WO2012046970A2 - Device and method for allocating radio resources in wireless communication network - Google Patents

Abstract

Disclosed is a method for allocating radio resources in a wireless communication system. Subframes that use only a particular terminal or a particular terminal group are allocated through the period, offset, and number of subframes that are consecutively used, or the subframes are allocated through the period, offset, and bitmap for subframes that are available within one or a plurality of frames, whereby radio resources are effectively allocated.

Description

Apparatus and method for allocating radio resources in a wireless communication network

The present invention relates to an apparatus and method for allocating a radio resource in a wireless communication network. More particularly, the present invention relates to allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are distinguishable in time and having a predetermined period. An apparatus and method are provided.

The mobile communications technology created by the Third Generation Partnership Project (3GPP) is now widely used worldwide, with more than half the world's population. Recently, a technology researched and developed in 3GPP includes an advanced radio access technology commonly known as Long Term Evolution (LTE) and an associated packet architecture core system (System Architecture Evolution).

The LTE downlink transmission scheme is based on orthogonal frequency division multiplexing (OFDM), and a single carrier transmission scheme based on Discrete Fourier Transform Spread (DFTS) -OFDM is used for uplink. Processing for LTE also consists of different protocol hierarchies. The LTE protocol structure, for example, in case of downlink, data to be transmitted enters a processing process in the form of an IP packet on the SAE bearer. IP packets entering the processing process are packet data convergence protocol (PDCP) layers, segmentation / concatenation (IPCP), which perform IP header compression to reduce the number of bits transmitted over the air interface, before they are sent over the air interface. , RLC (Radio Link Control) layer that transmits retransmission management and data in order to upper layer, Medium Access Control (MAC) layer that performs HARQ retransmission and uplink and downlink scheduling, coding / decoding, modulation / demodulation, It will go through several protocol entities, such as the physical layer (PHY), which is responsible for multi-antenna mapping and other common physical layer functions.

Among them, the LTE physical layer is transmitted through a time domain structure of LTE transmission based on a frame having a predetermined length of time. Each frame is identified by a system frame number (SFN). SFN is used to control various transmission periods that may have a period longer than one frame, such as a paging and sleep-mode period or a channel state reporting period. In LTE, one frame consists of a time length of 10 ms each consisting of 10 subframes each having a length of 1 ms.

LTE can operate in both modes of Frequency Division Duplex (FDD) and Time Division Duplex (TDD), and the frame structure is generally similar to the FDD mode and the TDD mode, but has a structure having several different differences.

In order to transmit and receive data between the base station and the terminal, it is required to allocate radio resources classified based on these frames according to a predetermined criterion. However, since one or a plurality of subframes included in one frame may be used only for a specific terminal or a specific terminal group related to a specific service, radio resource allocation is not easy.

An object of the present invention is to provide an apparatus for allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are distinguishable in time and having a predetermined period.

Another object of the present invention is to provide a method for allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are distinguishable in time and having a predetermined period.

In accordance with an aspect of the present invention, an apparatus for allocating a radio resource allocates radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are separated in time and have a predetermined period. An apparatus, comprising: identifying information about a period, an offset, and a subframe to be used of a radio resource allocated to a terminal group consisting of at least one terminal sharing characteristics, and using the same, subframe allocation information for each terminal group And a wireless transmitter for transmitting the configured subframe allocation information to at least one terminal.

According to an embodiment of the apparatus for allocating a radio resource of the present invention, the information on the subframe to be used may include the first subframe indicated by each component and the number of subframes continuously used.

Here, the first subframe indicated by each component may be calculated using at least one of the number of subframes constituting one frame, a frame index, a subframe index, and a period of the configuration.

Here, the subframe indicated by the configuration i as allocation information for each terminal group may be defined according to the following equation,

here,N                      _sf                      Represents the number of subframes constituting one frame,n                      _f Is the frame index,n                      _sf Is the subframe index,T                      _{sf, i}  Is the cycle of configuration i,D                      _{sf, i} Denotes the offset of configuration i,N                      _{consc, i} Denotes the number of consecutively used subframes of configuration i, and "mod" is a modulo operator.

According to an embodiment of the apparatus for allocating a radio resource of the present invention, the information about the subframe to be used may be bitmap information on a subframe available in at least one frame of one period.

Here, the number of bits constituting the bitmap may be calculated by multiplying the number of frames indicated by the bitmap with the number of subframes available in one frame.

When the bitmap indicates allocation information for a plurality of frames, the bitmap may be configured individually and sequentially for each frame.

Offset D _{f, i} of configuration i as allocation information for each terminal group may be defined according to the following equation,

Where n _f represents a frame index, T _{f, i} represents a period of configuration i, D _{f, i} represents an offset of configuration i, and “mod” is a modulo operator.

Here, the subframe allocation information may be transmitted in a broadcast form to all terminals in the cell using broadcast information in a radio resource control (RRC) message.

In addition, the subframe allocation information may be individually transmitted to at least one terminal associated with the subframe allocation information through a signaling radio bearer in a radio resource control (RRC) message.

In accordance with another aspect of the present invention, there is provided a method for allocating a radio resource to at least one terminal in a wireless communication network using a frame structure in which radio resources are separated in time and have a predetermined period. The present invention relates to a method of allocating a mobile station comprising: information on a period, an offset, and a subframe to be used of a radio resource allocated to a terminal group consisting of at least one terminal sharing characteristics, and using the same, assigns a subframe to each terminal group Comprising information and transmitting the configured subframe allocation information to at least one terminal.

Here, the terminal group composed of at least one terminal sharing the characteristics may be a terminal group that receives a nominal MBMS subframe, an LTE-Advanced terminal group, and a terminal group that substantially receives MBMS data. It may include.

According to a method and apparatus for allocating a radio resource in a wireless communication network of the present invention, a subframe using only a specific terminal or a specific group of terminals is allocated through a period and an offset and a number of subframes continuously used, or a period and an offset and Radio resources can be effectively allocated by allocating through bitmaps for subframes available within one or a plurality of frames.

1 is a block diagram of a wireless communication system to which various embodiments of the present invention are applied.

2 is a conceptual diagram illustrating a radio resource allocation method according to an embodiment of the present invention.

3 is a conceptual diagram illustrating a radio resource allocation method according to another embodiment of the present invention.

4 is a conceptual diagram illustrating a radio resource allocation method according to another embodiment of the present invention.

5 is a flowchart of a radio resource allocation method according to an embodiment of the present invention.

As the present invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention. In the following description of the present invention, the same reference numerals are used for the same elements in the drawings and redundant descriptions of the same elements will be omitted.

In the present invention, the base station is used to mean a control device that controls one cell. In an actual communication system, a 'physical base station' may control a plurality of cells. In this case, it may be considered that the 'physical base station' includes several 'base stations' in the present invention. That is, a parameter allocated differently for each cell may be considered that each 'base station' allocates a different value.

 In the present invention, the terminal may be a user equipment (UE), a mobile station (MS), a relay node (RN), or a machine type communication (MTC) device.

1 illustrates a configuration of a wireless communication system to which various embodiments of the present invention are applied.

The wireless communication system to which the present invention can be applied includes at least one base station 100 and at least one user terminal 200 connected to a network including a wired network and the like, and additionally includes a relay 110 and the like according to cell characteristics. can do.

Base station 100 is a wireless end node for transmitting data to the user terminal, the wireless end node may appear in the form of a small or home base station in addition to the general base station to cover a certain service area. The wireless end node may be a relay 110 as shown in FIG. 1. Here, the base station or the relay may be a preferred embodiment of the radio resource allocation apparatus according to the present invention. In order to transmit data to the terminals under its control, the base station 100 or the relay 110 distributes, or allocates, radio resources to the terminals according to a predetermined rule.

Radio resources transmitted and received between the base station (or relay) and the terminal may be configured in subframe units. One frame may include a plurality of subframes.

One or a plurality of subframes of one frame may use only a specific terminal or a specific terminal group. In this embodiment, the specific terminal group may be a terminal group using a multimedia broadcast multicast service (MBMS) or an LTE-Advanced terminal group.

There may be two ways to allocate a subframe using only a specific terminal or a specific terminal group. Here, the subframe may be a downlink subframe or an uplink subframe.

An apparatus for allocating a radio resource according to an embodiment of the present invention includes at least one of allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are separated in time and having a predetermined period, and sharing characteristics. It may be configured to include a control unit for identifying the information about the period, the offset, and the sub-frame to be used, the radio resources allocated to the terminal group consisting of one terminal, and configures the sub-frame allocation information for each terminal group using this information. have.

The radio resource allocation information thus configured is notified to all terminals or related specific terminals in the service area through the radio transmitter of each radio end node 100 or 110. An apparatus for allocating a radio resource according to an embodiment of the present invention may be a base station 100 or a relay 110.

Hereinafter, a radio resource allocation method according to the present invention will be described in more detail.

According to the present invention, a first method of allocating a radio resource is to allocate the number of subframes used consecutively with a period and an offset. Herein, the period and offset are each in subframe units, and the offset is smaller than the period. When one configuration is performed through one cycle and one offset and the number of subframes used in succession, a method of allocating subframes using only a specific UE or a specific UE group may be a combination of one or more configurations. Can be.

The subframe indicated by each component of the first method may be represented by Equation 1 below.

Equation 1

In Equation 1N                  _sf                  Represents the number of subframes constituting one frame,n                  _f Is the frame index,n                  _sf Is the subframe index,T                  _{sf, i}  Is the cycle of configuration i,D                  _{sf, i} Denotes the offset of configuration i,N                  _{consc, i} Denotes the number of consecutively used subframes of configuration i. And "mod" is a modulo operator.

Also, offset of configuration iD                  _{sf, i} Is set based on the first subframe of the first frame. For example, the first frame may be a frame with SFN = 0. The system frame number (SFN) represents a frame index used by the base station and the terminal.

2 is a conceptual diagram illustrating a radio resource allocation method according to an embodiment of the present invention.

In FIG. 2, N _sf is assumed to be 10. 2 shows a state in which radio resources are allocated to two configurations, that is, two terminal groups. It can be seen that the first configuration "Configuration 0" has a period of 10, an offset of 3, and the number of subframes used continuously is one. The second configuration, "Configuration 1" has a period of 20, an offset of 17, and the number of subframes used in succession is two.

According to the present invention, a second method of allocating a radio resource is to allocate a period and an offset and a bitmap for subframes usable within one or a plurality of frames. In this case, the period and the offset are each in units of frames, and the offset is smaller than the period. The second method of allocating radio resources according to the present invention is different from the first method in that the period and offset are in units of frames.

In the second method of allocating radio resources according to the present invention, when the range of the bitmap for the subframes is a plurality of frames, the period is greater than or equal to the number of frames indicated by the bitmap. The number of bits in a bitmap is equal to the product of the number of frames represented by the bitmap by the number of subframes available in one frame. When the number of frames represented by the bitmap is plural, the bitmap may be separately configured in a sequence of bitmaps for the first frame, bitmaps for the second frame, and the like. The bitmap for one frame is sequentially composed of subframes usable in one frame. When one configuration is performed through one period and an offset and one bitmap for subframes available within one or more frames, a method of allocating a subframe using only a specific UE or a specific UE group is one. Or a combination of a plurality of configurations.

The frame indicated by each component of the second method may also be represented by Equation 2.

Equation 2

In Equation 2, n _f represents a frame index, T _{f, i} represents a period of component i, and D _{f, i} represents an offset of component i. In addition, the offset D _{f, i} of the configuration i is set based on the first subframe of the first frame. For example, the first frame may be a frame with SFN = 0. The system frame number (SFN) represents a frame index used by the base station and the terminal.

3 is a conceptual diagram illustrating a radio resource allocation method according to another embodiment of the present invention.

In FIG. 3, it is assumed that the number of subframes constituting one frame is 10. A total of four subframes can be used in one frame, assuming that the second subframe, the fourth subframe, the seventh subframe, and the ninth subframe are used.

3 consists of two configurations. The first configuration, "Configuration 0", has a period of two and an offset of one. The range of the bitmap for the subframes is one frame, in which case the bitmap may consist of a total of four bits, and the bitmap of "configuration 0" may be represented by 0011. Here, 1 means a subframe used, 0 means a subframe not used.

The second configuration, "Configuration 1", has a period of four and an offset of zero. The range of the bitmap for the subframes may be two frames, in which case the bitmap may consist of a total of eight bits, and the bitmap of "Configuration 1" may be represented as 11001000. Here, 1 means a subframe used, 0 means a subframe not used.

A method of allocating a subframe using only a specific terminal or a specific terminal group is called subframe allocation information. The base station transmits the subframe allocation information to the terminal, there is a method for broadcasting to all the terminals in the cell, there is a method for transmitting to the associated terminal individually. The terminal may identify the downlink subframe transmitted from the base station by receiving the subframe allocation information, or may identify the uplink subframe to be transmitted to the base station.

A first embodiment of a method of transmitting subframe allocation information includes a method of broadcasting to all terminals in a cell, and this method is a method of transmitting through RRC broadcasting information (System information) in 3GPP. A second embodiment of a method of transmitting subframe allocation information may be a method of individually transmitting to a related terminal, and this method is a method of transmitting through SRB (Signalling Radio Bearer) of RRC in 3GPP.

Here, the RRC layer above the MAC layer performs various control functions related to setting, changing, and releasing the lower layer in the terminal or the network. Related RRC messages are exchanged between the UE and the network to support various RRC procedures.

Three types of RRC messages are used to convey system information: MIB messages, SIB1 messages, and system information (SI) messages. Here, the system information is configured in the form of a system information block (SIB), and each system information block includes a series of functionally related parameters.

The base station may transmit one or a plurality of subframe allocation information to the terminal. Here, each subframe allocation information indicates a subframe using only a specific terminal or a specific terminal group. According to the subframe allocation information, there may be a terminal that can receive the subframe allocation information, and there may be a terminal that cannot receive the subframe allocation information. There may be a terminal that may not receive subframe allocation information at all, or there may be a terminal that may receive one or a plurality of subframe allocation information.

If the terminal capable of receiving the subframe allocation information receives the subframe allocation information, and the subframe allocation information is related to the terminal, the terminal may use the subframe indicated by the subframe allocation information. On the other hand, if the terminal capable of receiving the subframe allocation information receives the subframe allocation information and the subframe allocation information is not related to itself, the terminal does not use the subframe indicated by the subframe allocation information.

4 is a conceptual diagram of a radio resource allocation method according to another embodiment of the present invention.

In FIG. 4, assume that the entire subframe is divided into three resource groups. Terminal 0 is an LTE terminal, a terminal that does not receive MBMS, terminal 1 is an LTE-Advanced terminal, a terminal that does not receive an MBMS, terminal 2 is an LTE terminal, a terminal that receives an MBMS, terminal 3 is an LTE Assume that the terminal is an Advanced terminal and receives the MBMS.

Here, the terminal group 1 is a terminal group that nominally receives a subframe for MBMS, and resource allocation information for these terminals is called allocation information A, and terminal group 2 is an LTE-Advanced terminal group, and resource allocation information for these terminals is Assume that the allocation information B, the terminal group 3 is actually a terminal group receiving the MBMS data, and assume that the resource allocation information for these terminals is the allocation information C.

Here, the nominal MBMS subframe means a MBSFN (Multimedia Broadcast Single Frequency Network) subframe used for relaying, positioning, and the like. The MBSFN subframe was originally proposed for the MBMS, but may be used for other purposes except for the MBMS, such as relay and positioning. Here, only the system after the LTE-Advanced version, the MBSFN subframe can be used for other purposes except for MBMS, such as relay and positioning. That is, an LTE-Advanced terminal can receive a nominal MBMS subframe and use service related information such as relay and positioning included in the subframe. If the LTE terminal can receive a nominal MBMS subframe, but the data included in the subframe is determined not to be associated with itself is not used.

The operation of the terminals will be described in more detail with reference to FIG. 4.

The base station may transmit the subframe allocation information A so that both the LTE terminal and the LTE-Advanced terminal can receive. In addition, the base station may transmit the subframe allocation information B to be received only to the LTE-Advanced terminal. In addition, the base station may transmit the subframe allocation information C to be received only by the terminal receiving the MBMS.

Since the terminal 0 does not receive the MBMS to the LTE terminal, it can receive only the subframe allocation information A. Although UE 0 receives subframe allocation information A, it is determined that the subframe indicated by subframe allocation information A is not related to itself and does not use this subframe. Accordingly, the base station and the terminal 0 may use only the subframes, that is, the subframes of the resource group A, except the subframe indicated by the subframe allocation information A among the entire subframes.

UE 1 may receive subframe allocation information A and subframe allocation information B. FIG. Although the terminal 1 does not receive the MBMS, unlike the terminal 0, it determines that the subframe indicated by the subframe allocation information A is related to itself, and thus does not exclude the subframe. UE 1 does not exclude the subframe indicated by subframe allocation information A, but does not use all of the subframes indicated by subframe allocation information A. FIG. In addition, the terminal 1 determines that the subframe indicated by the subframe allocation information B is related to the UE, and uses the subframe. Accordingly, the base station and the terminal 1 may use only the subframe of the resource group A and the subframe of the resource group B among the entire subframes.

Terminal 2 may receive the subframe allocation information A and the subframe allocation information C. The terminal 2 determines that the subframe indicated by the subframe allocation information A is related to the terminal 2 and does not exclude the subframe. UE 2 does not exclude the subframe indicated by subframe allocation information A, but does not use all of the subframes indicated by subframe allocation information A. FIG. In addition, the terminal 2 determines that the subframe indicated by the subframe allocation information C is related to the subframe, and uses the subframe. Accordingly, the base station and the terminal 2 may use the subframe of the resource group A and the subframe of the resource group C among the entire subframes.

UE 3 may receive subframe allocation information A, subframe allocation information B, and subframe allocation information C. UE 3 determines that the subframe indicated by subframe allocation information A is related to the UE, and does not exclude the subframe. UE 3 does not exclude the subframe indicated by subframe allocation information A, but does not use all of the subframes indicated by subframe allocation information A. FIG. In addition, the terminal 3 determines that the subframe indicated by the subframe allocation information B is related to the UE, and uses the subframe. In addition, the terminal 3 determines that the subframe indicated by the subframe allocation information C is related to the UE, and uses the subframe. Accordingly, the base station and the terminal 3 may use the subframe of the resource group A, the subframe of the resource group B and the subframe of the resource group C among the entire subframes.

5 is a flowchart of a radio resource allocation method according to an embodiment of the present invention.

Referring to FIG. 5, in the radio resource allocation method according to the present invention, first, information about a period, an offset, and a subframe to be used, is allocated to each terminal group (S501). Here, each terminal group is composed of at least one terminal sharing characteristics. Subsequently, subframe allocation information is configured for each terminal group using the identified information (S502). In step S503, the subframe allocation information thus configured is transmitted to at least one terminal.

Although described with reference to the embodiments above, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the invention as set forth in the claims below. Could be.

Claims (15)

An apparatus for allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are divided in time and having a predetermined period, A control unit which grasps information about a period, an offset, and a subframe to be used of a radio resource allocated to a terminal group including at least one terminal sharing characteristics, and configures subframe allocation information for each terminal group by using the same; And And a radio transmitter for transmitting the configured subframe allocation information to at least one terminal. The method according to claim 1, The information about the subframe to be used, And a number of subframes used consecutively and the first subframe indicated by each configuration. The method according to claim 2, The first subframe indicated by each configuration The apparatus for assigning radio resources, characterized in that it is calculated using at least one of the number of subframes constituting one frame, the frame index and the subframe index, the period of the configuration. The method according to claim 3, The subframe indicated by the configuration i as allocation information for each terminal group is defined according to the following equation,

here,N                  _sf                  Represents the number of subframes constituting one frame,n                  _f Is the frame index,n                  _sf Is the subframe index,T                  _{sf, i}  Is the cycle of configuration i,D                  _{sf, i} Denotes the offset of configuration i,N                  _{consc, i} Denotes the number of consecutively used subframes of configuration i, wherein "mod" is a modulo operator. The method according to claim 1, The information about the subframe to be used, And bitmap information for a subframe available within at least one frame of one period. The method according to claim 5, The number of bits constituting the bitmap is calculated by multiplying the number of frames indicated by the bitmap by the number of subframes available in one frame. The method according to claim 5, Offset D _{f, i} of configuration i as allocation information for each terminal group is defined according to the following equation,

Wherein n _f represents a frame index, T _{f, i} represents a period of configuration i, D _{f, i} represents an offset of configuration i, and “mod” is a modulo operator. The method according to claim 1, The subframe allocation information, The radio resource allocation apparatus, characterized in that transmitted to all the terminals in the cell in the form of broadcast using the broadcast information in the RRC (Radio Resource Control) message. The method according to claim 1, The subframe allocation information, And is individually transmitted to at least one terminal associated with the subframe allocation information through a signaling radio bearer in a radio resource control (RRC) message. A method of allocating radio resources to at least one terminal in a wireless communication network using a frame structure in which radio resources are divided in time and having a predetermined period, Identifying information on a period, an offset, and a subframe to be used of a radio resource allocated to a terminal group consisting of at least one terminal sharing a characteristic, and using the same, configuring subframe allocation information for each terminal group; And And transmitting the configured subframe allocation information to at least one terminal. The method according to claim 10, The information about the subframe to be used, And a number of the first subframe indicated by each component, which is allocation information for each terminal group, and the number of subframes continuously used. The method according to claim 11, The first subframe indicated by each configuration is And calculating at least one of a number of subframes constituting one frame, a frame index, a subframe index, and a period of a corresponding configuration. The method according to claim 10, The information about the subframe to be used, And bitmap information for a subframe available within at least one frame of one period. The method according to claim 13, The number of bits constituting the bitmap is calculated by multiplying the number of frames indicated by the bitmap by the number of subframes available in one frame. The method according to claim 10, The terminal group consisting of at least one terminal sharing the characteristic, And a terminal group receiving a nominal subframe for MBMS, an LTE-Advanced terminal group, and a terminal group receiving substantially MBMS data.

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