KR20070023507A - Method for radio resource allocation in multi carrier system - Google Patents

Abstract

The present invention relates to a subcarrier allocation method in a multi-carrier system, and more particularly, to a communication method that can be easily scheduled by efficiently allocating a specific frequency time resource.

The resource allocation method according to the present invention is a communication system for transmitting data in a subframe unit including at least one OFDM symbol, the at least one zone including a plurality of subcarriers adjacent to each other in a frequency domain Constructing a chunk; Assigning the zone chunk to a particular frequency domain according to a distributed allocation method; And allocating the zone chunks to the remaining areas other than the allocated frequency domains according to a distributed allocation method.

OFDM, OFDMA, Scheduling, Chunk, Subcarrier, Zone, Distributed

Description

Radio resource allocation method in multi-carrier system {Method for radio resource allocation in multi carrier system}

1 is a block diagram of a downlink transmission / reception side of OFDMA according to the present invention and the prior art.

FIG. 2 is a diagram illustrating a method of allocating a chunk, which is a basic unit for allocating the subcarriers, to a specific user.

3 is an example of a distributed allocation method and a zone allocation method.

4A is a diagram illustrating an example in which a distributed allocation method and a zone allocation method are applied to a zone chunk according to the first embodiment.

4B is an example of applying the frequency hopping technique to the first embodiment.

5A is a diagram illustrating an example in which a distributed allocation method and a zone allocation method are applied to a zone chunk according to the second embodiment.

5B is an example of applying the frequency hopping technique to the second embodiment.

FIG. 6 is a diagram illustrating distributed chunks (Chunk_D) and zone chunks (Chunk_L) used in an embodiment of the present invention.

FIG. 7 is a diagram showing an example in the case of using a combination of zone chunks and distributed chunks in the FDM scheme according to the third embodiment.

8 is a diagram illustrating an example of a method of multiplexing the above distributed chunks and zone chunks according to the fourth embodiment.

9A to 9B are flowcharts illustrating a method of generating information about resource allocation according to the sixth embodiment.

10A to 10B are flowcharts illustrating a method of receiving information regarding resource allocation and confirming a resource allocated to the same according to the sixth embodiment.

11 is a flowchart illustrating a method of performing resource allocation when using the third embodiment and the sixth embodiment together.

The present invention relates to a subcarrier allocation method in a multi-carrier system, and more particularly, to a communication method that can be easily scheduled by efficiently allocating a specific frequency time resource.

The present invention may be used in an OFDM, DFT-S-OFDM, or OFDMA communication scheme, or may be used in a communication scheme in which data is transmitted by a plurality of subcarriers while maintaining orthogonality between the plurality of subcarriers. Hereinafter, as an example of a communication method of the multi-carrier system, an OFDM scheme, a DFT-S-OFDM (DFT Spreading OFDM) scheme, and an OFDMA scheme will be described.

Hereinafter, orthogonal frequency division multiplexing (OFDM) will be described. The basic principle of OFDM is to divide a high-rate data stream into a large number of low-rate data streams and transmit them simultaneously using multiple carriers. Each of the plurality of carriers is called a subcarrier. Since orthogonality exists between the multiple carriers of the OFDM, the frequency components of the carriers can be detected at the receiving side even if they overlap each other. The high data rate data stream is converted into a plurality of low data rate data streams through a serial to parallel converter, and each subcarrier is included in the parallel data streams. After multiplying, the respective data strings are summed and sent to the receiving side.

A plurality of parallel data streams generated by the serial / parallel transform unit may be transmitted to a plurality of subcarriers by an inverse discrete fourier transform (IDFT), and the IDFT is an inverse fast fourier transform (IFFT). Can be implemented efficiently.

Since the symbol duration of the low carrier subcarrier is increased, relative signal dispersion in time caused by multipath delay spread is reduced. Inter-symbol interference can be reduced by inserting a guard interval longer than the delay spread of the channel between OFDM symbols. In addition, if a part of the OFDM signal is copied to the guard interval and placed at the beginning of the symbol, the OFDM symbol may be cyclically extended to protect the symbol.

Hereinafter, the conventional DFT-S-OFDM scheme will be described. The DFT-S-OFDM scheme is also called Single Carrier-FDMA (SC-FDMA). Conventional SC-FDMA technique is a technique that is mainly applied to uplink. Before generating an OFDM signal, spreading is first applied to a DFT matrix in a frequency domain, and then the result is modulated by a conventional OFDM scheme and transmitted. .

In SC-FDMA, the data symbols s are distributed using a DFT matrix before transmission. N denotes the number of subcarriers transmitting the OFDM signal, Nb denotes the number of subcarriers for any user, F denotes a discrete Fourier transform matrix, or DFT matrix, s denotes a data symbol vector, x Denotes a vector in which data is distributed in the frequency domain, and y denotes an OFDM symbol vector transmitted in the time domain, the SC-FDMA technique may be described as in Equation 1 below.

는, 데이터 심볼(s)을 분산시키기 위해서 사용된 Nb 크기의 DFT 행렬이다. 이렇게 분산된 벡터(x)에 대하여 일정한 부 반송파 할당 기법에 의해 부 반송파 매핑(subcarrier mapping)이 수행되고, IDFT 모듈에 의해 시간영역으로 변환되어 수신 측으로 전송하고자 하는 신호가 얻어진다. 상기 수신 측으로 전송되는 전송신호는 아래 식과 같다. In Equation 1

Is an Nb-sized DFT matrix used to disperse the data symbols s. Subcarrier mapping is performed on the distributed vector x by a constant subcarrier allocation scheme, and a signal to be transmitted to the receiver is obtained by converting to the time domain by the IDFT module. The transmission signal transmitted to the receiving side is as follows.

는 주파수 영역의 신호를 시간 영역의 신호로 변환하기 위해 사용되는 크기 N의 DFT 행렬이다. 상술한 방법에 의해 생성된 신호 y는, 순환 전치(cyclic prefix)가 삽입되어 전송된다. 상술한 방법에 의해 전송 신호를 생성하여 수신 측으로 전송하는 방법을 SC-FDMA 방법이라 한다. DFT 행렬의 크기는 특정한 목적을 위해 다양하게 제어될 수 있다. 예를 들어, 상기 DFT 행렬의 크기가 IDFT의 포인트 수와 동일한 경우 송신 측에서의 PAPR을 감소시킬 수 있다. In Equation 2

Is a DFT matrix of size N that is used to convert a signal in the frequency domain into a signal in the time domain. The signal y generated by the above-described method is transmitted by inserting a cyclic prefix. The method of generating a transmission signal and transmitting it to the receiving side by the above-described method is called an SC-FDMA method. The size of the DFT matrix can be variously controlled for a specific purpose. For example, when the size of the DFT matrix is the same as the number of points of the IDFT, the PAPR at the transmitting side may be reduced.

Hereinafter, orthogonal frequency division multiple access (OFDMA) according to the prior art will be described. OFDMA refers to a multiple access method that realizes multiple accesses by providing each user with a part of subcarriers available in a modulation system using a plurality of orthogonal subcarriers. OFDMA provides each user with a frequency resource called a subcarrier, and each frequency resource is provided to a plurality of users independently of each other so that they do not overlap each other.

Hereinafter, a general OFDMA transceiver will be described. 1 is a block diagram of a downlink transmission / reception side of OFDMA according to the present invention and the prior art.

The transmitter performs constellation mapping on a bit stream for a plurality of users by quadrature phase shift keying (QPSK) or 16 quadrature amplitude modulation (QAM).

That is, the bit stream is mapped to a specific data symbol, and the data symbol is converted into parallel data symbols through an S / P converter. By the serial / parallel conversion operation, the data symbols are converted into parallel symbols equal to the number Nu (n) of subcarriers assigned to each user n. As shown in FIG. 1, the bit stream for user 1 is converted into as many parallel symbols as Nu (1), which is the number of subcarriers allocated to user 1. Subcarriers allocated to each user n may or may not be identical to each other. Accordingly, the data symbols of the respective users may be converted into parallel symbols of the same or unequal size Nu (n).

The data symbols for a specific user converted in parallel are mapped to Nu (n) subcarriers assigned to a specific nth user among all Nc subcarriers, and the remaining Nc- (Nu ( n)) subcarriers are mapped to data symbols of other users. By a symbol to subcarrier mapping module for mapping a symbol to a carrier, zero padding is assigned to a subcarrier to which a user is not assigned. The output of the symbol to subcarrier mapping module is input to an Nc-point inverse fast fourier transform (IFFT) module.

The output of the IFFT module is transmitted after parallel to serial convert is performed after a cyclic prefix is added to reduce inter-symbol interference (ISI).

The OFDMA receiving apparatus according to the prior art is configured in the inverse of the above-described transmitting apparatus. The received data symbol is inputted to a module that performs symbol to subcarrier mapping after the serial / parallel conversion and the Nc-point FFT. The receiving side decodes a symbol of a subcarrier allocated to the receiving side by the mapping module.

Hereinafter, resource allocation according to OFDMA will be described.

In the entire frequency band, specific frequency resources (subcarriers) are assigned only to specific users. Thus, the frequency resource is not shared to other users. More specifically, in allocating frequency resources to users in the implementation of OFDMA, in order for each user to receive them, allocation information of subcarriers must be transmitted from the base station to the terminal. Since transmitting the allocation information for all the subcarriers, respectively, is an excessive amount of information, it is preferable to allocate a plurality of subcarriers in chunks and assign them to users in order to reduce the amount of information.

FIG. 2 is a diagram illustrating a method of allocating a chunk, which is a basic unit for allocating the subcarriers, to a specific user. As shown, the method of allocating the chunks may be divided into a distributed allocation method and a localized allocation method. Each illustrated arrow represents a chunk comprising a plurality of subcarriers.

The distributed allocation of FIG. 2 is a method of allocating chunks over the entire band applied to the communication system to the specific user when all chunks of all the chunks are allocated to the specific user. By allocating chunks across the band to specific users, a gain can be gained by diversity in the frequency domain.

Zone allocation in FIG. 2 is a method of allocating chunks of adjacent bands to a specific user in all frequency bands applied to a communication system.

The prior art assigns chunks to users in a particular way, sending data to multiple users.

3 is an example of a distributed allocation method and a zone allocation method. The total number of chunks is 32, and UE1 represents 10 chunks, UE2 represents 8 chunks, and UE3 represents 14 zone allocation methods and distributed allocation methods. In this case, the chunk indexes are different depending on the two allocation methods. FIG. 3A illustrates a case of distributed allocation in which all of the indices are randomly arranged, and FIG. 3B illustrates case of allocating all indices. When the base station and the terminal share the index according to the allocation method, the allocation information that should be informed by the base station for the normal reception of the terminal, signaling for indicating the available index for each user and whether distributed or zone allocation. That is, the start index 0 and the end index 9 are transmitted to UE1 receiving the data through chunks 0 to 9 and the start index 10 and the end index 17 to UE2 receiving the data through chunks 10 to 17. And transmits the start index 18 and the end index 31 to UE3 receiving the data through chunks 18 to 31. In addition, information is transmitted to each UE as to whether the chunk by zone allocation or the chunk by distributed allocation is used.

The present invention has been proposed to improve the prior art, and an object of the present invention is to provide a communication method that can be easily scheduled by efficiently allocating specific frequency time resources.

Summary of the Invention

The resource allocation method according to the present invention is a communication system for transmitting data in a subframe unit including at least one OFDM symbol, the at least one zone including a plurality of subcarriers adjacent to each other in a frequency domain Constructing a chunk; Assigning the zone chunk to a particular frequency domain according to a distributed allocation method; And allocating the zone chunks to the remaining areas other than the allocated frequency domains according to a distributed allocation method.

In addition, the present invention is a communication system for transmitting data in a unit of a subframe including at least one OFDM symbol, at least one distributed chunk including a plurality of subcarriers that are not adjacent to each other in the frequency domain ( Configuring Chunk); Constituting a plurality of zone chunks including a plurality of subcarriers transmitted through a plurality of consecutive frequency domains, wherein the zone chunks include remaining subcarriers other than the subcarriers included in the distributed chunks; And assigning the distributed chunk and the zone chunk to a particular user.

Work of invention Example

The present invention uses a communication method using a subcarrier which transmits data using a plurality of subcarriers but maintains orthogonality among the plurality of subcarriers. Therefore, the present invention can be performed by a communication method such as OFDM, OFDMA, SC-FDMA.

In the present invention, resources are allocated in units of chunks. The chunk comprises at least one subcarrier. However, chunks according to the present invention are preferably used in two types. The first kind is a chunk of subcarriers adjacent to each other. The chunk described in FIG. 2 is the first kind of chunk. Hereinafter, for convenience of description, the first kind of chunk is referred to as 'localized chunk' or 'Chunk_L'. The second kind of chunk is a chunk that is not adjacent to each other, i.e., consisting of distributed subcarriers. Hereinafter, for convenience of description, the second type of chunk is referred to as 'distributed chunk' or 'Chunk_D'. Additional details on the second chunk will be described in more detail through the embodiments of the present invention.

The zone chunk may be allocated to a user UE according to the distributed allocation method described with reference to FIG. 2 (a) and allocated to the user according to the localized allocation method described with reference to FIG. 2 (b). May be In addition, the distributed chunk may also be allocated to a user UE according to the distributed allocation method described with reference to FIG. 2 (a), and the user according to the localized allocation method described with reference to FIG. 2 (b). Can be assigned to.

That is, the above-described division of the zone chunk and the distributed chunk is a division regarding a method of generating the chunk itself, and the above-mentioned distribution allocation method and the zone allocation method are divisions regarding a method of allocating the generated chunk to the user.

The present invention is characterized by the combination of the two types of chunks and the two types of allocation methods. Specific operations, features, and effects of the present invention will be further embodied by one embodiment of the present invention described below.

First Example

The first embodiment describes a method of performing resource allocation using the zone chunk. More specifically, a method of performing a distributed allocation method for the zone chunk and additionally performing a zone allocation method will be described.

4A is a diagram illustrating an example in which a distributed allocation method and a zone allocation method are applied to a zone chunk according to the first embodiment.

A transmitting side (for example, a base station) having a scheduler determines an index (D Index) for applying the distributed allocation method and an index (L Index) for applying the zone allocation method. The information about the D Index and the L Index is defined in advance and shared to the transmitting / receiving side, or transmitted from the transmitting side to the receiving side (eg, a user UE). When transmitted from the transmitting side to the receiving side may be informed through the layer signaling.

Each index (D Index and L Index) represents a specific chunk. Hereinafter, assigning a specific index to a specific user means assigning a specific chunk to a specific user. The specific user communicates using subcarriers of the allocated chunk.

In the example of FIG. 4A, a specific chunk is assigned to each user by using the above-mentioned two indexes (D Index and L Index). Further, the L Index is sequentially indexed for a specific frequency resource, and the D Index is randomly indexed. That is, the L Index is assigned to the specific frequency resource sequentially, and the D Index is assigned to the particular frequency resource non-sequentially. Another way of configuring D Index is to distribute the frequency resources between adjacent indexes.

As described above, when two kinds of indices having different characteristics are used, there is an advantage in that signaling transmission between the transmitting and receiving sides can be simplified.

In the example of FIG. 4A, the total chunk number N _T is 32, and UE1 and UE3 are allocated Chunk_L by the distributed allocation method. In addition, UE2 and UE4 are allocated Chunk_L by the zone allocation method. In addition, UE1 is allocated six Chunk_Ls according to the distributed allocation method, and UE3 is assigned four Chunk_Ls according to the distributed allocation method. In addition, UE2 is allocated 8 Chunk_Ls according to the zone allocation method, and UE4 is allocated 14 Chunk_Ls according to the zone allocation method.

The transmitting side according to the present embodiment allocates D Index Nos. 0 to 5 Chunk_L to UE1 and allocates D Index Nos. 6 to 9 Chunk_L for UE3. Even if Chunk_L is allocated to successive index numbers for the UE1 and the UE3, it is applied to the distributed allocation method according to the characteristics of the D Index.

As described above, when the step of giving the D Index is performed, the step of giving the L Index is performed. According to the allocation method according to the present embodiment, the UE2 is assigned L Chunks 0 to 10 Chunk_L and the UE4 is allocated L Chunks 11 to 30 Chunk_L. In order to allocate 8 chunks to the UE2, an L Index of 0 to 7 may be assigned, but since the chunks already allocated by the distributed allocation method should not be duplicated, Chunk_L except for the chunks already allocated. L indexes 0 to 10 are allocated to allocate to the UE2. For the same reason for the UE4, Chunk_L of L Index 11 to 31 is allocated.

The allocation method according to the first embodiment has an advantage of using a distributed allocation method and a zone allocation method for Chunk_L. In addition, each allocation is performed and displayed using two indexes having different characteristics, so that the receiving side, which has received the index information, can accurately grasp the chunk assigned thereto.

In the example of FIG. 4A, although two indexes having different characteristics are used, it is also possible to use one index having the same characteristic. That is, the distributed allocation method and the zone allocation method may be performed using only one L Index without distinguishing between the D Index and the L Index. In this case, however, consecutive indexes cannot be allocated to apply the distributed allocation method. That is, the index of 1, 9, 12, 18, 27, and 31 should be assigned to the UE1 of FIG. In general, it is preferable to use two indices having different characteristics as described above, since it is advantageous to reduce the signaling. In the case of using one of the above-mentioned indexes, all of the index numbers by the above distributed allocation method are transmitted to the receiving side.

In addition to the method of notifying the start and end of the index in a manner of notifying the allocation of the chunks used for the UEs from the transmitting side to the receiving side as described above, a method of notifying the starting point and the number of used chunks of the index may be considered. That is, in the case of UE1, the information of the D index starting point 0 and the number of chunks used is signaled, and the UE3 is the starting point of the D index starting point 6 and the information of the number of chunks used four times. Is signaled, and UE4 is signaled with information of the starting point 11 and the number of chunks used 14 of the L Index.

In the example of FIG. 4A, frequency hopping may be performed by changing the D Index for Chunk_L for each specific number of OFDM symbols. The frequency hopping technique is described with reference to FIG. 4B.

4B shows an example of performing frequency hopping every symbol.

First, resources are allocated to the first symbol as in FIG. 4A.

In the second symbol, the D Index for the Chunk_L is changed. That is, D Index 0 through 5 were allocated to UE1 in the first symbol, and D Index 6 through 9 were allocated to UE2. In the second symbol, D Index 10 through 15 were allocated to UE1. , D index 16 to 19 may be allocated to UE2. In the second symbol, the L Index for Chunk_L is given so as not to overlap with the D Index. As a result, each UE is allocated a certain number of chunks, but is allocated a different frequency resource than the first symbol.

The third symbol also changes the D Index for Chunk_L. That is, in the second symbol, D index 10 to 15 is allocated to UE1, and D index 16 to 19 is allocated to UE2. In the third symbol, D Index 20 to 25 is allocated to UE1. D index 26 to 29 may be allocated to UE2. In the third symbol, the L Index for Chunk_L is given so as not to overlap with the D Index. As a result, each UE is allocated a certain number of chunks, but is allocated a different frequency resource than the second symbol.

2nd Example

The second embodiment describes a method of performing resource allocation using the zone chunk. More specifically, a method of performing a distributed allocation method for the zone chunk and additionally performing a zone allocation method will be described. In the first embodiment, a specific user UE has been assigned at least one chunk. However, in the first embodiment, one chunk is allocated to one user, but in the second embodiment, it may be allocated to a plurality of users.

5A is a diagram illustrating an example in which a distributed allocation method and a zone allocation method are applied to a zone chunk according to the second embodiment.

A transmitter having a scheduler determines an index for applying the distributed allocation method and an index for applying the zone allocation method. The information about the D Index and the L Index is defined in advance and shared to the transmission / reception side or transmitted from the transmission side to the reception side. When transmitted from the transmitting side to the receiving side may be informed through the layer signaling.

Each index (D Index and L Index) represents a specific chunk. Hereinafter, assigning a specific index to a specific user means assigning a specific chunk to a specific user. The specific user communicates using subcarriers of the allocated chunk.

In the example of FIG. 5A, a specific chunk is assigned to each user by using the above-mentioned two indexes (D Index and L Index). Further, the L Index is sequentially indexed for a specific frequency resource, and the D Index is randomly indexed. That is, the L Index is assigned to the specific frequency resource sequentially, and the D Index is assigned to the particular frequency resource non-sequentially.

As described above, when two kinds of indices having different characteristics are used, there is an advantage in that signaling transmission between the transmitting and receiving sides can be simplified.

In the example of FIG. 5A, the total chunk number N _T is 32, and UE1 and UE3 are assigned Chunk_L. In addition, UE2 and UE4 are assigned Chunk_L. More specifically, the UE1 and the UE3 are allocated 10 Chunk_Ls according to the distributed allocation method. In this case, the UE1 and the UE3 are mutually exclusively allocated radio resources of one specific Chunk_L. That is, when Chunk_L having D Index 1 is allocated, the UE1 may be allocated 6/10 of the subcarriers of the Chunk_L, and the UE3 may be allocated the remaining 4/10 subcarriers. The UE2 is allocated 8 Chunk_Ls according to the zone allocation method, and the UE4 is allocated 14 Chunk_Ls according to the zone allocation method.

The transmitting side according to the present embodiment allocates Chunk_L of D Index 0 to No. 9 to UE1 and UE3. Even if Chunk_L is allocated to successive index numbers for the UE1 and the UE3, it is applied to the distributed allocation method according to the characteristics of the D Index.

As described above, when the step of giving the D Index is performed, the step of giving the L Index is performed. According to the allocation method according to the present embodiment, the UE2 is assigned L Chunks 0 to 10 Chunk_L and the UE4 is allocated L Chunks 11 to 30 Chunk_L. In order to allocate 8 chunks to the UE2, an L Index of 0 to 7 may be assigned, but since the chunks already allocated by the distributed allocation method should not be duplicated, Chunk_L except for the chunks already allocated. L indexes 0 to 10 are allocated to allocate to the UE2. For the same reason for the UE4, Chunk_L of 11 to 30 L Index is allocated.

The allocation method according to the second embodiment has an advantage of using a distributed allocation method and a zone allocation method for Chunk_L. In addition, each allocation is performed and displayed using two indexes having different characteristics, so that the receiving side, which has received the index information, can accurately grasp the chunk assigned thereto.

In the example of FIG. 5A, two indexes having different characteristics are used, but one index having the same characteristic may be used. That is, the distributed allocation method and the zone allocation method may be performed using only the L index without distinguishing between the D Index and the L Index. In this case, however, consecutive indexes cannot be allocated to apply the distributed allocation method. In general, it is more preferable to use two indices having different characteristics as described above, since it is advantageous to reduce the signaling. In the case of using one of the above-mentioned indexes, all of the index numbers by the above distributed allocation method are transmitted to the receiving side.

In the example of FIG. 5A, frequency hopping may be performed by changing the D Index for Chunk_L for each specific number of OFDM symbols. The frequency hopping technique is described with reference to FIG. 5B.

5B shows an example of performing frequency hopping every symbol.

First, resources are allocated to the first symbol as in FIG. 5A.

In the second symbol, the D Index for the Chunk_L is changed. That is, D Index 0 to 10 times are allocated to UE1 and UE3 in the first symbol, and D Index 10 to 15 times may be allocated to UE1 and UE3 in the second symbol. In the second symbol, the L Index for Chunk_L is given so as not to overlap with the D Index. As a result, each UE is allocated a certain number of chunks, but is allocated a different frequency resource than the first symbol.

The third symbol also changes the D Index for Chunk_L. That is, D Index 10 through 19 are allocated to UE1 and UE3 in the second symbol, and D Index 20 through 29 may be allocated to UE1 and UE3 in the third symbol. In the third symbol, the L Index for Chunk_L is given so as not to overlap with the D Index. As a result, each UE is allocated a certain number of chunks, but is allocated a different frequency resource than the second symbol.

The third Example

In the third and fourth embodiments according to the present invention, resource allocation is performed using the zone chunk and the distributed chunk according to the present invention. More specifically, the area chunk and the distributed chunk are used together for a specific OFDM symbol to perform communication. That is, communication is performed by multiplexing the zone chunks and the distributed chunks.

Hereinafter, the dispersion chunk used in this embodiment is described.

As described above, the distributed chunk and the zone chunk represent a plurality of subcarriers. There is no limit to the number of subcarriers included in the chunk. In addition, the subcarriers included in the distributed chunk and the zone chunk may be configured in various patterns. For example, the subcarriers included in the zone chunks are concatenated. That is, when the subcarrier is indexed by an integer such as 0, 1, 2, 3, etc., if the first zone chunk_L1 includes the 0, 1, 2, 3 subcarriers, the second zone chunk_L2 May include fourth, fifth, sixth, seventh subcarriers. On the other hand, subcarriers included in the distributed chunk are dispersed without being connected. For example, the first distributed chunk Chunk_D1 may include 0, 4, 9, and 14 subcarriers, and the second distributed chunk Chunk_D2 may include second, 6, 11, and 17 subcarriers.

In this embodiment, the distributed chunk and zone chunk are assigned to a particular user, and at least one chunk is assigned to one user. For example, chunks 1, 2, and 3 may be assigned to user 1, and chunks 4 and 5 may be assigned to user 2. One chunk may also be assigned to multiple users. In other words, when data is transmitted in a broadcast form, a specific chunk is allocated to a plurality of users. For example, chunks 1,2 may be assigned to users 1 and 2, and chunk 3 may be assigned to user 3.

When the transmitting side and the receiving side know the information about the subcarriers included in the chunk together, the transmitting side transmits an index indicating a specific chunk to the receiving side, and the receiving side receives the index information so that the specific chunk can identify which subcarrier. You can see if it does. That is, when the index information indicating the chunk allocated to a specific receiver is transmitted, the receiver may know the subcarrier allocated to itself through the index information. Through the above-described operation, the transmitting side can efficiently transmit allocation information for a plurality of subcarriers through small size signaling.

FIG. 6 is a diagram illustrating distributed chunks (Chunk_D) and zone chunks (Chunk_L) used in an embodiment of the present invention. The pattern of subcarriers included in the distributed chunk and the zone chunk used in the present embodiment is more preferably determined by a method of allocating the chunk to the user. For example, when allocating the chunk to a user according to the distributed allocation method, it is preferable to use the distributed chunk Chunk_D. This is because the distributed allocation method has an advantage of allocating chunks over the entire frequency domain to a specific user, thereby obtaining a gain in frequency diversity. In addition, when the chunk is allocated to the user according to the zone allocation method, it is preferable to use the zone chunk Chunk_L. This is because the zone allocation method is a method of allocating chunks of bands adjacent to each other to a specific user in all frequency bands applied to a communication system. The zone allocation method may obtain a user diversity effect by improving the SINR characteristic of each user by allocating a frequency region having a good channel state to the user. That is, since the channels for a particular first user and a second user are different, the quality of data transmitted by a particular frequency domain will be different for the first and second users. In this case, the chunk corresponding to the continuous frequency domain showing the good quality for the first user is allocated to the first user, and the chunk corresponding to the continuous frequency domain showing the good quality for the second user. By assigning to the second user, a user diversity effect can be obtained.

An example of the zone chunks and the distributed chunks shown in FIG. 6 is as follows. In the case of the first zone chunk (Chunk_L1), subcarriers of 201 to 208 are included. That is, it is preferable that Chunk_L1 includes the subcarriers 201 to 208 to be concatenated. The first distributed chunk Chunk_D1 may include subcarriers 301 to 308. In addition, the second distributed chunk Chunk_D2 may include 311 to 318 subcarriers. As described above, the Chunk_D1 includes 301 to 308 subcarriers distributed to each other, and the Chunk_D2 includes 311 to 318 subcarriers distributed to each other.

Table 1 summarizes the relationship between the total 80 subcarriers shown in FIG. 6 and the Chunk_L and the Chunk_D.

Hereinafter, a detailed method of performing resource allocation through the zone chunk and the distributed chunk according to the third embodiment will be described.

FIG. 7 is a diagram showing an example in the case of using a combination of zone chunks and distributed chunks in the FDM scheme according to the third embodiment. As shown, the OFDM sub frame includes seven OFDM symbols. In the example of FIG. 7, OFDM symbols included in the OFDM subframe are transmitted through 80 subcarriers of Table 1.

In the example of FIG. 7, the first OFDM symbol includes a pilot signal, and the pilot signal may be used for channel estimation and equalization with signal values already known to the transmitting and receiving side. The location of the OFDM symbol is not limited, and may be included in the entire second OFDM symbol, part of a subcarrier for the second OFDM symbol, or may be included in a plurality of OFDM symbols. In the example of FIG. 7, the first OFDM symbol may include control information for the chunk or subcarrier arranged in the OFDM subframe in addition to the pilot signal.

In the example of FIG. 7, the zone chunk and the distributed chunk are multiplexed in one OFDM subframe, and the distributed chunk is allocated to a specific frequency domain (subcarrier), and the zone chunk is allocated to the remaining frequency domain (subcarrier). Was assigned. Therefore, the example of FIG. 7 multiplexes the said distributed chunk and the zone chunk by the frequency division multiplexing (FDM) method.

The embodiment of FIG. 7 allocates the distributed chunk first and then allocates the zone chunk in order to further distribute the subcarriers included in the distributed chunk. That is, when three distributed chunks (Chunk_D1, Chunk_D2, Chunk_D3) are allocated and ten zone chunks (Chunk_L1, Chunk_L2, Chunk_L3, ..., Chunk_L10) are allocated to the OFDM subframe of FIG. The Chunk_D1, Chunk_D2, and Chunk_D3 are allocated.

As described above, the third embodiment first allocates the distributed chunk, and then allocates the zone chunk. As shown, Chunk_D1 and Chunk_D2 are allocated to UE1, and Chunk_D3 is preferentially allocated to UE2. After the allocation to Chunk_D, Chunk_L1 to Chunk_L4 is allocated to UE3, and Chunk_L5 to Chunk_L10 are allocated to UE4.

That is, since the UE1 and the UE2 are allocated Chunk_D, since the allocation to the Chunk_D is performed first, the Chunk_D1 to Chunk_D3 allocated to the UE1 and the UE2 include all eight subcarriers shown in Table 1 above. On the other hand, since UE3 and UE4 are allocated Chunk_L, the allocation to the Chunk_D is performed preferentially, so that Chunk_L1 to Chunk_D10 allocated to the UE3 and UE4 do not overlap the Chunk_L among the eight subcarriers shown in Table 1 above. It includes a subcarrier.

That is, the relationship between the chunk and the subcarrier for the example of FIG. 7 is as follows.

In the example of FIG. 7, allocation of chunks is performed in units of one subframe. However, the example of FIG. 7 is only an example for describing the present invention. Resource allocation may be performed in units of frames including at least one OFDM symbol.

In the example of FIG. 7, for convenience of description, subcarriers in which each distributed chunk is uniformly distributed at equal intervals are included, but are not limited thereto. For example, in FIG. 7, the Chunk_D1 includes subcarriers of 1, 11, 21, 31, 41, 51, 61, and 71, but the ratio is 1, 5, 7, 31, 41, 51, 61, and 65. It may also include a uniform subcarrier.

Hereinafter, an example in which a frequency hopping technique is applied to the third embodiment will be described.

When using distributed chunks as in the third embodiment, a frequency hopping technique may be additionally used to increase interference and frequency diversity effects between adjacent cells. The frequency hopping technique is to replace subcarriers included in the distributed chunk for a specific number of OFDM symbols according to a specific hopping pattern. More preferably, the combination of subcarriers included in the distributed chunk can be changed for every OFDM symbol. An example of the frequency hopping technique described below includes assigning a specific logical chunk to a user, setting a physical chunk corresponding to the logical chunk, and maintaining the logical chunk with the logical chunk. A method of exchanging physical chunks corresponding to the following will be described. Hereinafter, the logical chunk is represented by 'Chunk_DL' and the physical chunk is represented by 'Chunk_DP'.

For example, in FIG. 7, UE2 is allocated Chunk_D3, and UE2 is allocated logical chunk Chunk_DL3, and the logical chunk corresponds to the physical chunk Chunk_DP3.

Table 3 below shows an example of a change in correspondence between the logical chunk and the physical chunk according to the change of the OFDM symbol.

For example, a user who is assigned Chunk_DL1 is assigned a subcarrier of Chunk_DP1 during the first OFDM symbol (symbol 1), is assigned a subcarrier of Chunk_DP2 during the second OFDM symbol (symbol 2), and receives a third OFDM symbol (symbol). 3) Subcarriers of Chunk_DP3 are allocated. That is, a particular logical chunk is fixed, but because the mapping relationship between the logical chunk and the physical chunk changes, the frequency for a particular user will continue to change.

Table 4 below is an example showing subcarriers included in a specific physical chunk.

For the result of performing resource allocation in the example of FIG. 7, performing frequency hopping using Tables 3 and 4 is shown in Table 5 below. In the third embodiment, distributed chunks are preferentially allocated, and then zone chunks are allocated, so that the remaining subcarriers other than the subcarriers changed by frequency hopping are included in the zone chunks.

The features of Chunk_D used in the third embodiment will be described below. It is preferable that subcarriers included in Chunk_D of FIG. 7 are distributed among chunks having consecutive indices. First, Chunk_D1 includes subcarriers # 1, # 11, # 21, # 31, # 41, # 51, # 61, and # 71. In addition, Chunk_D2 also includes eight subcarriers, and the eight subcarriers are # 7, # 17, # 27, # 37, # 47, # 57, # 67, and # 77 subcarriers, respectively. The indices of Chunk_D1 and Chunk_D2 are continuous with each other by 1 and 2, respectively. Subcarriers included in Chunk_D given with consecutive indices are not adjacent to each other. In general, in order to reduce control information transmitted to a receiving side, one receiving side is allocated a chunk having indices that are continuous to each other. For example, it is common to assign the chunks with indexes 1, 2, 3, 4, 5, 6 to the first receiving side rather than the chunks with indexes 1, 6, 7, 10, 13, 14. This is because when the chunks having consecutive indexes are allocated to each other, information on the indexes can be reduced. In this case, since the subcarriers included in the Chunk_D received with the continuous indexes are not adjacent to each other, the chunk may include more distributed subcarriers.

As another example, the index may not be allocated continuously so that the Chunk_D includes the distributed subcarriers. For example, by changing the configuration of FIG. 7, Chunk_D1 having index 1 includes # 1, # 5, # 9, # 13, # 17, and # 21 subcarriers, and Chunk_D2 having index 2 has # 2, # The chunk Chunk_D6 having 6, # 10, # 14, # 18, and # 22 subcarriers, and having the index 6 may include # 27, # 31, # 35, # 39, # 43, and # 47 subcarriers. . In this case, when two chunks are allocated to the first receiving side, an index may be allocated in consideration of subcarriers included in each chunk without allocating the Chunk_D1 and Chunk_D2. That is, Chunk_D1 and Chunk_D6 may be allocated or Chunk_D2 and Chunk_D6 may be allocated. In this case, the size of the information for each index is increased, there is an advantage that the assignment of sub-carriers arranged in each chunk is easily performed.

4th Example

In a fourth embodiment of the present invention, resource allocation is performed using the distributed chunk and the zone chunk together. That is, the fourth embodiment provides a method of performing communication by multiplexing the distributed chunks and the zone chunks. The zone chunks according to the fourth embodiment include the same number of subcarriers. Hereinafter, a fourth embodiment will be described with reference to FIG. 8.

8 is a diagram illustrating an example of a method of multiplexing the above distributed chunks and zone chunks according to the fourth embodiment. The example of FIG. 8 has different features from the example of FIG. 7. Since the embodiment of FIG. 7 preferentially allocates the distributed chunks, the distributed chunk includes a certain number of subcarriers. However, since the zone chunk includes the remaining subcarriers that do not overlap the distributed chunk, the number of subcarriers included in the zone chunk may not be constant. For example, in FIG. 7, Chunk_L1 is five, Chunk_L2 is six, Chunk_L3 is five, Chunk_L4 is six, Chunk_L5 is six, Chunk_L6 is five, Chunk_L7 is six, Chunk_L8 is five, Chunk_L9 Is 6 and Chunk_L10 includes 6 subcarriers. As a result, in the case of FIG. 7, since each chunk includes a different number of subcarriers, the number of data symbols that each chunk can transmit is also different. In contrast, the example of FIG. 8 includes the same number of subcarriers in the zone chunk. In FIG. 8, Legacy Chunk_L represents Chunk_L according to FIG. 7. The characteristics of FIG. 8 may be understood by comparing Legacy Chunk_L and Chunk_L according to FIG. 8.

Hereinafter, an example in which the region chunks include the same number of subcarriers will be described with reference to FIG. 8. In the example of FIG. 8, the number of subcarriers of Chunk_L and Chunk_D is the same, but the number of subcarriers of Chunk_L and Chunk_D may be different.

The transmitter according to the example of FIG. 8 may determine the number of Chunk_D and Chunk_L based on information such as the quality of the channel, the degree of change of the channel, and the state of the terminal. 8 allocates three Chunk_D, and the Chunk_D includes eight subcarriers. This embodiment assigns Chunk_D1 and Chunk_D2 to UE1, and preferentially assigns Chunk_D3 to UE2. After the allocation to Chunk_D, Chunk_L1 to Chunk_L4 are allocated to UE3, and Chunk_L5 to Chunk_L7 are allocated to UE4. In the present embodiment, the three distributed chunks Chunk_D1, Chunk_D2, and Chunk_D3 are preferentially allocated. The Chunk_D1 is assigned a # 1 subcarrier, a # 11 subcarrier, a # 21 subcarrier, a # 31 subcarrier, a # 41 subcarrier, a # 51 subcarrier, a # 61 subcarrier, and a # 71 subcarrier. In addition, the Chunk_D2 is allocated # 7 subcarrier, # 17 subcarrier, # 27 subcarrier, # 37 subcarrier, # 47 subcarrier, # 57 subcarrier, # 67 subcarrier, and # 77 subcarrier. In addition, Chunk_D3 is assigned # 3 subcarrier, # 13 subcarrier, # 23 subcarrier, # 33 subcarrier, # 43 subcarrier, # 53 subcarrier, # 63 subcarrier, and # 73 subcarrier. Since the transmitting side allocates the distributed chunk, the transmitting side performs the allocation to the area chunk. Twenty four subcarriers have already been allocated and 56 subcarriers are available. Next, when allocating subcarriers to the zone chunk, a preferred number of subcarriers included in one zone chunk is determined first, and 56 subcarriers other than the 24 subcarriers already allocated to the distributed chunk are allocated according to the number of subcarriers. Therefore, when the chunks by the zone allocation method are determined to include eight subcarriers, the chunks by the zone allocation method are determined to be seven (Chunk_L1, Chunk_L2, Chunk_L3, ..., Chunk_L7). As described above, since the subcarriers included in the zone chunk are concatenated, the Chunk_L1 is subcarriers # 1 to # 13 except for subcarriers # 1, # 3, # 7, # 11, and # 13 (that is, # 2, # 4, # 5, # 6, # 8, # 9, # 10, and # 12 subcarriers). As a result, since the # 1 to # 13 subcarriers are concatenated subcarriers, the Chunk_L1 is a subcarrier according to the Chunk_D (# 1, # 3, # 7, # 11) in the range of the # 1 to # 13 subcarriers. Subcarriers except # 13 subcarriers are allocated. In addition, the Chunk_L2 is subcarriers # 14 to # 24 except for # 17, # 21 and # 23 subcarriers (that is, # 14, # 15, # 16, # 18, # 19, # 20, # 22, and # 24). Subcarriers) are allocated. In this way, seven Chunk_Ls can be configured.

As described above, the seven chunks (Chunk_L1, Chunk_L2, Chunk_L3, ..., Chunk_L7) are allocated subcarriers to which Chunk_D is not assigned, but are allocated subcarriers that are concatenated. The fourth embodiment has the following advantages. First, there is an advantage in that subcarriers included in each distributed chunk are sufficiently distributed by allocating the distributed chunks first. Secondly, the zone chunk can transmit a certain number of data symbols, which makes scheduling more efficient at the transmitting side. In the above example, each of Chunk_D and Chunk_L includes eight subcarriers. However, in this embodiment, the number of subcarriers included in the Chunk_D and Chunk_L may be the same or different. For example, eight subcarriers may be included in Chunk_D and seven subcarriers may be included in Chunk_L.

Hereinafter, an example in which a frequency hopping technique is applied to the fourth embodiment will be described.

When distributed chunks are used as in the fourth embodiment, a frequency hopping technique may be additionally used to increase interference and frequency diversity effects between adjacent cells. The frequency hopping technique is to replace subcarriers included in the distributed chunk for a specific number of OFDM symbols according to a specific hopping pattern. More preferably, the combination of subcarriers included in the distributed chunk can be changed for every OFDM symbol. An example of the frequency hopping technique described below is to assign a specific logical chunk (Chunk_DL) to a user, set a physical chunk (Chunk_DP) corresponding to the logical chunk, and maintain the logical chunk to the physical logical chunk. A method of exchanging corresponding physical chunks is described. For example, in FIG. 8, UE2 is allocated Chunk_D3, and UE2 is allocated logical chunk Chunk_DL3, and the logical chunk corresponds to the physical chunk Chunk_DP3.

Table 6 below shows an example of a change in correspondence between the logical chunk and the physical chunk according to the change of the OFDM symbol.

For example, a user who is assigned Chunk_DL1 is assigned a subcarrier of Chunk_DP1 for the first OFDM symbol (symbol 1), a subcarrier of Chunk_DP2 is assigned to the second OFDM symbol (symbol 2), and a third OFDM symbol. A subcarrier of Chunk_DP3 is assigned to (symbol 3). That is, a particular logical chunk is fixed, but because the mapping relationship between the logical chunk and the physical chunk changes, the frequency for a particular user keeps changing.

Table 7 below shows an example of a subcarrier included in a specific physical chunk.

For the result of performing resource allocation in the example of FIG. 8, frequency hopping is performed using Tables 6 and 7 as shown in Table 8 below. In the case of the fourth embodiment, distributed chunks are preferentially allocated and then zone chunks are allocated, so that the remaining subcarriers are included in the zone chunks except the subcarriers changed by frequency hopping.

Hereinafter, the features of Chunk_D according to the example of FIG. 8 will be described. The subcarriers included in Chunk_D are preferably distributed among the chunks having indices that are continuous to each other. First, Chunk_D1 of FIG. 8 includes subcarriers # 1, # 11, # 21, # 31, # 41, # 51, # 61, and # 71. In addition, Chunk_D2 also includes eight subcarriers, and the eight subcarriers are # 7, # 17, # 27, # 37, # 47, # 57, # 67, and # 77 subcarriers, respectively. The indices of Chunk_D1 and Chunk_D2 are continuous with each other by 1 and 2, respectively. Subcarriers included in Chunk_D given with consecutive indices are not adjacent to each other. In general, in order to reduce control information transmitted to a receiving side, one receiving side is allocated a chunk having indices that are continuous to each other. For example, it is common to assign the chunks with indexes 1, 2, 3, 4, 5, 6 to the first receiving side rather than the chunks with indexes 1, 6, 7, 10, 13, 14. This is because when the chunks having consecutive indexes are allocated to each other, information on the indexes can be reduced. In this case, since the subcarriers included in the Chunk_D received with the continuous indexes are not adjacent to each other, the chunk may include more distributed subcarriers.

As another example, the index may not be allocated continuously so that the Chunk_D includes the distributed subcarriers. For example, Chunk_D1 with index 1 includes # 1, # 5, # 9, # 13, # 17, # 21 subcarriers, and Chunk_D2 with index 2 has # 2, # 6, # 10, # 14. , # 18, # 22 subcarriers, and Chunk_D6 having an index 6 may include # 27, # 31, # 35, # 39, # 43, and # 47 subcarriers. In this case, when two chunks are allocated to the first receiving side, an index may be allocated in consideration of subcarriers included in each chunk without allocating the Chunk_D1 and Chunk_D2. That is, Chunk_D1 and Chunk_D6 may be allocated or Chunk_D2 and Chunk_D6 may be allocated. In this case, the size of the information for each index is increased, there is an advantage that the assignment of sub-carriers arranged in each chunk is easily performed.

The transmitting side according to the present invention may determine the receiving side assigned to Chunk_L by using channel quality information (CQI) fed back from the receiving side. For example, in the case of Figure 8, five CQI information is received. The five CQI information may be transmitted separately from each receiving side, and the transmitting side may use the plurality of CQI information to know what band quality is excellent for a particular receiving side. The transmitting side may allocate Chunk_L through the channel having the highest quality to each receiving side by using the CQI, thereby obtaining a user diversity effect.

If the frequency band indicated by the CQI information is fixed as in the case of FIG. 8, different CQI regions may overlap one Chunk_L. That is, CQI 1 of FIG. 8 represents channel quality for frequency bands of # 1 to # 16 subcarriers, and CQI 2 represents channel quality for frequency bands of # 17 to # 32 subcarriers. In case of feeding back information indicating that the channel quality is good and feeding back information indicating that the channel quality is bad, it may be a question whether or not the frequency band in which the Chunk_L2 is transmitted is determined to be a good quality band. In this case, since Chunk_L2 includes more frequency bands of CQI 2, the transmitting side may allocate Chunk_L2 to a specific receiving side entirely based on CQI 2 information. In addition, the transmitting side may assign weights by the ratio of the number of subcarriers included in the corresponding CQI region and allocate Chunk_L2 to a specific receiving side according to the averaged value.

Fifth Embodiment

The fifth embodiment describes a resource allocation method combining the first to fourth embodiments. The first to fourth embodiments may be freely combined with each other according to a change in a communication environment or whether a specific condition is satisfied. That is, the radio resources are allocated through the first embodiment. If a specific condition is satisfied, the radio resources may be allocated through the third embodiment or the fourth embodiment. In addition, the radio resources are allocated through the second embodiment. If a specific condition is satisfied, the radio resources may be allocated through the third embodiment or the fourth embodiment. It is more preferable that the switching between the above embodiments be switched in a specific sub frame unit or in a specific time unit.

The reason for combining the respective embodiments according to the fifth embodiment is that the characteristics of the first to fourth embodiments are different.

The first and second embodiments have an advantage that the configuration of the chunk is simple because resource allocation is performed using only Chunk_L. However, when the number of chunk_Ls allocated by the distributed allocation method is small, it is difficult to sufficiently obtain the frequency diversity gain.

In the third and fourth embodiments, the configuration of the chunk is complicated because resource allocation is performed using Chunk_L and Chunk_D. However, since Chunk_D generates a frequency diversity gain by itself, sufficient frequency diversity gain can be obtained through a small number of Chunk_D.

Switching between each of the above embodiments is preferably performed according to specific conditions. More specifically, the first or second embodiment may be performed, and the third or fourth embodiment may be performed when a favorable condition of performing the third or fourth embodiment is completed. A more specific example is as follows.

When performing the first embodiment, it is preferable to determine switching between the embodiments based on UEs assigned Chunk_L by the distributed allocation method. More specifically, it is preferable to switch to the third or fourth embodiment when the number of Chunk_L allocated to UEs allocated to Chunk_L by the distributed allocation method falls below a specific threshold. For example, according to the first exemplary embodiment, Chunk_L1 and L2 may be allocated to UE1, Chunk_L3, L4, and L5 may be allocated to UE2, and Chunk_L6, L7, L8, and L9 may be allocated to UE3. In this case, by observing the number of Chunk_L allocated to the UE1 to which the least chunk has been allocated, if the threshold value is less than the threshold value, it may be switched to the third or fourth embodiment. Alternatively, by observing the number of Chunk_Ls allocated to the UE3 to which the most chunks are allocated, if it is less than or equal to the threshold value, it may be switched to the third or fourth embodiment. As another method, the sum or average value of the number of chunks allocated to the UE1, the UE2, and the UE3 can be obtained and compared with the threshold value to switch to the third or fourth embodiment.

When the second embodiment is performed, it may be implemented as follows. In the second embodiment, several users share Chunk_L allocated by a distributed allocation method. Therefore, the number of Chunk_Ls assigned to each user by the distributed allocation method is the same as the number of Chunk_L used in the entire distributed allocation method. Therefore, when the number of Chunk_L used in the entire distributed allocation method is observed and falls below a specific threshold, it is preferable to switch to the third or fourth embodiment.

6th Example

The sixth embodiment relates to a method for transmitting resource allocation information to a receiving side (eg, a user UE). That is, when resource allocation according to the present invention is performed, a method of transmitting control information about the performed resource allocation is different. The sixth embodiment proposes a method for efficiently transmitting control information about resource allocation.

A transmitting side (for example, a base station) having a scheduler must inform the receiving side of resource allocation information. In the method for transmitting resource allocation information according to the sixth embodiment, the type of chunk (whether Chunk_L or Chunk_D) assigned to the receiving side or the method in which chunks are allocated (Chunk_L is allocated according to a distributed allocation method or Chunk_L is allocated to a zone). Control information may be transmitted in consideration of whether or not to allocate according to the method).

Hereinafter, when the transmitter allocates resources using only Chunk_L, the control information transmission method according to the sixth embodiment will be described.

The transmitting side according to the sixth embodiment, to a first user assigned Chunk_L by the distributed allocation method, an identifier indicating that the first user has been assigned Chunk_L by the distributed allocation method (hereinafter referred to as 'indicator D'). And only information about Chunk_L allocated to the first user. In addition, the transmitting side, to the second user assigned Chunk_L by the zone allocation method, an identifier indicating that the second user has been assigned Chunk_L by the zone allocation method (hereinafter referred to as 'indicator L'), the entire user It is preferable to transmit all information about Chunk_L allocated by the distributed allocation method and information about Chunk_L allocated to the second user.

Chunk_L allocated by the distributed allocation method is preferentially assigned to Chunk_L allocated by the zone allocation method. Therefore, if the first user only has information about Chunk_L for the first user to which resources are allocated, information on resource allocation can be accurately known. The first user receives the indicator D, and can know that he or she is assigned Chunk_L assigned by a distributed allocation method. Although the second user is not assigned Chunk_L allocated by the distributed allocation method, the second user must know information about Chunk_L allocated by the distributed allocation method. If only the information about the Chunk_L for the second user is known, a problem may arise in which the radio resource of the Chunk_L already allocated by the distributed allocation method and the Chunk_L for the second user collide. Therefore, the second user receives both information about Chunk_L for the second user and information about Chunk_L allocated by the distributed allocation method to all users. The second user receives the indicator L and can see that he or she is assigned Chunk_L assigned by the zone allocation method.

The indicator D and the indicator L may be implemented through one bit. In addition, the information on the specific Chunk_L may be implemented in various ways. For example, when distinguishing the Chunk_L through a specific index, the information about the specific Chunk_L means the specific index. If the index for a specific Chunk_L is transmitted, information about all of the indexes may be transmitted or information about a part of the index may be transmitted. For example, when the index for a specific Chunk_L is a continuous integer, the index information for the specific Chunk_L may be notified by transmitting only the smallest integer value and the largest integer value of the index. Here, the smallest integer value and the largest integer value of the index may be replaced with the smallest integer value and the number of chunks used.

Hereinafter, when a transmitter allocates resources using Chunk_L and Chunk_D together, a control information transmission method according to the sixth embodiment will be described.

The transmitting side according to the sixth embodiment transmits only a first identifier indicating the fact that the first user is assigned Chunk_D and information about the Chunk_D assigned to the first user, to the first user who is assigned Chunk_D. Do. In addition, the transmitting side, to the second user who is assigned Chunk_L, a second identifier indicating that the second user has been assigned Chunk_L, information about Chunk_D assigned to all users, Chunk_L assigned to the second user It is desirable to transmit all the information.

The Chunk_D is preferentially allocated to the Chunk_L. Therefore, if the first user only has information about Chunk_D for the first user to which resources are allocated, information on resource allocation can be accurately known. When the first user receives the first identifier, the first user may know that he or she is assigned Chunk_D. Although the second user is not assigned Chunk_L, the second user must know information about Chunk_D. If only the information about the Chunk_L for the second user is known, a problem may occur in which an already allocated Chunk_D collides with a radio resource of the Chunk_L for the second user. Accordingly, the second user receives both information about Chunk_L for the second user and information about Chunk_D assigned to all users. When the second user receives the second identifier, he / she may know that he or she is assigned Chunk_L.

The first identifier and the second identifier may be implemented through one bit. In addition, one of the first identifier and the second identifier may be omitted, and the receiver may inform the type of the allocated chunk according to whether the remaining identifier is received. In addition, the information about the specific Chunk_L or Chunk_D may be implemented in various ways. For example, when distinguishing the Chunk_L or Chunk_D through a specific index, the information about the specific Chunk_L or Chunk_D means the specific index. If an index for a specific Chunk_L or Chunk_D is transmitted, information about all of the indexes may be transmitted or information about a part of the index may be transmitted. For example, when an index relating to a specific Chunk_L or Chunk_D is a continuous integer, only the smallest and largest integer values of the index may be transmitted to inform the index information of the specific Chunk_L or Chunk_D. Here, the smallest integer value and the largest integer value of the index may be replaced with the smallest integer value and the number of chunks used.

7th Example

The seventh embodiment relates to a method for transmitting resource allocation information to a receiving side (eg, a user UE). That is, when resource allocation according to the present invention is performed, a method of transmitting control information about the performed resource allocation is different. The seventh embodiment improves on the sixth embodiment to transmit more efficient resource allocation information. More specifically, the seventh embodiment transmits resource allocation information using the unified index. The user who receives the unified index generated according to the seventh embodiment may know at one time the type of the allocated chunk and the number of allocated chunks.

Hereinafter, when the transmitter allocates resources using only Chunk_L, the control information transmission method according to the seventh embodiment will be described.

The transmitting side according to the seventh embodiment transmits the unified index indicating the chunks allocated by each user to the first user who is assigned Chunk_L by the distributed allocation method and the second user who is assigned Chunk_L by the zone allocation method. The unified index may be configured in the following manner. The combined index includes information of the D Index and the L Index. For example, assume that the number of chunks by the distributed allocation method is N _i , the number of chunks by the zone allocation method is N _j, and the number of N _j + N _i is fixed. The D Index may be mapped to a 1 to N _i th unified index value, and the L Index value may be mapped to a N _i +1 th to N _j + N _i th unified index values. If the transmitting side informs through the N _i and the integration index, the receiving side can determine the chunk assigned to itself. That is, the receiving side compares the combined index value with the N _i , and if the unified index is small, the unified index indicates D index, and if the unified index is large, the unified index means L Index. The mapping relationship between the D Index, the L Index and the unified index is shared to the transmitting and receiving side.

If the shared N + N _{i j} value in the integration index in the receiving side, the transmission side may notify the N _i N _j by transmitting, instead of the number N _i. That is, the L Index may be mapped to a 1 to N _i th unified index value, and the D Index value may be mapped to a unified index value of 1 + N _i th to N _j + N _i th.

Hereinafter, when the transmitter allocates resources using Chunk_L and Chunk_D, the control information transmission method according to the seventh embodiment will be described.

The transmitting side according to the seventh embodiment transmits the unified index indicating the chunks allocated by each user to the first user who is assigned Chunk_D and the second user who is assigned Chunk_L. It can be configured in the following manner of the unified index. For example, if the index for Chunk_D is 1 to N _i and the index for Chunk_L is 1 to N _j , the unified index is 1 to (N _i + N _j ). In the unified index, indexes of 1 to N _i represent Chunk_L allocated by the distributed allocation method, and indexes of (N _i +1) to (N _i + N _j ) are Chunk_L allocated by the zone allocation method. Can be represented. If the number of (N _i + N _j ) is constant, when the transmitter informs the Chunk_L allocated to the N _i and a specific user through the unified index, the receiver may determine the chunk allocated to the receiver. That is, it is possible to know whether the unified index relates to Chunk_L or Chunk_D by comparing the unified index transmitted to itself with N _i . In other words, the unified index performs not only index information but also identifier function.

The unified index may be configured in a manner different from that described above. For example, an index of 1 to N _j may represent the Chunk_L, and an index of (N _j +1) to (N _i + N _j ) may represent the Chunk_D. If the shared N + N _{i j} value in the reception side, the transmission side may notify the N _i N _j by transmitting, instead of the number N _i.

Using the above-described unified index, it is possible to notify the type of the chunk and the index of the chunk allocated to the receiving side without transmitting a separate indicator to the receiving side.

The resource allocation method according to the first to fifth embodiments described above may be used together with the method for transmitting resource allocation information according to the sixth to seventh embodiments. Since the resource allocation method and the resource allocation information transmission method may be used together, it is obvious to those skilled in the art to which the present invention pertains, and examples of combining the embodiments will be described below. Hereinafter, each example described is only a combination of embodiments according to the present invention, the present invention is not limited to the combination of the embodiments described below.

Hereinafter, an example of using the resource allocation information transmission method according to the first embodiment and the present invention together will be described. 9A is a procedure flowchart illustrating a method of performing resource allocation when using the first embodiment and the sixth embodiment together.

First, the relationship between the two indices and frequency resources shown in FIG. 4A is determined. That is, L Index and D Index are determined, and to which frequency resource (for example, subcarrier) each index is mapped (S901). The information about the index and the frequency resource is shared to the transmitting and receiving side.

The transmitter determines whether to allocate Chunk_L for each user UE by the distributed allocation method or the zone allocation method (S902). First, the case of assigning Chunk_L by the distributed allocation method will be described. The transmitting side equipped with the scheduler sequentially allocates the D Index (S903). When the allocation is completed, control information regarding the resource allocation is generated (S904). According to the sixth embodiment, the transmitting side generates an identifier D for the user UE and generates information about Chunk_L assigned to the user. In the example of FIG. 9A, the information about Chunk_L is the start and end of the D Index assigned to the user. Since the transmitting side sequentially allocates the D Index, the D Index for a specific user is continuous. Therefore, upon receiving the information about the start and end of the D Index, the user can know the radio resource allocated to the user. In this case, the information about the start and the end can be directly informed of the start point and the end point, or the start point and the number of chunks used by the user.

After allocating Chunk_L according to the distributed allocation method, Chunk_L is allocated according to the zone allocation method. When the transmitting side allocates Chunk_L, it is more preferable to assign Chunk_L having a good SINR for a specific user to the specific user. As shown in FIG. 4A, the transmitting side allocates Chunk_L according to the zone allocation method so as not to overlap with Chunk_L according to the distributed allocation method (S905). When the allocation is completed, control information regarding the resource allocation is generated (S906). The transmitting side, according to the sixth embodiment, generates an identifier L for a user UE, generates information about Chunk_L assigned to the user, and relates to Chunk_L allocated to all users by a distributed allocation method. Generate information. In the example of FIG. 9A, the information about the Chunk_L is the beginning and the end of the L Index allocated to the user, and the information about the Chunk_L allocated to the all users by the distributed allocation method means the last value of the entire D Index. Since the D Index is assigned sequentially, the user can know the range of the entire D Index through the last value of the D Index. Through this, it is possible to prevent the collision between the L Index allocated to the D Index. In addition, the user may distinguish resource allocation information regarding D Index and L Index which are exclusively allocated to each other as shown in FIG. 4A. Here, the information of the beginning and the end of the index can be replaced with the information of the start and the number of chunks used, and the last value of the D Index can directly inform the information of the total number of Chunk_L used for the distribution allocation. It is possible.

The resource allocation information is transmitted to the user through a control channel (S907). The resource allocation information may be transmitted through various channels. That is, each identifier, a D index for a specific user, and an L index for a specific user may be transmitted through a dedicated channel for a specific user. However, information common to a plurality of users, such as the last value of the entire D Index, is preferably transmitted through a common channel for a plurality of users.

10A is a diagram illustrating an operation of a user who has received resource allocation information when using the first embodiment and the sixth embodiment together. The user receives a control signal for each user (S1001) and checks whether the chunk allocated to the user is allocated by the distributed allocation method or the zone allocation method through an identifier (S1002). If Chunk_L is allocated by the distributed allocation method, the allocated Chunk_L is checked by looking at the start and end of the D index (S1003). If Chunk_L is allocated by the zone allocation method, all Chunk_L by the distributed allocation method is checked through the last index of the entire D Index (S1004). The user checks Chunk_L assigned to the user by receiving the L Index assigned to the user (S1005). When checking Chunk_L according to the L Index in step S1005, Chunk_L allocated to itself is checked among the remaining radio resources except for all Chunk_L by the distributed allocation method. Here, when the transmitting side informs the start of the index and the number of chunks used instead of the start and end of the index, the start and end can be determined by the start of the index and the number of chunks used.

Application of the above-described sixth embodiment to the example of FIG. 4A is as follows.

First, Chunk_L corresponding to D Index 0 to 5 is allocated to UE1, and Chunk_L is sequentially assigned to D Index 6 to 9 for UE3. The last index of the D index is 9. The transmitting side according to the sixth embodiment transmits the start value 0 and the end value 5 of indicator D and D Index as resource allocation information of UE1. In addition, as resource allocation information of UE3, indicator D and D Index start value 6 and end value 9 are transmitted. For UE2, chunks of L Index 0 to 10 are allocated. In this case, L Index 1, 4, and 9 are already used in D Index and are empty. Therefore, there are eight Chunk_Ls for UE2. As a resource allocation information of UE2, the transmitting side transmits Index 9 which is the last value of the entire D Index, indicator L, 0 which is the start value of the L Index, and 10 which is the end value. Similarly, UE4 allocates IL = 11-30 of the L Index. Resource allocation information of UE4 is the last Index 9, indicator L, L index start 11, end 30 of the entire D Index.

Hereinafter, a specific example of transmitting resource allocation information using the unified index according to the seventh embodiment will be described.

For example, if the combined index is I _M , D Index is I _D , and L Index is I _L , as shown in FIG. 4A, I _D may have an index value of 0 to 31, I _{L may} also have an index value of 0 to 31, but the sum of the chunks by I _D and I _L is fixed at 32. The I _D and I _L may be integrated into I _M having a value of 0 to 31. Can be. One of the various integration methods is described as follows.

First, when constructing an integrated index with respect to D Index, it is maintained as I _M = I _D. The I _D is given sequentially, in the case of Figure 4a has a value of I _D = 0 to 9. When constructing a unified index with respect to L Index, the I _L value is mapped to a value of 0 to 21 in order to prevent overlapping values of I _D and I _L. When the mapped value is called I _L ', the relationship between the I _L and I _L ' and the final I _M is shown in Table 9 below.

The N _DT is the number of Chunk_L allocated by the distributed allocation method. When the transmitting side transmits the N _DT and the unified index, the receiving side knows the resources allocated to itself by using the relation shown in Table 9 in reverse. For instance, _DT is sent to N = 10 to UE2, I _M may be 11, it is transmitted. In this case, UE2 knows that it is assigned Chunk_L by the zone allocation method because the I _M value is larger than the N _DT value, and subtracts N _DT from the I _M value to 1 (I _L '= 1). You know that you are assigned a chunk of I _L = 2. As the UE already knows what frequency range the chunk corresponding to L index 2 represents, the UE receives the resource allocation correctly.

The transmitting end may, instead of transmitting the N _DT may send the number (N _LT) of Chunk_L by the zone allocation. This is because when the N _DT + N _LT value is constant, the point of separation between the L index and the D index can also be identified through the NLT value.

Hereinafter, another configuration method of the integrated index will be described.

According to Table 10, the transmitting side transmits a combined index of 0 to 31. In other words, the transmitting side determines I _M = I _L and transmits an integrated index. That is, the L index is transmitted unchanged. However, since L index does not use some indexes of 0 to 31, an unused I _M occurs among 0 to 31. The D index is mapped to I _M having no value above. The sender sends information about N _DT together.

The UE first uses the I _M value equal to the I _L value. For example, if the I _M received from the UE has 7, it can be seen that the UE has been allocated a chunk of L index 7. However, since the UE also receives information of N _DT = 10, it can be seen that I _L cannot have a value of 1, 4, 9, 12, 15, 18, 19, 26, 27, and 31. If the I _M received by the UE is 4, it can be seen that the UE has been allocated a chunk of D index 7 by the relationship of Table 10 above. Since the relationship between the specific D index and the frequency resource is already known by the transmitting and receiving side, the UE can receive the correct resource allocation.

Hereinafter, an example of using the resource allocation information transmission method according to the second embodiment and the present invention together will be described. A method of performing resource allocation in the case where the second embodiment and the sixth embodiment are used together will be described with reference to FIG. 9B. The second embodiment is a method of sharing a specific chunk to a plurality of users, but similarly to the first embodiment, a resource is allocated using the D Index and the L Index.

First, the relationship between the two indices and frequency resources shown in FIG. 5A is determined. That is, the D Index for the plurality of users and the L Index for each user are determined, and to which frequency resource (eg, subcarrier) each index is mapped is determined (S911). The information about the index and the frequency resource is shared to the transmitting and receiving side.

The transmitting side determines whether Chunk_L is allocated to each user UE by the distributed allocation method or not by the zone allocation method (S912). First, the case of assigning Chunk_L by the distributed allocation method will be described. The transmitting side having the scheduler sequentially allocates the D Index to accumulate the total number of uses (S913). That is, the total number of chunks shared by multiple users is accumulated. When step S913 ends, control information about the resource allocation is generated (S914). According to the sixth embodiment, the transmitting side generates an identifier D for the user UE and generates information about Chunk_L assigned to the user. In the example of FIG. 9B, the information about the Chunk_L is the start index of the D Index assigned to the user and the number of chunks used. In the second embodiment, since multiple users share Chunk_L by the distributed allocation method, several users may eventually be assigned Chunk_L of the same D Index. The sender accumulates the number of Chunk_L used as the distributed allocation of each user to determine the total number of Chunk_L used as the distributed allocation. This value can be recognized as the last index of the D Index. It is possible to find the location of Chunk_L to be shared by all users who are distributed by the last value of the D Index, and to be used by each user in Chunk_L which is shared by the distributed allocation method through the start and end of the assigned D Index. The location of the divided resources and their usage can be identified. Therefore, when the user receives the information about the start and end of the D index, the user can know the Chunk_L assigned to the user.

After allocating Chunk_L for multiple users according to the distributed allocation method, Chunk_L is allocated according to the zone allocation method. When the transmitting side allocates Chunk_L according to the zone allocation method, it is more preferable to assign Chunk_L having a good SINR to the specific user. The transmitting side allocates Chunk_L according to the zone allocation method so as not to overlap with Chunk_L according to the distributed allocation method as shown in FIG. 5A (S915). When the allocation is completed, control information regarding the resource allocation is generated (S916). The transmitting side, according to the sixth embodiment, generates an identifier L for a user UE, generates information about Chunk_L assigned to the user, and relates to Chunk_L allocated to all users by a distributed allocation method. Generate information. In the example of FIG. 9, the information about the Chunk_L is the beginning and the end of the L Index assigned to the user, and the information about the Chunk_L allocated to the all users by the distributed allocation method means the last value of the entire D Index. Since the D Index is assigned sequentially, the user can know the range of the entire D Index through the last value of the D Index. Through this, it is possible to prevent the collision between the L Index allocated to the D Index. In addition, the user may distinguish resource allocation information regarding D Index and L Index, which are exclusively allocated to each other as shown in FIG. 5A. Here, the information of the start and end of the index can be replaced with the number of chunks used and the start of the index. The last value of the D Index can be replaced by the total number of Chunk_Ls that are shared among multiple users and allocated in a distributed allocation method.

The resource allocation information is transmitted to the user through a control channel (S917). The resource allocation information may be transmitted through various channels. That is, each identifier, a D index for a specific user, and an L index for a specific user may be transmitted through a dedicated channel for a specific user. However, information common to a plurality of users, such as the last value of the entire D Index, is preferably transmitted through a common channel for a plurality of users.

10B is a diagram illustrating an operation of a user who has received resource allocation information when using the second embodiment and the sixth embodiment together. ,

The user receives a control signal for each user (S1011) and checks whether the chunk allocated to the user is allocated by the distributed allocation method or the zone allocation method through an identifier (S1012). If Chunk_L is allocated by the distributed allocation method, the final value of D Index is checked to confirm Chunk_L to be shared (S1013). In the second embodiment, multiple users share Chunk_L by the distributed allocation method, and identify the location and amount of resources allocated to them in Chunk_L shared by multiple users through the start and end of the D Index sent to each user. do. If Chunk_L is allocated by the zone allocation method, all Chunk_L by the distributed allocation method is checked through the last index of the entire D Index (S1014). The user checks Chunk_L assigned to the user by receiving the L Index assigned to the user (S1016). When checking Chunk_L according to the L Index in step S1016, it checks the Chunk_L allocated to itself among the remaining radio resources except for all Chunk_L by the distributed allocation method.

Here, when the sender informs the start of the index and the number of chunks used instead of the start and end of the index, the start and end of the index can be determined by the start of the index and the number of chunks used.

The method for transmitting resource allocation information for the second embodiment may be different from the method for transmitting resource allocation information for the first embodiment. This is because chunk_L is divided into L index and D index, and the same method is used in the first and second embodiments. However, the chunk to which the distributed allocation method is applied is shared among multiple users. That is, when a specific UE is allocated Chunk_L, the radio resource is allocated a preset ratio (for example, 6/10 of the entire chunk) instead of all the allocated Chunk_L resources. However, the method of generating the unified index for the second embodiment is the same as the method of generating the unified index for the first embodiment. As shown in FIG. 5A, I _D may have an index value of 0 to 31, and I _{L may} also have an index value of 0 to 31, but the sum of chunks by I _D and I _L is fixed to 32. As such, the I _D and I _L may be integrated into I _M having a value of 0 to 31. First, when constructing an integrated index with respect to D Index, it is maintained as I _M = I _D. The I _D is given sequentially, in the case of Figure 5a has a value of I _D = 0 to 9. When constructing a unified index with respect to L Index, the I _L value is mapped to a value of 0 to 21 in order to prevent overlapping values of I _D and I _L. When the mapped value is called I _L ', the relationship between the I _L and I _L ' and the final I _M is shown in Table 9 above. In addition, the unified index by the relationship of Table 10 can also be applied to the second embodiment.

Hereinafter, an example of using the resource allocation information transmission method according to the third embodiment and the present invention together will be described. 11 is a flowchart illustrating a method of performing resource allocation when using the third embodiment and the sixth embodiment together.

11 is a diagram illustrating a method of transmitting control information on the scheduling task performed by a transmitting side to a receiving side. FIG. 11 relates to a method of transmitting control information when transmitting chunks according to FIG. 7. Hereinafter, a method of transmitting control information about the scheduling task, that is, resource allocation information, to the receiver will be described with reference to FIGS. 7 and 11.

The transmitting side (e.g., any base station) performs a scheduling operation, and designates a receiving side (e.g., user UE) to which the Chunk_D is assigned and allocates as many Chunk_Ds as necessary to the receiving side. (S1101). As an example of multiplexing Chunk_D and Chunk_L as shown in FIG. 7, the transmitting side designates UE1 and UE2 as a receiving side to which Chunk_D is to be allocated. In addition, the transmitter designates the number of Chunk_Ds to be allocated to the UE1 and the UE2. The UE1 assigns Chunk_D1 and Chunk_D2 to the UE1 and assigns Chunk_D3 to the UE2. The index of the chunk allocated to the specific terminal is preferably continuous. That is, it is preferable that Chunk_D1, Chunk_D2 or Chunk_D2, Chunk_D3 be allocated to UE1. This is because when a large number of chunks are allocated to send index information for all the chunks, a problem may arise in that the size of control information transmitted to the receiver increases. The transmitter determines a subcarrier included in the Chunk_D before or after allocating Chunk_D to the UE.

Since the transmitting side allocates a radio resource (eg, a subcarrier) to Chunk_D, Chunk_L may be allocated to the remaining radio resources. In other words, the transmitter configures a map for Chunk_L (S1102). The map for Chunk_L indicates which frequency-time resource a specific chunk is transmitted as shown in FIG. 7. That is, by performing the step of constructing the map, it is possible to determine the subcarriers included in the Chunk_L.

As described above, each chunk is allocated to at least one receiving side, and the transmitting side determines which receiving side to assign the Chunk_L to (S1103). In the example of FIG. 11, Chunk_L1 through Chunk_L4 are allocated to UE3, and Chunk_L5 through Chunk_L10 are allocated to UE4. In spite of the example of FIG. 11, it is also possible for a specific terminal to simultaneously receive Chunk_L and Chunk_D. Therefore, the present invention is not limited to the example of FIG.

Control information according to the scheduling of S1101 to S1103 is transmitted to the terminal. However, the control information is more preferably transmitted through a separate path according to the information. According to the sixth embodiment, the receiving party to which the Chunk_D has been allocated receives a first identifier for notifying whether the Chunk_L or the Chunk_D has been allocated (S1105). One bit is sufficient for the first identifier. In addition, the receiving side further receives an index for distinguishing each chunk (S1106). For example, the receiving side to which Chunk_D is allocated, such as UE1, receives the first identifier that it has been allocated Chunk_D, and further receives the index information that it has been allocated Chunk_D1 and Chunk_D2. When the UE1 receives the information about the first identifier and the index information, the UE1 may know on which subcarrier the chunk allocated for itself is transmitted. If three Chunk_Ds are used, # 1, # 11, # 21, # 31, # 41, # 51, # 61, # 71 subcarriers are assigned to Chunk_D1, and # 7, # 17, # to Chunk_D2. 27, # 37, # 47, # 57, # 67, # 77 subcarriers are assigned, and # 3, # 13, # 23, # 33, # 43, # 53, # 63, # 73 subcarriers are assigned to Chunk_D3. The rule of assignment is because the transmitting and receiving side already knows. That is, the UE1 receives and decodes Chunk_D1 and Chunk_D2 through the first identifier and the index information (S1109).

Receiving side allocated Chunk_L like UE3, 4 is preferably notified of the number of Chunk_D used by the transmitting side through common signaling (S1104, S1110). If the receiving party to which the Chunk_L has been allocated further receives a first identifier (S1107) indicating an allocation scheme and an index (S1108) for distinguishing each Chunk_L, the receiving party may construct a map for the Chunk_L if not informed of the number of Chunk_D. Since there is no number, the number of Chunk_D is notified.

Hereinafter, an example of using the resource allocation information transmission method according to the fourth embodiment and the present invention together will be described. 11 is a flowchart illustrating a method of performing resource allocation when using the fourth and sixth embodiments together.

11 is a diagram illustrating a method of transmitting control information on the scheduling task performed by a transmitting side to a receiving side. FIG. 11 relates to a method of transmitting control information when transmitting chunks according to FIG. 8. Hereinafter, a method of transmitting control information about the scheduling task, that is, resource allocation information, to the receiving side will be described with reference to FIGS. 8 and 11.

The transmitting side (e.g., any base station) performs a scheduling operation, and designates a receiving side (e.g., user UE) to which the Chunk_D is allocated, and allocates as many Chunk_Ds as necessary to the receiving side. (S1101). As an example of multiplexing Chunk_D and Chunk_L as shown in FIG. 8, the transmitting side designates UE1 and UE2 as a receiving side to which Chunk_D is to be allocated. In addition, the transmitter designates the number of Chunk_Ds to be allocated to the UE1 and the UE2. The UE1 assigns Chunk_D1 and Chunk_D2 to the UE1 and assigns Chunk_D3 to the UE2. The index of the chunk allocated to the specific terminal is preferably continuous. That is, it is preferable that Chunk_D1, Chunk_D2 or Chunk_D2, Chunk_D3 be allocated to UE1. The transmitter determines a subcarrier included in the Chunk_D before or after allocating Chunk_D to the UE.

Since the transmitting side allocates a radio resource (eg, a subcarrier) to Chunk_D, Chunk_L may be allocated to the remaining radio resources. In other words, the transmitter configures a map for Chunk_L (S1102). The map for Chunk_L indicates which frequency-time resource a particular chunk is transmitted as shown in FIG. 8. That is, by performing the step of constructing the map, it is possible to determine the subcarriers included in the Chunk_L. As the number of subcarriers for Chunk_D1, Chunk_D2, and Chunk_D3 increases, the number of subcarriers for Chunk_L decreases. The number of subcarriers included in each Chunk_L may be constant. For example, Chunk_L1 is assigned # 2, # 4, # 5, # 6, # 8, # 9, # 10, and # 12 subcarriers (FIG. 8).

As described above, each chunk is allocated to at least one receiving side, and the transmitting side determines which receiving side to assign the Chunk_L to (S1103). In the example of FIG. 11, Chunk_L1 through Chunk_L4 are allocated to UE3, and Chunk_L5 through Chunk_L7 are allocated to UE4.

Control information according to the scheduling of S1101 to S1103 is transmitted to the terminal. However, the control information is more preferably transmitted through a separate path according to the information. According to the sixth embodiment, the receiving party to which the Chunk_D has been allocated receives a first identifier for notifying whether the Chunk_L or the Chunk_D has been allocated (S1105). One bit is sufficient for the first identifier. In addition, the receiving side further receives an index for distinguishing each chunk (S1106). For example, the receiving side to which Chunk_D is allocated, such as UE1, receives the first identifier that it has been allocated Chunk_D, and further receives the index information that it has been allocated Chunk_D1 and Chunk_D2. When the UE1 receives the information about the first identifier and the index information, the UE1 may know on which subcarrier the chunk allocated for itself is transmitted. If three Chunk_Ds are used, # 1, # 11, # 21, # 31, # 41, # 51, # 61, # 71 subcarriers are assigned to Chunk_D1, and # 7, # 17, # to Chunk_D2. 27, # 37, # 47, # 57, # 67, # 77 subcarriers are assigned, and # 3, # 13, # 23, # 33, # 43, # 53, # 63, # 73 subcarriers are assigned to Chunk_D3. The rule of assignment is because the transmitting and receiving side already knows. That is, the UE1 receives and decodes Chunk_D1 and Chunk_D2 through the first identifier and the index information (S1109).

Receiving side allocated Chunk_L like UE3, 4 is preferably notified of the number of Chunk_D used by the transmitting side through common signaling (S1104, S1110). If the receiving party to which the Chunk_L has been allocated further receives a first identifier (S1107) indicating an allocation scheme and an index (S1108) for distinguishing each Chunk_L, the receiving party may construct a map for the Chunk_L if not informed of the number of Chunk_D. Since there is no number, the number of Chunk_D is notified.

Suppose that the number of subcarriers in Chunk_D is S _D , the number of subcarriers in Chunk_L is S _L , the total number of subcarriers is S _T , the number of Chunk_D is N _D , the number of Chunk_L is N _L , and the sum of the two is N _T. do. In this case, the total number of subcarriers (S _T ) is the sum of the product of the number of each chunk and the number of subcarriers per chunk, so the relationship between N _D S _D + N _L S _L = S _T and the values S _{T ,} S initially determined _{From D} and S _L , the number of N _L can be obtained according to the number of N _D , and conversely, the number of N _D can be obtained according to the number of N _L.

The S _{T ,} S _D , and S _L may be determined at the beginning of communication, or may be transmitted in advance through a channel set separately on the transmission and reception side. Therefore, the S _{T ,} S _D , and S _L can be known through various methods. Even if only N _D (the number of chunk_D) or N _L (the number of chunk_L) is transmitted, the remaining values that are not transmitted can be obtained. As a result, even if the number of Chunk_L is notified instead of the number of Chunk_D, the receiver can accurately decode.

In addition, the present embodiment may transmit control information regarding scheduling to the receiver by improving the method of displaying index information without using the method of transmitting the allocation method information to a specific receiver as in the above-described method. Hereinafter, a method of transmitting control information about scheduling to the receiving side without separately transmitting the allocation method information will be described.

Hereinafter, a method of transmitting control information of the resource allocation method according to the fourth embodiment through the unified index of the seventh embodiment will be described.

If the index of the Chunk_D and the index of the Chunk_L constitute an unified index that does not overlap each other, and the transmitting side and the receiving side share the unified index configuration scheme, the transmitting side is connected to the first identifier or indicator D. There is no need to transmit the same allocation method information separately. Through this, communication resources can be saved.

For example, the number of Chunk_D allocated to a specific OFDM subframe is N _D , the number of Chunk_L is N _L , the sum of the two is N _T , and the index of Chunk_D is I _D , and the index of Chunk_L is I _L. . In this case, the I _D has a value from 1 to N _D , and the I _L has a value from 1 to N _L. The index of Chunk_D and the index of Chunk_L are distinguished through an integrated index called I _N. The unified index I _N may include information about the index of the Chunk_D and the index of Chunk_L by various methods. Hereinafter, an example will be described in which one unified index I _N includes both information on the index of Chunk_D and the index of Chunk_L. For example, according to a separate signaling or communication initial setting between the transmitting and receiving sides, the transmitting side includes information about the index of the Chunk_D in the front part of the unified index I _N and the other part of the Chunk_L in the other part. You can include information about the index. That is, in constructing the unified index (I _N ), if the index of Chunk_D is configured as I _N = I _D , and the index of Chunk_L is configured as I _N = I _L + N _D, then when 1 = I _N = N _D , _D = I _N and N _D + 1 = I _N = N _D + N _L is I _L = I _N -N _{D so} that I _D and I _L can be distinguished without allocation method information, respectively.

As another example, the transmitter may include information about the index of the Chunk_L in the front part of the unified index I _N and include information about the index of the Chunk_D in the remaining part. That is, in constructing the unified index (I _N ), if the index of Chunk_L is configured as I _N = I _L , and the index of Chunk_D is configured as I _N = I _D + N _{L and} is transmitted, 1 at I = I _N = N _{L L} = I _N and N _L +1 = I _N = N _L + N _D can be distinguished from I _D and I _L without the allocation scheme information, respectively, as I _D = I _N -N _L.

The unified index is an index including both of the indexes of the indexes of the Chunk_D and the indexes of the Chunk_L without overlapping, and there is no limitation in the method of configuring the unified index. However, as in the above-described examples, it is preferable that the index of Chunk_D and the index of Chunk_L are continuously arranged.

This embodiment omits the step (S1105) of transmitting the allocation method information through the above-described method, and improves the step (S1106) of transmitting the index for distinguishing the chunks, so that the receiving side transmits data to the transmitting side. There is a feature that transmits information that can be decoded.

When the indices for the Chunk_D are continuously given, the receiving side # 1, # 11, # 21, # 31, # 41, # 51, # 61 to Chunk_D1 through the number of Chunk_Ds used by the transmitting side. , # 71 subcarriers are assigned, # 7, # 17, # 27, # 37, # 47, # 57, # 67, # 77 subcarriers are assigned to Chunk_D2, and # 3, # 13, # 23 are assigned to Chunk_D3 , Subcarriers # 33, # 43, # 53, # 63, # 73 can be seen that. In the case of UE3, it is possible to know that the user has been assigned Chunk_L and Chunk_L1, Chunk_L2, Chunk_L3, and Chunk_L4 by receiving the unified index. In this manner, the terminal 3 can decode Chunk_L (S1112).

It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention. Accordingly, the above detailed description should not be construed as limited in every respect and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

The present invention has the following advantageous effects.

The present invention relates to an improvement of a subcarrier resource allocation scheme of a multi-carrier system. The combination of subcarriers constituting a chunk of a distributed allocation scheme and a zone allocation scheme is different. When used, the distributed allocation scheme has an advantageous effect of efficiently obtaining frequency diversity gain. In addition, the zone allocation scheme has an advantageous effect of obtaining user diversity gain.

Claims (26)

A communication system for transmitting data in subframe units including at least one OFDM symbol, Configuring at least one zone chunk comprising a plurality of subcarriers adjacent to each other in a frequency domain; Assigning the zone chunk to a particular frequency domain according to a distributed allocation method; And Allocating the zone chunks to the remaining areas except the allocated frequency domains according to a distributed allocation method. Radio resource allocation method in a multi-carrier system comprising a. The method of claim 1, The allocating according to the distributed allocation method may include: A method for allocating radio resources in a multi-carrier system, wherein at least one zone chunk for a particular user is allocated to a distributed frequency domain. The method of claim 2, The allocating according to the distributed allocation method may include: A radio resource allocation method in a multi-carrier system, characterized in that at least one zone chunk shared by a plurality of users is allocated to a distributed frequency domain. The method of claim 1, Assigning according to the zone allocation method, A method for allocating radio resources in a multi-carrier system, wherein at least one zone chunk for a particular user is allocated to adjacent frequency regions. The method of claim 1, Transmitting first index information indicating a frequency domain to which the zone chunk is allocated according to the distributed allocation method; And Transmitting second index information indicating a frequency domain to which the zone chunk is allocated according to the zone allocation method; Radio resource allocation method in a multi-carrier system, characterized in that it further comprises. The method of claim 5, Transmitting an indicator indicating which of the distributed allocation method and the zone allocation method has been applied; Radio resource allocation method in a multi-carrier system characterized in that it further comprises. The method of claim 5, Zone chunks corresponding to successive first index values are assigned to frequency domains not adjacent to each other, Zone chunks assigned to specific users by the distributed allocation method have first index values contiguous with each other. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 5, The zone chunk further comprises transmitting any one of a total number of information used in a distributed allocation scheme and a last index value of the first index value. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 5, Zone chunks corresponding to successive second index values are assigned to adjacent frequency domains, Zone chunks assigned to a particular user by the zone assignment method have second index values contiguous with each other. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 5, The first index information is characterized in that the smallest index value and the largest index value of the zone chunk by the distributed allocation method, The second index information is characterized in that the smallest index value and the largest index value of the zone chunk by the zone allocation method, Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 5, The first index information is characterized in that the information on the smallest index value of the zone chunk and the number of zone chunks used by the distributed allocation method, The second index information is characterized in that the information on the smallest index value of the zone chunk and the number of zone chunks used by the zone allocation method, Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 5, Transmitting information about the number of zone chunks according to the distributed allocation method. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 1, Transmitting a consolidated index indicative of said allocation method and zone chunk, The specific area of the unified index is first index information corresponding to the frequency area to which the area chunk is allocated according to the distributed allocation method. The remaining area of the unified index is second index information corresponding to the frequency area to which the area chunk is allocated according to the area allocation method. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 1, Zone chunks allocated according to the distributed allocation method, Including different subcarriers for a certain number of OFDM symbols Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 1, If the number of zone chunks by the distributed allocation method is below a certain threshold, Constructing at least one distributed chunk comprising a plurality of subcarriers that are not adjacent to each other in a frequency domain; Preferentially assigning the distributed chunks to a particular frequency domain; Allocating the zone chunk in a frequency domain to which the distributed chunk is not assigned Radio resource allocation method in a multi-carrier system further comprises. A communication system for transmitting data in subframe units including at least one OFDM symbol, Configuring at least one distributed chunk including a plurality of subcarriers that are not adjacent to each other in a frequency domain; Configure a plurality of zone chunks comprising a plurality of subcarriers transmitted over some contiguous frequency domain, Configuring the zone chunk including remaining subcarriers other than the subcarriers included in the distributed chunks; And And allocating the distributed chunk and the zone chunk to a specific user. The method of claim 16, And the zone chunk comprises a subcarrier corresponding to a preset frequency domain. The method of claim 16, The number of subcarriers included in the zone chunks is equal to each other. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 16, Transmitting information about the number of distributed chunks Radio resource allocation method in a multi-carrier system, characterized in that it further comprises. The method of claim 19, Information about the number of distributed chunks is transmitted to all of at least one receiving end to which the zone chunk is allocated. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 16, Transmitting information about the number of zone chunks Radio resource allocation method in a multi-carrier system, characterized in that it further comprises. The method of claim 21, Information about the number of zone chunks is transmitted to the receiving end allocated the zone chunks. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 16, Transmitting an indicator indicating whether the allocated chunk is the zone chunk or the distributed chunk to a receiving end to which the chunk is allocated; Radio resource allocation method in a multi-carrier system, characterized in that it further comprises. The method of claim 16, Transmitting index information representing the allocated chunk to a receiving end to which the chunk is allocated; Characterized in that it further comprises, The index information is a radio resource allocation method in a multi-carrier system, characterized in that the index value is sequentially assigned. The method of claim 24, A plurality of subcarriers included in the distributed chunk having a specific index value, Not adjacent to a plurality of subcarriers included in a chunk having a previous value or a next value of the specific index value. Radio resource allocation method in a multi-carrier system characterized in that. The method of claim 16, Transmitting a consolidated index representing the distributed chunk and the zone chunk, The specific area of the unified index is first index information indicating the distributed chunk, And the remaining area of the unified index is second index information indicating the zone chunk.

Images