JP2011151499A - Method and apparatus allocation in mimo-ofdm system, and radio resource - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio resource allocation method or the like that fully maintains the improved level of throughput of a MIMO-OFDM system while keeping fairness among a plurality of users in the MIMO-OFDM system. <P>SOLUTION: The radio resource allocation method is a method for allocating radio resources to each of a plurality of users in a MIMO-OFDM system. In the method configured as follows, at first, a plurality of radio resource blocks are sorted in the order of higher signal-to-interference noise ratios (SINR) regarding each of the plurality of users. Subsequently, the plurality of radio resource blocks of the plurality of users are grouped into a plurality of groups. Then, radio resources are allocated to the plurality of groups. Here, the radio resource allocation is performed preferentially from the radio resource block having a higher signal-to-interference noise ratio about each of the plurality of groups obtained by the grouping. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radio resource allocation method and radio resource allocation apparatus in a MIMO-OFDM system, and more particularly to a radio resource allocation method and radio resource allocation apparatus for allocating radio resources to each of a plurality of users in a MIMO-OFDM system. About.

  In MIMO (Multi Input Multi Output), a plurality of antennas are used to transmit and receive data via radio. With MIMO, the amount of communication per unit time can be increased.

  Further, as a wireless communication system, OFDM (Orthogonal Frequency Division Multiplexing access) and TDMA (Time Division Multiple Access) are known. OFDMA and TDMA are communication methods for increasing the spectrum (frequency band) utilization efficiency. In OFDMA, spectrum utilization efficiency is improved by sharing a subchannel among a plurality of user terminals.

  A MIMO-OFDMA / TDMA system in which the above-described MIMO and OFDMA / TDMA are combined is known (for example, see Patent Document 1). In this MIMO-OFDMA / TDMA system, a base station (BS) needs to allocate radio resources to a plurality of user terminals for both the uplink channel and the downlink channel. Here, the radio resources include power and subcarriers. A subcarrier is one of the components constituting a subchannel. In other words, a collection of a plurality of subcarriers is a subchannel.

  Here, in the MIMO-OFDMA / TDMA system, if radio resource allocation is not performed reliably, the spectrum utilization efficiency in each channel will decrease. Accordingly, there is a need to reliably allocate radio resources, increase spectrum utilization efficiency, and increase throughput. Therefore, in the conventional system, processing is performed so that a resource block (RB) is allocated to a user terminal having the best channel quality among all user terminals. This type of processing controls the system to always select a user terminal that is very close to the base station. Therefore, a user terminal that is far from the base station (that is, a user terminal with poor channel quality) misses information related to transmission-related changes or cannot obtain most of information related to transmission-related changes. Will be. That is, in the conventional system, throughput is increased by not considering user terminals that are far from the base station.

  On the other hand, it is also required that radio resources be allocated to user terminals that are remote from the base station. However, in order to consider user terminals far from the base station, it is necessary to grasp the data rate required by such user terminals and to secure time (scheduling) for allocating resource blocks. When such scheduling is performed, radio resources are also allocated to user terminals that are remote from the base station. As a result, resource blocks that can be allocated to user terminals with excellent channel quality are reduced, and system throughput is reduced.

  In other words, conventional systems cannot ensure fairness among user terminals without sacrificing throughput.

Special table 2008-501284

  Therefore, an object of the present invention is to provide a practical solution for allocating radio resources in a MIMO-OFDM system.

  Specifically, the present invention relates to a radio resource allocation method and radio resource allocation apparatus capable of sufficiently maintaining the high throughput of the system while maintaining fairness among a plurality of users in a MIMO-OFDM system. The purpose is to provide. Another object of the present invention is to provide a program (algorithm) for executing the radio resource allocation method by a computer such as a radio resource allocation apparatus, and a storage medium storing the program.

  A first aspect of the present invention relates to a radio resource allocation method. This radio resource allocation method is a method for allocating radio resources to each of a plurality of users in a MIMO-OFDM system.

  In this radio resource allocation method, a sorting step, a grouping step, and a radio resource allocation step are executed. Here, in the sorting step, for each of a plurality of users, a plurality of radio resource blocks are sorted in descending order of the signal-to-interference noise ratio (hereinafter also referred to as “SINR”) per unit time in the use frequency band. It is a step. The grouping step is a step of grouping a plurality of radio resource blocks of a plurality of users into a plurality of groups. The step of assigning radio resources is a step of assigning radio resources to a plurality of groups. The signal-to-interference and noise ratio (SINR) is the signal power and the desired signal among the signals that can be received by each user during the symbol period determined by the OFDM signal in the frequency band that can be used in the OFDM system. It represents the ratio of the power of other signals (interference waves and thermal noise), and represents the communication quality per unit time (especially the data rate).

  Then, in the step of assigning radio resources, radio resources are preferentially assigned from radio resource blocks having a high SINR value for each of a plurality of groups obtained by grouping.

  Thus, according to the first aspect, radio resources are allocated to radio resource blocks in consideration of the SINR value, so that the high throughput of the system can be sufficiently maintained. In addition, since grouping is performed, fairness among multiple users can be maintained.

  In a preferred aspect of the present invention, the grouping step groups a plurality of radio resource blocks of a plurality of users into a plurality of groups based on a plurality of threshold values set in SINR. In this case, the step of allocating the radio resources includes a step of selecting one group in a predetermined order from a plurality of groups, and a group selected in the step of selecting a group among radio resource block groups, A first allocation step of allocating radio resources to a radio resource block having the highest SINR value, a radio resource block group different from the radio resource block group of the first allocation step is selected, and the selected radio resource block group A second allocation step of allocating radio resources to a radio resource block having the highest SINR value. Thereby, the fairness of radio resource allocation can be reliably maintained.

  Further, in a more preferred aspect of the present invention, in the first allocation step, a radio resource block group corresponding to the first user having the largest average SINR value is selected from the radio resource block group. In the selected radio resource block group, radio resources are allocated to the radio resource block having the highest SINR value. In the subsequent second allocation step, a radio resource block group corresponding to the same first user as the first user is selected from the radio resource block group, and the radio resource having the highest SINR value among the selected radio resource block groups. Allocate radio resources to the block. As a result, radio resources can be allocated to users while taking into account the average height of SINR values.

  In a more preferred aspect of the present invention, the threshold value is associated with MCS (modulation and coding scheme) which is a combination of a modulation scheme and a coding rate. As a result, the throughput of the system can be reliably increased.

  Alternatively, in a preferred aspect of the present invention, the grouping step groups a plurality of radio resource blocks of a plurality of users into a plurality of groups based on a plurality of threshold values set in SINR. In this case, the step of allocating the radio resources includes a step of selecting one group from a plurality of groups in a predetermined order, a step of selecting one user from a plurality of users in a predetermined order, and a step of selecting a group. In the group selected in step 1, a radio resource block group corresponding to the user selected in the step of selecting a user is selected, and a radio resource block having the highest SINR value is selected from the selected radio resource block groups. And assigning resources. Thereby, the fairness of radio resource allocation can be reliably maintained.

  Further, in a more preferable aspect of the present invention, the threshold value is associated with MCS that is a combination of a modulation scheme and a coding rate. As a result, the throughput of the system can be reliably increased.

  Alternatively, in a more preferable aspect of the present invention, the grouping step groups a plurality of radio resource blocks of a plurality of users into a plurality of groups in units of users. In this case, the step of allocating the radio resource includes the step of selecting a group corresponding to the first user from a plurality of groups, and the radio resource block group constituting the group selected in the step of selecting the group. A first allocation step of allocating radio resources to a radio resource block having the highest value, and a radio resource block having the highest SINR value among radio resource block groups corresponding to a second user different from the first user And a second allocation step of allocating radio resources. Thereby, the fairness of radio resource allocation can be reliably maintained.

  Furthermore, in a more preferred aspect of the present invention, the average value of the SINR values of the plurality of radio resource blocks of the first user is larger than that of the second user. As a result, the high throughput of the system can be maintained more reliably.

  The second aspect of the present invention relates to a radio resource allocation device. The radio resource allocation device is a radio resource allocation device for allocating radio resources to each of a plurality of users in a MIMO-OFDM system, and for executing the radio resource allocation method according to the first aspect described above. It is. Therefore, also in this aspect, the same effect as that of the first aspect described above can be obtained.

  In addition, another aspect of the present invention relates to a program for executing the first aspect described above by a computer or the wireless resource allocation device according to the second aspect, and a recording medium storing the program. Also by these side surfaces, the same effects as the first side surface and the second side surface can be obtained.

  According to the present invention, in a MIMO-OFDM system, radio resources are allocated to a plurality of channels in units of blocks in consideration of a signal-to-interference and noise ratio (SINR) value. Thereby, in the MIMO-OFDM system, the high throughput of the system can be sufficiently maintained while maintaining fairness among a plurality of users.

FIG. 1 is a diagram schematically showing a configuration of a wireless communication system of the present invention. 2 (a) to 2 (b) are diagrams for explaining sorting of the resource block RB. FIG. 2 (a) shows an example of sorting related to the user 1, and FIG. An example of the sorting related to the user 2 is shown in FIG. FIG. 3 is a schematic diagram for explaining an example of a state after grouping is performed in the first aspect of the radio resource allocation method according to the present invention. FIG. 4 is a schematic diagram for explaining an example after assigning radio resources in the first aspect. 5 (a) and 5 (b) are schematic diagrams for explaining the second aspect of the radio resource allocation method according to the present invention. FIG. 5 (a) shows the radio resource allocation in the second aspect. An example after assignment is shown, and FIG. 5B shows a modification of FIG. FIG. 6 is a schematic diagram for explaining an example of a state after grouping is performed in the third aspect of the radio resource allocation method according to the present invention. FIG. 7 is a schematic diagram for explaining an example after assigning radio resources in the third mode.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the form described below is an example, and can be appropriately modified within a range obvious to those skilled in the art.

  FIG. 1 is a diagram schematically showing a configuration of a wireless communication system of the present invention.

  A wireless communication system 1 shown in FIG. 1 includes one base station 10 and a plurality of user terminals 20. In this aspect, the wireless communication system 1 is a MIMO-OFDM system that combines MIMO and OFDMA.

  The base station 10 includes a plurality of antennas and functions as a channel allocation device or a radio resource allocation device that allocates a channel to each of a plurality of (for example, three) user terminals 20 (also simply referred to as “users”). Specifically, the base station 10 enables radio communication between the user terminals 20 by assigning radio resources to the user terminals 20 (RRA). Radio resources include power and subchannel subcarriers. Radio resource allocation is performed for both the uplink channel and the downlink channel. In this aspect, eigen model transmission (EMT) is applied to MIMO data transmission, whereby user terminals are assigned to all corresponding eigen channels. In addition, although the base station 10 was mentioned as an example of a radio | wireless resource allocation apparatus, what kind of thing may be used as long as it is a device or a controller which can allocate electric power with respect to the user terminal 20. FIG.

  The user terminal 20 includes a plurality of antennas. The user terminal 20 may be any device capable of wireless communication, and may be, for example, a portable device (mobile terminal) or a stationary device. The user terminal 20 performs wireless communication (data transmission / reception) with another user terminal 20 using the channel assigned by the base station 20.

  Next, radio resource allocation by the base station 10 will be described. The allocation of radio resources is realized by reading and executing an algorithm (program) stored in the storage medium of the base station 10.

  First, let us consider a case (scenario) in which there are N usable data subchannels in a MIMO-OFDM system, and these subchannels are divided into B resource blocks RB.

Further, the following points (1) to (3) are considered as preconditions for the system.
(1) Information regarding the signal-to-interference and noise ratio (SINR) of each subchannel is known in both the wireless transmitter and the wireless receiver. Here, the signal-to-interference and noise ratio (SINR) is the desired signal power and the desired signal among the signals that can be received by each user during the symbol period determined by the OFDM signal in the frequency band that can be used in the OFDM system. It represents the power ratio of signals other than signals (interference waves and thermal noise), and represents the communication quality per unit time.
(2) The algorithm according to the present invention is used in the base station 10 (wireless transmitter).
(3) The mapping table shown in Table 1 below can be used in the wireless transmitter. In this mapping table, MCS1 is an optimal MCS (modulation and coding scheme) and maximizes the data rate, and MCS2 is the second-best MCS of the optimal MCS (that is, the second most suitable MCS). It is. As the value of the MCS index increases, the data rate decreases, and the MCS with the largest index (that is, MCSn) is the least suitable MCS, the data rate is the lowest, and the robustness is the strongest.

  And the allocation of the radio | wireless resource in the above scenarios can be performed according to any one aspect of the 1st aspect, the 2nd aspect, and the 3rd aspect which are demonstrated below, for example. Each aspect is common in that a plurality of radio resource blocks are grouped into a plurality of groups for each of a plurality of users. First, the first aspect will be described.

  In the first mode, first, for each of a plurality of users, a plurality of radio resource blocks are sorted in descending order of SINR (sorting). For example, if each of three user terminals (user 1, user 2, user 3) has six resource blocks RB, they are sorted as shown in FIGS. 2 (a) to 2 (c). 2A to 2C, the two indexes i and j in parentheses of each resource block RB indicate the numbers of resource blocks RB in the same frequency band as the former i, and the latter j indicates a user number.

  Subsequently, a plurality of radio resource blocks of a plurality of users are grouped into a plurality of groups (grouping). In this aspect, the grouping is performed based on a plurality of threshold values set in SINR. Here, the threshold is set to an SINR value corresponding to a suitable MCS (that is, a desired data rate) using the mapping table of Table 1. By associating the threshold value with the MCS in this way, it is possible to assign radio resources in consideration of the data rate. FIG. 3 shows a case where two threshold values set in SINR are threshold value A and threshold value B, whereby a plurality of radio resource blocks are divided into three groups (groups A, B, and C). ing.

  Then, radio resources are allocated. Specifically, for each of a plurality of groups obtained by grouping, radio resources are preferentially allocated from radio resource blocks having a high SINR. However, radio resources are allocated so that resource blocks RB of different users do not compete for the same frequency band (that is, resource block RB numbers i do not overlap).

  More specifically, as shown in FIG. 4, first, one group is selected from a plurality of groups in a predetermined order, and then a radio resource block group is selected in the selected group, and the selected radio is selected. A radio resource is allocated to a radio resource block having the highest SINR in the resource block group. Thereafter, another radio resource block group is selected, and radio resources are allocated to the radio resource block having the highest SINR among the selected radio resource block groups. By repeating such selection and assignment, radio resources are assigned.

  In the example shown in FIG. 4, in the first allocation, group A is selected, and the first user (user 1) having the largest SINR average value among a plurality of users from the radio resource block group corresponding to group A The radio resource block group corresponding to is selected, and the radio resource is allocated to the radio resource block (RB (1, 1)) having the highest SINR among the selected radio resource block group. In the second assignment, the radio resource block group corresponding to the first user is similarly selected from the radio resource block groups corresponding to the group B, and one of the selected radio resource block groups is selected. , Radio resources are allocated to the radio resource block (RB (2, 1)) having the highest SINR. Similarly, in the third allocation, radio resources are allocated from the group C to the radio resource block RB (6, 1). That is, in the example shown in FIG. 4, radio resources are preferentially allocated from a user with a high SINR average value.

  Thereafter, as shown in FIG. 4, in the groups A, B, and C, radio resources are allocated to the radio resource block having the highest SINR from the radio resource block group corresponding to the user 2. However, even if the radio resource block has the highest SINR, it is not selected if the number of the resource block RB is already used. For example, in the group C, the number 6 of the resource block RB has already been selected by the user 1, and therefore the number 2 of the next optimal (sub-optimal) resource block RB is determined by the user 2 (ie, RB (3 2)) is selected. Thereafter, in the groups A, B, and C, radio resources are allocated to radio resource blocks having the highest SINR from the radio resource block group corresponding to the user 3.

  By assigning radio resources as described above, radio resource blocks having a high SINR are sequentially selected from radio resource block groups corresponding to each user in each group so that resource block RB numbers do not overlap. Can do. That is, according to the first aspect, radio resource blocks can be selected fairly from each group, and radio resources can be allocated to the selected radio resource blocks. Further, by preferentially selecting a radio resource block having a high SINR, it is possible to suppress a decrease in system throughput. Furthermore, by assigning radio resources preferentially from a user with a large average SINR, it is possible to more reliably suppress a decrease in system throughput.

  In the example illustrated in FIG. 4, radio resources are preferentially allocated from users with a large SINR average value, but radio resources may be preferentially allocated from a user with a small SINR average value. In this case, the fairness of radio resource allocation can be ensured. Here, the average value of SINR is preferably calculated or obtained when sorting resource blocks RB.

  In the first aspect, when there is no resource block corresponding to the selected user in the selected group, the radio resource block selected from the radio resource block group corresponding to the other user of the group Alternatively, instead, a subsequent group may be selected and a radio resource may be assigned to a radio resource block selected from the group of radio resource blocks in that group.

  Subsequently, a second mode of radio resource allocation will be described.

  Also in the second mode, first, as in the first mode, for each of a plurality of users, a plurality of radio resource blocks are sorted in descending order of SINR (sorting). For example, if each of three user terminals (user 1, user 2, user 3) has six resource blocks RB, they are sorted as shown in FIGS. 2 (a) to 2 (c).

  Subsequently, a plurality of radio resource blocks of a plurality of users are grouped into a plurality of groups (grouping). In this aspect, the grouping is performed based on a plurality of threshold values set in SINR. Here, the threshold is set to an SINR value corresponding to a suitable MCS (that is, a desired data rate) using the mapping table of Table 1. By associating the threshold value with the MCS in this way, it is possible to assign radio resources in consideration of the data rate. In FIG. 5A, two threshold values set in SINR are threshold value A and threshold value B, whereby a plurality of radio resource blocks are divided into three groups (groups A, B, and C). It is shown.

  Then, radio resources are allocated. Specifically, for each of a plurality of groups obtained by grouping, radio resources are preferentially allocated from radio resource blocks having a high SINR. However, radio resources are allocated so that resource blocks RB of different users do not compete for the same frequency band (that is, resource block RB numbers i do not overlap).

  More specifically, as shown in FIG. 5A, first, one group is selected from a plurality of groups in a predetermined order, and a user is selected from a plurality of users in a predetermined order. Subsequently, in the selected group, a radio resource block group corresponding to the selected user is selected, and radio resources are allocated to the radio resource block having the highest SINR among the selected radio resource block groups. Thereafter, a radio resource block group corresponding to the selected user is selected in the next selected group, and radio resources are allocated to the radio resource block having the highest SINR among the selected radio resource block groups. By repeating such selection and assignment, radio resources are assigned. However, the difference from the first mode is that, in this mode, a user corresponding to a radio resource block group for selecting the radio resource block RB is predetermined for each group. In order to realize this, for example, a user table may be provided for each group, and a user may be selected from the user table in a predetermined order each time a group is selected. Here, the predetermined order is preferably set to follow a round ribbon method (brute force method).

  In the example shown in FIG. 5A, in the first allocation, group A is selected and a predetermined user (for example, user 1) is selected, and a radio resource block group corresponding to user 1 of group A is selected. Therefore, radio resources are allocated to the radio resource block (RB (1, 1)) having the highest SINR. In the second allocation, radio resources are allocated to a radio resource block (RB (2, 1)) having the highest SINR from a radio resource block group corresponding to a predetermined user (for example, user 1) in group B. . Similarly, in the third allocation, radio resources are allocated to the radio resource block RB (6, 2) from the radio resource block group corresponding to a predetermined user (for example, the user 2) in the group C. That is, in the example shown in FIG. 5A, radio resources are preferentially allocated from a predetermined user.

  After that, as shown in FIG. 5 (a), in group A, the radio resource block having the highest SINR from the radio resource block group corresponding to the user following the predetermined user (for example, user 2) is wirelessly transmitted. Resources are allocated, and thereafter, in the groups B and C, the radio resources corresponding to the radio resource block having the highest SINR from the radio resource block group corresponding to the user following the predetermined user (for example, the user 3). Is assigned. However, when there is no corresponding radio resource block, radio resources are not allocated.

  By assigning radio resources as described above, radio resource blocks having a high SINR can be sequentially selected from radio resource block groups corresponding to users selected in a predetermined order in each group. That is, according to the second aspect, a radio resource block can be selected fairly from each group, and a radio resource can be allocated to the selected radio resource block. Further, by preferentially selecting a radio resource block having a high SINR, it is possible to suppress a decrease in system throughput. Therefore, the first aspect described above corresponds to the case where the order of selecting the users is the same regardless of the group in this aspect, that is, the case where weighting is given to the users whose SINR average value is high.

  By the way, FIG. 5A shows an example of a round ribbon method. In the round ribbon system shown in FIG. 5A, in group A, users 1, 2, and 3 are in the order, in group B, in the order of users 1, 2, and 3, in group C, users 2, 3, and 1 In this order, radio resources are allocated. However, the round ribbon method is not limited to the example shown in FIG. For example, as shown in FIG. 5B, in group A, users 1, 2, 3 are in the order, in group B, in the order of users 2, 3, 1, and in group C, users 3, 1, 2, The round ribbon method in which radio resources are allocated in this order may be used. By adopting the round ribbon method in this way, in this aspect, it is possible to ensure the fairness of radio resource allocation.

  In the second aspect, when there is no resource block corresponding to the selected user in the selected group, the radio resource block selected from the radio resource block group corresponding to the other user of the group Alternatively, instead, a subsequent group may be selected and a radio resource may be assigned to a radio resource block selected from the group of radio resource blocks.

  Subsequently, a third mode of radio resource allocation will be described.

  In the third aspect, first, for each of a plurality of users, a plurality of radio resource blocks are sorted in descending order of SINR (sorting). For example, if each of three user terminals (user 1, user 2, user 3) has six resource blocks RB, they are sorted as shown in FIGS. 2 (a) to 2 (c).

  Subsequently, a plurality of radio resource blocks of a plurality of users are grouped into a plurality of groups (grouping). In this aspect, grouping is performed on a user basis. Furthermore, as shown in FIG. 6, it is preferable to rearrange the users in the order of the average SINR values (indicated by triangles) of the plurality of radio resource blocks RB of the users. The threshold is preferably set to an SINR value corresponding to an appropriate MCS (that is, a desired data rate) using the mapping table of Table 1, and in particular, the average value of the user's SINR is a group based on the threshold. It preferably belongs to one of a plurality of divided groups. Then, by associating the threshold value with the MCS, radio resources can be allocated in consideration of the data rate. In the example shown in FIG. 6, a plurality of resource blocks RB of user 1 constitute group A, and the average SINR value of user 1 constitutes one group grouped by threshold A. Similarly, the user 2 corresponds to the group B, and the user 3 corresponds to the group C.

  Then, radio resources are allocated. Specifically, for each of a plurality of groups obtained by grouping, radio resources are preferentially allocated from radio resource blocks having a high SINR. However, radio resources are allocated so that resource blocks RB of different users do not compete for the same frequency band (that is, resource block RB numbers i do not overlap).

  More specifically, as shown in FIG. 7, first, a group corresponding to a predetermined user (for example, a user having the largest SINR average value) is selected from a plurality of groups, and then the selected group is selected. A radio resource is allocated to a radio resource block having the highest SINR among the radio resource block groups to be configured. Thereafter, radio resources are allocated to the radio resource block having the highest SINR among the radio resource block groups constituting the next selected group. By repeating such selection and assignment, radio resources are assigned. The order in which the groups are selected is preferably the same as the order in which the average value of the SINR of the users is high.

  In the example shown in FIG. 7, in the first allocation, group A (that is, a group corresponding to user 1) is selected, and the radio resource block (RB (RB ( 1, 1)) radio resources are allocated. In the second allocation, radio resources are allocated to the radio resource block (RB (4, 2)) having the highest SINR from the radio resource block group constituting the group B (group corresponding to the user 2). In the third allocation, similarly, radio resources are allocated to the radio resource block RB (2, 3) from the radio resource block group constituting the group C (group corresponding to the user 3). That is, in the example shown in FIG. 7, radio resources are allocated in the order of users.

  Thereafter, as shown in FIG. 7, from the group of radio resource blocks constituting each group, to a radio resource block RB (for example, resource block RB (3, 1)) to which no radio resource is assigned in the order of the user. On the other hand, radio resources are allocated.

  By assigning radio resources as described above, radio resource blocks having a high SINR can be sequentially selected from a radio resource block group of users corresponding to each group. That is, according to the third aspect, a radio resource block can be selected fairly from each group, and a radio resource can be allocated to the selected radio resource block. Further, by preferentially selecting a radio resource block having a high SINR, it is possible to suppress a decrease in system throughput. Further, fairness can be further improved by preferentially selecting a group corresponding to a user having a large SINR average value.

  In addition, according to the first to third aspects described above, a plurality of radio resource blocks of a plurality of users are sorted, and it is only necessary to assign radio resources in a predetermined order. Can be simplified. In the first aspect and the third aspect described above, radio resources are allocated from user terminals having a high SINR average value. However, radio resources may be allocated from user terminals having a low SINR average value. .

  In each aspect described above, grouping is performed for a plurality of user terminals. However, when one user can handle a plurality of channels or a plurality of subcarriers, each channel or subcarrier is classified. Grouping may also be performed.

  The present invention can be suitably used in the field of wireless communication (for example, WPAN (Wireless Personal Area Network) defined in IEEE 802.15), in particular, MIMO / OFDMA. In particular, it can be suitably used to increase the throughput of all systems in a fixed bandwidth. In addition, the present invention is suitable for a next generation mobile communication system (for example, a WMAN (Wireless Metropolitan Area Network) defined in IEEE 802.16) and a WiMAX (worldwide interoperability access system). sell.

1 wireless communication system 10 base station
20 User terminal

Claims (9)

A radio resource allocation method for allocating radio resources to each of a plurality of users in a MIMO-OFDM system,
Sorting a plurality of radio resource blocks for each of the plurality of users in descending order of the signal-to-interference noise ratio value per unit time in the usage frequency band;
Grouping a plurality of radio resource blocks of the plurality of users into a plurality of groups;
Allocating radio resources to the plurality of groups;
Including
In the step of allocating the radio resource,
For each of the plurality of groups obtained by the grouping, the radio resource is preferentially assigned from a radio resource block having a high signal-to-interference and noise ratio value.
Radio resource allocation method. The grouping step includes:
Grouping a plurality of radio resource blocks of the plurality of users into a plurality of groups based on a plurality of threshold values set in the signal-to-interference and noise ratio;
The step of allocating the radio resource includes:
Selecting one group in a predetermined order from the plurality of groups;
A first allocation step of allocating a radio resource to a radio resource block having the highest signal-to-interference noise ratio value among the radio resource block group in the group selected in the step of selecting the group;
A radio resource block group different from the radio resource block group in the first assignment step is selected, and radio resources for the radio resource block having the highest signal-to-interference and noise ratio value among the selected radio resource block groups are selected. A second assigning step for assigning
including,
The radio resource allocation method according to claim 1. In the first allocation step,
From the radio resource block group, a radio resource block group corresponding to the first user having the largest average value of the signal-to-interference noise ratio among the plurality of users is selected, and the selected radio resource block group includes the Assign radio resources to the radio resource block with the highest signal-to-interference and noise ratio value.
In the second allocation step,
A radio resource block group corresponding to the first user is selected from the radio resource block group, and radio resources are assigned to the radio resource block having the highest signal-to-interference noise ratio value among the selected radio resource block groups. assign,
The radio | wireless resource allocation method of Claim 2. The threshold is associated with an MCS that is a combination of a modulation scheme and a coding rate.
The radio | wireless resource allocation method of Claim 2. The grouping step includes:
Grouping a plurality of radio resource blocks of the plurality of users into a plurality of groups based on a plurality of threshold values set in the signal-to-interference and noise ratio;
The step of allocating the radio resource includes:
Selecting one group in a predetermined order from the plurality of groups;
Selecting one user in a predetermined order from the plurality of users;
In the group selected in the step of selecting the group, a radio resource block group corresponding to the user selected in the step of selecting the user is selected, and the signal-to-interference noise ratio is selected from the selected radio resource block group. Assigning radio resources to the radio resource block having the highest value of
including,
The radio resource allocation method according to claim 1. The threshold is associated with an MCS that is a combination of a modulation scheme and a coding rate.
The radio | wireless resource allocation method of Claim 5. The grouping step includes:
A plurality of radio resource blocks of the plurality of users are grouped into a plurality of groups in units of users;
The step of allocating the radio resource includes:
Selecting a group corresponding to the first user from the plurality of groups;
A first allocating step of allocating a radio resource to a radio resource block having the highest signal-to-interference / noise ratio value among radio resource block groups constituting the group selected in the step of selecting the group;
A second allocating step of allocating a radio resource to a radio resource block having a highest signal-to-interference / noise ratio value among radio resource block groups corresponding to a second user different from the first user;
including,
The radio resource allocation method according to claim 1. The first user has an average value of the signal-to-interference and noise ratio values of a plurality of radio resource blocks larger than that of the second user.
The radio | wireless resource allocation method of Claim 7. In a MIMO-OFDM system, a radio resource allocation device for allocating radio resources to each of a plurality of users,
For each of the plurality of users, means for sorting the plurality of radio resource blocks in descending order of the value of the signal-to-interference noise ratio per unit time in the use frequency band;
Means for grouping a plurality of radio resource blocks of the plurality of users into a plurality of groups;
Means for allocating radio resources to the plurality of groups;
Including
The means for allocating the radio resource includes:
For each of the plurality of groups obtained by the grouping, the radio resource is preferentially allocated from a radio resource block having a high signal-to-interference / noise ratio value.
Radio resource allocation device.

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