the beams. In this case, for example, when resources for beams are allocated, closed-loop beams for first type terminals are first generated, and open-loop beams for second type terminals are generated based on the generated closed-loop beams. It can be generated non-orthogonal. In this case, as an example, the closed-loop beams and the open-loop beams may be allocated together non-orthogonally in one resource region. In addition, as described above, a single space may be divided into a first space including Nc closed loop beams and a second space including no open-loop beams based on multiple antennas, and a second space. May be set based on the first space, as described above.

In addition, although each configuration is listed based on the base station with respect to the above configuration, the same configuration may be applied to the first type terminal and the second type terminal.

More specifically, the first type terminal may receive a closed-loop beam transmitted by the base station after transmitting the channel estimation information to the base station by receiving a reference signal from the base station. In this case, the first type terminal may receive only the closed-loop beam set by the base station as described above.

In addition, the second type terminal may not be allocated a reference signal to the base station, and as described above, may receive an open-loop beam transmitted by the base station. That is, in relation to the above-described configuration, the base station, the first type terminal, and the second type terminal in the wireless communication system may be a system that operates in association with each other, and are not limited to the above-described embodiment.

Embodiments of the present invention described above may be implemented through various means. For example, embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.

For implementation in hardware, a method according to embodiments of the present invention may include one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), and Programmable Logic Devices (PLDs). It may be implemented by field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, the method according to the embodiments of the present invention may be implemented in the form of a module, a procedure, or a function that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

The detailed description of the preferred embodiments of the invention disclosed as described above is provided to enable any person skilled in the art to make and practice the invention. Although the above has been described with reference to the preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. I can understand that you can. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. In addition, while the preferred embodiments of the present specification have been shown and described, the present specification is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present specification claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or prospect of the present specification.

In the present specification, both the object invention and the method invention are described, and the description of both inventions may be supplementarily applied as necessary.

A method for allocating resources and a device for the same in a wireless communication system using multiple antennas as described above have been described with reference to an example applied to a 3GPP LTE system. .

Claims (15)

1. In the method for allocating resources in a wireless communication system using multiple antennas,

   Transmitting a reference signal to first type terminals based on the type information about the plurality of terminals;

   Receiving channel estimation information from the first type terminals receiving the reference signal;

   Generating beams based on the received channel estimation information; And

   Allocating resources for the generated beams;

   When allocating resources for the beams, first type beams for the first type terminals are first generated and allocated, and second type beams for the second type terminal are generated based on the generated first type beams. A method of resource allocation, generated and allocated non-orthogonal.
2. The method of claim 1,

   And the first type beams and the type 2 beams are allocated together non-orthogonally in one resource region.
3. The method of claim 2,

   The one resource region is divided into a first space including Nc of the first type beam and a second space including No of the second type beam based on the multiple antennas. Assignment method.
4. The method of claim 3, wherein

   And the second space is generated based on the generated first space after the first space is generated.
5. The method of claim 3, wherein

   And the second space is divided based on a beam codebook.
6. The method of claim 3, wherein

   The No second type beams included in the second space are transmitted based on a hopping pattern.
7. The method of claim 3, wherein

   And the No second type beams included in the second space are transmitted based on a spreading pattern.
8. The method of claim 1,

   And the first type beam is a closed-loop beam and the second type beam is an open-loop beam.
9. The method of claim 1,

   The first type terminal is a human type terminal, and the second type terminal is a machine type terminal.
10. The method of claim 1,

    Receiving type information for each terminal from the plurality of terminals; resource allocation method further comprising.
11. The method of claim 10,

    Type information for the terminal is received in the physical uplink shared channel (Physical uplink shared channel, PUSCH) received.
12. A base station for allocating resources in a wireless communication system using multiple antennas,

    A receiving module for receiving the information from an external device;

    A transmission module for transmitting information from an external device; And

    A processor for controlling the receiving module and the transmitting module,

    The processor,

    Transmitting a reference signal to first type terminals based on the type information of a plurality of terminals using the transmission module,

    Receiving channel estimation information from the first type terminals receiving the reference signal by using the reception module,

    Generate beams based on the received channel estimation information,

    Allocate resources for the generated beams,

    When resources for the beams are allocated, first type beams for the first type terminals are first generated and allocated, and second type beams for the second type terminal are generated based on the generated first type beams. A base station apparatus, generated and assigned non-orthogonal.
13. The method of claim 12,

    And the first type beams and the type 2 beams are allocated together non-orthogonally in one resource region.
14. The method of claim 13,

    Wherein the one resource region is divided into a first space including Nc of the first type beam and a second space including No of the second type beam based on the multiple antennas. Device.
15. The method of claim 14,

    And the second space is generated based on the generated first space after the first space is generated.

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