KR20180108953A - Method and apparatus of retransmission for punctured region on New Radio wireless communications - Google Patents

Abstract

The present invention provides a rapid retransmission method according to puncturing determined in a 3GPP NR system, and a device thereof. According to an embodiment of the present invention, the method for allowing a transmitter to transmit a signal comprises the following steps of: setting a puncturing position; determining an influence block according to the set puncturing position; retransmitting the determined influence block; and processing retransmitted information.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method and apparatus for retransmission of a punctured region on a New Radio radio communication system,

The present invention provides a fast retransmission method according to puncturing determined in a 3GPP NR system.

One embodiment provides a method for a sender to transmit a signal comprising the steps of establishing a puncturing position, determining an impact block according to a puncturing location that has been set, retransmitting the determined impact block, and processing the retransmitted information And to provide a method and apparatus.

1 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.
2 is a block diagram illustrating a configuration of a user terminal according to another embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Herein, the MTC terminal may mean a terminal supporting low cost (or low complexity) or a terminal supporting coverage enhancement. In this specification, the MTC terminal may mean a terminal supporting low cost (or low complexity) and coverage enhancement. Alternatively, the MTC terminal may refer to a terminal defined in a specific category for supporting low cost (or low complexity) and / or coverage enhancement.

In other words, the MTC terminal in this specification may mean a newly defined 3GPP Release-13 low cost (or low complexity) UE category / type for performing LTE-based MTC-related operations. Alternatively, the MTC terminal may support enhanced coverage over the existing LTE coverage or a UE category / type defined in the existing 3GPP Release-12 or lower that supports low power consumption, or a newly defined Release-13 low cost low complexity UE category / type.

The wireless communication system in the present invention is widely deployed to provide various communication services such as voice, packet data and the like. A wireless communication system includes a user equipment (UE) and a base station (BS, or eNB). The user terminal in this specification is a comprehensive concept of a terminal in wireless communication. It is a comprehensive concept which means a mobile station (MS), a user terminal (UT), an SS (User Equipment) (Subscriber Station), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B (eNB), a sector, a Site, a BTS A base transceiver system, an access point, a relay node, a remote radio head (RRH), a radio unit (RU), and a small cell.

That is, the base station or the cell in this specification is interpreted as a comprehensive meaning indicating a partial region or function covered by BSC (Base Station Controller) in CDMA, NodeB in WCDMA, eNB in LTE or sector (site) And covers various coverage areas such as megacell, macrocell, microcell, picocell, femtocell and relay node, RRH, RU, and small cell communication range.

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. i) the device itself providing a megacell, macrocell, microcell, picocell, femtocell, small cell in relation to the wireless region, or ii) indicating the wireless region itself. i indicate to the base station all devices that are controlled by the same entity or that interact to configure the wireless region as a collaboration. An eNB, an RRH, an antenna, an RU, an LPN, a point, a transmission / reception point, a transmission point, a reception point, and the like are exemplary embodiments of a base station according to a configuration method of a radio area. ii) may indicate to the base station the wireless region itself that is to receive or transmit signals from the perspective of the user terminal or from a neighboring base station.

Therefore, a base station is collectively referred to as a base station, collectively referred to as a megacell, macrocell, microcell, picocell, femtocell, small cell, RRH, antenna, RU, low power node do.

Herein, the user terminal and the base station are used in a broad sense as the two transmitting and receiving subjects used to implement the technical or technical idea described in this specification, and are not limited by a specific term or word. The user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word. Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

There are no restrictions on multiple access schemes applied to wireless communication systems. Various multiple access schemes such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM- Can be used. An embodiment of the present invention can be applied to asynchronous wireless communication that evolves into LTE and LTE-advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB. The present invention should not be construed as limited to or limited to a specific wireless communication field and should be construed as including all technical fields to which the idea of the present invention can be applied.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used.

In systems such as LTE and LTE-advanced, a standard is constructed by configuring uplink and downlink based on a single carrier or carrier pair. The uplink and the downlink are divided into a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel, a Physical Uplink Control CHannel (PUCCH), an Enhanced Physical Downlink Control Channel (EPDCCH) Transmits control information through the same control channel, and is configured with data channels such as PDSCH (Physical Downlink Shared CHannel) and PUSCH (Physical Uplink Shared CHannel), and transmits data.

On the other hand, control information can also be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

The wireless communication system to which the embodiments are applied may be a coordinated multi-point transmission / reception system (CoMP system) or a coordinated multi-point transmission / reception system in which two or more transmission / reception points cooperatively transmit signals. antenna transmission system, or a cooperative multi-cell communication system. A CoMP system may include at least two multipoint transmit and receive points and terminals.

The multi-point transmission / reception point includes a base station or a macro cell (hereinafter referred to as 'eNB'), and at least one mobile station having a high transmission power or a low transmission power in a macro cell area, Lt; / RTI >

Hereinafter, a downlink refers to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink refers to a communication or communication path from a terminal to a multiple transmission / reception point. In the downlink, a transmitter may be a part of a multipoint transmission / reception point, and a receiver may be a part of a terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, EPDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH, EPDCCH and PDSCH are transmitted and received'.

In the following description, an indication that a PDCCH is transmitted or received or a signal is transmitted or received via a PDCCH may be used to mean transmitting or receiving an EPDCCH or transmitting or receiving a signal through an EPDCCH.

That is, the physical downlink control channel described below may mean a PDCCH, an EPDCCH, or a PDCCH and an EPDCCH.

Also, for convenience of description, EPDCCH, which is an embodiment of the present invention, may be applied to the portion described with PDCCH, and EPDCCH may be applied to the portion described with EPDCCH according to an embodiment of the present invention.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The eNB performs downlink transmission to the UEs. The eNB includes a physical downlink shared channel (PDSCH) as a main physical channel for unicast transmission, downlink control information such as scheduling required for reception of a PDSCH, A physical downlink control channel (PDCCH) for transmitting scheduling grant information for transmission in a Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

In NR, three service scenarios are assumed, eMBB providing large capacity high-speed communication environment, mMTC for multi-small terminal service, and URLLC requiring high reliability and low transmission delay unlike the existing 3GPP LTE / LTE-A. Communication technologies for URLLC services and communication technologies capable of efficiently supporting these services have been proposed. As one of the important operations for this, it has been suggested that a packet for URLLC service can intercept and transmit an existing configured signal resource for fastest service transmission. As a result, a form in which a packet of a specific resource location among existing eMBB resources is removed and a URLLC packet is transmitted on the eMBB resource is agreed, and this is expressed as puncturing in the case of an eMBB. For the eMBB user who lost the signal due to puncturing, it was agreed to provide indication information to know or guess the location of the punctured and punctured signal.

The prior art is a method for allowing the affected eMBB terminal to erase the punctured portion and to recover the maximum information through the erasure processing. This method provides maximum information reliability without changing the existing eMBB operation. However, when there is a large number of punctured information, it is difficult to expect the information restoration by the error correcting code which is already applied. HARQ processing resources and communication resources for retransmission are required. Therefore, if the URLLC is eroded and the erosion is persistent, the existing operation will incur large overhead.

The present invention provides a block retransmission method in which a recipient who knows punctured signal resource location information among transmission signals can communicate with lower processing complexity and delay as compared with the prior art. This allows the receiver to receive and recover faster retransmission information for lost blocks due to puncturing.

The present invention can be roughly divided into (1) a puncturing position setting method , (2) a method of determining an influence block according to a set puncturing position , (3) a method of retransmitting a determined influence block , and (4) Respectively. Each method does not always have to be applied at the same time, but can be applied independently and classified according to the purpose of the communication system. And that the terms proposed in the invention are intended to illustrate the role of the actual object and not to limit the scope of the technology.

Before describing the operation of the invention, some matters to be assumed in the system to which the invention applies are described.

Assumption 1. First, it is assumed that transmission is performed in TB (Transmission Block) units, and that TB is composed of k CBs (Code Blocks). Several CBs within the same TB come together to form a CBG (Code-Block Group), so CBG is a subset of TB. One TB is assumed to be MECE (Mutually-Exclusive, Collectively Exhaustive) with m CBG. When receiving TB, it is assumed that the reception success or failure is discriminated for each CB, and it is assumed that all CBs send ACK to CBG that successfully received and NACK to CBG that contains CB of failed CB. As a result, ACK / NACK feedback is transmitted for one TB and m bits at the receiving end.

Assumption 2. At the transmitting end, whether or not to puncture is transmitted to the receiving end. At this time, it is assumed that, through the transmission information, the transmitting and receiving end can explicitly or implicitly know which portion is punctured when the transmitted communication signal is mapped to the communication resource, that is, the portion to be discarded from the receiving end .

(1) How to set the puncturing position :

Since both the transmitting end and the receiving end know the positions of the TBs and the positions of the CBs on the communication resources, in the transmitting end, puncturing is performed in a form that reduces the number of CBs and CBGs affected by puncturing You can decide. As a concrete example, there is a method of mapping the CBs of the logically identical CBGs in a sequential manner, and sequentially performing puncturing as necessary from the beginning.

There are several approaches to the practical method of performing logical sequential puncturing here. Physical continuity can be mapped to logical continuity, and interleaving information can be completely shared. In this case, since the amount of information and the number of puncturing patterns to be supported can be increased, a mapping method capable of performing puncturing in which a plurality of bits can be connected to one CB can be used while reducing the amount of information.

(2) Influence on the set puncturing position How to determine the block :

If the puncturing method is determined by the method proposed in (1) or another method, the transmitting end can specify the CBs affected by the puncturing method. Actually, these puncturing patterns can also be precisely specified because some or all of these CBs can be in a punctured form and since it is the transmitting end that composes the transmission frame. This information is transmitted accurately by the assumption at the receiving end.

After determining the punctured CB, the transmitting and receiving end can determine the affected block in the following manner. Here, the block means CB and CBG, and the invention encompasses both of them.

The CB of the punctured resource signaled by RRC or DCI, or CB of more than or equal to threshold value t (or more) defined by the implicit / standard, is determined as an influence block, . Where threshold t may be signaled as a direct value, but may also be determined mathematically with parameters such as CB length, CBG length, MCS level, and other values that can be signaled to control it.

In a technical sense, t is closely related to the error correction capability and channel condition of the code block. That is, the system can set a large t value if the current error correction coding system can secure a sufficiently large error correction capability for the channel condition. This can reduce the amount of retransmission by reducing the number of affected blocks, but in the absence of puncturing, the amount of channel transmission is reduced.

(3) Method of retransmitting the determined influence block :

If the threshold can be reasonably determined, the transmitter can guess that the affected block will send a NACK regardless of whether ACK / NACK is being fed back at the receiving end. Therefore, if there is an influence block, the transmitting end can immediately retransmit the influence block without waiting for the feedback information. The transmitting terminal may retransmit the signal by signaling whether or not the retransmission is possible, or may determine that an implicit agreement has been made, and may retransmit the signal whether the retransmission is not performed or not.

The retransmission may be performed in CB units or in CBG units. In fact, even if a CBG is an influence block, CBs may contain normally received CBs, so the total retransmission amount is much smaller when CB is performed. However, since the existing system manages the retransmission in the CBG unit, the retransmission performed in the CBG unit increases the retransmission amount but has a less influence on the existing operation.

Specifically, since the degree of the defect is known, the retransmission method may be defined in detail. For example, by applying an Incremental Redundancy (IR) retransmission scheme to support scalability in the redundancy amount, retransmission amount can be adjusted according to the number of punctured resources. In this method, a number of values t1, t2, t3, etc., which depend on t, which is a threshold value explicitly or implicitly defined, are generated between the transmitting and receiving ends, and the defect level is classified through each of them, You can specify the amount. For example, if t is determined, t1 = t, t2 = 2t, t3 = 3t, or the like, or t1 = t, t2 = t / 2, t3 = t / 3.

Another consideration when determining retransmissions is that the retransmission information is not included in the next puncturing region. For example, if the puncturing is logically performed in the front section, the retransmission information may be logically packed from the rear section, and the new information may be arranged in the front section and then transmitted.

(4) Method for processing retransmitted information :

According to the methods (3) and (2) defined in the specification, it can be known at the receiving end which information is to be retransmitted at what point. Therefore, if the puncturing is confirmed at the receiving end, the HARQ ACK / NACK can be fed back after receiving the retransmission information. In fact, in the next generation communication system, since the Asynchronous HARQ is supported, the feedback timing can be adjusted and the receiving terminal can grasp the fact that the transmitting terminal will perform the retransmission, so that the transmitting terminal can predict that the timing information will be modified.

At this time, some or all of the information to be retransmitted may again be punctured. This may or may not be retransmitted again in the next frame, so that the HARQ ACK / NACK can be defined to be sent immediately after the first retransmission, or it can be defined to wait until the entire retransmission is complete before sending. Waiting only the first retransmission can guarantee delay performance, and waiting for completion of all retransmissions guarantees quality. In any case, if the time is defined, the transmitting end can accurately know the HARQ ACK / NACK feedback time point without special signaling of the receiving end.

By the method provided by the present invention, the recipient can communicate his missing data by puncturing with lower processing complexity and delay compared to existing techniques. This reduces the number of HARQ processes that are processed on average, and can also increase throughput by improving overall retransmission.

1 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.

Referring to FIG. 1, a base station 1000 according to another embodiment includes a control unit 1010, a transmission unit 1020, and a reception unit 1030.

The control unit 1010 performs a block retransmission method in which a receiver who knows the punctured signal resource position information among the transmission signals required to perform the above-described present invention can communicate with a lower processing complexity and delay Thereby controlling the overall operation of the base station.

The transmitting unit 1020 and the receiving unit 1030 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to and from the terminal.

2 is a diagram illustrating a configuration of a user terminal according to another embodiment.

2, a user terminal 1100 according to another embodiment includes a receiving unit 1110, a control unit 1120, and a transmitting unit 1130.

The receiving unit 1110 receives downlink control information, data, and messages from the base station through the corresponding channel.

The controller 1120 also performs a block retransmission method in which a receiver who knows the punctured signal resource position information among the transmission signals required to perform the above-described present invention can communicate with a lower processing complexity and delay than the conventional technique Thereby controlling the overall operation of the terminal.

The transmitter 1130 transmits uplink control information, data, and a message to the base station through the corresponding channel.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (1)

In a method for a transmitter to transmit a signal,
Setting a puncturing position;
Determining an influence block according to the puncturing position set;
Retransmitting the determined influence block; And
And processing the retransmitted information.

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