KR20090043742A - Method and apparatus for supporting collaborate mimo in wireless communication system - Google Patents

Abstract

Disclosed are a method and apparatus for grouping CMIMO terminals and allocating resources for the grouped CMIMO terminals to support CMIMO in a wireless communication system. To this end, grouping a plurality of CMIMO terminals into a plurality of groups, determining a burst size and a burst allocation area for each individual group of the plurality of groups in the uplink burst area, and Allocating a burst for each CMIMO terminal of the respective group in the determined uplink burst region, and configuring an uplink map information element based on burst allocation information for the CMIMO terminals, and configuring the uplink map information element By providing a CMIMO support method comprising the step of creating an uplink map message using the CMIMO terminal to transmit to the CMIMO terminal, it can be grouped to an odd number of CMIMO terminals, it is possible to efficiently use resources to perform CMIMO This results in improved system performance and limited resources. You can make the most of it.

Description

Method and Apparatus for supporting Collaborate MIMO in Wireless Communication System

The present invention relates to a method and apparatus for supporting CMIMO in a wireless communication system, and more particularly, to a method and apparatus for grouping CMIMO terminals and allocating resources for the grouped CMIMO terminals in order to support CMIMO in a wireless communication system. It is about.

Recently, as the necessity of transmitting a large amount of data at high speed using a wireless channel is rapidly increasing, a wireless / high-speed data transmission system for supporting mobile Internet service in a mobile environment is being actively researched. Multiple input multiple output (MIMO) systems are emerging to support Internet services. This MIMO system is described further.

1 and 2 illustrate an overview of a general SISO system and a MIMO system.

As shown in FIG. 1, a single input single output (SISO) system uses a single antenna (RxAnt, TxAnt) on a receiving side and a transmitting side, for example, a base station having one antenna (RxAnt) and a base station. A signal is transmitted and received through one channel H formed between terminals having one antenna TxAnt. In this SISO system, multipath phenomena occur due to obstacles in the propagation paths such as hills, valleys, and pylons, causing problems due to fading. do.

MIMO (Multiple Input Multiple Output) system is a technology that transmits data through multiple paths by increasing the number of antennas of a base station and a terminal, and reduces interference by detecting signals received in each path at a receiving end, and in space-time diversity and Spatial multiplexing can improve transmission efficiency. For example, FIG. 2 illustrates a 2x2 MIMO system using a base station having two antennas RxAnt0 and RxAnt1 and a terminal having two antennas TxAnt0 and TxAnt1, as shown in FIG. Likewise, four channels, that is, the first channel H00, the second channel H01, between the first and second antennas RxAnt0 and RxAnt1 of the base station and the first and second antennas TxAnt0 and TxAnt1 of the terminal. The third channel H10 and the fourth channel H11 are formed. Such a MIMO system has a higher data rate by including a plurality of transmit and receive antennas, which is advantageous in that the capacity of the radio link is improved in comparison with the SISO system in the transmit and receive period. That is, in a multipath-rich environment, multiple orthogonal channels can be created between transceivers so that data for a single user can be transmitted over the air in parallel over orthogonal channels using the same bandwidth at the same time. High spectral efficiency is achieved.

However, in the uplink of the 2 × 2 MIMO system, as described above, two antennas must be present in each terminal, and thus, there are various difficulties, such as the power loss of the terminal and the complexity of the terminal hardware. Therefore, CMIMO has been studied to increase the transmission rate as in the conventional MIMO using a terminal having a simpler hardware structure and one antenna, and more efficient methods for performing such CMIMO are required.

The present invention was devised to meet the above demands, and an object of the present invention is to provide a method and apparatus for supporting and performing CMIMO in a wireless communication system.

Another object of the present invention is to provide a method and apparatus for simplifying the complexity of transmission scheduling for supporting and performing CMIMO in a wireless communication system.

Another object of the present invention is to provide a scheduling method and apparatus for efficiently allocating resources to paired terminals by optimally pairing CMIMO terminals for supporting and performing CMIMO in a wireless communication system.

For the above purpose, a method for supporting Collaborative MIMO (CMIMO) in a wireless communication system of one embodiment of the present invention includes: (a) grouping a plurality of CMIMO terminals into a plurality of groups; (b) determining a burst size and a burst allocation area for each individual group of the plurality of groups in the uplink burst area equally; (c) allocating a burst for each CMIMO terminal of the respective group in an uplink burst region determined for the individual group; And (d) configuring an uplink map information element based on burst allocation information for the CMIMO terminals, and creating an uplink map message using the uplink map information element and transmitting the uplink map message to the CMIMO terminals. Characterized in that.

In addition, the method for supporting CMIMO (Collaborative MIMO) in a wireless communication system according to another aspect of the present invention, (a) of the first group and the second group of CMIMO terminals of the uplink burst size for the first group And configures an uplink map message to allocate a burst allocation area identically to the second group and to assign bursts for CMIMO terminals in the first group and the second group in the allocated uplink burst area, respectively. Transmitting to the CMIMO terminals; And (b) receiving a data burst allocated to the uplink burst region from at least one CMIMO terminal among the CMIMO terminals according to the uplink map message.

In addition, a method for supporting Collaborative MIMO (CMIMO) in a wireless communication system according to another aspect of the present invention includes the steps of: (a) receiving a registration message including terminal information from a plurality of terminals, respectively; And (b) grouping the selected CMIMO terminals into a plurality of groups based on the terminal information, and constructing and transmitting an uplink map message to commonly use an uplink burst region for the grouped individual groups. It is characterized by.

On the other hand, the method for supporting Collaborative MIMO (CMIMO) in the wireless communication terminal of one embodiment of the present invention, the same burst size and burst for each group for the two CMIMO terminal groups each including at least two or more CMIMO terminals Receiving, from a base station, an uplink map message including allocation information for allocating a burst of each CMIMO terminal to have an area; And transmitting a data burst including pilots to the base station based on the uplink map message, wherein the uplink map message further includes pattern type indication information of the pilots for the CMIMO terminals. It features.

On the other hand, the apparatus supporting CMIMO (Collaborative MIMO) in the wireless communication system of one embodiment of the present invention, in the uplink burst region, the burst size and burst allocation region for the first group of the plurality of CMIMO terminals A scheduler configured to assign the same as the second group and to configure an uplink map message to allocate bursts for the CMIMO terminals in the first group and the second group, respectively; And transmitting means for transmitting the uplink map message to the CMIMO terminals.

According to the present invention, by grouping the CMIMO terminals into a plurality of groups (layers), one CMIMO terminal can be simultaneously paired with the plurality of CMIMO terminals, and a pairing algorithm of the CMIMO terminals can be simplified, and the odd number of CMIMO terminals can be simplified. There is an effect that can be paired with the terminal.

In addition, according to the present invention, by grouping the CMIMO terminals into a plurality of groups (layers) and differently assigning bursts of individual CMIMO terminals in the group according to channel quality, more resources can be efficiently used to perform CMIMO. This results in improved system performance and maximum utilization of limited resources.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and preferred embodiments. For reference, in the following description, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention are omitted. In addition, hereinafter, for convenience of description, two CMIMO capable terminals and one base station, which are representative examples of a collaborative MIMO (CMIMO) system, will be described as an example. However, the present invention can be applied to the case of a 4x4 CMIMO system and the like, and thus, the present invention is not necessarily limited to the 2x2 CMIMO system described above.

3 is a diagram illustrating an uplink Collaborative MIMO (CMIMO) system, illustrating an uplink CMIMO system performed between two mobile stations (Mobile Station / Portable Subscriber Station) and one base station (Base Station / Radio Access Station). will be. In brief, the first CMIMO terminal transmits data through different pilot patterns through the first transmission antenna TxAnt0 and the second CMIMO terminal through the second transmission antenna TxAnt1. Then, the signals of the first channel and the third channel transmitted from the first CMIMO terminal and the signals of the second channel and the fourth channel transmitted from the second CMIMO terminal are spatial multiplexed through the same subcarriers in different pilot patterns. The base station having the first and second reception antennas RxAnt0 and RxAnt1 receives the signals transmitted from the first terminal and the second terminal, respectively.

4 is a diagram illustrating a frame structure used in a portable Internet system supporting OFDMA.

Referring to FIG. 4, the frame is divided into a downlink frame for transmitting data from a base station to a terminal and an uplink frame for transmitting data from a terminal to a base station, and the downlink frame is a preamble (preamble). It consists of Preamble, FCH (Frame Control Header), DL Map (DL MAP), UL Map (UL MAP), and DL Burst. The UL frame consists of control symbols (ranging, ACK). , CQI) and UL bursts. Here, HARQ MAP and HARQ bursts may be selectively added to the downlink frame, or information about the HARQ burst may be recorded in the downlink map or the uplink map without adding the HARQ map. . In the frame of this structure, the downlink frame includes a preamble section, a partial usage of subchannels (PUSC) subchannel section, a full usage of subchannels (FUSC) subchannel section, and an adaptive modulation & coding (AMC) subchannel section. The uplink frame includes at least one of an uplink control symbol interval, a PUSC subchannel interval, and an AMC subchannel interval.

In the illustrated example, the preamble is used to provide time and frequency synchronization and cell information to users, and the FCH contains information for decoding frame information and downlink map (DL MAP), and downlink map (DL MAP). ) Includes information on whether DL Bursts transmitted from the base station are bursts for SISO or bursts for MIMO, data of which UE, and in which region within a frame. In addition, the uplink map (UL-MAP) includes information on uplink bursts (UL-Burst) to be transmitted by the terminals.

In the present invention, the base station records uplink burst allocation information in the uplink map using the uplink map information element for the frame, and the terminal receiving the frame decodes the uplink map and then the uplink in the next frame. The terminal transmits its own burst to the base station in the corresponding uplink burst size and burst allocation area according to the burst allocation information.

Hereinafter, a method of supporting CMIMO in a wireless communication system according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 5 is a diagram illustrating a method of supporting CMIMO in a wireless communication system according to an embodiment of the present invention, and illustrates a method of supporting CMIMO between a base station and a terminal.

Referring to FIG. 5, first, each of the terminals informs the base station of its capability in an SSBC Basic Capability Request (SSC-REQ) message, and the base station determines the basic capabilities of the terminals and the base station to determine the SBC-RSP ( The response is carried on the SS Basic Capability Response) message (S100).

Subsequently, upon receiving the SBC-RSP message from each terminal, the base station registers the corresponding terminal (S200). Here, registration means that the base station connects the terminals to the network and receives additional management CIDs from the terminals and switches the terminals to a manageable state. To this end, the terminals transmit a Registration Request (REG-REQ) message to the base station, and the base station responds using a Registration Response (REG-RSP) message. In this case, the REG-REQ message includes the above-described additional management CID, and the REQ-RSP message includes the authority for the UEs to deliver traffic to the communication network.

Next, the base station performs scheduling for data transmission to the terminals (S300). Here, the scheduling is to group the terminals for CMIMO, and to pair the terminals between the groups to determine the resources to be allocated to the paired terminals, the determination of the resource is the burst size and burst for each terminal in the uplink frame This means configuring an uplink map information element to designate an allocation area and allocate a pilot pattern. In particular, in the case of scheduling related to the present invention, the number of groups (layers) is determined to be plural, but the number of terminals for each group is arbitrarily determined, and the burst size for each of the plurality of groups is configured to be the same, and the terminals The burst size and the burst allocation area for each terminal are allocated to the burst area of the group to which the terminal belongs, and are allocated to each terminal according to parameters such as channel quality, path loss according to the position of the terminal, power allocation to the terminal, correlation, and the like. Different burst sizes. The scheduling will be described in more detail with reference to the accompanying drawings.

Subsequently, the base station loads the resource allocation information (for example, the burst size, the burst allocation region, and the pilot pattern, etc.) determined for each terminal according to the scheduling performed in step S300 on the uplink map and transmits them to the terminals (S400). ).

Subsequently, each of the terminals receives the frame and decodes the data into respective data, and then, in the uplink transmission section of the next frame, allocates synchronized data to the uplink burst as indicated by the uplink map and transmits the data to the base station. (S500-S600). At this time, terminals belonging to different groups transmit data together with pilots of different pilot patterns.

6 is a flowchart illustrating a scheduling method for supporting CMIMO in a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 6, first, in step S310, the base station searches for CMIMO terminals in a system environment in which SISO and MIMO are mixed with reference to basic capacities interchanged with terminals.

Then, in step S320, the base station obtains parameters for the discovered CMIMO terminals. Such parameters may include, for example, channel quality, path loss according to the location of the terminal, power allocated to the terminal, correlation, and the like.

Subsequently, in step S330, the base station groups the CMIMO terminals using the above-described parameters or a combination of parameters. For example, grouping using path loss information according to the location of the CMIMO terminal, grouping using the CINR information of the CMIMO terminal, grouping using the allocated power for the CMIMO terminal, or carrier to CINR (CNRI) through the CQI channel of the CMIMO terminal. Interference and Noise Ratio) or correlation between ranging channels of the discovered CMIMO terminals, correlation between uplink sounding channels of the CMIMO terminals, or correlation between pilots of the CMIMO terminals. It is possible to group, and it is also possible to group the CMIMO terminals in consideration of at least two parameters. In particular, when grouping by using the CINR information of the CMIMO terminal, the CINR information is sequentially divided into two groups in ascending order, and can be applied to the remaining parameters in this manner. Alternatively, the grouping may be arbitrarily performed without using the parameter.

Next, in step S340, the base station determines the burst size and the area allocated to the individual group. In this case, the base station determines the burst size according to the channel quality (eg, QoS information) of the groups, but determines the burst size and area allocated to the first group and the burst size and area allocated to the second group in the same manner. . This determination method will be described in more detail with reference to FIG. 7.

7 is a diagram for describing a method of determining a burst size and an area allocated to an individual group according to an embodiment of the present invention.

As shown in FIG. 7, the OFDMA frame includes a preamble, a frame control header (FCH), a downlink map (DL-MAP), an uplink map (UL-MAP), and a downlink burst in a downlink frame. Bursts, and consists of ranging, ACK and CQI, and UL bursts in the uplink frame. In this case, the uplink map (UL-MAP) includes information on uplink bursts (UL-Bursts) transmitted by the CMIMO terminals.

In the illustrated example, the base station is a plurality of uplink bursts (UL burst 1, UL burst 2, ..., UL burst N) for the uplink frame, the uplink burst region (UL burst 1, UL designated for CMIMO) The burst burst size and region for the first group and the second group are determined from burst 2, ..., UL burst K). In the following description, for example, it is assumed that a size and an area corresponding to UL burst 2 of FIG. 7 are determined, and the uplink burst 2 is in an uplink PUSC mode.

Referring back to FIG. 6, in step S350, the base station determines the burst size and area allocated to each of the grouped CMIMO terminals. For example, as shown in FIG. 7, the base station is to allocate bursts for the CMIMO terminals of the first group and the CMIMO terminals of the second group to an UL burst 2 region. 8 and 9, the burst size of each CMIMO terminal for each group is equally assigned to each other, or as shown in Figures 10 and 11, the burst size of each CMIMO terminal for each group according to the channel quality Assign it differently.

Hereinafter, a method of determining a burst size for each terminal in a group will be described in more detail with reference to the accompanying drawings.

As shown in FIG. 8 and FIG. 9, the base station allocates 36 slots for each group to the UL burst 2 region with the same size, or as shown in FIGS. 10 and 11, the channel. According to the quality, 32 slots for each group may be allocated to the UL burst 2 region in different sizes. Here, the one slot is composed of six tiles. In addition, the tile is a basic unit constituting the PUSC subchannel, and is composed of three OFDMA symbols x four subcarriers in the two-dimensional plane of the OFDMA symbol-subcarrier.

First, in FIG. 8, the base station allocates a burst corresponding to the same 12 slots of each terminal to the uplink burst 2 region determined in step S340 for the terminal a1, the terminal a2, and the terminal a3 of the first group. In addition, in FIG. 9, each terminal allocates a burst corresponding to the same nine slots to the uplink burst 2 region for the terminal b1, the terminal b2, the terminal b3, and the terminal b4 of the second group.

In this way, when the burst is allocated, the base station schedules pairing between nine tiles between the terminal a1 and the terminal b1 and pairs three tiles between the terminal a1 and the terminal b2. In addition, the base station schedules pairing between six tiles between the terminal a2 and the terminal b2, and pairs six tiles between the terminal a2 and the terminal b3. Also, the base station schedules pairing between three tiles between the terminal a3 and the terminal b3, and pairs the nine tiles between the terminal a3 and the terminal b4. The burst allocation information of the CMIMO terminals, for example, is included in an uplink map message through a MIMO UL Basic IE and transmitted to the terminal.

On the other hand, in FIG. 10, the base station allocates bursts to the uplink burst 2 region determined in step S340 for the terminal a1, the terminal a2, and the terminal a3 of the first group, and the terminal a1 having the best channel quality has 14 stations. The burst corresponding to the slot is allocated, the terminal a2 allocates the burst corresponding to 13 slots, and the terminal a3 having the worst channel environment in the first group allocates the burst corresponding to the nine slots.

In FIG. 11, the base station allocates a burst to the uplink burst 2 region for the terminal b1, the terminal b2, the terminal b3, and the terminal b4 of the second group, but the terminal b1 having the best channel environment corresponds to 13 slots. Terminal b2 allocates a burst corresponding to ten slots, terminal b3 allocates a burst corresponding to seven slots, and terminal b4 having the worst channel environment in the second group has six slots. Allocates a burst corresponding to.

In this way, when the burst is allocated, the base station schedules pairing of 13 tiles between the terminal a1 and the terminal b1, and pairing of one tile between the terminal a1 and the terminal b2. In addition, the base station schedules to pair nine tiles between the terminal a2 and the terminal b2, and pairs four tiles between the terminal a2 and the terminal b3. Also, the base station schedules pairing between three tiles between the terminal a3 and the terminal b3, and pairs six tiles between the terminal a3 and the terminal b4. As described above, the burst allocation information of the CMIMO UEs is included in an uplink map message through the MIMO UL Basic IE and transmitted to the UE.

In step S360 of FIG. 6 again, the base station allocates different pilot patterns for each group. That is, when the bursts of the CMIMO terminals of the first group and the CMIMO terminals of the second group are allocated to one UL burst 2 region, the pilot patterns are differently allocated to the groups. This allocation of pilot patterns can reduce the map size. Alternatively, the base station may allocate different pilot patterns for each terminal in each group without allocating different pilot patterns for each group. In this case, different pilot patterns should be allocated to two terminals allocated to the same burst region.

Meanwhile, in steps S370 to S380 of FIG. 6, the base station creates an uplink map information element using burst allocation information for each CMIMO terminal determined in steps S340 to S360, and uplink based on the uplink map information elements. Construct and send a link map message.

Hereinafter, for convenience of description, a case of allocating HARQ subburst to the uplink burst 2 region of FIG. 12 will be described as an example.

The base station is the "UL MAP IE", "Extended-2 UIUC dependent IE", "HARQ UL MAP IE", "UL HARQ Chase Subburst IE" and "Dedicated UL" as disclosed in Tables 1 to 5 below. Control IE ”to record burst information (HARQ subburst in the illustrated example) that the CMIMO terminal should allocate to the uplink frame.

TABLE 1

"UL MAP IE" prescribes allocation for uplink bandwidth. The uplink bandwidth allocation is defined as a block allocation having an absolute offset, or an allocation having an arbitrary duration in which slots of a relative or absolute slot offset value are a basic unit. Referring to Table 1, an Uplink Interval Usage Code (UIUC) is used to define an uplink access type and a burst type associated with the access. For example, UIUC is used for fast feedback (UIUC = 0), CDMA ranging, bandwidth request allocation (UIUC = 12) as well as PAPR / Safety area allocation (UIUC = 13) in the form of block allocation. Meanwhile, CDMA allocation (UIUC = 14) is used when allocating bandwidth to a subscriber CMIMO terminal requesting bandwidth using a CDMA request code, and indicates that the current IE is delivering special information (UIUC = 11, UIUC = 15). In particular, when the UIUC value is 11 in the "UL MAP IE" used in this embodiment, it means that "Extended-2 UIUC dependent IE" of Table 2, which is the current map information element, conveys special information.

TABLE 2

"UL MAP IE" calls "HARQ UL MAP IE" as shown in Table 3 through "Extended-2 UIUC dependent IE".

TABLE 3

"HARQ UL MAP IE" defines modes supported in HARQ, and is also used to indicate non-HARQ transmission, and defines at least one uplink HARQ subburst. Referring to Table 3, in the "HARQ UL MAP IE", the base station defines a mode used in the "HARQ UL MAP IE" using the "Mode" field, and if this mode value is 0b000, the mode is set to "Chase HARQ" mode. , 0b011 corresponds to the "MIMO Chase HARQ" mode. In particular, in the present embodiment, it is assumed that the "Chase HARQ" mode is used. In addition, the base station designates the number of HARQ subbursts to be allocated by the CMIMO terminal in the "UL MAP IE" using the "N sub Burst" field, and the "for" syntax for detailed definition of the corresponding HARQ subburst. Calls the "UL HARQ Chase Subburst IE" shown in Table 4 by this HARQ subburst number.

TABLE 4

"UL HARQ Chase Subburst IE" specifies in detail the chase combining method of HARQ subburst, which is a mode in which each CMIMO terminal is determined in "HARQ UL MAP IE" for CMIMO. For example, referring to Table 4, the base station indicates that new HARQ subburst allocation information is defined in the current information element by setting the "Dedicated UL Control Indicator" field to set (1) or reset (0) ( (3) indicates that the same HARQ subburst allocation information is defined (reset). Accordingly, when the base station sets the "Dedicated UL Control Indicator" field to set (1), the base station defines HARQ subburst allocation information in detail by using the "Dedicated UL Control IE" shown in Table 5 below. Table 5 below defines the number of groups (or the number of layers) and the pilot pattern to be allocated to each group. Meanwhile, in Table 4 shown, the "UIUC field" is used to define an uplink access type and a burst type associated with the access, and the "Duration field" defines an allocation period in units of OFDMA slots, and the "ACK Disable field". Indicates whether the base station responds. If the base station sets the ACK Disable field to set (1), the base station does not need to perform an ACK response to the HARQ subburst transmitted by the CMIMO terminal, and the CMIMO terminal also needs to retransmit the corresponding HARQ subburst. none.

TABLE 5

The base station transmits additional control information to each CMIMO terminal for each HQAR subburst using this "Dedicated UL Control IE". In Table 5, the "Num SDMA layers" field contains information on the number of groups (or layers), and the "Pilot pattern" field contains pilot pattern information allocated to each group.

Meanwhile, FIG. 12 is a diagram illustrating a method of configuring an uplink map for an OFDMA frame to support CMIMO according to an embodiment of the present invention. The uplink map information elements shown in Tables 1 to 5 above are uplinked. This shows an example of assigning to a frame.

Referring to FIG. 12, uplink HARQ subburst allocation information for each CMIMO terminal (divided by CID) in a first group and a second group is defined through a "HARQ UL MAP IE" in an uplink map of an OFDMA frame. Also, the transmission type of the HARQ subburst for each CMIMO terminal is recorded through the "UL HARQ Chase Subburst IE". Here, the "SDMA Control Info bit" field of "Dedicated UL Control IE" shown in Table 5 is used to distinguish the first or second group. In this case, in FIG. 12, the "UL HARQ Chase Subburst IE" corresponding to 371 and 373 includes the "SDMA Control Info bit" field, and the "UL HARQ Chase Subburst IE" corresponding to the reference numerals 372 and 374. The "SDMA Control Info bit" field is not included.

Recording to the uplink map using the map information elements shown in Tables 1 to 5 described above is merely an example for explaining the present invention, but is not necessarily limited thereto. For example, other map information elements "UL MAP IE", "Extended UIUC 2 dependent IE" and "MIMO UL Basic IE" may be modified, or other map information elements "UL MAP IE" and "Extended 2 UIUC IE". , And "MIMO UL Chase HARQ sub-burst IE" is modified to create an uplink map information element using burst allocation information for each CMIMO terminal determined in steps S340 to S360 according to the present invention. Information elements may be recorded in an uplink map.

By doing so, the base station can quickly find a suitable CMIMO partner by performing CMIMO even if the burst sizes for each CMIMO terminal are different, and padding or cutting to deliberately match the size of the burst allocated to the paired CMIMO terminals. Not doing so can reduce resource waste and reduce the complexity of the scheduling algorithm.

Hereinafter, a configuration of a base station for implementing CMIMO supporting methods in a wireless communication system according to an embodiment of the present invention. Since detailed operation principles of each component are described in detail with reference to FIGS. 3 to 12, redundant descriptions thereof will be omitted.

13 is a diagram illustrating a configuration of a base station for supporting CMIMO in a wireless communication system according to an embodiment of the present invention.

As shown in FIG. 13, the base station includes an interface 100, a band signal processing unit 200, a transmitter 300, a receiver 600, a scheduler 500, and an antenna 400. The base station supports TDD and may be divided into a reception path and a transmission path.

In the reception path, the receiver 600 receives one or more radio signals transmitted by the CMIMO terminals through the antenna 400 and converts the one or more radio signals into a baseband signal. For example, the receiver 600 removes and amplifies noise from the above-described signal for data reception of the base station, down-converts the amplified signal to a baseband signal, and digitizes the down-converted baseband signal. The band signal processor 200 performs demodulation, decoding, and error correction processes by extracting information or data bits from the digitized signal. The received information is transmitted to the adjacent wired / wireless network via the interface 100 or transmitted to other CMIMO terminals serviced by the base station.

In the transmission path, the interface 100 receives voice, data, or control information from a control station or a wireless network, and the band signal processor 200 encodes the voice, data, or control information and outputs the encoded information to the transmitter 300. do. The transmitter 300 modulates the encoded voice, data, or control information into a carrier signal having a desired transmission frequency or frequencies, amplifies the modulated carrier signal to a level suitable for transmission, and propagates to the air through the antenna 400. do.

On the other hand, the scheduler 500 controls the operation of the reception path and the transmission path and each component, the configuration for a CMIMO system according to an embodiment of the present invention is shown in FIG.

FIG. 14 is a diagram showing the detailed configuration of the scheduler of FIG. 13. As shown in FIG. 13, the CMIMO searching unit 510, the parameter obtaining unit 520, the CMIMO group unit 50, and the burst information are determined. The unit 540 includes a pilot pattern assigning unit 550, a map information element constructing unit 560, and a map constructing unit 570.

The CMIMO search unit 510 refers to basic capacity such as physical parameters, bandwidth allocation, and the like provided by the UEs, so that the CMIMO is searched for in a system environment in which SISO and MIMO are mixed. Search for possible CMIMO terminals.

The parameter obtaining unit 520 obtains information on the CMIMO terminals discovered by the CMIMO searching unit 510. The information on the CMIMO UEs includes path loss information, CINR information, allocated power, carrier to interference and noise ratio (CINR) through a CQI channel, correlation between ranging channels, and uplink sounding. For example, the correlation between channels or the correlation between pilots may be mentioned.

The CMIMO group unit 530 is information about CMIMO terminals obtained through the parameter acquisition unit 520, that is, path loss information, CINR information, allocation power, and CINR (Carrier to Interference and Noise Ratio) through the CQI channel. ), CMIMO terminals are grouped using a correlation between ranging channels, a correlation between uplink sounding channels, or a correlation between pilots. In particular, when grouping by using the CINR information of the CMIMO terminal, the CINR information is sequentially divided into two groups in ascending order, and can be applied to the remaining parameters in this manner. Alternatively, the grouping may be arbitrarily performed without using the parameter.

The burst information determiner 540 determines the burst size and area allocated to the individual groups grouped by the CMIMO group unit 530 according to the channel environment of the groups. After the burst size allocated to the region and the second group and the region are identically determined, the burst size of the CMIMO terminals for each group is divided and allocated differently according to the channel quality of each CMIMO terminal. Since the principle of determining the burst size and the burst allocation region for each CMIMO terminal has been described in detail with reference to FIGS. 8 to 11, the description thereof will be omitted.

The pilot pattern allocator 550 allocates different pilot patterns to the CMIMO terminals grouped by the CMIMO group unit 530 for each group, or for two terminals allocated to the same burst region among the uplink burst regions. Assign another pilot pattern.

The map information element constructing unit 560 creates an uplink map information element by using the burst allocation information for each CMIMO terminal determined by the burst information determining unit 540 and the pilot pattern assigning unit 550, and creates a map constructing unit ( 570 records the uplink map information elements created by the map information element constructing unit 560 in the uplink map. Since the creation of the uplink map information elements and the recording of the uplink map have been described in detail with reference to FIG. 12, the description thereof will be omitted.

As such, by grouping the CMIMO terminals into a plurality of groups (layers) and differently assigning bursts of individual CMIMO terminals in the group according to channel quality, one CMIMO terminal may be simultaneously paired with a plurality of CMIMO terminals. The pairing algorithm of the CMIMO terminal can be simplified and can be grouped into an odd number of CMIMO terminals. In addition, it is possible to efficiently use resources to perform CMIMO, thereby obtaining improved system performance, and making the most of limited resources.

Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features, The examples are to be understood in all respects as illustrative and not restrictive.

In addition, the scope of the present invention is specified by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are within the scope of the present invention. It should be interpreted as being included.

1 is a view for explaining the outline of a general SISO system.

2 is a view for explaining an outline of a general MIMO system.

3 illustrates an uplink Collaborative MIMO (CMIMO) system.

4 is a diagram illustrating a frame structure used in a portable Internet system supporting OFDMA.

5 is a view for explaining a method of supporting CMIMO in a wireless communication system according to an embodiment of the present invention.

6 is a flowchart illustrating a scheduling method for supporting CMIMO in a wireless communication system according to an embodiment of the present invention.

FIG. 7 illustrates a method of determining a burst size and an area allocated to an individual group according to an embodiment of the present invention. FIG.

8 is a diagram illustrating a method of allocating a magnitude of a burst to individual terminals of a first group according to an embodiment of the present invention.

9 is a diagram illustrating a method of allocating a burst size to individual terminals of a second group according to an embodiment of the present invention.

FIG. 10 is a diagram for describing a method of allocating a burst size to individual terminals of a first group according to another embodiment of the present invention; FIG.

11 is a diagram illustrating a method of allocating a burst size to individual terminals of a second group according to another embodiment of the present invention.

12 illustrates a method of configuring an uplink map for an OFDMA frame to support CMIMO according to an embodiment of the present invention.

FIG. 13 illustrates a configuration of a base station for supporting CMIMO in a wireless communication system according to an embodiment of the present invention. FIG.

14 is a diagram illustrating a detailed configuration of the scheduler of FIG. 13.

Explanation of symbols on the main parts of the drawings

510: CMIMO search unit 520: parameter acquisition unit

530: CMIMO group unit 540: Burst information determination unit

550: Pilot pattern assignment unit 560: Map information element component

570: map component

Claims (21)

As a method of supporting Collaborative MIMO (CMIMO) in a wireless communication system, (a) grouping a plurality of CMIMO terminals into a plurality of groups; (b) determining a burst size and a burst allocation area for each individual group of the plurality of groups in the uplink burst area equally; (c) allocating a burst for each CMIMO terminal of the respective group in an uplink burst region determined for the individual group; And (d) constructing an uplink map information element based on burst allocation information for the CMIMO terminals, and creating an uplink map message using the uplink map information element and transmitting the uplink map message to the CMIMO terminals. CMIMO support method, characterized in that. The method of claim 1, wherein step (a) comprises: And grouping the CMIMO terminals by using at least one of channel quality information, path loss information, CINR information, allocated power information, and correlation for the CMIMO terminals. The method of claim 1, wherein step (c) comprises: And allocating different pilot patterns on a per-group basis. The method of claim 1, wherein step (c) comprises: The CMIMO supporting method, characterized in that different pilot patterns are allocated to the CMIMO terminals allocated to the same burst region in the uplink burst region. The method according to any one of claims 1 to 4, wherein step (c) comprises: And each burst for the CMIMO terminals in the individual group is determined differently according to channel quality of the CMIMO terminals. As a method of supporting Collaborative MIMO (CMIMO) in a wireless communication system, (a) Among the CMIMO terminals of the first group and the second group, an uplink burst size and a burst allocation region for the first group are allocated in the same manner as the second group, and within the allocated uplink burst region Constructing and transmitting an uplink map message to the CMIMO terminals so as to allocate bursts for the CMIMO terminals in the first group and the second group, respectively; And and (b) receiving, from the at least one CMIMO terminal among the CMIMO terminals, a data burst allocated to the uplink burst region according to the uplink map message. According to claim 6, wherein step (a), CMIMO supporting method characterized in that the burst size for the CMIMO terminals belonging to the first group and the CMIMO terminals belonging to the second group are determined differently according to the channel quality of the CMIMO terminals. The method of claim 6 or 7, wherein the uplink map message of the step (a), And a pilot pattern type indication information for allocating different pilot patterns for the first group and the second group. The method of claim 6 or 7, wherein the uplink map message of the step (a), CMIMO supporting method, characterized in that it includes pilot pattern type indication information for allocating different pilot patterns for the CMIMO terminals allocated to the same burst region in the uplink burst region. As a method of supporting Collaborative MIMO (CMIMO) in a wireless communication system, (a) receiving registration messages containing terminal information from a plurality of terminals, respectively; And (b) grouping the selected CMIMO terminals into a plurality of groups based on the terminal information, and constructing and transmitting an uplink map message to commonly use an uplink burst region for the grouped individual groups; CMIMO support method, characterized in that. The method of claim 10, wherein step (b) comprises: And configuring and transmitting the uplink map message to differently allocate burst sizes of CMIMO terminals belonging to the respective groups. The method of claim 10 or 11, wherein step (b) comprises: And configuring and transmitting the uplink map message to allocate each of the plurality of groups in different pilot patterns. The method of claim 10 or 11, wherein step (b) comprises: And configuring and transmitting the uplink map message to allocate different pilot patterns to the CMIMO terminals allocated to the same burst region in the uplink burst region. A device supporting Collaborative MIMO (CMIMO) in a wireless communication system, In an uplink burst region, a burst size and a burst allocation region for a first group among a plurality of CMIMO terminals are allocated to be identical to a second group, and bursts for CMIMO terminals in the first group and the second group are allocated. A scheduler configured to configure an uplink map message to allocate each of the uplink map messages; And And transmitting means for transmitting the uplink map message to the CMIMO terminals. The method of claim 14, wherein the scheduler, A CMIMO group unit for grouping a plurality of CMIMO terminals into the first group and the second group; Determining a burst size and a burst allocation area allocated to the first group, and a burst size and a burst allocation area allocated to the second group are the same, and for each of the CMIMO terminals of the first group and the second group A burst information determiner for allocating a burst; A map information element constructing unit for creating an uplink map information element using burst allocation information for each CMIMO terminal determined by the burst information determining unit; And And a map constructing unit configured to construct an uplink map message using the created uplink map information elements. The method of claim 15, wherein the CMIMO group unit, And grouping based on at least one of channel quality information, path loss information, CINR information, allocation power information, and correlation of the CMIMO terminals. The apparatus of claim 15, wherein the burst information determiner comprises: And a burst size for the CMIMO terminals of the first group and the second group is differently allocated according to channel quality of each CMIMO terminal. The method according to any one of claims 15 to 17, wherein the scheduler, And a pilot pattern allocator configured to allocate different pilot patterns to the CMIMO terminals of the first group and the CMIMO terminals of the second group. The method according to any one of claims 15 to 17, wherein the scheduler, And a pilot pattern allocator for allocating different pilot patterns to the CMIMO terminals allocated to the same burst region in the uplink burst region. A method for supporting Collaborative MIMO (CMIMO) in a wireless communication terminal, An uplink map message including allocation information for allocating a burst of each CMIMO terminal to have the same burst size and burst area for each group for two CMIMO terminal groups each including at least two CMIMO terminals. Receiving from a base station; And Transmitting a data burst including pilots to the base station based on the uplink map message, The uplink map message, CMIMO support method further comprises the pattern type indication information of the pilots for the CMIMO terminals. The method of claim 20, wherein the CMIMO terminal groups, CMIMO support method characterized in that the grouping based on at least one of channel quality information, path loss information, CINR information, allocated power information, or correlation of each CMIMO terminal.

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