KR20080030905A - Method for controlling group in the mobile communication system - Google Patents

Abstract

A method for controlling a group in a mobile communication system is provided to reduce scheduling overhead for the transmission of a small amount of packet data through group scheduling and share frequency resources allocated to a specific group with other groups or with a UE flexibly scheduled, thereby efficiently using the frequency resources. A method for controlling a group in a mobile communication system comprises the following steps of: receiving a group control signal including TIB(Transmitting Indicator Bit) which indicates whether data is transmitted to each UE(User Equipment)(UE2,UE3,UE7) included in a corresponding group; and acquiring information about a first RB(Resource Block) allocated to transmit data through the TIB when the data is transmitted in correspondence to a TTI(Transmitting Time Interval) at which the group control signal is transmitted according to the TIB, and receiving the data according to the information.

Description

Method for controlling group in the mobile communication system

1 is a diagram for describing a time-frequency resource block.

2 is a diagram for describing a method of allocating a TIB to a terminal according to one embodiment of the present invention.

3 is a view for explaining an embodiment of the present invention.

4 is a diagram for explaining another embodiment of the present invention.

5 is a diagram for explaining another embodiment of the present invention.

6 is a view for explaining still another embodiment of the present invention.

7 is a view for explaining still another embodiment of the present invention.

8 is a view for explaining still another embodiment of the present invention.

9 is a view for explaining still another embodiment of the present invention.

10 is a diagram for explaining another embodiment of the present invention.

11 is a diagram for explaining another embodiment of the present invention in uplink transmission.

12 is a diagram for explaining another embodiment of the present invention in uplink transmission.

FIG. 13 is a diagram for explaining another embodiment of the present invention in uplink transmission. FIG.

The present invention relates to a mobile communication system and more particularly to a group control in a mobile communication system.

In a mobile communication system, each base station transmits and receives data to and from a plurality of terminals through a wireless channel environment in one cell / sector. In a system operating in a multicarrier and the like, the base station receives packet traffic from the wired Internet network and transmits the received packet traffic to each terminal using a predetermined communication scheme. In this case, the downlink scheduling determines which base station transmits data to which terminal at which timing in which frequency region. In addition, by using a predetermined form of communication method, the data transmitted from the terminal is received and demodulated to transmit packet traffic to the wired Internet network. Uplink scheduling determines whether a base station can transmit uplink data to which terminal using which frequency band at which timing. In general, a terminal having a good channel state is scheduled to transmit and receive data using more time and more frequency resources.

1 is a diagram for describing a time-frequency resource block. Resources for communication in a system operating in multiple carriers and the like can be divided into time and frequency domains. This resource may be defined as a resource block, which consists of any N subcarriers and any M sub-frames or a predetermined time unit. In this case, N and M may be 1. In FIG. 1, one rectangle means one resource block, and one resource block includes several subcarriers on one axis and a predetermined time unit on another axis. In the downlink, the base station selects a terminal according to a predetermined scheduling rule and allocates one or more resource blocks to the selected terminal, and the base station transmits data using the resource block assigned to the terminal. In the uplink, the base station selects a terminal and allocates one or more resource blocks to the selected terminal according to a predetermined scheduling rule. The terminal receives scheduling information indicating that a certain resource block has been allocated from the base station and transmits uplink data using the allocated resource.

In the downlink scheduling scheme, the base station selects a time-frequency resource block having a good channel state based on a downlink channel quality (CQI) reported from the terminal and transmits data using the same. By using a time-frequency resource block with good channel conditions, more data can be sent while using a limited resource block, thereby increasing the overall data transmission capacity of the system. Similarly, in the uplink scheduling method, the base station scheduler may select a time-frequency resource block having a good channel state of the uplink by measuring a reception state of a pilot signal (or a reference signal) transmitted from the terminal, and select the selected resource block. By allocating to the terminal, the terminal transmits data on the uplink using the allocated resource.

In the fast scheduling scheme, a scheduler selects a terminal to which a corresponding resource is allocated in consideration of a channel state of a unit resource defined by unit time and unit frequency in consideration of a change in channel state due to fast fading, and uses the corresponding terminal. To transmit and receive data with the terminal. In such a fast scheduling scheme, since a terminal to be allocated a specific frequency resource is changed every unit time, the terminal should be notified of which frequency resource is allocated to each unit time through a control channel so that the terminal may transmit and receive data. The information transmitted through the control channel includes a list of terminals to receive data through the downlink, a list of terminals to transmit data through the uplink, and positions of time-frequency resources allocated to each terminal on the list. And the number, and the transmission format for the method of modulating and coding the data to be received or transmitted.

One of the points to be aware of when transmitting various information through the control channel as described above is the size of the control channel information. For example, in the 3GPP LTE system, when the entire system band is set to 10 MHz, information of the control channel is estimated to be about 40 to 60 bits per terminal scheduled. In this case, if the amount of data transmitted at one time is more than thousands of bits, the overhead of the control channel of 40-50 bits is not very large.However, when the amount of data transmitted at one time is less than several hundred bits, Overhead is burdensome.

In addition, when a small amount of data is generated in a system using multiple subcarriers, for example, a system in which time-frequency resources are allocated by fast scheduling in OFDM / OFDMA or SC-FDMA, for example, as in a voice service, The overhead of the control channel is burdened by a terminal periodically generating small data packets to be transmitted or a terminal frequently generating small data packets.

An example of representative service is voice in voice call service using 7.95kbps Adaptive Multi-Rate (AMR) codec technology, which improves the overall sound quality by adjusting the bit for voice compression and the bit for channel coding according to the error degree. Data is generated in a small amount of data packets of about 160 bits every 20msec. If a control channel of 40-50 bits is to be used to transmit such a voice packet, the control channel information of the transmission data becomes large, which impairs system capacity and performance.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention is to provide an efficient resource allocation scheme and control signal structure.

The present invention can efficiently utilize frequency resources by reducing scheduling overhead for small packet data transmission through group scheduling and sharing resources allocated to a specific group with other groups or with fluidly scheduled terminals within a transmission unit. Make sure In order to support this, a group control signal is defined, and predetermined information about data transmission of the terminals included in the corresponding group is collectively communicated through the group control signal so that the terminals can efficiently use resources. To be able.

In one aspect of the present invention, a method for transmitting a group signal in a mobile communication system includes a group control signal including information indicating whether data is transmitted for each terminal included in a corresponding group. Receiving a control signal and when the data is transmitted at a timing corresponding to the transmission time interval (TTI) in which the group control signal is transmitted according to the TIB, the data is allocated for the data transmission through the TIB Obtaining information on the first resource block (RB), and receiving data according to the information.

In another aspect of the present invention, a group signal transmission method in a mobile communication system includes a group including information indicating whether a resource for transmitting data is allocated to each terminal included in a corresponding group (Transmitting Indicator Bit: TIB). Receiving a group control signal and transmitting data through the TIB when resources are allocated at a timing corresponding to a transmitting time interval (TTI) in which the group control signal is transmitted according to the TIB. Acquiring information about a first resource block (RB) allocated for the terminal and transmitting data according to the information.

Information indicating whether a resource for transmitting the data has been allocated (Transmitting Indicator Bit: TIB) is abbreviated as TIB for convenience of description below, but is not limited to the term 'TIB' in the group control signal If the information is included to indicate whether a resource for transmitting specific information, for example, data or the like is allocated to the UE belonging to the group, all of the above will be applicable.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of preferred embodiments related to the above objects, structures, and other features of the present invention will be described in detail with reference to the accompanying drawings. The detailed description, which will be given below with reference to the accompanying drawings, is intended to explain exemplary embodiments of the present invention, rather than to represent the only embodiments in which the present invention may be practiced.

A case where one embodiment of the present invention is applied to downlink transmission will be described below.

Scheduling for downlink transmission and notifying scheduling information to a terminal through a control channel can receive the downlink data. There are a plurality of terminals to which a small amount of data is transmitted. The terminals may transmit a control signal in common because some of the services are the same or similar. Accordingly, the present invention divides some terminals into one or more terminal groups and transmits a group control signal to the terminals belonging to each group.

When the terminal requests a service or requests data transmission and reception before transmitting the group control signal, the terminal determines which group the terminal belongs to in consideration of the location, service, etc. of the terminal, and determines which group the terminal belongs to. It tells you if you belong. An example of what can be considered when designating a group to which the terminal belongs will be described. The transmission power for the common signal transmitted to the same group as the group control signal is appropriately selected in consideration of the channel situation so that the UE belonging to the group can receive with a low error probability. To this end, it is preferable to designate a group such that terminals having similar geometry by distance and location from a base station and a moving speed of the terminal belong to the same group.

When a plurality of group control signals are transmitted at a specific transmission time, each group control signal may be transmitted by performing independent encoding. That is, although the group control channel signal for the plurality of groups may be encoded as a group control signal as a whole, encoding may be performed independently for each group control signal. Independently encoding the group control signal as described above, when the power is allocated to the encoded signal, it is possible to allocate the power in accordance with the characteristics of each group has an advantageous effect. In addition, coding methods may be independently determined in consideration of features of each group, for example, features of a terminal included in a group, a service provided, and the like, and may be encoded by the determined coding method. This is the same as the UE-dedicated dynamic scheduling control signal.

There may be a plurality of groups in the system, each group may be assigned a corresponding ID, and each group may be divided by the assigned group ID. That is, when a plurality of group control signals are transmitted at a specific transmission time, the terminal may check whether the group ID is a group control signal for the group to which the terminal belongs by checking the group ID.

In addition, the terminals belonging to the group know in advance which frequency resource the group control signal is transmitted using at which timing, and the group control signal is transmitted through a time-frequency resource known to the terminal in advance, May receive a group control signal for the group to which they belong. In addition, the UE knows the transmission format such as the coding and modulation scheme used for the group control signal as well as the timing and transmission resources at which the group control signal is transmitted, and the group is coded and modulated by the known transmission format. The control signal can be received and decoded. That is, the group control signal is transmitted to the terminals belonging to the group using frequency resources determined in a coding and modulation scheme determined in a known time domain, so that the terminals can receive and decode control information for the group.

The group control signal includes identifier information for identifying the group, information for resolving a transmission error, and information for determining whether data is transmitted to each terminal belonging to the group. Table 1 shows an example of a message format for the group control signal.

TIB 1 TIB 2 TIB 3 TIB 4 TIB 5 TIB 6 TIB 7 reserved Group ID + CRC

The message for the group control signal is configured to include at least one TIB (Transmitting Indicator Bit), a group ID (group ID), and Cyclic Redundancy Checking (CRC) information for checking whether the group ID is in error.

The group ID is identifier information for identifying a group. The terminal may check whether the group ID is a control signal for the group to which the terminal belongs. The group ID may be accompanied by CRC information for checking whether the group ID is in an error state so that a terminal not belonging to a group cannot demodulate the group control signal or recognize that the group ID is not a control channel.

The TIB is bit information indicating whether data is transmitted to each terminal belonging to the group. For example, when 1 bit is allocated to the TIB, when it is set to '0', it means that no data is transmitted to the terminal corresponding to the TIB, and when it is set to '1', it is transmitted. This means that there is data transmitted to the terminal corresponding to the TIB. Each TIB may be allocated not only in one bit but in addition. In addition, each TIB is assigned at least one to each terminal for the terminals belonging to the group. Accordingly, each terminal knows what the TIB is for its own, and checks the corresponding TIB to know whether there is data transmitted to itself within the transmission time interval.

2 is a diagram for describing a method of allocating a TIB to a terminal according to one embodiment of the present invention. When the base station designates that a specific terminal belongs to a specific group, the base station determines which TIB is assigned to which terminal among the at least one TIB of the group control signal and informs the terminal. Referring to FIG. 2, a case in which seven terminals belong to a specific group will be described. The TIB is allocated to each terminal among the seven terminals. The group may allocate at least seven TIBs and allocate a first TIB to a first terminal and a second TIB to a second terminal. All the TIBs are allocated to the seventh terminal in the same manner as above. In this case, one TIB is allocated to each terminal. However, the base station may vary the number of TIBs to be allocated when the service types of terminals belonging to a group are different, for example, according to characteristics of each terminal. This is related to the number of transport resource blocks described later. As described above with reference to FIG. 1, the resource block means a unit set for allocating and using a transmission resource. The size of the resource block may be fixed and defined as one, but in some cases, resource blocks of various sizes, such as a first resource block and a second resource block, may be defined.

If the terminal belongs to a group, the base station allocates a TIB for each group control signal and informs the terminal. In addition, the base station informs the terminal at which timing the group control signal of the corresponding group is transmitted, what period the group control signal is transmitted, and which frequency resource is transmitted. In addition, the corresponding group may inform the information about the transport resource block through the TIB. That is, the size of the data transmission resource block allocated per TIB of the group is designated and notified to the terminal. Upon receiving this, the terminal can know through which transmission resource block data is transmitted through the TIB information. A method of identifying the location of the resource block through the TIB information will be described in detail with reference to FIG. 3.

Assuming that the UEs belonging to a specific group are UEs having the same or similar geometry, it can be assumed that they transmit the same amount of data using the same modulation and coding scheme. However, it is not mandatory that terminals belonging to a specific group all use the same modulation and coding technique. However, it should be assumed that the size of the resource blocks allocated to the TIBs allocated to the UEs belonging to the same group is constant. Hereinafter, the size and location of the RBs can be relatively simply known through the received TIB information. Accordingly, it is preferable that a terminal allocated with a TIB in the same group has the same resource block size allocated to one TIB.

In addition, as described above, when the service types provided to terminals belonging to a specific group are different, a plurality of transmission indicator bits (TIBs) are allocated to a specific terminal to transmit a plurality of times as much data as a terminal to which one TIB is allocated. Resource blocks can be used to transmit data and to know this through group control signals. In this case, the modulation and coding scheme used by the UE may be set differently according to the number of TIBs to be allocated. When one terminal is assigned a plurality of TIBs, only a part of the allocated TIBs may be operated in a fluid manner so that the payload size of transmission data may be changed every time group scheduling is performed.

3 is a view for explaining an embodiment of the present invention. Hereinafter, a method of determining a resource block in which data is received by a terminal according to TIB information allocated to the terminal will be described with reference to FIG. 3.

FIG. 3 (a) is a diagram illustrating frequency allocation per unit time, i.e., for one transmitting time interval (TTI). Referring to FIG. 3 (a), it is possible to know frequency resources used for data transmitted to each terminal for a corresponding TTI. In the present embodiment, it is assumed that two resource blocks are set to be allocated to one TIB. That is, in the terminal allocated to one TIB, data transmitted to the terminal is transmitted using two transmission resource blocks. 3B shows TIB information included in the group control signal. From the left bit information, TIB information about the first to eighth terminals belonging to the group can be known. As described above, it is assumed that when one bit is used as the TIB and is set to '0', no data is transmitted, and when it is set to '1', it means that there is data to be transmitted. Accordingly, it can be seen that data is transmitted to the corresponding TTI to the second terminal, the third terminal, and the seventh terminal through FIG. 3 (b).

Hereinafter, an example of a method of determining, by using a certain resource block, data transmitted to the terminal is described. As described above, the group control signal is transmitted for downlink data transmission, but the group control signal informs the terminals belonging to the group to the corresponding TTI whether the data is being transmitted to the terminal through the TIB. For example, the bit value of the i-th TIB, that is, the i-th TIB, is denoted as TIB (i). Therefore, when TIB (i) = 1, it means that data is being transmitted to the terminal to which the i-th TIB is allocated, as described above. In addition, the position of the resource block to be transmitted data can be seen how many data is transmitted to the terminal prior to sleep according to the TIB order assigned through the TIB bit map for the TIB transmitted through the group control signal, each terminal Since it knows how many resource blocks are allocated per TIB, it is possible to know from which resource block data to which UE is transmitted using from which resource block. That is, referring to the seventh terminal of FIG. 3, since the TIB value of the seventh terminal is set to '1', it can be seen that data is transmitted. In addition, since the TIB value for the two terminals is set to '1' prior to the seventh terminal, 2 * 2_RB next resource blocks, that is, five resource blocks to two resource blocks are used for the seventh terminal. It can be seen that the data is transmitted. This is represented by Equation 1.

According to Equation 1, it can be seen that data is transmitted using N_RB resource blocks in (L * N_RB) + first resource block among the allocated data transmission resource blocks. L indicates the number of terminals through which data is transmitted before the corresponding terminal. The N_RB is the size of the data transmission resource block allocated per TIB of the group. And, X means each resource block assigned to the terminal. That is, the X-th resource block, that is, (L * N_RB) + 1st resource block, (L * N_RB) + 2nd resource block, ..., (L * N_RB) means that data is transmitted to the UE through resource blocks up to (N * RB) + N_RB resource block.

If up to N TIBs are transmitted in a particular group, there are potentially N * N_RBs of data transmission resource blocks assigned to that group, but if only M of N TIBs are active when scheduling for a particular TTI, that group in that TTI The total size of the data resource blocks used by the terminals belonging to the M is N * N_RB. Therefore, resource blocks that are not used by a group in the corresponding TTI can be efficiently allocated to dynamic scheduled UEs or used in other groups, thereby efficiently utilizing frequency resources.

4 is a diagram for explaining another embodiment of the present invention. Hereinafter, a case in which resource blocks for two groups are allocated to one TTI and the two group control signals are transmitted will be described with reference to FIG. 4.

Referring to FIG. 4, an example in which resource blocks for transmitting two group control signals is divided and transmitted in resource blocks for transmitting data and frequency division multiflexing (FDM). The group control signal may be transmitted by being divided into the data and a time division multiflexing (TDM) scheme or a hybrid of the two schemes (Hybrid scheme).

An embodiment of the present invention will be described in detail centering on data transmitted at a timing of TTI = 0. During the TTI, group control signals for the first group and the second group are transmitted, and data transmitted to terminals belonging to each group are transmitted. In the case of the first group, 12 TIBs are transmitted for the first group, and the size of the data transmission resource block allocated to each TIB is 1 (N_RB = 1). In the case of the second group, six TIBs are transmitted for the second group, and the size of the data transmission resource block allocated to each TIB is 3 (N_RB = 3). That is, there are potentially 12 (1 * 12) data resource blocks for the first group, and potentially 18 (3 * 6) data resource blocks for the second group. As can be seen with reference to FIG. 4, data resource blocks potentially allocated to the two groups are partially overlapped at the middle of the entire resource blocks. Therefore, when using each potentially allocated resource block, it is preferable to use resource blocks that do not overlap with other groups and resource blocks as much as possible. For example, in the case of the first group to which potential resource blocks are allocated on the left side as shown in FIG. 4, when the TIB is activated and needs to be used for data transmission, the first group may be used from the left among the potential resource blocks allocated to the group. do. It can be seen that data is transmitted to the first terminal, the third terminal, the fourth terminal, and the sixth terminal during the corresponding TTI through the TIB bitmap for the first group. When data is allocated according to the above method, data for the first terminal of the first group is transmitted through the resource block corresponding to the leftmost resource block in the drawing among the resource blocks allocated to the first group. In addition, in the case of the third terminal of the first group, since the TIB 3 is set to '1', data is transmitted, and the data for the terminal is transmitted through the right-right resource block of the first terminal. In the case of the fourth terminal of the first group, it can be seen that data is transmitted through the right resource block of the third terminal. Finally, in case of the sixth terminal, it can be seen that data is transmitted through the right resource block of the resource block for the fourth terminal.

In the case of the second group, data is transmitted to each terminal using the right-most resource block in the drawing so as to avoid collision with the use of the resource block for the first group. That is, it can be seen that data is transmitted to the third terminal and the fifth terminal of the second group through the TIB bit map for the second group. The data transmitted to the third terminal of the second group is transmitted using three rightmost resource blocks, and the data transmitted to the fifth terminal includes three left resource blocks of resource blocks allocated to the third terminal. Is sent using. Through the method of allocating resource blocks per group as described above, limited resource blocks can be used more efficiently. In addition, when there are resource blocks remaining even after allocating resource blocks for data to be transmitted to the terminals belonging to the two groups, they may be allocated to other terminals, thereby enabling more efficient resource use. That is, as an example, the remaining resource blocks may be allocated for data transmission that is not a target of continuous scheduling for a specific terminal, or may be allocated for data transmission for a terminal to which resources are dynamically allocated.

5 is a diagram for explaining another embodiment of the present invention. Hereinafter, a case in which resource blocks for three groups are allocated to one TTI and the three group control signals are transmitted will be described with reference to FIG. 5. In this case, an embodiment of the present invention will be described in detail centering on data transmitted at a timing of TTI = 0.

Three group control signals are transmitted during one TTI, and resource blocks for the corresponding TTIs are allocated for data transmitted to terminals belonging to each group, and data is transmitted. In the case of the first group, 12 (1 * 12) resource blocks are potentially allocated to transmit data through one resource block for up to 12 terminals from the leftmost resource block. In the case of the second group, 15 (3 * 5) resource blocks are potentially allocated so that data can be transmitted through three resource blocks for up to five terminals from the rightmost resource block. Finally, in the case of the third group, 16 (2 * 8) resource blocks are potentially allocated so that data can be transmitted through two resource blocks for up to 8 terminals in the middle on the frequency axis.

When allocating resource blocks in each group, in order to avoid collision with other groups as much as possible, the leftmost resource block is used in the first group, and the rightmost resource block is used in the second group. In this case, it is preferable to start with the intermediate resource block and use it step by step from side to side.

Referring to FIG. 5, in the case of the first group, data is transmitted to the first terminal, the third terminal, and the fourth terminal through the TIB bit map, and data is transmitted using the leftmost resource block one by one. In the case of the second group, it can be seen that data is transmitted to the third terminal and the fifth terminal through the TIB bit map, and data is transmitted using three pieces sequentially from the rightmost resource block. Finally, it can be seen that data is transmitted to the first terminal, the fourth terminal, and the seventh terminal through the TIB bit map. The data for the first terminal is allocated to be transmitted using two resource blocks corresponding to the middle. Data for the fourth terminal uses two left resource blocks of the transport resource block corresponding to the first terminal, data for the seventh terminal is two right resource blocks of the transport resource block corresponding to the first terminal Is sent using. Even in the case of allocating resource blocks for each group in the same manner as above, resource blocks may be allocated to each group and the remaining resource blocks may be allocated for data transmission that is not subject to continuous scheduling for a specific terminal, This may be allocated for data transmission for the allocated terminal.

6 is a view for explaining still another embodiment of the present invention. Hereinafter, an example of a diversity method of a group control signal will be described with reference to FIG. 6.

When assuming that a group control signal transmission method is used for transmitting small packet data, scheduling according to a channel situation, that is, channel dependent scheduling, such as when using a flexible scheduling method, There is difficulty. Therefore, in transmitting the packet data, it is very effective to obtain a gain through channel diversity to prevent a transmission error or to increase a transmission success rate. Therefore, as shown in FIGS. 4 and 5, it is more effective that data for each terminal is distributed and allocated in frequency than the data transmitted to each terminal locally in resource block units. That is, in the physical mapping structure on the actual frequency, as shown in FIG. 6, it is preferable that the data resource blocks are not physically allocated locally on the frequency, but distribute the resource blocks corresponding to each group. In the case of distributing the resource blocks allocated to the respective terminals, they may be distributed in subcarrier units or in a subcarrier aggregation unit smaller than the resource blocks. The unit smaller than the resource block is called a second resource block because it is different in size from the resource block used above. For example, as shown in FIG. 6, when data is transmitted from the corresponding group to M terminals in the corresponding TTI, resource blocks for transmitting a total of M * N_RB groups are distributed in subcarrier units so that data for one terminal is transmitted. The resources for transmission are not all adjacent resources but randomly mixed with resources for data transmission to other terminals, that is, they can be distributed and transmitted.

A second resource block unit is set so that one resource block is divided into four resource blocks on a frequency, and data for each terminal is allocated to the set second resource block. That is, a total of four resource blocks are divided into four second resource block units and allocated to transmit data for the first terminal, the third terminal, the fourth terminal, and the sixth terminal. That is, although the method of FIG. 4 is allocated such that data for one terminal is transmitted to one resource block, according to the method of FIG. 6, data for four terminals are divided into frequency axes in one resource block. Is allocated to be sent. When transmitting the data, the information on the distribution may be transmitted together so that each terminal knows the resource to receive the data.

7 is a view for explaining still another embodiment of the present invention. Hereinafter, another example of the diversity method of the group control signal will be described with reference to FIG. 7.

Each transmission resource is divided into at least two time units so that data of each terminal can be distributed and transmitted. As shown in FIG. 4, rather than allocating one resource block for data transmitted to one terminal, each terminal is divided on the basis of each second resource block divided after dividing by a time axis for one first resource block. Allocate data for That is, as shown in FIG. 7, each of the first resource blocks is divided into two parts on the time axis to set a second resource block unit. When allocating data for the UEs belonging to the first group, the UE allocates data in units of the second set resource block. For example, data for the first terminal and the fourth terminal are respectively transmitted to the two leftmost second resource blocks, and data for the third terminal and the sixth terminal are sequentially transmitted to the next two second resource blocks. Is assigned. Then, the second two resource blocks are allocated to transmit data for the first terminal and the fourth terminal again, but the data for the fourth terminal is first changed by changing the time axis with the leftmost second resource block. Assign to send. In the case of the last allocation, the data for the third terminal and the sixth terminal are allocated to be transmitted, but the data for the sixth terminal is allocated to be transmitted first. When transmitting the data, information on the distribution may be transmitted together so that each terminal knows the resource to receive the data.

Due to a change in terminal characteristics represented by geometry, it may be advantageous to change the group to which the terminal belongs to another group. In this case, in order to facilitate the group change process, a method of designating a specific terminal to belong to at least two groups may be used instead of specifying to belong to only one group. In addition, even in the case of flexible scheduling in a modulation and coding scheme, the modulation and coding scheme may be easily changed by designating that the modulation and coding scheme belong to different groups. When one terminal belongs to at least two or more groups as described above, it will receive a group control signal for each group to which the terminal belongs. That is, when belonging to two groups, at least two group control signals will be received.

In addition, in the case of HARQ retransmission, a method of hopping the location of the data resource block allocated to each group may be used for every TTI in order to obtain a diversity gain for the HARQ retransmission.

Data is transmitted according to scheduling, but data may be lost or damaged during the data transmission process. In this case, an error control method may include an automatic repeat request (ARQ) method and a more advanced hybrid ARQ (HARQ) method. Error checking by the above two methods is performed in units of frames. Data transmitted during the frame unit is referred to as a frame hereinafter. The ARQ method waits for an ACK signal to be transmitted after one frame transmission, and transmits an ACK signal when the receiving side properly receives the frame. However, when an error occurs in the frame, a NAK (negative-ACK) message is sent, and the received error frame deletes the information from the receiving buffer. When the transmitting side receives the ACK signal, the frame is transmitted after that, but when the NAK message is received, the frame is retransmitted. Unlike the ARQ method, the HARQ method transmits a NAK signal from the receiving side to the transmitting side when the received frame cannot be demodulated, but stores the received frame in the buffer for a predetermined time without deleting the received frame from the buffer. Therefore, when the frame is retransmitted, the reception success rate is increased by combining the previously received frame and the retransmitted frame. Recently, the HARQ scheme is more widely used than the basic ARQ scheme.

There are several types of HARQ schemes. According to the timing of retransmission, it may be divided into synchronous HARQ and asynchronous HARQ. In the synchronous HARQ scheme, when the initial transmission fails, subsequent retransmission is performed at a timing determined by the system. For example, assuming that the timing of retransmission is set to occur every fourth time unit after the initial transmission failure, the timing for retransmission between the base station and the terminal is already promised. There is no need to inform. That is, if the data transmission side receives the NAK signal, the frame is retransmitted every fourth time until the ACK signal is received. On the other hand, in the asynchronous HARQ scheme, information on retransmission timing is newly scheduled or known through additional signal transmission. That is, the timing at which retransmission is performed for a previously failed frame varies depending on various factors such as channel conditions.

In addition, the HARQ scheme may be divided into a channel-adaptive type and a channel-non-adaptive type depending on whether the channel state is reflected when allocating resources used for retransmission. The channel-adaptive HARQ scheme is a scheme in which a resource block used for retransmission, an MCS level that defines a modulation scheme or a coding scheme of a frame, and the like are determined as initially determined. And, the channel adaptive HARQ scheme is a scheme in which they vary depending on the state of the channel. For example, in the case of channel-adaptive HARQ scheme, the transmitting side transmits data using eight resource blocks during initial transmission, and then uses eight resource blocks in the same way regardless of the channel state during retransmission. Resend. On the other hand, in the case of the channel adaptive HARQ scheme, although transmission is initially performed using eight, it may be retransmitted using a resource block larger or smaller than eight depending on the channel state.

According to this classification, a combination of four HARQs can be achieved. However, the HARQ scheme mainly used according to the characteristics of each scheme may be an asynchronous channel adaptive HARQ scheme and a synchronous channel non-adaptive scheme. In general, in the case of the asynchronous channel adaptive HARQ scheme, the retransmission efficiency can be maximized by adaptively varying the retransmission timing and the amount of resources used according to the channel state. However, since the overhead is large, it is generally considered for the uplink. It doesn't work. On the other hand, the synchronous channel non-adaptive HARQ scheme has the advantage that there is little overhead for this because the timing and resource allocation for the retransmission is promised in the system, but the disadvantage is that the retransmission efficiency is very low when used in a channel state with a high change have.

8 is a view for explaining still another embodiment of the present invention. Hereinafter, a method of using the group scheduling method together with the HARQ retransmission method will be described with reference to FIG. 8. In particular, this case assumes that new packet data is generated periodically.

The group scheduling method described above, that is, a method of transmitting a group control signal, may be used to transmit and retransmit a newly generated packet periodically in association with an HARQ retransmission operation.

It is assumed that the period in which the new packet data occurs is 12 TTI. When new packet data to be transmitted every 12 TTI occurs, if the TIB in the group control signal transmitted first at the timing corresponding to the boundary of 12 TTI is activated, for example, set to a value of '1' This means that data is transmitted, but new data is transmitted. In addition, if the TIB in the group control signal transmitted to the TTI within the period in which the same new data occurs is active, this means that the data is transmitted, which is the data retransmitted for the data. Since the base station notifies the terminal in advance of the period in which the new packet data is transmitted, that is, the timing of the boundary of 12 TTIs, the time point at which the new data is transmitted may be known between the transmitting and receiving terminals.

Referring to FIG. 8, the base station transmits new data together with the group control signal to the terminal (TTI = 0). Since the TIB of the terminal included in the group control signal is set to '1', it means that data is transmitted to the corresponding terminal. In addition, since the data is transmitted at the start timing of a period in which new packet data is transmitted, it can be seen that the data is new packet data. The terminal receiving the data transmits a NAK signal to request the base station to retransmit the data. The base station receiving the NAK signal retransmits the transmitted data together with the group control signal (TTI = 4). In this case, since the TIB for the corresponding UE included in the transmitted group control signal has data retransmitted to the MS, it is also set to '1' and transmitted. The terminal may know that data is transmitted through the activation of the TIB value in the group control signal. In addition, since the new data is not the time to be transmitted, it can be seen that the transmitted data is retransmission data. If the terminal transmits an ACK signal to the base station for the retransmission, the data is no longer transmitted. Therefore, since the data is not transmitted to the terminal until the next new data is transmitted, the TIB value for the terminal is set to '0' and the group control signal is transmitted. After one cycle of transmitting the new packet data ends, when the next cycle starts, new data is transmitted at the start timing of the next cycle, and the TIB in the group control signal transmitted is set to '1' and transmitted (TTI = 12).

That is, when the period in which the new data packet is transmitted is set as described above, it is possible to distinguish whether the data transmitted at a timing is the new data and the data transmitted at a certain timing. Therefore, it is possible to determine whether data is transmitted to the terminal according to whether the TIB value of the corresponding terminal in the group control signal is '1' or '0', and the transmitted data according to the timing at which the group control signal is transmitted. It may be determined whether is new data or retransmitted data. That is, the receiver may determine the information through the TIB in the group control signal without transmitting additional information for distinguishing new data transmission / retransmission.

When new data is transmitted aperiodically, it is difficult to distinguish between new data and retransmitted data by the method described with reference to FIG. 8. Therefore, in order to more clearly distinguish between new data and retransmitted data, when receiving the new data or retransmitted data and receiving an ACK signal indicating that the transmission is successful, the ACK signal is received instead of immediately afterwards. Thereafter, at least one transmission is performed without activating the TIB for the terminal. That is, it is intended to know that new data is transmitted when the TIB value transmitted after at least one TIB that is not activated is set to '1' (when activated). Not activated above may mean that data for the terminal is not transmitted during the corresponding TTI, and for example, may be transmitted by setting the TIB value of the terminal to '0'.

Through the above method, even when new data is transmitted aperiodically, the HARQ retransmission method may be used using the TIB. In this manner, it is also possible to solve the limitation in the time that new packet data can be transmitted when new packet data occurs aperiodically. That is, a new packet is transmitted once every 12 TTIs in advance, so that new packet data can be transmitted at different timings instead of using HARQ retransmission, thereby reducing transmission delay and increasing transmission efficiency. There is.

In another embodiment of the present invention, a new packet indicator bit (NIB) is additionally used to the terminal that generates a small amount of packet data aperiodically in addition to the above-described TIB. Hereinafter, information for indicating that new packet data is abbreviated as NIB for convenience of description, but is not limited to the term 'NIB' as in TIB. In order to indicate that the packet data is new, at least one bit may be additionally used to more effectively use the HARQ retransmission scheme together with the group signaling scheme.

That is, when one bit is used as the NIB, at least one NIB is allocated to terminals included in each group, similarly to the TIB. When the new data packet is transmitted to the terminal, the NIB value is set to '1' and transmitted. If the retransmission data is transmitted or the data is not transmitted, the NIB value may be set to '0'. If the NIB is set to be allocated only when the TIB is activated with '1', the NIB is allocated and transmitted, assuming that the TIB is activated and data is being transmitted. If it is activated as '1' and retransmitted, it can be set as '0' and transmitted. The NIB may be allocated to all terminals belonging to the group or may be allocated only to some terminals.

Table 2 shows an example of a message format for a group control signal when not only the TIB but also the NIB is included in the message for the group control signal.

TIB1 NIB1 TIB2 NIB2 TIB3 NIB3 TIB4 NIB4 TIB5 NIB5 reserved Group ID + CRC

In Table 2, positions of TIBs and NIBs are configured in order of each terminal for each terminal belonging to the group. That is, TIBs and NIBs for the first terminal are sequentially arranged from TIBs and NIBs for the fifth terminal. In addition, as shown in Table 1, a terminal not belonging to a group may not demodulate the group control signal or the control channel may be provided to the terminal with the identifier information of the corresponding group and the CRC information for checking whether the group ID is in error. You can make it aware.

The group control signal according to the message format is determined by the total number of bits transmitted through the group control signaling channel according to a modulation and coding scheme previously known to the UE in the corresponding TTI, and the bits for group ID + CRC are determined from the determined number of bits. If the remaining bits are L bits, the maximum L UEs can be accommodated in the group when only the TIB transmission is considered, and the L / 2 terminals can be accommodated in the group when all the terminals are assigned the TIB and the NIB. .

Table 3 shows another example of the message format for the group control signal when the TIB as well as the NIB are included in the message for the group control signal.

TIB1 TIB2 TIB3 TIB4 TIB5 TIB6 TIB7 reserved NIB5 NIB4 NIB3 NIB2 NIB1 Group ID + CRC

Referring to Table 3, the TIBs of the terminals included in the group are transmitted, and then the NIBs are transmitted. When only some terminals are assigned an NIB, if the message format shown in Table 2 is used, it may be difficult to determine the location of the allocated resource block from the side receiving the group control signal. Therefore, when only some terminals are assigned an NIB, NIBs are allocated separately without being mixed with the TIBs in order not to affect the calculation of the location of the resource block through the number of activated TIBs described above. That is, as shown in Table 3, the NIB can be configured to be allocated from behind. This method avoids the risk of additional confusion of the NIB in determining the location of resource blocks through the TIB.

9 is a view for explaining still another embodiment of the present invention. Hereinafter, a method of using the group scheduling method together with the HARQ retransmission method will be described with reference to FIG. 9. In particular, it is assumed that this case is a case where new packet data occurs aperiodically.

If the TIB in the group control signal is activated, it means that there is data transmitted to the corresponding terminal. If the TIB in the group control signal is not activated, it means that there is no data transmitted. If the NIB in the group control signal is activated, new data is transmitted. If the NIB is not activated, it is assumed that retransmission data is transmitted or that no data is transmitted. In addition, it is assumed that the TIB as well as the NIB are allocated to the corresponding terminal of the present embodiment.

The base station activates both the TIB and NIB in the group control signal to the corresponding terminal (that is, sets the value to '1') and transmits the data with the data (TTI = 0). When the NAK signal is received from the terminal, the transmitted data is retransmitted (TTI = 4). At this time, the TIB value will be activated because there is data to be transmitted when the retransmission is performed, but the NIB value is not activated, so that the TIB value is retransmitted. That is, the terminal receiving the group control signal may know that data is being transmitted to the terminal and the transmitted data is retransmitted data. When the terminal receiving the retransmitted data transmits an ACK and the base station receives it, the transmission of the data is completed. Then, when new data is transmitted to the corresponding terminal again, both TIB and NIB values of the corresponding terminal in the group control signal are activated (that is, set to a value of '1') and transmitted together with the data to the terminal ( TTI = 8). When the ACK signal is received from the terminal for the data, transmission of the data is also completed. If no data is transmitted to the corresponding terminal at the time when the group control signal is transmitted, the TIB and NIB values of the terminal in the group control signal are not activated (that is, set to a value of '0'). ) send. Upon receiving the group control signal, the terminal may know that there is no data transmitted to the terminal.

In setting the NIB value, when the TIB value is set to be assigned and transmitted only when the NIB value is activated, it means that new data is transmitted when the NIB value of the corresponding UE is activated, and when the NIB value is not activated. This may mean that retransmission data is transmitted. In this case, when the TIB value is not activated, the NIB may not be allocated to the corresponding terminal.

10 is a diagram for explaining another embodiment of the present invention. Hereinafter, a method of using the group scheduling method together with the HARQ retransmission method will be described with reference to FIG. 10. In particular, even in this case, it is assumed that new packet data occurs aperiodically.

10 differs in that the toggling method is applied in setting the NIB value compared with the embodiment shown in FIG. The toggling is to transmit the setting value of the information bit in consideration of the previous transmission value and to change the setting value if there is a predetermined change compared to the previous transmission value, and to maintain the previous value if there is no change. It is a way.

In the present embodiment, when the toggling method is described, when the NIB value is set to '0' while transmitting new data and transmitted, the transmitted data is retransmitted in response to a retransmission request or the data is not transmitted. In this case, the NIB value is set to '0' without changing, but when the other data other than retransmission, that is, new data is transmitted, the setting value is changed to '1' and transmitted. That is, the receiving side of the NIB value can be seen that the new data is transmitted when there is a change compared to the previous value, if there is no change, that is, the same as the previous setting value, retransmission data is transmitted or data transmission It can be seen that there is no.

In this case, the NIB may be allocated only when data is transmitted to the terminal according to the TIB value. In this case, when the NIB value changes, the same means that new data is transmitted, but when the same value is transmitted without changing the NIB value, it may mean that retransmission data is transmitted. . In the absence of data transmission, the TIB value is not activated and no NIB is assigned.

Referring to FIG. 10, the base station transmits a group control signal with new data to a specific terminal belonging to the corresponding group, but sets the TIB value of the group control signal to '1' and the NIB value to '0'. (TTI = 0). When the NAK signal is received from the terminal for the transmission, retransmission data is transmitted to the terminal (TTI = 4). At this time, the TIB value in the group control signal transmitted together sets a value of '1' which means that data is transmitted, and the NIB value is set equal to the previous transmission value to indicate that it is retransmission, that is, set to '0' and transmitted. . Upon receiving this, the UE may know that data is transmitted to itself through the TIB value in the group control signal, and may be retransmission data through the same NIB value transmitted as the previous NIB value. In response to this, the terminal transmits an ACK signal to the base station, thereby ending the transmission of the data. The base station transmits new data to the terminal (TTI = 8). At this time, the TIB value in the group control signal transmitted together is set to '1' to indicate that data is transmitted, and the NIB value is set to '1' which is different from the previously transmitted NIB value to indicate that new data is to be transmitted. send. Upon receiving the group control signal, the UE may know that data is transmitted to itself through a TIB value, and may recognize that new data is transmitted through an NIB value different from the previous NIB value. When the base station receives an ACK signal for the data, transmission of the data is completed. Thereafter, in the timing of transmitting the group control signal, if there is no data transmitted to the terminal, the TIB value in the group control signal is set to '0' to transmit the signal. The NIB value may or may not be transmitted according to the configuration on the system. In case of transmission, the same value as the previous value is transmitted. That is, in the case of FIG. 10, the NIB value is set to '1' and transmitted (TTI = 12). Upon receiving this, the UE may know that there is no data transmitted to the TTI.

In the case of using the method described with reference to FIGS. 9 and 10, when a loss occurs on the channel compared to a method of activating the TIB value at least once after receiving an ACK signal indicating that the transmission is successful. Reduce the rate of malfunctions. In addition, since the TIB does not need to be activated more than once for new data transmission, the HARQ retransmission scheme can be used more efficiently.

In addition, using this method, when new packet data occurs aperiodically, new data can be transmitted without limiting the time that new packet data can be transmitted. That is, as shown in FIG. 8, since a new packet is transmitted once every 12 TTIs, it is not necessary to fix the transmission delay, thereby improving transmission efficiency.

In setting the TIB and the NIB, a method of configuring information that can be transmitted through the TIB and the NIB together using at least two bits without setting and configuring the TIB and the NIB separately is also proposed. Can be. Table 4 shows an example of information configuration for transmitting information corresponding to TIB and NIB through two bits.

Infomation bit state 00 No Tx 01 New Tx 10 1 st ReTx (first retransmission) 11 2 st ReTx (en th retransmission)

As can be seen from Table 4, the TIB and NIB is combined to transmit a plurality of bits to the terminals in the group to transmit information on the TIB and NIB and information on retransmission. Referring to Table 4, if two bits of information bits for the corresponding information transmission described above are allocated to each terminal, whether or not there is data transmission is transmitted, whether it is new data transmission or retransmission, and in case of retransmission, first retransmission or second You can tell whether it is retransmission. For example, '00' is set when there is no data transmitted to the terminal, data is transmitted, '01' is set when new data is transmitted, and the remaining information bits are set when the data is retransmitted. send. That is, in the case of the first retransmission, '10' is set, and in the case of the second retransmission, '11' is transmitted.

Table 4 above is just an example, and three or more bits may be allocated and used as corresponding information bits. If three or more bits are allocated, not only the information on the state set in Table 4, but also information on more retransmissions, that is, information on the HARQ Process Index and information on the IR version (IR_version) will be transmitted. The Incremental Redundancy (IR) version refers to information about a preset additional bit. That is, in order to increase the decoding probability, a method of adding a predetermined bit to the previous transmission including the initial transmission may be used for each retransmission. In this case, various versions are preset according to the type or type of the added bits, and the information on the various versions may be information on the IR version. In this case, at least one state will be designated as a state indicating that there is no data transmission.

Although the above description has been made in consideration of downlink transmission, the same concept will be described below by applying the uplink transmission method.

As in the downlink data transmission, the scheduling of radio resources is controlled by the base station in the uplink data transmission. Therefore, since the scheduling is not performed at the transmitting side, the basic operation of uplink scheduling is different from that of downlink scheduling. In downlink transmission, a base station selects a terminal to receive data, transmits scheduling information through a control channel, and simultaneously transmits corresponding downlink data. However, in the uplink, when the base station selects a terminal to transmit data and informs the selected terminal which radio resource to use to transmit data, the terminal transmits data using the resources allocated to the data transmission to the selected terminal. Do this.

It is clear that the uplink and the downlink are different in the above-described points, but both link transmissions have a lot in common in terms of resource management in a system operating in a multi-carrier and similar forms. Therefore, the group scheduling scheme applied to the downlink can be equally applied in terms of resource management even during uplink transmission.

When the UE intends to transmit data through the group scheduling method in both the uplink and the downlink, it should belong to the UE group for the uplink transmission as well as the UE group for the downlink transmission.

The base station selects a terminal for uplink transmission and allocates transmission resources for scheduling. In this case, as in the downlink transmission, a terminal group including at least one terminal is set to transmit a group control signal to inform whether a resource is allocated for data transmission to a terminal belonging to the group, the location of the allocated resource, and the like. . The group control signal may use the same one as in Table 1 above.

That is, the group control signal also includes a transmitting indication bit (TIB) to indicate whether a resource for transmitting data is allocated to the corresponding terminal. The terminal is assigned to belong to a specific group, and at least one of the TIBs assigned to the group is assigned to the terminal belonging to the group. Thereafter, the terminal receives the group control signal and checks its TIB in the group control signal to determine whether a resource has been allocated to transmit data at a corresponding timing.

The UE included in each group receives in advance information on a timing, a period in which a group control signal is transmitted for the group, a position and size of a resource in which the group control signal is transmitted, and a modulation and coding scheme for the group control signal. I know it. Therefore, the group control signal can be received and decoded to confirm the contents.

Upon receiving the group control signal, the terminal checks the TIB information included in the group control signal and transmits the group control signal to the terminal when the TIB assigned to the terminal is activated (for example, is set to '1'). Data can be transmitted at a timing corresponding to the received timing, and the size and location of the resource block allocated to the user can be checked through the configuration of the TIB bit map. Data may be transmitted at a corresponding timing through the identified resource block. The allocation of the TIB in the group control signal and the method of identifying the location of the resource block using the same are the same as described in the downlink transmission.

In case of uplink, HARQ retransmission scheme may be applied to the group scheduling scheme.

11 is a diagram for explaining another embodiment of the present invention in uplink transmission. Referring to FIG. 11, a method of using a group scheduling scheme and a HARQ retransmission scheme together when the UE periodically generates new packet data will be described.

It is assumed that data that the terminal periodically transmits to the base station is generated, and the period in which the new data occurs is 12 TTI. Both the base station and the terminal know that new data is transmitted from the terminal periodically every 12 TTI. Accordingly, the terminal allocates radio resources necessary for data transmission at a timing corresponding to the 12 TTI boundary and transmits the information. At this time, the group control signal is also transmitted. The TIB value included in the group control signal is activated (for example, set to '1') when the resource is allocated to the terminal and transmitted. Upon receiving the group control signal, the terminal may confirm that data transmission is allowed to the terminal and check the location and size of the allocated transmission resource. The terminal transmits data using the identified resource (TTI = 1).

As described above, the base station and the terminal may know that the data transmission for the group control signal transmitted at the timing is for new data. If the next group control signal in the same transmission period (12 TTI) is transmitted and the TIB value in the group control signal is allowed to allow data transmission, i.e., the TIB value is active, the current timing is the timing of transmitting new data. Since both the base station and the terminal knows that this is not the terminal retransmits previously transmitted data to the base station.

That is, in this case, the structure of the group control signaling and the operating method of the TIB are the same as in the case of downlink transmission described with reference to FIG. 8.

In this case, activation of the TIB in the group control signal transmitted first at the boundary time of 12 TTIs means resource allocation for new packet data transmission, and the TIB in the group control signal transmitted at the next group control signal timing in the same transmission period. When is activated, means that the existing transmitted data has not been properly received, so retransmit. That is, in the uplink, HARQ retransmission can be performed using TIB instead of ACK / NAK signal transmission in HARQ operation.

For uplink transmission of a small amount of data that occurs aperiodically, a new indicator bit (NIB) may be additionally used to inform that the group control signal is for new data, similarly to group scheduling for downlink transmission. In addition, since the uplink transmission data is generated aperiodically compared to the periodic transmission, the UE reports to the base station whether the current transmission data is generated through the uplink transmission channel. One example of a message that the terminal can use to request a resource when data to be transmitted to the base station is generated is a resource request message. Hereinafter, the resource request message is called an RR message.

The RR message is a message transmitted to inform the base station when there is data to be transmitted through the uplink channel. The RR message can be configured using a small number of bits (for example, 1 bit). The data may be transmitted together with a piggy backing method, which is a method of combining and transmitting transmission data and an ACK / NAK signal together through a channel for uplink data transmission. Considering the case where there is no data transmission at that time, an uplink control channel (UL control channel) that is periodically transmitted, typically an uplink pilot channel (UL pilot channel), or channel quality information (CQI) for channel quality information transmission It can also be transmitted through a channel.

12 is a diagram for explaining another embodiment of the present invention in uplink transmission. A method of using a group scheduling scheme and a HARQ retransmission scheme together when the terminal generates new packet data aperiodically will be described with reference to FIG. 12.

As above, the TIB value in the group control signal is activated when a resource is allocated to the corresponding terminal, and is not activated when a resource is not allocated to the corresponding terminal. In addition, the NIB value is activated when a resource for requesting new data transmission is allocated to the corresponding terminal, and is not activated for requesting retransmission to the corresponding terminal or when no resource is allocated. Hereinafter, it is assumed that the activated case is set to '1' and the non-activated case is set to '0'.

Before the base station receives the RR message, since the resource is not allocated to the corresponding terminal, the TIB and NIB values in the group control signal are set to '0' and transmitted. In this case, the NIB may be determined to be allocated only when resources for data transmission are allocated, that is, only when the TIB value is set to '1'. In this case, the NIB is not transmitted.

The terminal generates data to transmit and transmits an RR message to the base station (TTI = 1). The base station receiving the RR message allocates resources to the terminal for scheduling and transmits a group control signal with the scheduling information. The base station transmits by setting the value of TIB included in the group control signal to '1' to indicate that the resource for data transmission has been allocated, and the value of the NIB is set to '1' to indicate that the value of the NIB is for new data transmission. To transmit. Upon receiving the group control signal, the terminal confirms that the resources for data transmission are allocated to the user through the TIB in the group control signal, and confirms the location and size of the resources allocated to the user by checking the number of activated TIBs in the group. do. Then, it knows that resources for new data transmission are allocated through the NIB, and transmits new data to the base station using the checked transmission resource (TTI = 5).

When the base station receiving the data requests retransmission, when configuring the group control signal, the base station sets the TIB value to '1' to inform the terminal that the resource for data transmission has been allocated and sets the NIB value to '0'. It is set to indicate that the resource allocation is for retransmission. Upon receiving the group control signal configured as described above, the terminal checks the TIB and the NIB and retransmits the data using the corresponding resource (TTI = 9). In this case, when data to be newly transmitted to the terminal is generated, an RR message for transmitting new data may be transmitted in a piggybacking manner as described above together with the retransmission data (TTI = 9). The base station receiving the retransmitted data and the RR message from the terminal, if the retransmitted data is properly received, the TIB value for the corresponding terminal in the group control signal to request new data transmission again at the next group control signal transmission timing. Is set to '1' and the NIB value is set to '1'. Upon receipt of the same, the terminal checks the group control signal and transmits new data using the corresponding resource (TTI = 13).

FIG. 13 is a diagram for explaining another embodiment of the present invention in uplink transmission. FIG. A method of using a group scheduling scheme and a HARQ retransmission scheme together when the terminal generates new packet data aperiodically will be described with reference to FIG. 13.

The embodiment shown in FIG. 13 differs in that the toggling method is applied in setting the NIB value compared with the embodiment shown in FIG. 12. As described above, when the setting value of the information bit is transmitted in consideration of the previous transmission value, the toggling changes the setting value when there is a predetermined change compared to the previous transmission value, and when there is no change, the previous value. How to keep it.

Referring to FIG. 13, the base station transmits a TIB value of a corresponding terminal in a group control signal as '0' and an NIB value as '1'. Accordingly, it can be seen that the TTI for transmitting the group control signal is not allocated a resource for data transmission to the terminal. The terminal generates new data and transmits an RR message to the base station (TTI = 1). The base station receiving the RR message allocates resources to the terminal and transmits a group control signal. In addition, since the TIB value for the corresponding UE in the group control signal is set to '1' and the NIB value requests new data transmission, the TIB value is set to '0' which is different from the previous transmission value and transmitted. Upon receiving the group control signal configured as described above, the terminal may recognize that resources for data transmission are allocated to the user through the TIB value, and compare the NIB value with a previously transmitted NIB value to perform new data transmission. I can see that it is a request. Therefore, data is transmitted according to the result of confirming the group control signal (TTI = 5).

When the base station receiving the data wants to request retransmission of the data, the base station transmits the group control signal, but transmits by setting the TIB value in the group control signal to '1' and retransmitting. Set to '0' and send. The terminal retransmits the data through the group control signal (TTI = 9). In this case, when the UE wants to transmit new data, the RR message may be transmitted together in a piggybacking manner (TTI = 9).

If it is determined that the retransmitted data is properly received, it allocates resources for new data transmission according to the RR message and transmits the scheduling information and the group control signal. The TIB value in the group control signal is set to '1' to indicate that a resource for data transmission is allocated, and the NIB value is set to '1' different from the previously transmitted NIB value because a resource for new data transmission is allocated. send. Upon receiving this, the terminal checks the TIB value and the NIB value in the group control signal to identify the allocated resource and transmits new data through the resource (TTI = 13).

The present invention can be used to efficiently schedule frequency resources with little overhead for schedule signaling in services where a small number of packets are periodically generated, such as voice services (e.g., VoIP services). In addition, the present invention can be applied to a service type in which a small amount of packets occur aperiodically, such as a signaling message of a TCP ACK or an L2 / L3 layer.

The terms used above may be replaced with others. For example, a base station may be referred to as a base station (BS), a node ratio (Node_B), and the like, and a terminal may be referred to as a mobile station, a user equipment (UE), a terminal, and the like.

Those skilled in the art to which the present invention described above belongs will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention is shown by the following claims rather than the above description, and it is to be construed that all changes or modifications derived from the meaning and scope of the claims and the same concept are included in the scope of the present invention. will be.

According to the present invention, there is an effect that the frequency resources can be used more efficiently through the group control signal. In addition, the group scheduling method can be used more effectively by applying the HARQ retransmission method together.

Claims (35)

Receiving a group control signal including information indicating whether data is transmitted for each UE included in the corresponding group; And When data is transmitted at a timing corresponding to a transmission time interval (TTI) in which the group control signal is transmitted according to the TIB, a first resource block allocated for the data transmission through the TIB. Acquiring information about RB) and receiving data according to the information Group signal transmission method in a mobile communication system comprising a. The method of claim 1, The group control signal may further include information for identifying a group (Grouup ID) and information for solving a transmission error. The method of claim 1, Information necessary for receiving the group control signal, information on a size of a first resource block allocated to one TIB for the group, and information on at least one TIB assigned to a corresponding terminal among a plurality of TIBs assigned to the group The method of claim 1, further comprising receiving a group signal in a mobile communication system. The method of claim 4, wherein And information necessary for receiving the group control signal is information on a time / frequency resource to which the group control signal is transmitted. The method of claim 1, And assigning a transmission resource corresponding to the one TTI to be used by at least two groups. The method of claim 5, wherein And a group control signal for each group assigned the transmission resource for the one TTI is transmitted during the corresponding TTI. The method of claim 5, wherein When allocating at least one first resource block to a terminal included in each group, group signal transmission method according to a predetermined rule according to a location of transmission resources allocated to each group. . The method of claim 5, wherein A group in a mobile communication system, wherein at least one first resource block is allocated to a terminal included in each group for use in a transmission resource shared among other groups among the transmission resources allocated to each group. Signal transmission method. The method of claim 1, And some of the transmission resources for the corresponding TTI allocated to the group are shared with at least one or more other groups or with a terminal that is flexibly scheduled. The method of claim 1, When allocating at least one or more first resource blocks to a terminal included in each group, group signal transmission method in a mobile communication system, characterized in that distributed allocation in units of a second resource block smaller than the first resource block. The method of claim 10, The distributed allocation method may include one of frequency division multiplexing (FDM), time division multiplexing (TDM), and time / frequency hybrid multiplexing (Hybrid Division Multiplexing). Group signal transmission method in a mobile communication system. The method of claim 1, If new data is sent periodically, Mobile communication characterized in that the activated TIB in the group control signal transmitted at the timing when the new data is transmitted indicates that new data is transmitted, and the activated TIB transmitted at other timings indicates that the retransmitted data is transmitted. Group signal transmission method in the system. The method of claim 1, And transmitting at least one group control signal including an TIB which is not activated and transmitting an ACK signal for the data reception. The method of claim 1, If new data is sent aperiodically, The group control signal further includes information indicating that new data is transmitted to a corresponding terminal belonging to the group (New Indicator Bit: NIB). The method of claim 14, The NIB value is set to a value different from the previous transmission value when new data is transmitted, and is set to the same value as the previous transmission value when retransmission data is transmitted. . The method of claim 1, And at least two or more bits are allocated to the TIB, so that the TIB further indicates at least one of information about new data transmitted and retransmission. Receiving a group control signal including information indicating whether a resource for transmitting data has been allocated for each UE included in the corresponding group; And When a resource is allocated at a timing corresponding to a transmission time interval (TTI) in which the group control signal is transmitted according to the TIB, a first resource block allocated for data transmission through the TIB. Acquiring information about RB) and transmitting data according to the information; Group signal transmission method in a mobile communication system comprising a. The method of claim 17, The group control signal may further include information for identifying a group (Grouup ID) and information for solving a transmission error. The method of claim 17, Information necessary for receiving the group control signal, information on a size of a first resource block allocated to one TIB for the group, and information on at least one TIB assigned to a corresponding terminal among a plurality of TIBs assigned to the group The method of claim 1, further comprising receiving a group signal in a mobile communication system. The method of claim 19, And information necessary for receiving the group control signal is information on a time / frequency resource to which the group control signal is transmitted. The method of claim 17, And assigning a transmission resource corresponding to the one TTI to be used by at least two groups. The method of claim 21, And a group control signal for each group assigned the transmission resource for the one TTI is transmitted during the corresponding TTI. The method of claim 21, When allocating at least one first resource block to a terminal included in each group, group signal transmission method according to a predetermined rule according to a location of transmission resources allocated to each group. . The method of claim 21, A group in a mobile communication system, wherein at least one first resource block is allocated to a terminal included in each group for use in a transmission resource shared among other groups among the transmission resources allocated to each group. Signal transmission method. The method of claim 17, And some of the transmission resources for the corresponding TTI allocated to the group are shared with at least one or more other groups or with a terminal that is flexibly scheduled. The method of claim 17, When allocating at least one first resource block to a terminal included in each group, group signal transmission method in a mobile communication system, characterized in that distributed in the second resource block unit smaller than the first resource block. The method of claim 17, If new data is sent periodically, The activated TIB in the group control signal transmitted at the timing when the new data is transmitted indicates that resources for new data transmission are allocated, and the activated TIB transmitted at other timings is allocated resources for retransmitted data transmission. And a group signal transmission method in a mobile communication system. The method of claim 17, If new data is sent aperiodically, The group control signal further includes information indicating that a resource for new data transmission is allocated to a corresponding terminal belonging to the group (New Indicator Bit: NIB). The method of claim 28, The NIB value is set to a value different from the previous transmission value when requesting new data transmission, and set to the same value as the previous transmission value when requesting retransmission data. Way. The method of claim 28, The method of claim 1, further comprising transmitting a resource request message to transmit new data. The method of claim 17, And transmitting the transmission resource request message and the retransmission data together in a piggybacking manner. Transmitting a group control signal including information indicating whether data is transmitted for each UE included in the corresponding group; And When data is transmitted at a timing corresponding to a transmission time interval (TTI) in which the group control signal is transmitted, a first resource block allocated for the data transmission that a receiver can know through the TIB ( Transmitting the data using a resource block (RB) Group signal transmission method in a mobile communication system comprising a. The method of claim 32, The group control signal may further include information for identifying a group (Grouup ID) and information for solving a transmission error. The method of claim 32, If new data is sent aperiodically, The group control signal further includes information indicating a new indicator bit (NIB) to transmit new data to a corresponding terminal belonging to the group. The method of claim 34, wherein The NIB value is set to a value different from the previous transmission value when transmitting new data, and set to the same value as the previous transmission value when retransmitting data is transmitted. .

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