KR20100094963A - Method for performing hybrid automatic repeat request operation in wireless mobile communication system - Google Patents

Abstract

PURPOSE: A HARQ(Hybrid Automatic Repeat reQuest) operation method in a wireless mobile communication system is provided to minimize the power consumption by reducing the number of subframes. CONSTITUTION: A transmission stage transmits the data burst allocation information and the DL data burst in a first DL(Down Link) subframe(300) of i-th frame. A reception stage transmits the HARQ feedback through the UL frequency bandwidth in a fifth UL(Up Link) subframe of i-th frame. The transmission stage retransmits the data burst according to the HARQ feedback from a first DL subframe(320) of i+1-th frame.

Description

METHODO FOR PERFORMING HYBRID AUTOMATIC REPEAT REQUEST OPERATION IN WIRELESS MOBILE COMMUNICATION SYSTEM}

The present invention relates to a wireless mobile communication system, and more particularly, to a method of performing a hybrid automatic repeat request (HARQ) operation in a wireless mobile communication system.

The wireless mobile communication system has been developed in the form of providing various services such as broadcasting, multimedia image, multimedia message to the user. In particular, next generation wireless mobile communication systems are being developed to provide data services of 100 Mbps or more for users moving at high speed, and 1 Gbps or more data services for users moving at low speed.

In a wireless mobile communication system, a base station (BS) and a mobile station (MS) are required to reduce control overhead and short latency in order to transmit and receive reliable data at high speed. A hybrid automatic repeat request (HARQ) scheme may be considered as a method for reducing the control overhead and supporting short latency.

In a wireless mobile communication system using the HARQ scheme, when a transmitting end transmits a signal including data, the receiving end transmits an acknowledgment (ACK) or a negative acknowledgment (NACK) indicating whether the data is normally received to the transmitting end. . The transmitting end initially transmits new data according to the reception of the ACK or NACK or retransmits previously transmitted data according to the HARQ scheme. Here, the HARQ scheme may be a Chase Combining (CC) scheme or an Incremental Redundancy (IR) scheme.

In the conventional HARQ scheme, since the transmission / reception operation is performed in units of frames, the short latency cannot be satisfied. Therefore, there is a need for a new frame structure for transmitting and receiving a signal that satisfies shorter latency and a HARQ operation timing structure according to the new frame structure.

The present invention provides a method of controlling HARQ operation in a wireless mobile communication system.

The present invention provides a method for determining timing for data burst transmission, HARQ feedback signal transmission and retransmission in a wireless mobile communication system.

The present invention provides a method for flexibly determining the HARQ operation timing according to the length of a data burst transmission interval and system capability in a wireless mobile communication system.

A first method according to a preferred embodiment of the present invention; A method for operating a hybrid automatic repeat request (HARQ) in a wireless mobile communication system using frames each consisting of a plurality of subframes according to a frequency division multiplexing (FDD) method for communication,

determining a HARQ timing including DL data burst for DL HARQ transmission and transmission time points of HARQ feedback, corresponding to data burst allocation information in an l- th downlink (DL) subframe of an i-th frame; and the determined HARQ Performing a HARQ operation according to timing. Here, at least one frame index and at least one subframe index indicating the HARQ timing are determined by using the i and l .

According to another embodiment of the present invention, a method of operating a hybrid automatic repeat request (HARQ) in a wireless mobile communication system using a frame composed of a plurality of subframes for communication,

In response to the data burst allocation information in the l- th downlink (DL) subframe of the i-th frame, it includes UL data burst and ULQ burst transmission time for uplink (UL) HARQ transmission and retransmission timing of the data burst. And determining a HARQ timing, and performing a HARQ operation according to the determined HARQ timing. Here, at least one frame index and at least one subframe index indicating the HARQ timing are determined by using the i and l .

According to the present invention, by flexibly configuring the HARQ operation timing in a wireless mobile communication system, different frame configuration methods, various ratios of downlink (DL) and uplink (UL) according to system bandwidth, and support of legacy systems are provided. HARQ transmission can be flexibly performed according to the scheme. In addition, it may support a synchronized relationship between the DL and the UL.

As described above, the synchronized relationship can reduce the number of subframes that the receiver should monitor, thereby minimizing power waste. In addition, by using a predefined operation timing, there is an advantage that the terminal has a high degree of freedom for communicating with other systems.

1 is a diagram illustrating an example of a superframe structure of the FDD scheme according to an embodiment of the present invention.
2 is a diagram illustrating an example of a superframe structure in a TDD mode according to a preferred embodiment of the present invention.
3 is a diagram illustrating a HARQ operation timing structure for DL data burst transmission in an FDD scheme according to an embodiment of the present invention.
4 is a diagram illustrating a HARQ operation timing structure for UL data burst transmission in an FDD scheme according to an embodiment of the present invention.
5 is a diagram illustrating a HARQ operation timing structure for DL data burst transmission in a TDD mode according to an embodiment of the present invention.
6 illustrates a HARQ operation timing structure for UL data burst transmission in the TDD mode according to an embodiment of the present invention.
7 is a diagram illustrating a HARQ operation timing structure according to a DL data burst transmission in a TDD mode in a mode where two systems coexist according to an embodiment of the present invention.
8 illustrates a HARQ operation timing structure according to UL data burst transmission in TDD mode in a mode in which two systems coexist according to an embodiment of the present invention.
9 is a diagram illustrating a HARQ operation timing structure for DL data burst transmission in an FDD scheme according to another embodiment of the present invention.
10 illustrates a HARQ operation timing structure for DL data burst transmission in the TDD mode according to another embodiment of the present invention.
11A and 11B, 12A and 12B, and 13A and 13B illustrate a HARQ operation timing structure according to ratios of DL and UL.
14 illustrates a frame structure of a wireless mobile communication system supporting a repeater according to a preferred embodiment of the present invention.
15A and 15B illustrate an example of a RS frame structure in a TDD mode according to an embodiment of the present invention.
16A and 16B illustrate an HARQ operation timing structure for an odd-hop relay station in accordance with an embodiment of the present invention.
17 illustrates a HARQ operation timing structure for an even-hop relay station according to an embodiment of the present invention.
18 and 19 show an operation flowchart between a base station and a terminal for a DL and UL HARQ timing structure according to a preferred embodiment of the present invention, respectively.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, only parts necessary for understanding the operation of the present invention will be described, and other background art will be omitted so as not to distract from the gist of the present invention.

In this specification, a frequency division duplex (FDD) mode or a time division duplex (TDD) method or H-FDD (H-FDD) is referred to as 'H-'. In the wireless mobile communication system to which the FDD 'mode and the FDD mode and the TDD mode are applied, the present invention proposes a HARQ operation method having a constant HARQ retransmission delay time. The frame structure used in the wireless mobile communication system to which the TDD mode or the H-FDD mode is applied may have various resource occupancy rates between the downlink period and the uplink period. That is, the corresponding relationship between uplink and downlink may have a symmetrical or asymmetrical form.

Hereinafter, an operation of transmitting and receiving a signal between a base station (BS) and a mobile station (MS) in accordance with a HARQ scheme under a super frame structure will be described. Each superframe includes at least one frame, and each frame includes at least one subframe. A term having the same meaning as the subframe includes a time slot. Each time slot or each subframe includes at least one orthogonal frequency division multiple access (OFDMA) symbol.

In one embodiment, each of the base station and the terminal is a controller for generating and analyzing data burst allocation information and for determining a time to perform HARQ transmission according to the frame structure and HARQ operation timing to be described later, and at the timing under the control of the controller At least one HARQ processor for generating and analyzing data bursts and HARQ feedback, and a transceiver for transmitting and receiving the data burst allocation information and data bursts and HARQ feedback. As an example, the data burst allocation information may be transmitted in the form of an Advanced MAP (A-MAP) Information Element (IE) indicating resource allocation, and the data burst is HARQ sub-generated according to HARQ operation. It may be transmitted in the form of a packet (Subpacket).

1 is a diagram illustrating an example of a superframe structure of the FDD scheme according to an embodiment of the present invention.

Referring to FIG. 1, the superframe 100 is composed of four frames, and each frame 110 is composed of eight subframes. In the FDD scheme, a downlink (DL) subframe 120 used for transmission from a base station to a terminal and an uplink (UL) subframe 130 used for transmission from a terminal to a base station are respectively provided. Operates in different frequency bands.

2 is a diagram illustrating an example of a frame structure of a TDD mode according to a preferred embodiment of the present invention.

Referring to FIG. 2, the superframe 200 is composed of four frames, and each frame 210 is composed of eight subframes. In the TDD mode, a predetermined number of subframes are operated as DL subframes in each frame 210, and the remaining number of subframes are operated as UL subframes. In FIG. 2, DL: UL = 5: 3, which shows five DL subframes within a DL period and three UL subframes within a UL period. A TTG (Transmit / Receive Transition Gap) exists between a DL subframe and a subsequent UL subframe, and a Receive / transmit Transition Gap (RTG) exists between a UL subframe and a subsequent DL subframe.

In FIGS. 1 and 2, the superframe is composed of four frames and each frame is composed of eight subframes. However, the number of frames N and the number of subframes F are illustrated and described. May have different values according to the bandwidth and subcarrier spacing of the wireless mobile communication system. For example, in a wireless mobile communication system of an Orthogonal Frequency Division Multiplexing (OFDM) / OFDMA system having 5, 10, and 20 MHz (hertz) channel bandwidth, the number of subframes per frame may be eight. In case of an OFDM / OFDMA wireless mobile communication system having a channel bandwidth of 8.75 MHz, the number of subframes per frame is 7, and in an OFDM / OFDMA wireless mobile communication system having a channel bandwidth of 7 MHz, The number of subframes per frame may be six. In addition, one BW may have various number of subframes according to CP length.

In the HARQ scheme, a timing of initial transmission and a timing of retransmission may have a predetermined correspondence relationship, and this correspondence relationship is called an HARQ operation timing structure or an HARQ interlace. The HARQ operation timing structure or HARQ interlace includes a relationship between a subframe in which a MAP message including resource allocation information (ie, control information) is provided and a subframe in which a signal is transmitted corresponding thereto, and a subframe in which the signal is transmitted. And a relationship between a subframe in which feedback corresponding thereto is transmitted and a subframe in which the feedback is transmitted and a subframe in which data corresponding thereto is initially transmitted or retransmitted. This will be described below.

(1) Data burst allocation information (Information Element (IE)): Indicates allocation of DL data burst or UL data burst and is provided through a DL subframe.

(2) Data burst: The transmitting end transmits the data burst using the allocated resources according to the data burst allocation information.

(3) HARQ feedback on data burst transmission: The receiver transmits an acknowledgment (ACK) or a negative-acknowledgement (NACK) according to whether the data burst is determined as an error.

(4) Initial Transmission or Retransmission of Data Burst According to HARQ Feedback: When the HARQ feedback is NACK, the transmitter retransmits the data burst. In this case, allocation information for retransmission may be additionally provided. In contrast, when HARQ feedback is ACK, a new data burst can be initially transmitted.

The HARQ scheme may be classified into an asynchronous HARQ and an synchronous HARQ. In the case of asynchronous HARQ, it is necessary to define the HARQ operation timing structure for (1) to (3), and in the case of synchronous HARQ, the definition of the HARQ operation timing structure for (1) to (4) is necessary. In order to define the HARQ operation timing, a constant correspondence between at least one subframe in the DL period and at least one subframe in the UL period is required.

Hereinafter, HARQ operation timing in the FDD communication mode and the TDD communication mode will be described in detail.

3 is a diagram illustrating a HARQ operation timing structure for DL data burst transmission in an FDD scheme according to an embodiment of the present invention. As shown, reference is made to the FDD frame structure of FIG. 1. Here, assuming that F = 8, N = 4, transmission and reception processing time (Tx / Rx processing time) for the data burst are 3 subframes, respectively, DL HARQ feedback offset (z) = 0 and DL HARQ transmission offset ( u) = 0. Herein, the transmission processing time refers to the time required for the transmitter to send the next data after receiving the HARQ feedback, and the reception processing time refers to the time required for transmitting the HARQ feedback after the receiver receives the data.

Referring to FIG. 3, the transmitting end transmits data burst allocation information and DL data burst through DL frequency band in DL subframe 300 of frame i and frame 5 receives a UL subframe 5 of subframe i of frame i. In step 310, HARQ feedback is transmitted through the UL frequency band. Retransmission of the data burst according to the HARQ feedback is performed in the DL subframe 320 of frame i + 1 by the transmitter, and the feedback thereof is performed in DL subframe 330 of frame 5 of the i + 1 frame. Is done.

Referring to Table 1 again, the subframe index n through which HARQ feedback is transmitted is determined as {ceil (1 + 4) mod 8} = 5, and the frame index j through which HARQ feedback is transmitted. Is determined by {i + floor (ceil (1 + 4) / 8) +0} mod 4 = i, and the frame index k at which the HARQ data burst is retransmitted is {j + floor ((5 + 4) / 8) + 0} Determined by mod 4 = i + 1. The ceil function rounds up the value after the decimal point. The Floor function rounds down the value below the decimal point.

Table 1 below shows an embodiment of a DL HARQ operation timing structure of the FDD scheme. The following table shows transmission times of at least one of an allocated A-MAP IE including data burst allocation information, a HARQ subpacket including a data burst, HARQ feedback including ACK and / or NACK, and a HARQ retransmission subpacket. It can be used to determine, of course, the present invention is not limited by the following table.

In Table 1, N denotes the number of frames constituting one superframe, and 4 when each superframe consists of four frames. F denotes the number of subframes constituting one frame. . For example, N = 4 and F = 8 in the 5/10/20 MHz bandwidth. And i, j and k denote DL frame index or UL frame index, l denotes an index of DL subframe where data burst allocation information is provided, and m denotes an index of DL subframe where data burst transmission starts. N means an index of a UL subframe in which HARQ feedback is transmitted for transmission of a data burst. In addition, z means a DL HARQ feedback offset, and u means a DL HARQ Tx offset. Where z and u are in frame units. Therefore, i = 0,1, ..., N-1, j = 0,1, ..., N-1, l = 0, N _A-MAP , ..., N _A-MAP (ceil ( F / N _A-MAP ) -1), n = 0,1, ..., F-1, m = 0,1, ..., F-1, z = 0,1, ..., z _max -1, and u = 0,1, ..., u _max -1.

N _{A - MAP} means a period in subframe units in which data burst allocation information is provided. The data burst assignment information is conveyed in a conventional MAP message or in an advanced MAP message used in an improved system. N _{A - MAP} = 1 when data burst allocation information is provided in every DL subframe, and N _{A - MAP} = 2 when data burst allocation information is provided in two DL subframe intervals. When N _{A - MAP} = 2, l = 0, 2, ..., 2 (ceil (F / 2) -1).

In the DL HARQ transmission / reception of the FDD scheme shown in FIG. 3, F = 8, N = 4, z = 0, u = 0. i times assigned DL data burst is provided by the time l DL subframe 300 of the frame information indicates the time DL subframe m the i-th frame. When data burst allocation information is provided in every DL subframe (ie, N _{A - MAP} = 1), the data burst allocation information provided in each DL subframe indicates a data burst transmission in which transmission starts in the corresponding DL subframe. M becomes 'l'. On the other hand, if two DL subframes each being provided with a data burst allocation information (i.e., N _{A -} = _MAP 2), l number of data burst allocation information provided from the sub-frame number is l DL sub-frame and the l +1 times the sub Indicates transmission of a data burst at which transmission begins in a frame. That is, m indicates a value of one of 'l' or 'l + 1', and relevance information indicating this is indicated through data burst allocation information.

The data burst indicated by the data burst allocation information may be transmitted through one or more subframes, and the length of a transmission time interval (TTI) of the data burst starting transmission in DL subframe m is N _TTI. It is called. That is, N _TTI refers to the number of subframes occupied by the data burst, and as an example, information on the N _TTI may be predetermined or indicated by data burst allocation information. N _TTI = 1 when the data burst occupies one subframe and N _TTI = 4 when occupying four subframes.

HARQ feedback for the data burst started in DL subframe m of frame i is transmitted in UL subframe n of frame j. N is determined by Equation 1 below by the subframe index m through which the data burst is transmitted.

The UL frame index j is determined by the subframe index m and the frame index i through which the data burst is transmitted. In this case, a frame offset is generated by a time interval between when the transmission of the data burst ends and when HARQ feedback is transmitted. Here, the time interval is defined as Gap1 and is defined by Equation 2 below.

Here, N _TTI is the length of data burst transmission interval (subframe unit) according to DL HARQ operation, and F is the number of subframes constituting each frame. In the FDD system, since each link period is continuous, Gap1 is determined by the DL burst transmission period and the number of subframes in the frame regardless of the subframe index.

In the DL HARQ, the value of the DL HARQ feedback offset z is determined such that Gap1 of Equation 2 is not smaller than (ie, greater than or equal to) the reception processing time. For example, z = 0 if Gap1 is not less than the receive processing time, while z = 1 if Gap 1 is less than the receive processing time. Here, the z value is adjusted such that HARQ feedback is transmitted in the same subframe index of the delayed frame. That is, the z value means an offset in units of frames, and does not mean a change in the subframe index.

When z thus determined is considered, j becomes Equation 3 below.

When retransmitting a DL data burst according to asynchronous HARQ, the retransmission time point of the DL data burst is indicated by a retransmission indicator included in the data burst allocation information. When retransmitting a DL data burst in consideration of synchronous HARQ, the retransmission of the DL data burst is performed in subframe m of frame k. In Table 1, the frame index k is determined by the frame index j in which HARQ feedback is transmitted, and the sub frame index m has the same position as in the previous HARQ subpacket transmission. At this time, the frame offset is generated by the time interval between the transmission time of HARQ feedback and the start time of data retransmission. The time interval is defined as Gap2 and is determined as in Equation 4 below.

Here, N _{CTRL and TTI} are lengths of HARQ feedback transmission intervals according to DL HARQ operation, and F is the number of subframes constituting each frame. In the FDD system, since each link interval is continuous, Gap2 is determined by the UL HARQ feedback transmission interval and the number of subframes in the frame regardless of the subframe index. In general, HARQ feedback has a transmission period of one subframe.

In the DL HARQ, the value of the DL HARQ transmission offset u is determined so that Gap2 of Equation 4 is not smaller than (ie, greater than or equal to) the transmission processing time. For example, u = 0 if Gap2 is not less than the transmission processing time, while u = 1 if Gap 2 is less than the transmission processing time. Here, the u value is adjusted so that the next HARQ data is transmitted in the delayed frame. That is, the u value means an offset value in units of frames, and does not mean a change in the subframe index.

When u thus determined is considered, k is determined as in Equation 5 below.

As described above, when the time required for processing the transmission signal is not secured, the HARQ retransmission time point may be delayed by one frame (that is, u = 1). In the present specification, the term 'sufficient time' refers to a case where the time required for signal transmission processing (transmission processing time) and the time required for signal reception processing (reception processing time) exceed a known reference value. Here, the reference value is initially set or broadcast by the system.

If the frame index j, k is greater than or equal to the total number N of frames constituting one superframe, the superframe index s is increased by 1, and the frame index j, k is expressed by Equation 3 or 5> has the rest of the modulo operation. Referring to Figures 1 and 2 may be considered as N = 4.

Referring to Equation 2 and Equation 4, the DL HARQ feedback offset z and the DL HARQ transmission offset u in FDD are the length of a transmission interval for HARQ operation (burst or feedback), and the system (transmitter and receiver). It can be determined according to the signal processing ability of the. Information about the signal processing capability is predefined or broadcast by the system. As another embodiment, z and u may be broadcast with a predetermined value through system configuration information according to an operation method in the system, instead of being determined as described above.

4 is a diagram illustrating a HARQ operation timing structure for UL data burst transmission in an FDD scheme according to an embodiment of the present invention. Here, assuming that F = 8, N = 4 and Tx / Rx processing time are 3 subframes, respectively, w = 0 and v = 0.

Referring to FIG. 4, when data burst allocation information is transmitted through a DL frequency band in DL subframe 400 of frame i, the transmitter transmits a UL frequency band in UL subframe 410 of frame 5 of i frame. Transmit UL data bursts through In DL subframe 420 of the i + 1 frame, the receiver transmits HARQ feedback based on whether an error of the UL data burst is detected through the DL frequency band. When the HARQ feedback in the DL subframe 420 is NACK, retransmission of the data burst is performed by the transmitting terminal through the UL frequency band in UL subframe 430 of frame i + 1. In this case, when burst allocation information indicating UL burst retransmission is transmitted in the DL subframe 420, burst retransmission is performed according to the allocation indication information.

Referring back to the above operation with reference to Table 2, the frame index j through which the UL data burst is transmitted is determined as (i + floor (ceil (1 + 4) / 8) +0) mod 4 = i, The subframe index m on which the UL data burst is transmitted is determined as {ceil (1 + 4) mod 8} = 5. The frame index k for which HARQ feedback is performed is determined as (j + floor ((5 + 4) / 8) +0) mod 4 = i (j = i) +1, and the subframe index for which HARQ feedback is performed is 1 It is determined as a subframe. If HARQ feedback is NACK, the frame index p at which retransmission of the HARQ data burst is performed is determined as (k + floor (ceil (1 + 4) / 8) +0) mod 4 = i + 1, and the subframe index m is Is determined by 5. Table 2 below shows an embodiment of the UL HARQ operation timing structure of the FDD scheme. The following table is used to determine the transmission time of at least one of an allocation A-MAP IE including data burst allocation information, a HARQ subpacket including a data burst, and a HARQ feedback including an ACK and / or NACK and a HARQ retransmission subpacket. Of course, the present invention is not limited by the following table.

In Table 2, N denotes the number of frames constituting one superframe, and 4 when each superframe consists of four frames, and F means the number of subframes constituting one frame. . I, j, k, and p mean a DL frame index or an UL frame index, l means a DL subframe index for which data burst allocation information is provided, and m indicates an index of a subframe at which data burst transmission starts. Means. In addition, w means UL HARQ feedback offset, and v means UL HARQ transmission offset. Where w and v are in frame units. Therefore, i = 0,1, ..., N-1, j = 0,1, ..., N-1, k = 0,1, ..., N-1, p = 0,1, ..., N-1, l = 0, N _{A -MAP} , ..., N _A-MAP (ceil (F / N _A-MAP ) -1), m = 0,1, ..., F -1, n = 0,1, ..., F-1, w = 0,1, ..., w _max -1, and v = 0,1, ..., v _max -1.

In addition, N _{A - MAP} means a period in which data burst allocation information is provided. When data burst allocation information is provided in every DL subframe, N _{A - MAP} = 1, and when data burst allocation information is provided in two DL subframe intervals, N _{A - MAP} = 2. When N _{A -MAP} = 2, l = 0, 2, ... 2 (ceil (F / 2) -1).

In the UL HARQ transmission / reception of the FDD scheme, the UL data burst allocation information provided in DL subframe of l (lowercase letter L) of frame i indicates transmission of a data burst starting from UL subframe m of frame j. do. If data burst allocation information is provided in every DL subframe (ie, N _{A - MAP} = 1), the data burst allocation information provided in each DL subframe indicates transmission of a data burst starting from nth UL subframes. . That is, m = n. When data burst allocation information is provided for every two DL subframes (ie, N _{A - MAP} = 2), the data burst allocation information provided in subframe l may be the UL subframe n and the UL subframe n + 1. Indicates the transmission of a data burst in a frame. That is, m is one of n or n + 1, and relevance information indicating this is indicated through data burst allocation information. N is defined as n = ceil (l + F / 2) mod F by DL subframe index l through which data burst allocation information is transmitted.

The data burst indicated by the data burst allocation information may be transmitted through one or more subframes, and information on the length N _TTI of the burst transmission interval is indicated by the data burst allocation information.

HARQ feedback for the data burst started in UL subframe m of frame j is transmitted in DL subframe l (lowercase L) in frame k. That is, data burst allocation information and HARQ feedback are transmitted in the same subframe index. Where k is determined by m and j as described in Table 2.

V and w described in Table 2 are UL HARQ transmission offsets and UL HARQ feedback offsets, respectively, and may be calculated using Equations 2 and 4 described above. The UL HARQ transmission offset v is considered for burst transmission or retransmission when data burst allocation information or HARQ feedback is received.

When retransmitting a UL data burst in consideration of asynchronous HARQ, the retransmission time point of the UL data burst is indicated by a transmission position of data burst allocation information and a retransmission indicator included in the data burst allocation information. When retransmitting the UL data burst in consideration of synchronous HARQ, the retransmission of the UL data burst is performed in subframe m of frame p. As described in Table 2, the frame index p is determined by k and l .

The UL HARQ transmission offset v is a time interval in units of frames between when the DL burst allocation information or the DL HARQ feedback is transmitted and when the UL data burst is transmitted, and the transmission interval of the DL data burst (N) is expressed in Equation (2). _{It is} determined in consideration of Gap1 'calculated by applying a transmission interval of data burst allocation information or a transmission interval of HARQ feedback instead of _TTI ). In general, the transmission interval of data burst allocation information or HARQ feedback is one subframe.

In UL HARQ, the value of v is adjusted such that Gap1 'calculated as described above is not smaller than the transmission processing time. For example, if Gap1 'is not less than the transmission processing time, v = 0, whereas if Gap1' is less than the transmission processing time, it is v = 1.

The UL HARQ feedback offset w is a time interval in units of frames between the time when the transmission of the UL data burst and the transmission time of the DL HARQ feedback, and the UL burst transmission instead of the HARQ feedback transmission interval according to the DL HARQ operation in Equation (4). It is determined in consideration of Gap2 'calculated by applying the interval.

In the UL HARQ, the w value is adjusted such that Gap2 'calculated as described above is not smaller than the reception processing time. For example, w = 0 if Gap2 'is not less than the receive processing time, whereas w = 1 if Gap 2' is less than the receive processing time.

As described above, the UL HARQ transmission offset v and the UL HARQ feedback offset w are determined according to the length of the transmission interval for HARQ operation (burst or feedback) and the processing capability of the system (transmitter and receiver). The processing power is predefined or broadcast by the system. As another example, w and v may be broadcast at a predetermined value through system configuration information according to an operation method of the system. In Table 2, if the frame index j, k, p is greater than or equal to N, the superframe index s is increased by 1, and the frame index j, k, p is the modulo operation of Table 2. Has the remainder.

Each frame in TDD communication mode includes DL subframes and UL subframes. In a preferred embodiment of the present invention, a link having a larger number of subframes is divided based on a link having a smaller number of subframes so that DL subframes and UL subframes have a constant correspondence. Each divided region is composed of one or more subframes and has a correspondence with any one subframe in a link having a smaller number of subframes. That is, M subframes are divided into N regions (M> N), and each subframe has a corresponding relationship according to the present invention. Detailed description of the correspondence will be described later.

5 is a diagram illustrating a DL HARQ operation timing structure of a 5: 3 TDD mode according to an embodiment of the present invention. As shown, reference is made to the TDD frame structure of FIG. 2.

Referring to FIG. 5, the transmitter transmits data burst allocation information and DL data burst in DL subframe 500 of frame i, and the receiver transmits HARQ feedback in UL subframe 510 of frame 0 of frame i. Send. Retransmission of the DL data burst according to the HARQ feedback is performed in DL subframe 520 of frame i + 1 by the transmitter. In this case, data burst allocation information indicating transmission of a DL data burst may be transmitted in the first DL subframe 520. HARQ feedback on this is performed in UL subframe 530 of frame i + 1.

In the above description, the DL subframe index and the UL subframe index are defined in each link section. However, the subframe indexes of the DL and UL may be consecutively determined in one frame. In this case, the UL subframe index x is mapped to the subframe index D + x in the frame. Where D represents the length of the DL interval.

The operation will be described again with reference to Table 3 below.

Table 3 below shows an embodiment of a DL HARQ operation timing structure in TDD mode when DL: UL = D: U. Here, D represents the length of the DL interval (the number of subframes), and U represents the length of the UL interval (the number of subframes). The following table is used to determine the transmission time of at least one of an allocation A-MAP IE including data burst allocation information, a HARQ subpacket including a data burst, a HARQ feedback including an ACK and / or a NACK, and a HARQ retransmission subpacket. Of course, the present invention is not limited by the following table.

In Table 3, D denotes the number of DL subframes constituting one DL frame, U denotes the number of UL subframes constituting one UL frame, and N denotes one superframe. It means the number of frames to be 4 when each superframe consists of four frames. The number of subframes constituting one frame is F = D + U and i, j and k are frame indexes, l is a subframe index where data burst allocation information is transmitted, and m is transmission of data bursts. This means the index of the starting subframe, and n means the subframe index on which HARQ feedback is transmitted. Z denotes a DL HARQ feedback offset and u denotes a DL HARQ transmission offset. Therefore, j = 0,1, ..., N-1, k = 0,1, ..., N-1, l = 0, N _A-MAP , ..., N _A-MAP (ceil ( D / N _A-MAP ) -1), m = 0,1, ..., D-1, n = 0,1, ..., U-1, z = 0,1, ..., z _max -1, and u = 0,1, ..., u _max -1.

In addition, N _{A - MAP} means a period in which data burst allocation information is provided. When data burst allocation information is provided in every DL subframe, N _{A - MAP} = 1 and l ranges from 0 to D-1, and N _A when data burst allocation information is provided in two DL subframe intervals. _- a _MAP = 2. When N _{A - MAP} = 2, l = 0, 2, ..., 2 (ceil (F / 2) -1).

The parameter K is a parameter defined by the relationship between D and U, and is defined as, for example, Equation 6 or 7 below. That is, K may be K _c or K _f , depending on the system bandwidth, processing interval, and transmission period (N _{A - MAP} ) of data burst allocation information considered by the system. Where K _c means the value calculated using the ceil () function and K _f means the value calculated using the floor () function. The determination of the K value may vary depending on the system configuration. In general, K _f is used, but K _c can be used when D <U / N _{A - MAP with} F having odd system characteristics.

K _c and K _f have zero or a positive value when D is greater than or equal to U, and a negative value otherwise.

In general, when F is an even number, as f ceil () and floor () perform the same operation, K _f and K _c have the same value. In another embodiment, the value of K may be set as follows. That is, when D <U, K =-ceil (UD) / 2, and when D> = U, K = floor (DU) / 2. That is, regardless of whether F is odd or even, K =-ceil (UD) / 2 when D <U and K = floor (DU) / 2 when D> = U.

In the DL HARQ transmission and reception of TDD mode, i assigned to one DL data burst is provided by the time l DL sub-frame of the frame information indicates the transmission of the data burst, starting from the m times the DL subframe of the i-th frame. When data burst allocation information is provided in every DL subframe (ie, N _{A - MAP} = 1), the data burst allocation information provided in each DL subframe indicates that data burst transmission is started in the corresponding DL subframe. M becomes l . On the other hand, two DL sub-frame if that is each provided with a data burst allocation information (i.e., N _{A -} = _MAP 2), l number of data burst allocation information provided from the sub-frame is the number l DL sub-frame and the l +1 times Indicates transmission of a data burst starting in a DL subframe. That is, m is selected as one of l or l +1, and the relevance information indicating the selection is indicated through data burst allocation information.

The data burst indicated by the data burst allocation information may be transmitted through one or more subframes.

HARQ feedback for the data burst started in DL subframe m of frame i is transmitted in UL subframe n of frame j. N may correspond to one or more DL subframe indexes according to the DL and UL ratio (D: U). If D ≦ U, each UL subframe corresponds to one DL subframe. However, if D> U, each UL subframe corresponds to one or more DL subframes. As defined in Table 3, the subframe index n is determined by K and m, and j is determined by i and z. That is, Table 3 defines a specific correspondence between the DL subframe index and the UL subframe index in one frame according to the DL: UL ratio. In Table 3, the case of D = U is shown to be included in the case of D <= U, but in case of D = U, since K = 0, it has the same result in D <= U and D> U. May be included. In the present specification, the case of D = U is included in the case of D <= U for the DL HARQ timing.

Here, z denotes a DL HARQ feedback offset as described in the FDD DL HARQ timing structure of Table 1, and is used to adjust the frame index on which the HARQ feedback operation is performed to secure sufficient reception processing time as described above. do. In the TDD system, since the DL subframe and the UL subframe are alternately located in time in one frame, Gap3 calculated as in Equation 8 is used to determine the DL HARQ feedback offset z.

Referring to Equation 8, M _DATA is the number of subframes in which the data burst is transmitted, a is the subframe index at which the data burst starts, N _TTI is the length of the transmission interval of the data burst, and b Is a subframe index on which HARQ feedback is transmitted. Therefore, applying Table 3, M _DATA = D, a = m, and b = n.

In DL HARQ in TDD mode, the DL HARQ feedback offset z is adjusted so that the Gap3 calculated through Equation 8 is not less than the reception processing time. For example, z = 0 if Gap3 is not less than the receive processing time, while z = 1 if Gap3 is less than the receive processing time.

When retransmitting a DL data burst in consideration of asynchronous HARQ, the retransmission of the DL data burst is indicated by a retransmission indicator included in the data burst allocation information. When retransmitting a DL data burst in consideration of synchronous HARQ, the retransmission of the DL data burst is performed in subframe m of frame k. In Table 3, the frame index k is determined by the frame indexes j and u through which HARQ feedback is transmitted. Further, the DL burst retransmission is retransmitted according to the content of the allocation information when burst allocation information indicating retransmission of the DL data burst is transmitted.

Here, u represents the DL HARQ transmission offset as described in the FDD DL HARQ timing structure of Table 1, and is determined according to Gap4 calculated as in Equation 9 below. Gap4 represents the time interval between the transmission time of HARQ feedback and the start time of data retransmission in the TDD mode.

Here, M _CTRL is the number of subframes in which HARQ feedback is transmitted, b is a subframe index in which HARQ feedback is transmitted, and a is a subframe index in which retransmission of the data burst starts after HARQ feedback. Therefore, applying Table 3, M _CTRL = U, b = n, a = m.

In DL HARQ in the TDD mode, the DL HARQ transmission offset u is adjusted so that the Gap4 calculated through Equation 9 is not smaller than the transmission processing time. For example, u = 0 if Gap4 is not less than the transmission processing time, while u = 1 if Gap4 is less than the transmission processing time. If u = 1, since the time required for transmission signal processing is not secured, the HARQ retransmission time point is delayed by one frame.

In Table 3, if the frame indexes j and k are greater than or equal to the total number N of frames constituting one superframe, the superframe index s is increased by 1, and the frame index is modulo in Table 3. It has the remainder of the (modulo) operation.

In another embodiment, the DL HARQ feedback offset z and the DL HARQ transmission offset u are mapping relations between data DL subframes and UL subframes, lengths of HARQ operation (burst or feedback) transmission intervals, and / or signal processing capabilities of the system. It can be determined according to.

6 illustrates a HARQ operation timing structure for UL data burst transmission in the TDD mode according to an embodiment of the present invention.

Referring to FIG. 6, when data burst allocation information is transmitted in DL subframe 600 of frame i, the transmitter transmits UL data burst in UL subframe 610 of frame 0. The receiving end transmits HARQ feedback according to whether the UL data burst is successfully received in DL subframe 620 of frame i + 1. Retransmission of the data burst according to the HARQ feedback is performed in UL subframe 630 of frame i + 1 by the transmitter. When burst allocation information indicating retransmission of a UL data burst is transmitted in DL subframe 620, burst retransmission is performed by the burst allocation information.

In the above description, the DL subframe index and the UL subframe index are defined in each link section. However, the subframe indexes of the DL and UL may be consecutively determined in one frame. In this case, the UL subframe index x is mapped to the subframe index D + x in the frame. Where D represents the length of the DL interval.

The operation will be described again with reference to Table 4 below.

Table 4 below shows an embodiment of the UL HARQ operation timing structure in the TDD mode. The following table is used to determine the transmission time of at least one of an allocation A-MAP IE including data burst allocation information, a HARQ subpacket including a data burst, and a HARQ feedback including an ACK and / or NACK and a HARQ retransmission subpacket. Of course, the present invention is not limited by the following table.

In Table 4, D denotes the number of subframes constituting one DL frame, U denotes the number of subframes constituting one UL frame, and K denotes Equation 6 or Math. A parameter defined as in Equation 7>, where N denotes the number of frames constituting one superframe, and is 4 when each superframe consists of 4 frames. I, j, k, and p denote a frame index, l denotes a subframe index in which data burst allocation information is transmitted, m denotes a subframe index in which data burst transmission starts, and K denotes D. Means a parameter defined by the relation between and U. In addition, w means UL HARQ feedback offset, and v means UL HARQ transmission offset. Therefore, i = 0,1, ..., N-1, j = 0,1, ..., N-1, k = 0,1, ..., N-1, p = 0,1, ..., N-1, l = 0, N _{A - MAP} , ..., N _{A - MAP} (ceil (D / N _{A - MAP} ) -1), m = 0,1, ..., U -1, w = 0,1, ..., w _max -1, and v = 0,1, ..., v _max -1.

In addition, N _{A - MAP} means a period in which data burst allocation information is provided. When data burst allocation information is provided in every DL subframe, N _{A - MAP} = 1 and l ranges from 0 to D-1, and N _A when data burst allocation information is provided in two DL subframe intervals. _- a _MAP = 2. When N _{A - MAP} = 2, l = 0, 2, ..., 2 (ceil (D / 2) -1).

In the UL HARQ transmission / reception in the TDD mode, UL data burst allocation information provided in DL subframe # 1 of frame i indicates transmission of data bursts starting from UL subframe m of frame j. Here, m may correspond to one or more DL subframes according to a DL and UL ratio (D: U) and an allocation information period N _{A - MAP} . If ceil (D / N _A-MAP ) ≥U, i.e., the number of DL subframes providing DL control information (data burst allocation information or HARQ feedback) is greater than or equal to the number of UL subframes, Each UL subframe corresponds to one or more DL subframes. However, if ceil (D / N _{A - MAP} ) <U, that is, the number of DL subframes providing DL control information (data burst allocation information or HARQ feedback) is less than the number of UL subframes, each DL sub The frame corresponds to one or more UL subframes.

In addition, when the number of DL subframes to which data burst allocation information is provided is equal to or greater than the number of UL subframes (ceil (D / N _{A - MAP} ) ≥ U), data burst transmission in one UL subframe may be more than one. It may be indicated in the DL subframe. In other words, if l is less than K, the l times DL allocation of data bursts in the sub-frame information, and indicating a data burst transmission from zero, one UL sub-frame, while l is equal to or greater than K is less than U + K The data burst allocation information in DL subframe l indicates data burst transmission starting from subframe llk. If l is equal to or greater than U + K, data burst allocation in DL subframe l is included. The information indicates data burst transmission starting from subframe U-1.

On the other hand, when the number of DL subframes provided with the data burst allocation information is smaller than the number of UL subframes (ceil (D / N _{A - MAP} ) <U), one in the DL subframes provided with the data burst allocation information Data burst transmission in the above UL subframe may be indicated. For example, the data burst allocation information of DL subframe 0 indicates that a data burst is transmitted in UL subframes 0 to ( l -K + N _A-MAP -1), and relevance information about the indication. Is indicated via data burst allocation information.

When the data burst allocation information is provided only through one DL subframe (ceil (D / N _{A - MAP} ) = 1), data burst transmission in all UL subframes is indicated in the corresponding DL subframe. The transmission interval (TTI) of the data burst may be indicated through data burst allocation information, and the frame index j is determined by i and v.

V and w described in Table 4 indicate UL HARQ transmission offsets and UL HARQ feedback offsets as described in the FDD UL HARQ timing structure of Table 2, respectively. The UL HARQ transmission offset v is considered to determine a time point for transmission or retransmission of the data burst after receiving data burst allocation information or HARQ feedback, and as described above, transmission of the data burst to ensure sufficient transmission processing time. Used to adjust the frame index on which the operation is performed.

In UL HARQ in the TDD mode, the UL HARQ transmission offset v substitutes D, which represents the number of DL subframes in which control burst information such as data burst allocation information or HARQ feedback is transmitted to M _CTRL in Equation 9 described above. It is determined according to Gap4 'which is calculated by substituting b for l representing a subframe index in which data burst allocation information or HARQ feedback is transmitted and substituting m for a subframe index in which a data burst is transmitted or retransmitted.

According to a result of comparing the Gap4 'with the transmission processing time required for transmission of the data burst after the HARQ feedback, v = 1 is obtained when the Gap4' is smaller than the transmission processing time, and otherwise v = 0.

In addition, in the UL HARQ mode of the TDD mode, the UL HARQ feedback offset w is a subframe in which a data burst is transmitted to M _DATA in Equation 8 to adjust a transmission time of HARQ feedback after reception of a data burst. It is determined according to Gap3 'calculated by substituting the number U.

According to a result of comparing the Gap3 'with the reception processing time required for transmission of the HARQ feedback after the UL data burst, w = 1 when the Gap3' is smaller than the reception processing time, and w = 0 otherwise.

HARQ feedback for the data burst transmitted in UL subframe m of frame j is performed in DL subframe l of frame k. That is, data burst allocation information and HARQ feedback are transmitted in the same subframe index. Where k is determined by j.

When retransmitting a UL data burst in consideration of asynchronous HARQ, the retransmission time point of the UL data burst is indicated by a retransmission indicator included in data burst allocation information. When retransmitting the UL data burst in consideration of synchronous HARQ, the retransmission of the UL data burst is performed in subframe m of frame p. As described in Table 4, the frame index p is determined by the UL HARQ transmission offset v and the frame index k through which HARQ feedback is transmitted. If the frame index j, k, p is greater than or equal to N, the superframe index s increases by 1, and the frame index j, k, p has the remaining values by the modulo operation of Table 4.

Meanwhile, while the HARQ timing is determined by the formulas of Tables 1 to 4, in the modified embodiment, all possible input values (for example, the number of DL / UL subframes and the subframe index) are determined. It is also possible to determine the HARQ timing by reading a desired result value from the table by having a transmitter and a receiver having a table including the result values according to the equation for the processing time, etc.).

HARQ  Calculation of Feedback / Transmit Offset

Hereinafter, embodiments for obtaining HARQ feedback offset w, z and HARQ transmission offset v, u will be described.

HARQ feedback offset w, z and HARQ transmission offset v, u are mapping relations between DL subframe and UL subframe, length of transmission interval for HARQ operation (burst or feedback) and / or system (transmitter and / or receiver) It can be determined according to the signal processing performance of. In another embodiment, the feedback offsets may be defined by a constant value and broadcast by the system instead of being obtained by the information. Definition of offsets according to the HARQ operation can be summarized as follows.

At least one of the HARQ feedback offset z and the HARQ transmission offset u for the DL HARQ operation according to the FDD mode is calculated by Equation 10 below.

Here, Rx_Time1 represents the reception processing time for the DL data burst and is determined by the reception capability. Tx_Time1 represents the transmission processing time of the DL data burst and is determined by the transmission capability. Rx_Time1 and Tx_Time1 can be collectively referred to as processing time for data bursts. Here, the reception processing of the data burst includes, for example, multiple input multiple output (MIMO) reception processing (Rx processing), demodulation, decoding, and the like. The transmission processing of the data burst includes, for example, encoding, modulation, MIMO transmission processing, and the like. Since DL HARQ, the receiving end is mainly a terminal and the transmitting end considers a base station. In addition, the HARQ feedback transmission interval has considered 1 subframe, and the burst transmission interval is N _TTI .

At least one of the HARQ transmission offset v and the HARQ feedback offset w for the UL HARQ operation according to the FDD mode is calculated by Equation 11 below.

Here, Rx_Time2 represents the reception processing time for the UL data burst and is determined by the reception capability. Tx_Time2 represents the transmission processing time of the UL data burst and is determined by the transmission capability. Rx_Time2 and Tx_Time2 can be collectively referred to as processing time for data bursts. However, since UL HARQ, the receiving end means the base station and the transmitting end means the terminal.

At least one of the HARQ feedback offset z and the HARQ transmission offset u for the DL HARQ operation according to the TDD mode is calculated by Equation 12 below.

Here, Rx_Time3 and Tx_Time3 represent a reception processing time and a transmission processing time for DL data bursts, respectively. Rx_Time3 and Tx_Time3 can be collectively referred to as processing time for data bursts.

At least one of the HARQ transmission offset v and the HARQ feedback offset w for the UL HARQ operation according to the TDD mode is calculated by Equation 13 below.

Here, Rx_Time4 and Tx_Time4 represent reception processing time and transmission processing time for UL data burst, respectively. Rx_Time4 and Tx_Time4 can be collectively referred to as processing time for data bursts.

In consideration of synchronous HARQ, the transmission processing time in UL HARQ operation may be considered differently according to initial transmission or retransmission. That is, in Equations 11 and 13, Tx_Time2 and Tx_Time4 may be replaced with Tx_Time_NewTx and Tx_Time_ReTx depending on whether the transmission is initially performed. Here, Tx_Time_NewTx means transmission processing time for initial transmission and Tx_Time_ReTx means transmission processing time for retransmission. As described above, the initial transmission should encode the burst according to the burst allocation information, but the encoding in the retransmission indicated by NACK may be performed by recycling the burst previously encoded in the initial transmission. Therefore, the HARQ transmission offset can be adjusted by considering the transmission processing time required for initial transmission and retransmission differently.

In addition, according to a retransmission triggering method, a transmission processing time for retransmission may be divided into Tx_Time_ReTx1 and Tx_Time_ReTx2. As a retransmission triggering method, only NACK is indicated or allocation information for NACK and retransmission may be transmitted. Tx_Time_ReTx1 means transmission processing time for retransmission triggered by NACK only, and Tx_Time_ReTx2 means transmission processing time for retransmission triggered by allocation information for retransmission.

Similarly, the UL HARQ transmission offsets in <Table 2>, <Table 4>, <Equation 11>, and <Equation 13> are set to v _new and v _RxTx in consideration of the transmission processing time according to initial transmission or retransmission. Can be adjusted separately. Here, v _new is a UL HARQ transmission offset for initial transmission of the burst considering the transmission processing time of _{Tx_Time_NewTx} , and v _RxTx is a UL HARQ transmission offset for retransmission of the burst considering the transmission processing time of Tx_Time_ReTx.

Legacy ( legacy System support mode

A wireless mobile communication system using the Advanced Air Interface (AAI) of the Institute of Electrical and Electronics Engineers (IEEE) 802.16m has a legacy radio of IEEE 802.16e with a predetermined frame offset within a superframe structure. Can coexist with a mobile communication system. That is, each frame of the 16m mode includes a frame offset to compensate for the difference with respect to the frame of the 16e mode together with the DL subframes and the UL subframes. In this case, the HARQ operation timing structure of the TDD mode follows the HARQ operation timing structures of Tables 3 and 4 corresponding to the DL and UL ratios in the interval in which the network node and the terminal operate in the IEEE 802.16m mode.

The mapping relationship between the DL subframe and the UL subframe is determined according to the DL / UL ratio in the interval in which the network node and the terminal operate in the IEEE 802.16m mode. That is, the subframe index and the number of transmission intervals for HARQ operation are determined according to the DL / UL ratio. However, since the IEEE 802.16e mode and the IEEE 802.16m mode coexist in one frame, the frame index is determined based on the total DL / UL ratio in the TDD system, not the DL / UL ratio in the section operating in the 16m mode. All.

Herein, the number of subframes of each link interval in the TDD system is referred to as D 'and U', and the index of the subframe according to the DL / UL ratio D ': U' in the TDD system is determined. l ' , m', and n '. In the 16m mode, the number of subframes in each link interval is referred to as D and U, and the index of the subframe according to D: U, which is a DL / UL ratio, in the interval operating in the 16m mode. l ' , m, n.

HARQ operation timing in the 16m mode, except for the legacy section operating in the 16e mode is shown in Tables 3 and 4 using subframe indexes aligned within D: U. It has a defined timing structure. However, the frame indices i, j, and k, which are determined according to the HARQ feedback offset (z or w) and the HARQ transmission offset (u or v), are subframe indexes l ' , m', n 'within D': U '. Use

7 is a diagram illustrating a HARQ operation timing structure according to DL data burst transmission in a 5: 3 TDD mode in a mode where two systems coexist according to an embodiment of the present invention. As shown in FIG. 7, two DL subframes and a UL FDM region are dedicated for a mode supporting a legacy system (that is, a legacy supporting mode) and used as a legacy mode. The subframe indexes are renumbered in intervals except intervals. That is, in the entire TDD system, a DL frame is composed of DL subframes 0 to 4, and DL subframes 2 to 4 each have rearranged DL subframe indexes 0, 1, and 2 in a region operating in 16m mode. . And since UL coexists with FDM, the 16m operation mode occupies the entire UL interval. Therefore, the frame operating in the 16m mode consists of three DL subframes and three UL subframes.

Referring to FIG. 7, since D = 3 and U = 3, K = 0. While D 'is 5 and U' is 3. In the transmission of the TDD DL HARQ data burst, data burst allocation information and data burst are transmitted in DL subframe 0 of frame i, and HARQ feedback thereof is transmitted in UL subframe 0 of frame i. Retransmission of the HARQ data burst is performed in DL subframe 0 of frame i + 1. Feedback on this is performed in DL subframe 0 of frame i + 1. In this case, the transmission / reception processing time was considered as 2 subframes, respectively.

8 is a diagram illustrating a HARQ operation timing structure according to UL data burst transmission in a TDD mode in a mode where two systems coexist according to an embodiment of the present invention.

Referring to FIG. 8, since D = 3 and U = 3 according to the same frame structure as in FIG. 7, K = 0. In the transmission of the TDD UL HARQ data burst, data burst allocation information is transmitted in DL subframe 0 of frame i, and the UL data burst is transmitted in UL subframe 0 of frame i. HARQ feedback is performed in DL subframe 0 of frame i + 1, and retransmission of the HARQ data burst is performed in UL subframe 0 of frame i + 1. In this case, data burst allocation information indicating transmission of a UL data burst may be transmitted in the DL subframe. In this case, the transmission / reception processing time was considered as 2 subframes, respectively.

Meanwhile, resources used in the IEEE 802.16e wireless mobile communication system exist in the frame offset period shown in FIGS. 7 and 8.

The HARQ operation timing structure proposed in Tables 1 to 4 is determined according to the subframe index where the burst allocation information is transmitted or the subframe index which starts the data burst regardless of the length of the data burst transmission interval. . Therefore, when synchronous HARQ is used, HARQ feedback is periodically transmitted only in a specific subframe, so that a receiving end can save power for monitoring reception of HARQ feedback and efficiently support co-located coexistence (CLC).

Long transmission interval ( long TTI )

As another embodiment of the present invention, when the data burst is transmitted over two or more subframes, that is, the HARQ timing described in Tables 1 to 4 mentioned above in HARQ timing according to a long TTI. In order to support faster ACK timing than the structure, HARQ feedback timing may be determined according to the subframe index where the transmission of the data burst ends instead of the subframe index where the transmission of the data burst begins. This determination method may be used for fast ACK timing mainly in the asynchronous HARQ method.

In Table 1, the timing of the HARQ feedback is adjusted as follows. That is, indices of UL subframes and frames in which HARQ feedback is transmitted according to m '(= m + N _{TTI -} 1), which is the last subframe index of the data burst transmission interval, instead of m, the first subframe index of the data burst transmission interval, Is determined.

9 is a diagram illustrating a HARQ operation timing structure for DL data burst transmission in an FDD scheme according to another embodiment of the present invention. Here, it is assumed that N _TTI = 4, F = 8, and N _{A - MAP} = 1, and transmission / reception processing time is 3 subframes or less, respectively, DL HARQ feedback offset z and DL HARQ transmission offset u are each 0.

Referring to FIG. 9, the data burst allocation information provided in DL subframe 1 of frame i may include DL data bursts in a burst transmission interval 900 from DL subframe 1 to DL subframe 4 of frame i. Indicates that is transmitted. HARQ feedback for the DL data burst is UL subframe 910 of frame (i + 1) corresponding to DL subframe 4 of frame i according to the subframe index where the transmission of the data burst ends. Is sent from. That is, n = 0 (= ceil (1 + 4-1 + 4) mod 8) and j = i + 1 (= (i + floor (ceil (1 + 4-1 + 4) / 8) mod 4) ))to be. In the case of synchronous HARQ, data burst transmission 920 after HARQ feedback is started in DL subframe 1 of frame i + 2, which is the same subframe position as before.

As described above, in determining the HARQ feedback timing in Tables 1 to 2, instead of the subframe index m at which transmission of the data burst starts, the last subframe of at least one subframe in which the data burst is transmitted. HARQ feedback timing may be determined using m ', which is an index of.

Similarly in the DL HARQ operation timing structure of the TDD mode, for faster ACK timing, instead of m, which is a subframe index at which data burst transmission starts, m '(= m + N _TTI , which is a subframe index at which data burst transmission ends). _- 1) for the HARQ feedback it may be determined by applying a timing in <Table 3> mentioned above.

FIG. 10 illustrates a HARQ operation timing structure for DL data burst transmission in a TDD mode according to another embodiment of the present invention. Here, N _TTI = 4, D = 4, U = 4, the transmission and reception processing time is 3 subframes, respectively, K = 0, z = 0.

Referring to FIG. 10, the data burst allocation information provided in DL subframe 0 of frame i may include a DL data burst in a burst transmission interval 1000 from DL subframe 0 to DL subframe 3 of frame i. Indicates that is transmitted. HARQ feedback for the DL data burst is transmitted in UL subframe 1010 of frame i corresponding to DL subframe 3 of frame i, according to Table 3. That is, n = 3 (= 3-0) and j = i (= (i + 0) mod 4). In case of synchronous HARQ, if data retransmission after HARQ feedback is required, data burst retransmission 1020 starts at DL subframe 0 of frame i + 2, which is the same subframe position as before.

However, in a HARQ timing structure for long TTI transmission in a TDD system, a method of providing fast HARQ feedback timing according to a DL: UL ratio and transmission / reception processing time is different. As an example, HARQ feedback timing for a long TTI (5 subframes) for DL HARQ in a 5: 3 TDD mode will be described when a transmission / reception process time is 3 subframes and a TTI is an entire period of a corresponding link.

When the HARQ feedback timing is provided according to the transmission start time of the data burst, the HARQ feedback is provided in the UL subframe 0 of the next frame corresponding to the DL subframe 0 where the transmission of the data burst starts. On the other hand, when the HARQ feedback timing is provided according to the transmission end time of the data burst, the HAQR feedback is provided in the UL subframe 3 of the next frame corresponding to the DL subframe 4 where the transmission of the data burst ends. As such, when a long TTI is used in a DL HARQ in a 5: 3 TDD mode, using a data burst transmission start time provides faster HARQ feedback timing for a longer TTI than using a data burst transmission end time. .

As another example, feedback timing for a long TTI (4 subframes) for DL HARQ in the 4: 4 TDD mode is described.

When the HARQ feedback timing is provided according to the transmission start time of the data burst, the HARQ feedback is provided in the UL subframe 0 of the next frame corresponding to the DL subframe 0 where the transmission of the data burst starts. On the other hand, when the HARQ feedback timing is provided according to the transmission end time of the data burst, the HARQ feedback is provided in the UL subframe 3 of the same frame corresponding to the DL subframe 3 where the transmission of the data burst ends. As such, in the 4: 4 DL mode HARQ, unlike in the 5: 3 DL mode, using a data burst transmission end point provides fast HARQ feedback timing for a TTI longer than using a data burst transmission start point. do.

Therefore, in the embodiment of the present invention, the appropriate HARQ operation timing structure is selected according to the DL / UL ratio and the transmission / reception processing time. Specifically, in determining the HARQ feedback timing in Tables 1 to 4, instead of the subframe index m at which the data burst starts, the index of the last subframe among the at least one subframe in which the data burst is transmitted. m '(= m + N _TTI- 1) may be used. The information on the HARQ operation timing structure may be provided through, for example, a DL common control channel as system information.

HARQ  Change in Feedback / Transmit Offset

Hereinafter, other embodiments of the DL and UL HARQ operation timing structure of the TDD mode proposed by the present invention will be described. In detail, changes in the HARQ feedback offset and the HARQ transmission offset according to the subframe position where DL or UL transmission is performed will be described.

11A and 11B show a HARQ operation timing structure for N _{A - MAP} = 1 when D + U = 8.

FIG. 11A illustrates a HARQ operation timing structure when D: U = 5: 3 and a burst transmission interval is 1 subframe. Referring to FIG. 11A, when the transmission / reception processing time is 2 subframes, HARQ feedback / transmission offset = 0. That is, since the processing for the transmission of each DL subframe can be completed in two subframes (that is, since Gap3 and Gap4 are greater than 2), the corresponding UL transmission is performed without delay in the following UL interval. Similarly, since processing for transmission of each UL subframe is completed in two subframes (that is, since Gap3 and Gap4 are greater than 2), corresponding DL transmission is performed without delay in the subsequent DL period.

On the other hand, when the transmission and reception processing time is three subframes, respectively, the HARQ UL transmission timing associated with the fourth DL subframe is delayed by one frame period. It takes 3 subframes to process the transmission of DL subframe 4, but it is difficult to perform UL transmission in 2 subframes (= 5-4-1 + 2), which is an interval to the corresponding UL 2 subframe. Because. Therefore, the UL transmission in the second UL subframe corresponding to the fourth DL subframe is delayed by one frame, that is, the second UL subframe of the next i + 1 frame.

FIG. 11B illustrates a HARQ operation timing structure for a case where D: U = 3: 5 and a burst transmission interval is 1 subframe. Referring to FIG. 11B, when the transmission / reception processing time is 2 subframes, HARQ feedback / transmission offset = 0. On the other hand, when the transmission and reception processing time is 3 subframes, respectively, since Gap = 3-0-1-0 = 2, the UL transmission timing in the UL subframe 0 associated with the DL subframe 0 is delayed by one frame period. Since, Gap = 5-4-1 + 2 = 2, the DL transmission timing in DL subframe 2 associated with UL subframe 4 is delayed by one frame period. This is because each gap is less than the transmit or receive processing time.

12 shows a HARQ operation timing structure for D + U = 7.

FIG. 12 (a) illustrates a HARQ operation timing structure when D: U = 4: 3, N _{A - MAP} = 1, and a burst transmission interval is 1 subframe. Referring to FIG. 12A, when the transmission / reception processing time is 2 subframes, HARQ feedback / transmission offset = 0. On the other hand, when the transmission and reception processing time is 3 subframes, respectively, since Gap = 4-3-1 + 2 = 2, the HARQ UL transmission timing in the UL subframe 2 associated with the DL subframe 3 is delayed by one frame period. do.

FIG. 12 (b) shows a HARQ operation timing structure for a case where D: U = 3: 4, N _{A - MAP} = 1 and a burst transmission interval is 1 subframe. In this case, since D + U is odd and D <U, K _c (= -1) according to ceil () is used. Referring to FIG. 12B, when the transmission and reception processing time is 2 subframes, respectively, HARQ feedback / transmission offset = 0. On the other hand, if the transmission and reception processing time is 3 subframes, respectively, HARQ UL transmission timing is delayed by one frame period in UL subframe 0 associated with DL subframe 0.

FIG. 13 shows a HARQ operation timing structure for N _{A - MAP} = 1 when D + U = 6.

FIG. 13 (a) illustrates a HARQ operation timing structure for a case where D: U = 4: 2 and a burst transmission interval is 1 subframe. Referring to FIG. 13A, when the transmission / reception processing time is 2 subframes, respectively, HARQ UL transmission timing associated with DL subframe 3 is delayed by one frame period. In addition, when the transmission and reception processing time is three subframes, respectively, HARQ DL transmission timing associated with UL subframe 0 is delayed by one frame period, and HARQ UL and DL after associated with DL subframes 1 and 2 Each transmission timing is delayed by one frame period. In addition, HARQ UL transmission timing associated with DL subframe 3 is delayed by one frame period.

FIG. 13 (b) shows a HARQ operation timing structure for one subframe with D: U = 3: 3 and a burst transmission interval. Referring to FIG. 13B, when the transmission / reception processing time is 2 subframes, respectively, HARQ feedback / transmission offset = 0. When the transmission / reception processing time is 3 subframes, respectively, the HARQ feedback / transmission offsets are all delayed by 1, that is, by one frame period.

Relay structure

Hereinafter, a HARQ operation timing structure in a wireless mobile communication system supporting a relay structure according to a preferred embodiment of the present invention will be described.

In case of supporting the relay structure, the base station and the terminal communicate directly or at least one relay station (RS), and the relays between the base station and the terminal are odd-hop RS or even-hop. It is classified as a relay station (Even-Hop RS). Each relay station includes a controller for determining when to perform HARQ transmission according to a frame structure and HARQ operation timing to be described later, and at least one of transmitting and receiving data burst allocation information, data burst, and HARQ feedback at timing according to the control of the controller. It is configured to include a transceiver. Here, data transmission is equally applied to data transmission between the base station and the relay station or data transmission between the relay station and the terminal.

In the present specification, an HARQ operation timing structure of a section in which a relay station and a terminal operate in a 16m mode will be described as an embodiment.

14 illustrates a frame structure of a wireless mobile communication system supporting a relay structure according to a preferred embodiment of the present invention.

Referring to FIG. 14, a frame 1410 of a base station includes a DL access area 1412 transmitted directly from a base station to a terminal, a DL transmission area 1414 transmitted from a base station to a terminal or a relay station, and a network coded reception area (Network). Coding Receive Zone 1416, a UL access area 1418 received from a terminal, and a UL reception area 1420 received from a terminal or relay station. A gap (Gap) 1422 exists between the transmission areas 412 and 1414 and the reception areas 1416, 1418 and 1420 for switching between transmission and reception. In FIG. 14, the frame structure is one example, and one frame includes at least one of the aforementioned DL access area, DL transmission area, network coded reception area, UL access area, and UL reception area.

The frame 1420 of an odd-hop relay station includes a DL access area 1432 transmitted to a terminal, a DL transmission area 1434 transmitted to a terminal or an even-hop relay station, and a DL reception area received from an even-hop relay station or a base station. 1444, a network coded transmission region 1438, a UL reception region 1440 received from a terminal or even-hop relay station, and an UL transmission region 1442 transmitted to an even-hop relay station or base station. There is an interval 1444, 1446, and 1448 for transmission / reception switching between the transmission areas 1432, 1434, 1438, and 1442 and the reception areas 1434 and 1440.

The frame 1450 of an even-hop relay station includes a DL access area 1452 transmitted to a terminal, a DL reception area 1454 received from an odd-hop relay station, and an DL transmission area 1456 transmitted to an odd-hop relay station or a terminal. And a network coded reception area 1458, an UL transmission area 1460 transmitted to an odd-hop relay station, and an UL reception area 1462 received from a terminal or odd-hop relay station. There is an interval 1464, 1466, 1468, and 1470 for transmitting / receiving switching between the transmission areas 1452, 1456, and 1460 and the reception areas 1454, 1458, and 1462.

As described above, the HARQ operation timing structure in the region in which at least one relay station communicates with the terminal is similar to the HARQ operation in the mode supporting the legacy system described above. The mapping relationship is determined according to the DL: UL ratio in the area communicating with the UE in the frame of the RS, and the frame index is determined according to the subframe index determined based on the DL: UL ratio.

15A and 15B illustrate an example of a RS frame structure in a TDD mode according to an embodiment of the present invention. Here, a TDD frame structure with D ': U' = 4: 4 is illustrated, and a network coded transmission / reception area is omitted.

Referring to FIG. 15A, DL subframes 0 to 2 in frame i used by an odd-hop relay station are used for DL transmission, that is, for transmission from a relay station to a terminal or a lower relay station, and the other DL subframe is used. DL reception, i.e. reception from a base station. In addition, UL subframes 0 and 1 are used for UL reception, i.e., reception from the UE, and the remaining two UL subframes are used for UL transmission, i.e., transmission to an upper relay station or a base station.

Referring to FIG. 15B, in subframe i used by an even-hop relay station, subframes 0 and 1 positioned at the beginning of a DL interval are used for DL transmission, that is, for transmission from a relay station to a terminal. Two DL subframes located at are used for DL reception, i.e., reception from an upper odd-hop relay station. In addition, UL subframes 0 and 1 located at the end of the UL interval are used for UL reception, that is, reception from the UE, and two UL subframes located in front are used for UL transmission, that is, for transmission to an upper odd-hop relay station. do.

16A and 16B illustrate an HARQ operation timing structure for an odd-hop relay station according to an embodiment of the present invention. Where D: U = 3: 2.

FIG. 16A illustrates a HARQ operation timing structure in which K = 0 and _Kf in consideration of a floor operation. As illustrated, HARQ UL transmission timing corresponding to DL subframe 2 is delayed by one frame period. FIG. 16B illustrates a HARQ operation timing structure in which K = 1 using ceil operation and considering K _c , and as shown, HARQ UL transmission timing corresponding to DL subframes 1 and 2 is one frame period. Delay.

17 illustrates an HARQ operation timing structure for an even-hop relay station according to an embodiment of the present invention. Where D: U = 2: 2. As illustrated, the HARQ DL transmission timing corresponding to the UL subframe 0 is delayed by one frame period.

As described above, a value of K that can provide faster HARQ timing needs to be selected according to the DL / UL ratio and the transmission / reception processing time. The system operator can select an appropriate HARQ operation timing structure and a value of K according to system configuration information such as a DL / UL ratio and a transmission / reception processing time that the system operates. The system configuration information is provided through a DL common control channel. .

Long transmission interval ( long TTI For) HARQ  Timing structure

In the following, HARQ timing structure according to allocation information for long TTI transmission will be described with reference to Tables 3 and 4.

In DL HARQ, when allocation information indicating transmission of a data burst having a long TTI is transmitted in a certain DL subframe, the long TTI transmission indicated by the allocation information is the first DL subframe of the next frame (DL subframe # 0). ), And the feedback thereof is then transmitted in a UL subframe corresponding to the DL subframe (the subframe indicated by the burst allocation information) of the frame. And when long TTI transmission indicated by allocation information provided in a certain DL subframe in UL HARQ is not possible in the same frame, the UL data burst is transmitted in the first UL subframe (UL subframe 0) of the next frame, Feedback thereto is then transmitted in a DL subframe having the same index as the DL subframe (the subframe indicated by the burst allocation information) of the frame. The frame index is determined by the above-described HARQ transmission offset and HARQ feedback offset. Detailed description thereof is as follows. For example, if a DL long TTI occupies the entire DL interval (N _TTI = D), the burst transmission should begin in DL subframe 0. However, if burst allocation information is later than the start of transmission, i.e., when burst allocation information transmitted in a DL subframe where l is non-zero indicates DL long TTI transmission, data bursts will not be transmitted in the same frame. Long TTI transmission is considered to be indicated at.

For DL HARQ, referring to Table 3, allocation information transmitted in DL subframe l (lowercase L) of frame i is N _{A - MAP.} According to the burst transmission in DL subframe m. However, in the case of long TTI transmission, the transmission start position of the data burst is determined by the DL subframe index m and the transmission interval N _TTI . Therefore, the long TTI transmission starts in DL subframe h of frame a and the corresponding HARQ feedback is transmitted in UL subframe f of frame b. If the UL HARQ feedback is NACK, retransmission is performed in DL subframe h or subsequent DL subframes of frame c. Here, frame indexes a, b, c and subframe indexes h, f are indexes i, l and m obtained from allocation information, corresponding UL subframe index n, and transmission interval N _TTI . Is determined as follows.

That is, the long TTI transmission indicated by the allocation information starts at subframe m of frame i when Dm≥N _TTI , so a = i and h = m. On the other hand, if the Dm <N _TTI, long TTI transmission from 0 sub-frame of m times DL sub because the remaining period of the subsequent frame may be a burst of N _TTI length of transport is smaller than N _TTI next frame (i + 1) is Where a = i + 1 and h = 0.

The UL subframe index f through which the UL HARQ feedback is transmitted for the transmitted burst is determined by the DL subframe index l through which allocation information is transmitted so that UL HARQ feedback is not driven in a specific UL subframe. The relationship between l and f follows the relationship between m and n defined in <Table 3>. Therefore, since UL HARQ feedback is transmitted in the next frame, b = a + 1 (= i + 2).

i번 프레임의 2번 DL 서브프레임에서 전송되는 할당 정보(즉 l=2)에 대한 긴 TTI 전송은, 5(=D) - 2(=m) < 5(=N_TTI)이므로, i+1 (=a)번 프레임의 0 (=h)번 DL 서브프레임에서 시작되고, 이에 대한 UL HARQ 피드백은 i+2 (=b)번 프레임의 1 (2-1=n)번 UL 서브프레임에서 전송된다. For example, when N _TTI = 5, N _{A - MAP} = 1, K = 1, and Tx / Rx Processing time = 3 in a 5: 3 TDD structure,

Long TTI transmission for allocation information (i.e. l = 2) transmitted in DL subframe 2 of frame i is i + 1 since 5 (= D)-2 (= m) <5 (= N _TTI ). starts at DL subframe 0 (= h) of frame (= a), and UL HARQ feedback for this is performed in frame i + 2 (= b). It is transmitted in one (2-1 = n) UL subframes.

As another example, when a long TTI period occupies the entire downlink period in the TDD DL, burst transmission always starts in DL subframe 0. In this system, when data burst allocation information transmitted in DL subframe l indicates long TTI transmission of DL, if l = 0, subframe index m, n and frame index j for HARQ operation are shown in Table 3. Is calculated as On the other hand, if l ? 0, the data burst corresponding to the data burst allocation information indicates a burst transmission starting from frame 0 of frame (i + 1), which is the next frame, not frame i. (M = 0) The feedback for the data burst is transmitted in subframe n of frame j, where n and j are determined according to Equation 14 below instead of Table 3. That is, the position ( n , j ) where the HARQ feedback is transmitted is determined using the DL subframe index ( l ) provided with the data burst allocation information and the frame index ( i + 1) through which the data burst is transmitted.

Since m = 0 and N _TTI = D, z is calculated as shown in Equation 15 by substituting Equation 12 mentioned above. N is determined by the DL subframe index l through which data burst allocation information is transmitted.

For UL HARQ, referring to Table 4, allocation information transmitted in DL subframe l of frame i is performed in UL subframe m of frame j according to N _{A - MAP} and DL subframe index l . Indicate the starting burst transmission. In the case of long TTI transmission, the transmission start position of the data burst is determined by the UL subframe index m and the transmission interval N _TTI . Therefore, the long TTI transmission starts at UL subframe h of frame a and the corresponding HARQ feedback is transmitted at DL subframe f of frame b. If the DL HARQ feedback is NACK, retransmission is performed in UL subframe h of frame c. Here, frame indexes a, b, c and subframe indexes h and f are indexes (i, l ) through which allocation information is transmitted, corresponding UL frame and subframe indexes (j, m), and transmission interval (N _TTI ). Is determined as follows.

That is, the long TTI transmission indicated by the allocation information becomes j = i when Um ≥ N _TTI and starts at subframe m of frame j, so a = i and h = m, whereas Um <N _TTI , is the j = i + 1 is longer TTI transmitted in 0 the UL subframe of the next frame (i + 1) because the remaining period of the subsequent m number UL sub-frame may be a burst of N _TTI length of transport is smaller than N _TTI Since a = i + 1 and h = 0. And DL HARQ feedback is therefore provided in one DL subframe index l = f l. Referring to Equation 13, if UhN _TTI + l ≥ Rx_Time4, DL HARQ feedback is provided in frame b = a + 1. If UhN _TTI + l <Rx_Time4, DL HARQ feedback is provided in frame b = a + 2. Is provided. If the DL HARQ feedback is NACK, the retransmission begins at UL subframe h in frame c, where similar to calculating frame index a, c = b if a = i, c for a = i + 1. = b + 1.

For example, in a 5: 3 TDD structure, when N _TTI = 3, N _{A - MAP} = 1, and Tx / Rx Processing time = 3, it is transmitted in DL subframe 2 of frame i. The UL burst transmission for the allocation information starts at UL subframe 0 (= h) of frame i + 1 (= a), since 3 (= U)-1 (= m) <3 (= N _TTI ). DL HARQ feedback for this is 3 (= U)-0 (= h)-3 (= N _TTI ) + 2 (= l) <3 (= Rx_Time), so frame i + 2 (= b) Is transmitted in 2 (= f) times of UL subframe. If the DL HARQ feedback is NACK, since the HARQ transmission offset is 1, as recalculated as a = i + 1, retransmission is transmitted in UL subframe 0 of frame i + 3 (= b + 1).

As another example, when a long TTI period occupies the entire uplink period in TDD UL, burst transmission always starts in subframe 0. In such a system, when data burst allocation information transmitted in DL subframe l indicates long TTI transmission of UL, the data burst corresponding to l starts transmission in frame 0 of frame j, where (m = 0 The feedback for the data burst is transmitted in DL subframe l of frame k. If the HARQ feedback is NACK, HARQ retransmission starts in UL subframe 0 of the frame p. Here, the frame index j, k, p is calculated using the equation defined in Table 4 using the HARQ transmission offset v and the HARQ feedback offset w in consideration of m = 0.

In the FDD mode, the DL subframe and the UL subframe are provided continuously in different frequency bands, so that a long TTI transmission can start in any subframe. However, when a long TTI start position is limited to a specific subframe in consideration of implementation complexity, control information (eg, resource allocation information and HARQ feedback information) may be concentrated in a corresponding subframe as in the TDD mode. Therefore, similarly to the TDD mode, the HARQ timing needs to be readjusted.

The following HARQ timing may be considered when the long TTI transmission for the FDD system DL HARQ operation is limited to start at subframe x, which is a specific DL subframe. Long TTI transmissions include one or more DL subframes (x ₁ , x ₂ , ... x _max ). Consider N _{A - MAP} = 1 here. That is, when data burst allocation information transmitted in a DL subframe other than l ≠ x indicates a long TTI, the corresponding long TTI transmission starts in a DL subframe capable of long TTI transmission after subframe l .

In this case, when the data burst allocation information transmitted in DL subframe l indicates long TTI transmission of the DL, if l = x, the subframe indexes m and n and the frame index j for HARQ operation are shown in Table 1 below. Is calculated as On the other hand, if l ≠ x, transmission of the data burst corresponding to the data burst allocation information starts in frame m. Feedback for the data burst is transmitted in subframe n of frame j, where m , n and j are determined according to Equation 16 below instead of Table 1. That is, the position ( n , j ) where the HARQ feedback is transmitted is determined using the DL subframe index ( l ) provided with the data burst allocation information, the subframe index #x and the frame index where the burst is transmitted.

Here, x _n ⁱ represents the x _n th subframe of the i th frame, where l = 0, 1, ..., F-1.

For example, consider the example where the start of a long TTI transmission is limited to DL subframes 0 and 4, and F = 8, N _TTI = 4, and transmission and reception processing times are 3 subframes. The long TTI transmission indicated by the data burst allocation information provided in any one of subframes 1 to 3 of the frame i (i.e., x ₂ = 4) may be applied to the DL subframe 4 of the frame i (m = 4). ), And the corresponding HARQ feedback is transmitted in n UL subframes (where n is 5 to 7) of frame i + 1. Where (ceil (8/2) -4 + 3) is not less than 3, so z = 0. In addition, the long TTI transmission indicated by data burst allocation information provided in DL subframes 5 to 7 of frame i starts at DL subframe 0 (m = 0) of frame i + 1 and corresponds to HARQ feedback is transmitted in subframe n (n is 1 to 3) of frame i + 2. Where (ceil (8/2) -4-5) is less than 3, so z = 1.

When long TTI transmission is limited to start at subframe y, which is a specific UL subframe, for the UL HARQ operation in FDD mode, the following HARQ timing may be considered as described above. The long TTI transmission includes one or more UL subframes (y ₁ , y ₂ , ... y _max ).

In the above case, when data burst allocation information transmitted in DL subframe l indicates long TTI transmission of UL, when n is equal to y, the subframe index m and the frame index j where HARQ burst transmission is performed are It is calculated as shown in Table 2. On the other hand, if n ≠ y, UL data burst transmission corresponding to the data burst allocation information is performed in UL subframe m. That is, transmission of data bursts is indicated in UL subframe m of frame j. HARQ feedback for the data burst is transmitted in DL subframe l of frame k. And if HARQ feedback is NACK or resource allocation for retransmission is indicated, HARQ retransmission is started in subframe m of frame p. Where m, j, k, and p are determined according to Equation 17 instead of Table 2. That is, the location (m, j ) to which the HARQ subburst is transmitted is transmitted using a DL subframe index ( l ) provided with data burst allocation information, a subframe index (y) and a frame index (i) at which the burst is transmitted. Is determined.

Here, the frame index j, k, p is calculated using the equation defined in Table 2 using the HARQ transmission offset v and the HARQ feedback offset w in consideration of m = 0.

Here, y _n ⁱ represents the subframe y _{n of the} frame i, l = 0, 1, ..., F-1.

For example, the start of a long TTI transmission is limited to UL subframes 0 and 4 (ie y ₁ = 0, y ₁ = 4), and F = 8, N _TTI = 4, and the transmit and receive processing times are Considering the example that is 3 subframes. The long TTI transmission indicated by the resource allocation information provided in any one of subframes 1 to 3 of the frame i (i.e., 1 ≦ l ≦ 3 and 5 ≦ n ≦ 7) is determined by the i + 1 frame. Starting from UL subframe 0 (m = 0), the corresponding HARQ feedback is transmitted in any one of subframes 1 to 3 of frame i + 2. Here, v = 1 because (ceil (8/2) -1 + 0-n) is less than 3, and w = 0 since (floor (8/2) -4 + n-0) is not less than 3. In addition, the long TTI transmission time frame i of 5 to 7 of any one DL subframe of the time, the data burst allocation information provided from the (so that is, 5≤ l ≤7, 1≤n≤3) instructions, i + 1 Starting from the 4th UL subframe (m = 4) of frame 1, the corresponding HARQ feedback is transmitted in subframe 1 (l is 5 to 7) of frame i + 2. When HARQ feedback is NACK or resource allocation for retransmission is indicated, HARQ retransmission is started in UL subframe 4 of frame i + 3. Where v = 0 since (ceil (8/2) -1 + 4-n) is not less than 3, and w = 1 since (floor (8/2) -4 + n-4) is less than 3.

As another embodiment, when data burst allocation information is transmitted in all DL subframes, the allocation information transmission period N _{A - MAP} = 1 becomes <Table 1> to <Table 4> are the following <Table 5> to <Table 8>. The following table is used to determine the transmission time of at least one of an allocation A-MAP IE including data burst allocation information, a HARQ subpacket including a data burst, and a HARQ feedback including an ACK and / or NACK and a HARQ retransmission subpacket. Of course, the present invention is not limited by the following table.

As an example, when each superframe consists of four frames, as shown in FIG. Also, when D and U are the same in “HARQ feedback in UL” in <Table 7> and “HARQ Subpacket Tx in UL” in <Table 8>, the value of n is the same no matter which formula is used. That is, n = m-k.

In another embodiment, HARQ timing is provided by having a transmitter and receiver having a table including the result values according to the formulas of Tables 4 to 8 for all possible input values, and reading the desired result values from the table. Of course it is also possible to determine.

As another embodiment, the above FDD DL HARQ timing, FDD UL HARQ timing, TDD DL HARQ timing, TDD UL HARQ timing in the case of the default TTI and long TTI can be summarized as follows. Same as

In another embodiment, a HARQ timing is provided by having a transmitter and receiver having a table including the result values according to the formulas of Tables 9 to 12 for all possible input values, and reading a desired result value from the table. Of course it is also possible to determine.

As another embodiment, the above-described UL HARQ operation timing may be applied to a channel having a relationship between resource allocation and corresponding UL transmission. For example, in the case of the UL fast feedback channel, the base station transmits resource allocation information for UL fast feedback in the l- th subframe of the i-th frame, and UL fast feedback information corresponding to the resource allocation information is The timing of transmission, ie the frame index and subframe index, is determined by using i and l . As a specific example, the frame index j and the subframe index m through which the UL fast feedback information is transmitted are determined by any one of Tables 2, 4, 6, and 8 mentioned above. .

In the present specification, in the description of the TDD system, the DL subframe index and the UL subframe index are defined in each link period. However, the subframe indexes of the DL and UL include one DL and an UL period. It can be determined continuously within the frame. In this case, the UL subframe index x is mapped to the subframe index D + x in the frame.

18 and 19 show an operation flowchart between a base station and a terminal for a DL and UL HARQ timing structure according to a preferred embodiment of the present invention, respectively.

Referring to FIG. 18, in step 1802, system configuration information is transmitted from the base station BS to the terminal MS. The system configuration information is broadcast from the base station or obtained through negotiation between the base station and the terminal to enable system access of the terminal. Specifically, the system configuration information is information required for operating the HARQ timing structure, and includes bandwidth (total number of subframes), number of subframes (D and U) of each link, transmission / reception processing time of a base station, transmission / reception processing time of a terminal, and the like. It includes.

After the terminal acquires the system information through the system configuration information and accesses the base station, in step 1804, the base station and the terminal may perform data communication. As described above, if the terminal knows the system configuration information in advance, step 1804 may be omitted.

In step 1806, allocation information including or indicating a frame index, a subframe index, a long TTI length, and MAP relevance for the HARQ operation timing is transmitted from the base station to the terminal. (DL subframe 1 of frame i) The terminal decodes the allocation information to extract necessary information, and in particular, a frame index on which a previous HARQ operation is performed according to at least one of the above-described embodiments of the present invention. And the subframe index.

In step 1808, the base station transmits a DL HARQ burst in subframe h of frame a according to the allocation information, and the terminal decodes the DL HARQ burst according to the allocation information. In step 1810, the HARQ feedback based on the decoding result is transmitted to the base station in subframe f of frame b.

Subsequently, in step 1812, the next allocation information may be transmitted in subframe h of frame c, which is a designated period. In addition, when the HARQ feedback is detected as NACK, the DL HARQ burst may be retransmitted in step 1814.

19, the system configuration information is transmitted from the base station BS to the terminal MS in step 1902. After the UE acquires the system information through the system configuration information and accesses the base station, in step 1904, the base station and the terminal may perform data communication.

In step 1906, allocation information including or indicating a frame index, a subframe index, a long TTI length, and MAP related information (relevance) for HARQ operation timing is transmitted from the base station to the terminal. (DL subframe 1 of frame i) The terminal decodes the allocation information to extract necessary information, and in particular, a frame index on which a previous HARQ operation is performed according to at least one of the above-described embodiments of the present invention. And the subframe index.

In step 1908, the UE transmits a UL HARQ burst in subframe h of frame a according to the allocation information, and the base station decodes the UL HARQ burst according to the allocation information. In step 1910, HARQ feedback or next allocation information according to the decoding result is transmitted to the terminal in subframe f of frame b. When the HARQ feedback is detected as NACK, in step 1912, the UL HARQ burst may be retransmitted in subframe h of frame c, which is a designated period.

In order to implement at least one of the embodiments of the present invention, a base station or a terminal includes a controller configured as a processor, a memory for storing program codes and related parameters for the operation of the controller, and under the control of the controller. It may be configured as a transceiver that exchanges signaling messages or data traffic with a station. The controller controls HARQ timing for the operation of the transceiver according to at least one of the above-described embodiments.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

Claims (30)

A method for operating a hybrid automatic repeat request (HARQ) in a wireless mobile communication system using a frame composed of a plurality of subframes for communication,
determining, according to the data burst allocation information in the l- th downlink (DL) subframe of the i-th frame, a HARQ title �� including DL data burst for DL HARQ transmission and transmission time points of HARQ feedback;
And performing a HARQ operation according to the determined HARQ timing.
At least one frame index and the at least one subframe index indicating the HARQ timing are determined by using the i and l .
The method of claim 1, wherein when the frequency division multiplexing (FDD) scheme is used, the HARQ timing is determined by a table below or by a table including result values by a formula of the following table. .

Here, l is a subframe index provided with the allocation A (Advanced) -MAP information element (IE) including the data burst allocation information, i is a frame index provided with the allocation A-MAP IE, m is the The subframe index at which the transmission of the HARQ subpacket corresponding to the data burst is started, n is the subframe index at which the HARQ feedback is transmitted, j is the frame index at which the HARQ feedback is transmitted, and F is the subframe per frame. N, where N is the number of frames per superframe, is 4 when each superframe consists of 4 frames, and z denotes a DL HARQ feedback offset.
The method of claim 2, wherein the DL HARQ feedback offset z is determined by the following equation according to a data burst processing time for the HARQ subpacket.

Where ceil () denotes a ceiling function, N _TTI denotes the number of subframes occupied by the HARQ subpacket, and Rx_time denotes the data burst processing time.
The method of claim 2, wherein the retransmission of the data burst corresponding to the HARQ feedback,
HARQ operation method characterized in that starts from the same sub-frame index m after a predetermined number of frames from the transmission of the data burst
The method of claim 2, wherein the performing of the HARQ operation is performed by:
Transmitting, by the base station, the HARQ subpacket to the terminal starting from the m th DL subframe of the i th frame;
And receiving, by the base station, the HARQ feedback for the HARQ subpacket from the terminal through an nth UL subframe of the jth frame.
The method of claim 2, wherein the performing of the HARQ operation is performed by:
Receiving, by the terminal, the HARQ subpacket from the base station starting from the m-th DL subframe of the i-th frame;
And transmitting, by the terminal, the HARQ feedback for the HARQ subpacket to the base station through an nth UL subframe of the jth frame.
The HARQ timing method of claim 1, wherein when a long TTI transmission is used in which the data burst occupies two or more subframes in a frequency division multiplexing (FDD) scheme, the HARQ timing is determined by the following equation. HARQ operation method, characterized in that determined by a table containing the result values by the formula of the following table.

Where l is a subframe index provided with allocation A (Advanced) -MAP information element (IE) containing the data burst allocation information, i is a frame index provided with allocation A-MAP IE, and m is the data The subframe index at which the transmission of the HARQ subpacket corresponding to the burst is started, n is the subframe index at which the HARQ feedback is transmitted, j is the frame index at which the HARQ feedback is transmitted, and F is the number of subframes per frame. N is the number of frames per superframe, and each superframe consists of four frames, where z is a DL HARQ feedback offset, and x _n ⁱ represents the x _n th subframe of the i th frame. .
2. The method of claim 1, wherein the HARQ timing is determined by a table below or by a table including result values by a formula of the following table when a time division multiplexing (TDD) scheme is used.

Here, each frame is composed of D subframes for downlink transmission and U subframes for uplink transmission, where l is an Advanced A-MAP information element (IE) including the data burst allocation information. Is a subframe index provided, and has a range from 0 to D-1, i is a frame index provided with the allocation A-MAP IE, and m is a subframe at which transmission of a HARQ subpacket corresponding to the data burst is started. A frame index, n is a subframe index to which the HARQ feedback is transmitted, j is a frame index to which the HARQ feedback is transmitted, N is the number of frames per superframe, and 4 when each superframe consists of 4 frames. Where z is the DL HARQ feedback offset, K is calculated as -ceil {(UD) / 2} if D is less than U, and K = floor {(DU) / 2} if D is greater than or equal to U Calculated by
10. The method of claim 8, wherein the DL HARQ feedback offset z is determined by the following equation according to the data burst processing time for the HARQ subpacket.

Here, N _TTI refers to the number of subframes occupied by the HARQ subpacket, and Rx_time refers to the data burst processing time.
9. The method of claim 8, wherein the retransmission of the data burst corresponding to the HARQ feedback begins at the same subframe index m after a predetermined number of frames from the transmission of the data burst.
The method of claim 8, wherein the subframe indexes l, m, n are
When used as DL subframe indexes, the range is from 0 to D-1, and D means the number of DL subframes used in the interval excluding the interval supporting the legacy system in each frame.
When used as UL subframe indexes, the range is from 0 to U-1, and U means the number of UL subframes used in the interval excluding the interval supporting the legacy system within each frame.
The frame indexes are calculated using subframe index order corresponding to the entire section including the section supporting the legacy system in each frame.
The method of claim 8, wherein the subframe indexes l, m, n are
When used as DL subframe indexes, it means the rearranged subframe indexes for DL subframes used for communication to the corresponding relay station to the terminal,
When used as UL subframe indexes, the subframe indexes are rearranged for UL subframes used for communication from the terminal to the corresponding relay station.
The frame indexes, HARQ operation method, characterized in that calculated using the sub-frame index order corresponding to the entire interval used for communication with the corresponding relay station in each frame.
The method of claim 8, wherein the performing of the HARQ operation comprises:
Transmitting, by the base station, the HARQ subpacket to the terminal starting from the m th DL subframe of the i th frame;
And receiving, by the base station, the HARQ feedback for the HARQ subpacket from the terminal through an nth UL subframe of the jth frame.
The method of claim 8, wherein the performing of the HARQ operation comprises:
Receiving, by the terminal, the HARQ subpacket from the base station starting from the m-th DL subframe of the i-th frame;
And transmitting, by the terminal, the HARQ feedback for the HARQ subpacket to the base station through an nth UL subframe of the jth frame.
The method of claim 1,
In a time division multiplexing (TDD) scheme, when an allocation A-MAP IE including the data burst allocation information indicates a long TTI transmission and l is not 0, transmission of a HARQ subpacket corresponding to the data burst is performed. starting from the 0th DL subframe of the (i + 1) th frame, the HARQ feedback for the HARQ subpacket is transmitted in the n'th UL subframe of the j'th frame,
Herein, the long TTI transmission means that the HARQ subpacket occupies two or more subframes.
The j 'and n' is determined by the following equation, or HARQ operation method characterized in that determined by a table including the result values by the formula of the following table.

A method for operating a hybrid automatic repeat request (HARQ) in a wireless mobile communication system using a frame composed of a plurality of subframes for communication,
In response to the data burst allocation information in the l- th downlink (DL) subframe of the i-th frame, it includes UL data burst and ULQ burst transmission time for uplink (UL) HARQ transmission and retransmission timing of the data burst. Determining a HARQ timing;
And performing a HARQ operation according to the determined HARQ timing.
The at least one frame index and the at least one subframe index indicating the HARQ timing are determined by using the i and l .
17. The method of claim 16, wherein when the frequency division multiplexing (FDD) scheme is used, the HARQ timing is determined by a table below or by a table including result values by a formula of the following table. .

Here, l is a subframe index provided with the allocation A (Advanced) -MAP information element (IE) including the data burst allocation information, i is a frame index provided with the allocation A-MAP IE, m is the The subframe index at which the transmission of the HARQ subpacket corresponding to the data burst is started, j is the frame index at which the HARQ subpacket is transmitted, F is the number of subframes per frame, and N is the number of frames per superframe. 4 if each superframe consists of four frames, k means a frame index to which the HARQ feedback is transmitted.
18. The method of claim 17, wherein the UL HARQ transmission offset z and the UL HARQ feedback offset w are determined by the following equation according to the data burst processing time for the HARQ subpacket or include result values by the formula of the following table. HARQ operating method, characterized in that determined by the table.

Where ceil () denotes a ceiling function, floor () denotes a floor function, N _TTI denotes the number of subframes occupied by the HARQ subpacket, and Rx_time denotes the data burst processing time.
18. The HARQ operation of claim 17, wherein a time point at which retransmission of the data burst corresponding to the HARQ feedback is started is determined by a table below or a table including result values by a formula of the following table. Way.

Here, p denotes a frame index at which retransmission of the HARQ subpacket starts when the HARQ feedback indicates NACK, v denotes a UL HARQ transmission offset, and w denotes a UL HARQ feedback offset.
The method of claim 17, wherein performing the HARQ operation comprises:
Receiving, by the base station, the HARQ subpacket from the terminal starting from the mth UL subframe of the jth frame;
Transmitting, by the base station, the HARQ feedback for the HARQ subpacket to the terminal through an lth DL subframe of the kth frame;
And receiving, by the base station, retransmission of the HARQ subpacket from the terminal, starting from the mth UL subframe of the pth frame.
The method of claim 17, wherein performing the HARQ operation comprises:
Transmitting, by the terminal, the HARQ subpacket to the base station starting from the m th UL subframe of the j th frame;
Receiving, by the terminal, the HARQ feedback for the HARQ subpacket from the base station through an lth DL subframe of the kth frame;
And transmitting, by the terminal, the HARQ subpacket to the base station starting from the mth UL subframe of the pth frame.
17. The method of claim 16, wherein, in the frequency division multiplexing (FDD) scheme, when long TTI transmission is used in which the data burst occupies two or more subframes, the HARQ timing is determined by the following equation, or HARQ operating method, characterized in that determined by the table containing the result values.

Where l is a subframe index provided with allocation A (Advanced) -MAP information element (IE) containing the data burst allocation information, i is a frame index provided with allocation A-MAP IE, and m is the data The subframe index at which the transmission of the HARQ subpacket corresponding to the burst is started, n is the subframe index at which the HARQ feedback is transmitted, j is the frame index at which the HARQ feedback is transmitted, and F is the number of subframes per frame. N is the number of frames per superframe, and each superframe consists of four frames, z is a DL HARQ feedback offset, and p is the HARQ subpacket when the HARQ feedback indicates NACK. Denotes a frame index at which retransmission starts, v denotes a UL HARQ transmission offset, w denotes a UL HARQ feedback offset, and y _n ⁱ denotes a subframe y _{n of} frame i.
17. The method of claim 16, wherein when the time division multiplexing (TDD) scheme is used, the HARQ timing is determined by a table below or by a table including result values by a formula of the following table. .

Here, each frame is composed of D subframes for downlink transmission and U subframes for uplink transmission, where l is an Advanced A-MAP information element (IE) including the data burst allocation information. Is a subframe index provided, and has a range from 0 to D-1, i is a frame index provided with the allocation A-MAP IE, and m is a subframe at which transmission of a HARQ subpacket corresponding to the data burst starts. The frame index, j is the frame index to which the HARQ subpacket is transmitted, KN is the number of frames per superframe, 4 when each superframe consists of four frames, k is the frame index to which the HARQ feedback is transmitted Where v is the UL HARQ transmission offset, w is the UL HARQ feedback offset, K is calculated as -ceil {(UD) / 2} if D is less than U, and K = if D is greater than or equal to U floor {(DU) / 2}.
24. The method of claim 23, wherein the UL HARQ transmission offset v and the UL HARQ feedback offset w are determined by the following equation according to the data burst processing time for the HARQ subpacket.

Here, N _TTI refers to the number of subframes occupied by the HARQ subpacket, and Tx_time and Rx_Time refer to the data burst processing time.
24. The method of claim 23, wherein the time of retransmission of the data burst corresponding to the HARQ feedback is determined by the following table.

Here, p denotes a frame index at which retransmission of the HARQ subpacket is started when the HARQ feedback indicates a NACK.
The method of claim 23, wherein the subframe indexes l, m, n are
When used as DL subframe indexes, the range is from 0 to D-1, and D means the number of DL subframes used in the interval excluding the interval supporting the legacy system in each frame.
When used as UL subframe indexes, the range is from 0 to U-1, and U means the number of UL subframes used in the interval excluding the interval supporting the legacy system within each frame.
The frame indexes, HARQ operation method, characterized in that calculated using the sub-frame index order corresponding to the entire section including the interval supporting the legacy system in each frame.
The method of claim 23, wherein the subframe indexes l, m, n are
When used as DL subframe indexes, it means the rearranged subframe indexes for DL subframes used for communication to the corresponding relay station to the terminal,
When used as UL subframe indexes, the subframe indexes are rearranged for UL subframes used for communication from the terminal to the corresponding relay station.
The frame indexes, HARQ operation method, characterized in that calculated using the sub-frame index order corresponding to the entire interval used for communication with the corresponding relay station in each frame.
The method of claim 23, wherein performing the HARQ operation comprises:
Receiving, by the base station, the HARQ subpacket from the terminal starting from the mth UL subframe of the jth frame;
Transmitting, by the base station, the HARQ feedback for the HARQ subpacket to the terminal through an lth DL subframe of the kth frame;
And receiving, by the base station, retransmission of the HARQ subpacket from the terminal, starting from the mth UL subframe of the pth frame.
The method of claim 23, wherein performing the HARQ operation comprises:
Transmitting, by the terminal, the HARQ subpacket to the base station starting from the m th UL subframe of the j th frame;
Receiving, by the terminal, the HARQ feedback for the HARQ subpacket from the base station through an lth DL subframe of the kth frame;
And transmitting, by the terminal, the HARQ subpacket to the base station starting from the mth UL subframe of the pth frame.
17. The method of claim 16,
In the time division multiplexing (TDD) scheme, when the allocation A-MAP IE indicates a long TTI transmission, transmission of a HARQ subpacket corresponding to the data burst starts at a 0 th UL subframe of a j th frame. The HARQ feedback for the HARQ subpacket is transmitted in the l th UL subframe of the k th frame, and the retransmission of the HARQ subpacket begins in the 0 th UL subframe of the p th frame,
Here, the long TTI transmission means that the HARQ subpacket occupies two or more subframes.

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