KR20110088452A - Apparatus and method for transmitting ul data burst in a wireless access system - Google Patents

Abstract

PURPOSE: An apparatus for transmitting UL data burst in a wireless access system is provided to transmit UL resource which is allocated from a base station. CONSTITUTION: A base station transmits an UL(UpLink) random access A-MAPSTID in which a CRC is masked by a STID or a multicast STID to a terminal(S410). If the de-masking using the STID or the multicast STID is successes, the terminal transmits the uplink data bursts to the base station through an UL random access A-MAP(S420).

Description

Method and apparatus for transmitting uplink data burst in a wireless access system {APPARATUS AND METHOD FOR TRANSMITTING UL DATA BURST IN A WIRELESS ACCESS SYSTEM}

TECHNICAL FIELD The present disclosure relates to a wireless access system, and more particularly, to a method and apparatus for transmitting contention-based uplink data bursts.

The terminal may transmit uplink data to the base station through a random access process and a scheduled access process.

In general, when there are few users in a cell, a random access process is more efficient in terms of latency and throughput than a scheduled access process.

When there are more users in the cell, the probability of contention of random access is increased and the efficiency for uplink transmission is drastically reduced.

However, in case of large coverage such as cellular network, centralized control through scheduling is efficient when there are many users.

Small cells such as femto-cells are cellular based, but random access is efficient due to fewer users in the cell.

Hereinafter, a general random access process will be briefly described with reference to the accompanying drawings.

1 illustrates an uplink resource allocation procedure of a terminal using a contention-based request scheme.

Referring to FIG. 1, the UE transmits a randomly selected CDMA code to a slot randomly selected from a region allocated for a bandwidth request in uplink (S110).

If the base station recognizes the CDMA code sent by the terminal, the base station allocates a resource for transmitting the bandwidth request message by the terminal using the CDMA allocation information element (CDMA_Allocation_IE) (S120).

The terminal receiving the information on the uplink resource for the transmission of the bandwidth request message transmits the bandwidth request message to the corresponding resource region. In this case, the terminal may use a bandwidth request header (BR header), and the header includes information on the size of the request bandwidth (S130).

If the bandwidth requested by the terminal is available, the base station allocates uplink resources to the terminal (S140).

The terminal transmits data to the allocated uplink resource (S150).

2 is a diagram illustrating an example of a three-step random access based bandwidth request procedure.

In the broadband wireless access system, the terminal may use a random access method of 3 steps or 5 steps. The 5-step random access method may be used independently of the 3-step random access method, and may be used as a fall-back mode in the 3-step method.

The Advanced Mobile Station (AMS) transmits a bandwidth request preamble sequence and a Quick Access message to a serving advanced base station (S-ABS) at a randomly selected opportunity ( S210).

In this case, the fast access message may include a station ID, which is uplink bandwidth request information, and a BR index indicating a bandwidth request size and QoS.

The base station may transmit a BR ACK A-MAP information element indicating the reception status for the BR preamble sequence and the fast access message transmitted by each terminal to the terminals in the form of broadcast / multicast (S220).

In addition, the base station, which has normally received the BR preamble sequence and the fast access message, allocates uplink resources to each user equipment, and assigns uplink resource allocation information to the UL basic assignment A-MAP IE. It transmits to each terminal through (S230).

The terminal may transmit uplink data to the base station through the allocated uplink transmission region. In this case, the terminal may transmit additional uplink bandwidth request information to the base station together (S240).

3 is a diagram illustrating an example of a 5-step random access based bandwidth request procedure as a 3 step failure response method.

The terminal transmits the BR preamble sequence (or BR code), the uplink bandwidth request information (Station ID), the BR index indicating the request size and the QoS to the base station using the fast access message (S310).

The base station may transmit the BR preamble sequence transmitted by each terminal and the reception status of the fast access message to the terminals through the BR ACK A-MAP information element. However, the BR preamble sequence is decoded normally, but it is assumed that the fast access message has an error. Accordingly, the BR ACK A-MAP information element indicates that the BR preamble sequence has a normal reception error in the fast access message (S320).

The base station, which normally receives only the BR preamble sequence transmitted by the terminal, allocates an uplink resource for the terminal to transmit a bandwidth request (BW-REQ) message through the CDMA Allocation A-MAP IE. Assign to (S330).

In step S330 the CDMA A-MAP information element may be transmitted to the terminal in the form of a grant for independent BR.

The mobile station transmits a BW-REQ message (e.g. independent BR header form) to the base station through the allocated area (S340).

The base station receiving the BW-REQ message transmitted by the terminal allocates uplink resources to the terminal using UL basic assignment A-MAP IE or grant message for uplink data transmission. (S350).

The terminal transmits UL data to the base station through the allocated uplink resource region. In this case, the terminal may transmit additional uplink bandwidth request information to the base station together (S360).

FIG. 3 is a 5-step random access method as a failure remedy method of the 3-step random access method of FIG. However, the general 5-step method differs from FIG. 3 only in that the terminal does not send the fast access message in step S310, and the remaining steps may be performed using the steps described in FIG.

As described above, the general random access procedure has a problem in that a time is delayed until uplink data burst transmission because uplink resources are allocated at the request of the UE and uplink data burst transmission must be performed through the allocated resource region.

The present specification provides a method for enabling a terminal to use UL resources not used by a base station for uplink data burst transmission through contention-based random access.

In addition, the present invention provides a method for transmitting and receiving data without making unnecessary bandwidth requests in a small environment.

In the present specification, in a method of transmitting an uplink data burst of a terminal in a wireless access system, resource allocation information for contention-based uplink data burst transmission and number of UEs that attempt contention-based uplink data burst transmission are determined. Receiving from the base station a first message comprising control information; And transmitting an uplink data burst to the base station through the resource region allocated from the resource allocation information based on the control information.

The control information may be MCS bound information having a CQI feedback level value reported by the terminal.

In addition, the control information is characterized in that the minimum access class (Minimum Access Class) information.

The uplink data burst may be transmitted to the base station when the latest CQI feedback value of the terminal or the access class of the terminal has a value equal to or greater than the control information.

In addition, the first message may be a random access map message (Random Access A-MAP).

The first message may be transmitted after being CRC masked with a broadcast STID or a multicast STID.

The resource allocation information may include at least one of a resource allocation position, a resource allocation region size, and MCS information, and the first message may include at least one of maximum retransmission count information and HARQ ACK channel information. do.

In addition, comparing the size of the resource allocation area and the size of the uplink data burst for transmission to the base station; And as a result of the comparison, if the size of the uplink data burst to be transmitted is larger, transmitting a message for bandwidth request to the base station.

In addition, receiving an uplink basic allocation map message from the base station; And transmitting the remaining uplink data burst to the base station through the resource region allocated in the uplink basic allocation map message.

The message for bandwidth request is a bandwidth request extension header, and the bandwidth request extension header is piggybacked with an uplink data burst.

In addition, the uplink data burst is transmitted in a MAC PDU, characterized in that the MAC PDU includes a terminal identifier for identifying the terminal.

In addition, receiving an indicator from the base station indicating whether the first message is transmitted; And determining whether to monitor the first message by using the received indicator.

The first message may further include total stream number (TNS) information indicating the total number of streams used for uplink data burst transmission.

In addition, by selecting any one of the total number of streams, characterized in that for transmitting the uplink data burst to the base station via the selected stream.

In addition, the present specification provides a terminal for uplink data burst transmission in a wireless access system, the memory; A wireless communication unit for transmitting and receiving wireless signals with the outside; And resource allocation information for contention-based uplink data burst transmission and control information for determining the number of terminals attempting contention-based uplink data burst transmission from the base station. And control the wireless communication unit to transmit an uplink data burst to the base station through a resource region allocated from the resource allocation information based on the control information.

The control unit may control to transmit the uplink data burst to the base station when the latest CQI feedback value of the terminal or the access class of the terminal has a value equal to or greater than the control information.

In addition, the controller compares the size of the resource allocation region included in the resource allocation information with the size of the uplink data burst for transmission to the base station, and as a result of the comparison, when the size of the uplink data burst to be transmitted is larger, And controlling the wireless communication unit to transmit a message for bandwidth request to the base station.

The control unit may control the wireless communication unit to receive an uplink basic allocation map message from the base station, and transmit the remaining uplink data burst to the base station through a resource region allocated in the uplink basic allocation map message. It characterized in that for controlling the wireless communication unit.

The bandwidth request message is a bandwidth request extension header, and the controller controls the wireless communication unit to piggyback and transmit the bandwidth request extension header and an uplink data burst.

In the present specification, by allocating UL resources not used by the base station to the terminal, when there is uplink data to be transmitted by the terminal, the uplink data is allocated through the UL resources allocated from the base station without resource waste and time delay caused by code-based bandwidth request. There is an effect that can be transmitted.

In addition, even in a system having a small number of users, such as a femto cell, even if the contention probability of random access is small, data can be transmitted more efficiently than a scheduling method using a code-based bandwidth request.

1 is a diagram illustrating an uplink resource allocation procedure of a terminal using a contention-based request method.
2 illustrates an example of a three-step random access based bandwidth request procedure.
3 is a diagram illustrating an example of a 5-step random access based bandwidth request procedure as a 3 step failure response method;
4 illustrates a contention-based uplink data transmission method according to an embodiment of the present specification.
5 is a diagram illustrating a contention-based uplink data transmission method through a BR header when the grant size is insufficient according to another embodiment of the present disclosure.
6 is a diagram illustrating a contention-based uplink data transmission method through piggyback of BR EH and some UL data when grant size is insufficient according to another embodiment of the present disclosure.
7 is a block diagram illustrating a wireless communication system according to an exemplary embodiment of the present specification.

Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present specification will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present specification.

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

Embodiments in the present specification have been described with reference to the data transmission and reception relationship between the base station and the terminal. Here, the base station has a meaning as a terminal node of the network that directly communicates with the terminal. The specific operation described as performed by the base station in this document may be performed by an upper node of the base station in some cases.

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

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

In the case of a hardware implementation, a method according to embodiments of the present disclosure may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs). Field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

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

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

First Embodiment

A first embodiment provides a contention-based uplink data transmission method using random access A-MAP.

Competition based Contention - based Random connections () Random Access Resource allocation method

The base station transmits a CRC masked control message to the terminal using a predetermined identifier (ID). Here, the control message may be Random Access A-MAP or PDCCH. In addition, the control message may be transmitted every frame or every subframe, and may be periodically or aperiodically transmitted to the terminal at a predetermined position or any position of the frame or subframe.

Hereinafter, a case of Random Access A-MAP (RA A-MAP) as an example of the control message will be described.

The control message may include a resource allocation position for uplink data burst transmission of the terminal, Modulation and Coding Scheme (MCS) information, a maximum number of retransmissions, HARQ ACK channel information, and the like.

The terminal assigned the identifier (ID) from the base station (ie, the terminal to which the RA is allowed) receives the Random Access A-MAP from the base station as needed for uplink data burst transmission. In this case, the Random Access A-MAP may be broadcast by a base station or transmitted by a multicast scheme.

The terminal transmits an uplink data burst to the base station through the resource region allocated by the received Random Access A-MAP.

UL Random Access  A-MAP ( UL RA  A- MAP )

The base station allocates the available resources to the terminal through UL RA A-MAP. In this case, the UL RA A-MAP transmitted to the terminal can be received by all the terminals by a broadcast method. In this case, the base station transmits UL RA A-MAP to the terminal by masking the well-known STID in the CRC.

In addition, the UL RA A-MAP transmitted to the terminal may be received by a terminal of a specific group by a multicast scheme. In this case, the base station transmits the UL RA A-MAP to the UE of a specific group by masking the Multicast STID to the CRC.

Among the terminals that have received the UL RA A-MAP from the base station, the terminal having uplink data to be transmitted to the base station transmits a data burst to the resource region allocated by the received UL RA A-MAP.

Here, the area allocated by the UL RA A-MAP corresponds to an area where contention occurs by a plurality of terminals that receive the UL RA A-MAP from a base station.

Therefore, when a plurality of terminals transmit an uplink data burst to the area, a reception error may occur in the base station.

In this case, in case of supporting maximum retransmission by HARQ retransmission, if contention occurs in the region, resource waste may occur due to meaningless retransmission.

Therefore, the UL RA A-MAP may include information for limiting the maximum number of retransmissions for retransmission or may not perform a retransmission process for uplink data burst transmission by the UL RA A-MAP.

Contention  How to adjust

In addition, in order to solve the case where a contention occurs and a reception error occurs, the number of UEs attempting to transmit an uplink data burst may be adjusted. In relation to the method for controlling the number of terminals, a static method and a dynamic method may be exemplified.

1. Static Control (How to adjust the number of terminals using STID)

In the static control, that is, a method for adjusting the number of terminals attempting to transmit uplink data using STID, the base station pre-allocates a well know STID (RNTI in 3GPP) so that all terminals can know the STID. can do. In this case, UL RA A-MAP is transmitted to all terminals by a broadcast method.

Alternatively, the base station allocates a multicast STID for each terminal during registration with the terminal, so that only a specific group terminal can transmit an uplink data burst through a resource region allocated by the UL RA A-MAP. You can do that.

In another method, the base station allocates a multicast STID to a specific flow identifier (FID) during service negotiation with the terminal to allow access to the base station only for specific services of specific terminals to adjust the number of terminals. Can be.

2. Dynamic user control (how to adjust the number of terminals using UL RA A-MAP)

The base station may explicitly include the requirements of the terminal that can be transmitted in the UL RA A-MAP to adjust the number of terminals, thereby reducing a reception error due to contention occurrence.

The base station may adjust the number of terminals by transmitting distance (receive performance) information or access priority information to the terminal including the UL RA A-MAP.

In addition, the base station may include an MCS boundary in the UL RA A-MAP to transmit to the terminal. In this case, based on the current CQI report transmitted to the base station, only terminals having an MCS above a certain MCS boundary may attempt to transmit an uplink data burst through the allocated area.

For example, it is assumed that the CQI feedback value reported to the base station has a value from 0 to 15. In this case, assuming that the MCS boundary value included in the UL RA A-MAP is 4, in order to transmit an uplink data burst through the region allocated by the UL RA A-MAP, the CQI feedback value reported to the base station is 4 or more. It must be a terminal.

In addition, the base station may transmit a minimum access class (minimum access class) in the UL RA A-MAP to the terminal. In this case, only terminals having a service whose access class of the current terminal is greater than or equal to the minimum included in the UL RA A-MAP may attempt to transmit an uplink data burst.

In addition, the base station may inform the terminal through a message such as AAI_SCD, AAI_SBC / REG-RSP whether the UL RA transmission is supported.

In this case, the terminal may determine whether to monitor the UL RA A-MAP transmitted from the base station by checking the information indicating whether the base station supports the UL RA transmission.

Table 1 below shows an example of a format of UL Random Access A-MAP (UL RA A-MAP) when only one stream is used according to an embodiment of the present specification.

Syntax Size in bits Description / Notes UL Random Access A-MAP IE () { - - A-MAP IE Type 4 UL random access A-MAP IE I _sizeoffset 5 Offset used to compute burst size index Resource Index 11 5 MHz: 0 in first 2 MSB bits + 9 bits for resource index
10 MHz: 11 bits for resource index
20 MHz: 11 bits for resource index
Resource index includes location and allocation size Long TTI Indicator One Indicates number of subframes spanned by the allocated resource.
0b0: 1 subframe (default)
0b1: 4 UL subframes for FDD or all UL subframes for TDD
If number of DL subframes, D is less than number of UL subframes, U, Long TTI Indicator = 0b1 HFA 6 HARQ Feedback Allocation Number of Retransmission 2 Maximum number of  retransmissions if decoding is failed .
0 b00 : 0, 0 b01 : 1, 0 b10 : 2, 0b11: 3 MCS  Bound ( Lower ) 4 The MCS bound for this  transmission. AMSs whose latest  nominal MCS reported  is equal or larger than MCS  Bound is allowed to transmit  the data burst through this allocation . MCS  Bound ( Upper ) 4 The MCS bound for this  transmission. AMSs whose  latest nominal MCS reported is  equal or lesser than MCS Bound  is allowed to transmit the data burst through this allocation . Minimum Access Class 2 PDU whose access class is  equal or larger than minimum  access class is allowed to be  sent in this allocation . Reserved 5

Referring to Table 1, the RA A-MAP includes a retransmission count field, an MCS boundary field, and a minimum access class field.

Here, the retransmission number field is a field indicating the maximum number of times that the terminal can retransmit when uplink data burst transmission of the terminal fails. This is to reduce unnecessary retransmissions.

In addition, the MCS Bound field indicates an MCS reference value of a terminal capable of transmitting contention UL. Only terminals that have the latest reported MCS value through CQI greater than or equal to the MCS Bound value indicate that uplink data bursts may be transmitted through a resource region allocated through RA A-MAP. That is, only UEs having an MCS value equal to or greater than the MCS boundary value may attempt transmission based on the CQI report of the UE.

In addition, the Minimum Access Class field indicates that PDUs whose access class is greater than or equal to the minimum access class are allowed to be transmitted through the resource area allocated by the RA A-MAP.

That is, only terminals having a service whose access class is the minimum access class or more may attempt to transmit an uplink data burst.

Table 2 below shows an example of a format of UL Random Access A-MAP (UL RA A-MAP) when using MU-MIMO according to another embodiment of the present specification.

Syntax Size in bits Description / Notes UL Random Access A-MAP IE () { - - A-MAP IE Type 4 UL random access A-MAP IE I _sizeoffset 5 Offset used to compute burst size index Resource Index 11 5 MHz: 0 in first 2 MSB bits + 9 bits for resource index
10 MHz: 11 bits for resource index
20 MHz: 11 bits for resource index
Resource index includes location and allocation size Long TTI Indicator One Indicates number of subframes spanned by the allocated resource.
0b0: 1 subframe (default)
0b1: 4 UL subframes for FDD or all UL subframes for TDD
If number of DL subframes, D is less than number of UL subframes, U, Long TTI Indicator = 0b1 TNS 2 Total Number of streams in  the LRU for CSM
0 b00 : One stream only , 0 b01 : 2 streams, 0 b10 3 streams , 0b11: 4 streams HFA 6 HARQ Feedback Allocation Number of Retransmission 2 Maximum number of  retransmissions if decoding  is failed.
0 b00 : 0, 0 b01 : 1, 0 b10 : 2, 0b11: 3 MCS Bound 4 The MCS bound for this transmission. AMSs whose latest nominal MCS reported is equal or larger than MCS  Bound is allowed to transmit  the data burst  through this allocation . Minimum Access Class 2 PDU whose access class is  equal or larger than  minimum access class is  allowed to be sent in this  allocation. Reserved 5

Referring to Table 2, RA A-MAP includes a TNS (Total Number of Stream) field.

Here, the TNS field represents the total number of streams that can be received by the terminal. That is, the base station informs the total number of receivable streams through the TNS, and the terminal can randomly select among the available streams and transmit data in one stream.

Terminal confirmation AMS identification ) Way

As shown in Table 1, since the UL RA A-MAP transmitted by the base station does not have information about the terminal, when transmitting data in the resource area allocated to the UL RA A-MAP, the terminal transmits data to the MAC PDU. ID) to the base station.

For example, in the IEEE 802.16m system, the terminal transmits the STID to the base station, thereby providing information on the terminal for transmitting uplink data to the base station.

Here, the terminal may transmit the BR Header including the STID to the base station.

In addition, the UE may transmit an Extended Header (EH) that informs the STID of the UL MAC PDU.

When transmitting an extended header (EH) indicating the STID, STID EH may be configured as shown in Table 3 below as an example.

EH Type (4) STID (MSB) (4) STID (LSB) (8)

In case of 3GPP LTE, in order to inform the base station of the information of the terminal, the terminal transmits the terminal specific identifier control element (C-RNTI control element) in the MAC PDU to the base station.

Hereinafter, a contention-based uplink data burst transmission method according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. (If there is no HARQ retransmission for an uplink data burst transmitted by a terminal, take an example. do.)

First, FIG. 4 is a diagram illustrating a contention-based uplink data transmission method according to an embodiment of the present specification.

Referring to FIG. 4, the base station transmits a UL Random Access A-MAP whose CRC is masked by STID or Multicast STID well-known to the terminal in a downlink subframe or frame (S410).

Here, the base station may transmit the UL Random Access A-MAP to a predetermined subframe or frame position, and may transmit to the position of any subframe or frame. In addition, the base station may transmit the UL Random Access A-MAP to the terminal periodically or aperiodically (or event-driven).

When the demasking is successful using the well-known STID or the multicast STID, the terminal transmits an uplink data burst to the base station through the UL Random Access A-MAP.

5 is a diagram illustrating a contention-based uplink data transmission method through a BR header when the grant size is insufficient according to another embodiment of the present specification.

Since S501 is the same as step S401, description thereof will be omitted and only differences will be described.

When the resource allocation area size received through the UL RA A-MAP is smaller than the size of the data burst to be transmitted to the base station, the terminal transmits a BR header to the base station for bandwidth request. (S520) Here, the UL RA A-MAP is transmitted. The uplink data burst corresponding to the size of the resource allocation region received through the UE can be transmitted to the base station.

Here, when the resource allocation area size received through the UL RA A-MAP is larger than the size of the data burst to be transmitted to the base station, the terminal is the same as the method of FIG.

Next, the terminal receives a UL Basic Assignment A-MAP (UL AA-MAP) from the base station (S530), and transmits an uplink data burst through the resource region allocated by the received UL AA-MAP. S540) Here, the terminal may transmit the remaining data burst through the resource region allocated by the UL AA-MAP.

6 is a diagram illustrating a contention-based uplink data transmission method through piggyback of BR EH and some UL data when the grant size is insufficient according to another embodiment of the present specification.

Since S601 is the same as step S401, the description thereof will be omitted and only the differences will be described.

When the size of the resource allocation region received through the UL RA A-MAP is smaller than the size of the data burst to be transmitted to the base station, the terminal allocates the resource region size allocated through the UL RA A-MAP for bandwidth request for UL data transmission. A part of uplink data and piggyback BR extended header are transmitted to the base station (S620).

Next, the terminal receives a UL Basic Assignment A-MAP (UL AA-MAP) from the base station (S630), and transmits the remaining UL data burst through the resource region allocated by the received UL AA-MAP. S640)

If a plurality of UL RA A-MAPs are transmitted from the base station, the terminal may determine a resource to be used for uplink data burst transmission by using a method used in random access.

Second Embodiment

The second embodiment provides a contention-based uplink data burst transmission method using Random Access A-MAP in a machine-to-machine (M2M) environment.

First, the device-to-device communication (M2M) will be briefly described.

Machine to Machine (M2M) refers to communication between an electronic device and an electronic device as it is. In other words, it means communication between things. In general, although it refers to wired or wireless communication between electronic devices or communication between a device controlled by a person and a machine, it is used to mean a wireless communication between an electronic device and an electronic device, that is, between devices. In addition, M2M terminals used in a cellular network are inferior in performance or capability to general terminals.

In addition, the characteristics of the M2M environment is as follows.

1. A large number of terminals in a cell

2. Small amount of data

3. Low transmission frequency

4. Limited Number of Data Characteristics

5. Not sensitive to time delay

Hereinafter, a contention-based UL data transmission method in inter-device communication (M2M) will be described in detail.

Group - wise scheduling

When the base station schedules (scheduling) for resource allocation in the unit of a terminal, the burden of administration costs increases due to the large number of M2M terminals. Accordingly, the base station can perform scheduling in units of M2M groups.

Here, the base station allocates resources in units of M2M Group, but by appropriately adjusting the number and ratio, the contention UL transmission method can be applied in the M2M environment.

That is, the base station may perform scheduling between M2M groups by considering the priority, service type, resource allocation size, etc. between the M2M groups.

Polling ( Polling Resource allocation

In an M2M environment, when allowing random access to the terminals, a large number of terminals may degrade the performance of the existing terminal.

Since the bandwidth required by the terminal in the M2M environment will be relatively constant, the complex bandwidth request BR also does not have much meaning.

Accordingly, the base station may allocate a resource using RA A-MAP without allowing a bandwidth request to the M2M terminal. Here, the base station may transmit information indicating that the bandwidth request is not allowed to the terminal in advance.

In this case, since only a specific M2M terminal attempts to transmit contention-based uplink data, it does not significantly affect the performance of the existing terminal. Therefore, the terminal may store the channel quality indicator (CQI) in the terminal without transmitting the CQI to the base station.

Hereinafter, an operation method of a base station for a contention-based uplink data transmission method in an M2M environment will be described.

First, the base station allocates a multicast STID capable of receiving RA A-MAP to a specific M2M Group. Here, the base station may allocate the multicast STID to a specific M2M group in consideration of the number of terminals, resource allocation size, service type, priority, etc. of the M2M group.

Next, the base station transmits the RA A-MAP to the terminal by masking the corresponding multicast STID to the CRC of the Random Access A-MAP for resource allocation to the specific M2M Group.

The base station may transmit the RA A-MAP to the terminal periodically or aperiodically at the position of a specific subframe or frame.

In this case, when the base station periodically transmits the RA A-MAP to the terminal, the base station may transmit the RA A-MAP to the terminal by providing the relevant period information in the access step or include the RA A-MAP or the Multicast control information.

How to adjust the number of terminals

The base station may adjust the number and characteristics of UEs attempting to transmit an uplink data burst by including and transmitting an MCS boundary (Lower, Upper) in the RA A-MAP.

In addition, the base station can adjust the number of terminals by including a minimum access class (Minimum Access Class) in the RA A-MAP.

Table 4 below shows an example of a format of the RA A-MAP according to the second embodiment.

Syntax Size in bits Description / Notes UL_Random_Access_A-MAP IE () { - - A-MAP IE Type 4 UL random access A-MAP IE I _sizeoffset 5 Offset used to compute burst size index Resource Index 11 5 MHz: 0 in first 2 MSB bits + 9 bits for resource index
10 MHz: 11 bits for resource index
20 MHz: 11 bits for resource index
Resource index includes location and allocation size Long TTI Indicator One Indicates number of subframes spanned by the allocated resource.
0b0: 1 subframe (default)
0b1: 4 UL subframes for FDD or all UL subframes for TDD
If number of DL subframes, D is less than number of UL subframes, U, Long TTI Indicator = 0b1 HFA 6 HARQ Feedback Allocation Number of Retransmission 2 Maximum number of retransmissions if decoding is failed.
0b00: 0, 0b01: 1, 0b10: 2, 0b11: 3 MCS (Lower) 4 The MCS bound for this transmission. AMSs whose latest nominal MCS reported is equal or larger than MCS Bound is allowed to transmit the data burst through this allocation. MCS (Upper) 4 The MCS bound for this transmission. AMSs whose latest nominal MCS reported is equal or lesser than MCS Bound is allowed to transmit the data burst through this allocation. Device ID  Modulo ( DIM ) 2 Device ID To modulo  Value to use (0 b00 : 1, 0 b01 : 2, 0b10: 4, 0 b11 : 8) Acceptance (M) 2 Device ID To DIM to modulo  Only terminal with result M can be transmitted } - -

7 is a block diagram illustrating a wireless communication system according to an exemplary embodiment of the present specification.

The base station 710 includes a control unit 711, a memory 712, and a radio frequency unit (RF) unit 713.

The controller 711 implements the proposed function, process and / or method. Layers of the air interface protocol may be implemented by the controller 711.

The controller 711 may control to transmit an uplink data burst through a resource allocation region received through the RA A-MAP.

The memory 712 is connected to the controller 711 to store a protocol or parameter for multi-carrier operation. The RF unit 713 is connected to the control unit 711 to transmit and / or receive a radio signal.

The terminal 720 includes a controller 721, a memory 722, and a radio communication (RF) unit 723.

The controller 721 implements the proposed function, process and / or method. Layers of the air interface protocol may be implemented by the controller 721. The controller 721 may control to transmit an uplink data burst through a resource allocation region received through the RA A-MAP.

The memory 712 is connected to the controller 721 to store a protocol or parameter for multi-carrier operation. The RF unit 713 is connected to the control unit 721 to transmit and / or receive a radio signal.

The controllers 711 and 721 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and / or a data processing device. The memory 712, 722 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices. The RF units 713 and 723 may include a baseband circuit for processing a radio signal. When the embodiment is implemented in software, the above-described techniques may be implemented with modules (processes, functions, and so on) that perform the functions described above. The module may be stored in the memories 712 and 722 and executed by the controllers 711 and 721. The memories 712 and 722 may be inside or outside the controllers 711 and 721, and may be connected to the controllers 711 and 721 by various well-known means.

700: wireless communication system
710: base station
720: terminal
711, 721: control unit
712, 722: memory
713, 723: radio communication (RF) unit

Claims (23)

In the uplink data burst transmission method of the terminal in a wireless access system,
Receiving a first message from a base station including resource allocation information for contention-based uplink data burst transmission and control information for determining the number of terminals attempting contention-based uplink data burst transmission; And
Based on the control information, transmitting an uplink data burst to the base station through a resource region allocated from the resource allocation information. The method of claim 1,
The control information is characterized in that the MCS bound information having a CQI feedback level value reported by the terminal. The method of claim 1,
The control information is characterized in that the minimum access class (Minimum Access Class) information. 4. The method according to claim 2 or 3,
And transmitting the uplink data burst to the base station when the latest CQI feedback value of the terminal or the access class of the terminal has a value equal to or greater than the control information. The method of claim 1,
Wherein the first message is a random access map message (Random Access A-MAP). The method of claim 1,
The first message is characterized in that the CRC masked and transmitted with a broadcast STID or multicast STID. The method of claim 1,
The resource allocation information includes at least one of a resource allocation location, a resource allocation region size, and MCS information, and the first message includes at least one of maximum retransmission count information and HARQ ACK channel information. . The method of claim 7, wherein
Comparing the size of the resource allocation area with the size of an uplink data burst for transmission to the base station; And
And if the size of the uplink data burst to be transmitted is larger, transmitting a message for bandwidth request to the base station. The method of claim 8,
Receiving an uplink basic assignment map message from the base station; And
And transmitting the remaining uplink data burst to the base station through the resource region allocated in the uplink basic allocation map message. The method of claim 8,
And the message for bandwidth request is a bandwidth request extension header, and the bandwidth request extension header is piggybacked and transmitted with an uplink data burst. The method of claim 1,
The uplink data burst is transmitted in a MAC PDU,
The MAC PDU comprises a terminal identifier for identifying the terminal. The method of claim 1,
Receiving an indicator from the base station indicating whether the first message is transmitted; And
Determining whether to monitor the first message by using the received indicator. The method of claim 1,
The first message may further include total stream number (TNS) information indicating the total number of streams used for uplink data burst transmission. The method of claim 13,
Selecting one of the total stream numbers and transmitting an uplink data burst to the base station through the selected stream; A terminal for uplink data burst transmission in a wireless access system,
Memory;
A wireless communication unit for transmitting and receiving wireless signals with the outside; And
The wireless communication unit is controlled to receive a first message from a base station, the first message including resource allocation information for contention-based uplink data burst transmission and control information for determining the number of terminals attempting contention-based uplink data burst transmission. ,
And controlling the wireless communication unit to transmit an uplink data burst to the base station through the resource region allocated from the resource allocation information based on the control information. 16. The method of claim 15,
The control information is a terminal characterized in that the MCS bound information having a CQI feedback level value reported by the terminal. 16. The method of claim 15,
The control information is a terminal characterized in that the minimum access class (Minimum Access Class) information. The method of claim 16 or 17, wherein the control unit,
And if the latest CQI feedback value of the terminal or the access class of the terminal has a value equal to or greater than the control information, controlling the uplink data burst to be transmitted to the base station. The method of claim 16 or 17, wherein the control unit,
And transmitting the uplink data burst to the base station when the latest CQI feedback value of the terminal or the access class of the terminal has a value equal to or less than the control information. 16. The method of claim 15,
And the first message is a random access map message (Random Access A-MAP). The method of claim 15, wherein the control unit,
Compares the size of the resource allocation region included in the resource allocation information with the size of the uplink data burst for transmission to the base station; and as a result of the comparison, if the size of the uplink data burst to be transmitted is larger, a message for bandwidth request Terminal for controlling the wireless communication unit to transmit to the base station. The method of claim 21, wherein the control unit,
The wireless communication unit is controlled to receive an uplink basic allocation map message from the base station, and the wireless communication unit is controlled to transmit the remaining uplink data burst to the base station through the resource region allocated in the uplink basic allocation map message. Terminal, characterized in that. The method of claim 22,
The bandwidth request message is a bandwidth request extension header, and the control unit is characterized in that for controlling the wireless communication unit to piggyback and transmit the bandwidth request extension header and uplink data burst.

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