KR101406320B1 - Method and apparatus for managing multicast resource - Google Patents

Abstract

A multicast resource management method, wherein a base station allocates a multicast resource to a multicast group. The base station generates a MAP IE including a multicast resource information and a transmission indicator indicating whether the multicast resource is divided, and then transmits the MAP IE to the multicast group.

Description

[0001] METHOD AND APPARATUS FOR MANAGING MULTICAST RESOURCE [

The present invention relates to a multicast resource management method and apparatus.

Multicast communication is used for group communication or the like that simultaneously provides the same service to a plurality of users. In the group communication, since the same downlink traffic is simultaneously transmitted to a plurality of users in a group performing group communication, a plurality of users participating in group communication with the base station for data transmission of the group communication can use a multicast connection.

A robust modulation and coding scheme (MCS) can be used to provide a reliable service regardless of the location of the user receiving the multicast service. However, robust modulation and coding techniques can efficiently provide services to a large number of users, but limited radio resources limit service.

SUMMARY OF THE INVENTION The present invention provides a multicast resource management method and apparatus capable of efficiently providing limited radio resources to a plurality of users.

According to one embodiment of the present invention, a method for managing multicast resources of a base station is provided. The multicast resource management method includes a step of allocating a multicast resource to a multicast group, a MAP information element including a multicast resource information and a transmission indicator indicating whether the multicast resource is divided, MAP IE), and transmitting the MAP IE to the multicast group

.

The transmission indicator may indicate which traffic among the divided traffic is transmitted through the multicast resource when the multicast resource is divided.

The transmission indicator having the first value indicates that the divided traffic is not transmitted, the transmission indicator having the second value indicates that the first traffic among the divided traffic is transmitted, and the transmission indicator having the third value indicates the transmission The indicator indicates that traffic from the second to the last of the divided traffic is to be transmitted and the transmission indicator having the fourth value indicates that the last traffic among the divided traffic is transmitted.

The MAP IE may further include an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which the allocation of the multicast resource is maintained.

The MAP IE excluding the transmission indicator may not be changed until the valid period expires.

The multicast resource management method may further include transmitting a next MAP IE including new allocation information of a multicast resource to the multicast group when the valid period expires.

According to another embodiment of the present invention, a multicast resource management method of a mobile station belonging to a multicast group is provided. The multicast resource management method includes receiving a MAP IE including a multicast resource information allocated to the multicast group and a transmission indicator indicating whether the multicast resource is divided from the base station, And identifying whether the multicast resource is divided through the multicast network.

The transmission indicator may indicate which traffic among the divided traffic is transmitted through the multicast resource when the multicast resource is divided.

The transmission indicator having the first value indicates that the divided traffic is not transmitted, the transmission indicator having the second value indicates that the first traffic among the divided traffic is transmitted, and the transmission indicator having the third value indicates the transmission The indicator indicates that traffic from the second to the last of the divided traffic is to be transmitted and the transmission indicator having the fourth value indicates that the last traffic among the divided traffic is transmitted.

The MAP IE may further include an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which the allocation of the multicast resource is maintained.

The MAP IE excluding the transmission indicator may not be changed until the valid period expires.

The multicast resource management method may further include receiving a next MAP IE including new allocation information of a multicast resource when the valid period expires.

According to another embodiment of the present invention, there is provided a multicast resource management apparatus including a resource management unit and a transmission unit. The resource management unit allocates a multicast resource to a multicast group, and generates a MAP IE including a multicast resource information and a transport indicator indicating whether the multicast resource is divided. The transmitting unit transmits the MAP IE to the multicast group.

The transmission indicator having the first value indicates that the divided traffic is not transmitted, the transmission indicator having the second value indicates that the first traffic among the divided traffic is transmitted, and the transmission indicator having the third value indicates the transmission The indicator indicates that traffic from the second to the last of the divided traffic is to be transmitted and the transmission indicator having the fourth value indicates that the last traffic among the divided traffic is transmitted.

The MAP IE may further include an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which the allocation of the multicast resource is maintained.

The MAP IE excluding the transmission indicator may not be changed until the valid period expires.

According to another embodiment of the present invention, there is provided a multicast resource management apparatus including a receiving unit and a control unit. The receiving unit receives a MAP IE including a multicast resource information allocated to a multicast group from a base station and a transmission indicator indicating whether the multicast resource is divided. The control unit identifies whether the multicast resource is divided through the transmission indicator.

The transmission indicator having the first value indicates that the divided traffic is not transmitted, the transmission indicator having the second value indicates that the first traffic among the divided traffic is transmitted, and the transmission indicator having the third value indicates the transmission The indicator indicates that traffic from the second to the last of the divided traffic is to be transmitted and the transmission indicator having the fourth value indicates that the last traffic among the divided traffic is transmitted.

The MAP IE may further include an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which the allocation of the multicast resource is maintained.

The MAP IE excluding the transmission indicator may not be changed until the valid period expires.

According to an embodiment of the present invention, when the multicast resource is divided according to the limited resources, it is possible to accurately inform the mobile station whether the traffic is divided along with the resource allocation information and which traffic is the divided traffic. Thus, when providing a reliable multicast service, limited resources can be efficiently utilized.

1 is a diagram illustrating a multicast communication system according to an embodiment of the present invention.
2 is a diagram illustrating a multicast communication system according to another embodiment of the present invention.
3 is a diagram illustrating a multicast communication system according to another embodiment of the present invention.
4 is a diagram illustrating a method of establishing a multicast connection according to an embodiment of the present invention.
5 is a flowchart of a multicast resource management method according to an embodiment of the present invention.
6 is a diagram illustrating an example of a multicast resource management method according to an embodiment of the present invention.
7 and 8 are block diagrams of a multicast resource management apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, a mobile station (MS) is referred to as a terminal, a mobile terminal (MT), an advanced mobile station (AMS), a high reliability mobile station (HR- A subscriber station (SS), a portable subscriber station (PSS), an access terminal (AT), a user equipment (UE) , HR-MS, SS, PSS, AT, UE, and the like.

Also, a base station (BS) is an advanced base station (ABS), a high reliability base station (HR-BS), a node B, an evolved node B, eNodeB), an access point (AP), a radio access station (RAS), a base transceiver station (BTS), a mobile multihop relay (MMR) (RS), a relay node (RN) serving as a base station, an advanced relay station (ARS) serving as a base station, a high reliability relay station (HR) A femto BS, a home Node B, a HNB, a pico BS, a metro BS, a micro BS, ), Etc., and may be all or part of an ABS, a Node B, an eNodeB, an AP, a RAS, a BTS, an MMR-BS, an RS, an RN, an ARS, It may include a negative feature.

1 is a diagram illustrating a multicast communication system according to an embodiment of the present invention.

1, a base station 110 includes a multicast group identifier (ID) assigned to a corresponding multicast group 120 to provide multicast communication to a multicast group 120 including a plurality of mobile stations, Lt; / RTI > The multicast group ID is uniquely allocated in the base station 110, has a finite size, and is used as an identifier for notifying the multicast group of the allocated resources. The different multicast groups 120, 130, and 140 have different multicast group IDs (MGID_A, MGID_B, MGID_C).

The base station 110 uses a flow identifier (FID) to distinguish the connection from the multicast group ID. The base station 110 may assign a FID to each multicast group ID to uniquely identify a connection, i. E. Service flow, within the multicast group. Since the FID is an identifier for identifying a signal or a traffic connection in a multicast group, a specific connection in the multicast group can be identified in the base station 110 by a combination of the multicast group ID and the FID. That is, the base station 110 uses the multicast group ID and the FID to provide the multicast service to the multicast group 120. At this time, the same FID (FID0 or FID1) may be used in the different multicast groups 120, 130 and 140.

2 is a diagram illustrating a multicast communication system according to another embodiment of the present invention.

Referring to FIG. 2, the base station 210 provides a multicast service to a multicast group 220 including a plurality of mobile stations using a multicast group ID. At this time, the multicast group ID is uniquely allocated and has a finite size to identify the connection of the multicast group, that is, the service flow. The multicast group ID may have a size larger than the multicast group ID described in FIG. 1 for the service flow identification as well as the multicast group. For example, the multicast group ID in Fig. 1 may be 12 bits, and the multicast group ID in Fig. 2 may be 16 bits.

Different multicast group IDs (MGID0, MGID1, MGID2, MGID3, MGID4, and MGID5) are used in different multicast groups 220, 230, Also, the multicast resource allocated to the multicast service can be notified to the multicast group through the multicast group ID.

3 is a diagram illustrating a multicast communication system according to another embodiment of the present invention.

3, in a group communication system according to an embodiment of the present invention, a multicast group zone is defined by a set of base stations including at least one base station, a multicast group zone is defined in a multicast group zone, ID is assigned. A multicast group ID having a unique value in the multicast group zone is allocated to the multicast group and the multicast service can be identified through the FID in the multicast group. That is, the multicast service can be identified in the multicast group zone through the multicast group ID and the FID. Alternatively, a multicast group ID having a unique value in the multicast group zone may be assigned to the multicast group, and the multicast service to be served in the multicast group zone may be identified through the multicast group ID.

Also, in the multicast group zone, the base station set uses the same multicast group ID and FID or the same multicast group ID to transmit data of an arbitrary service flow. Therefore, if the mobile station has already registered with the base station for the multicast service, the multicast service can be provided seamlessly without registering with other base stations even if the mobile station moves to another base station in the same multicast group zone. When the mobile station moves from a different multicast group zone to a base station cell providing the same multicast service, the mobile station can continue to receive the multicast service by updating parameters related to the multicast service.

When a multicast group zone is defined as a single base station, a single base station can use a multicast group ID for providing a multicast service independently from other base stations.

4 is a diagram illustrating a method of establishing a multicast connection according to an embodiment of the present invention.

4, the MS 41 transmits a registration request (REG-REQ) message, and the BS 42 transmits a registration response (REG-RSP) message in response to the REG- To the mobile station 41 (S410). In this way, the mobile station informs the base station 42 of the multicast transmission support through the REG-REQ message in order to discover the multicast service, and the base station 42 transmits the REG-REQ message to the corresponding mobile station 41 ).

When the mobile station 41 registers for multicast service reception, either the mobile station 41 or the base station 42 initiates a dynamic service addition (DSA) procedure for a multicast connection S420). One of the mobile station 41 and the base station 42 transmits a DSA-REQ message to another node and receives a DSA-RSP message from another node, thereby establishing a multicast connection.

At this time, the DSA-REQ and DSA-RSP messages include multicast parameters related to the multicast service. The multicast parameter includes the multicast group ID of the multicast group to which the service flow is added. The multicast parameter may further include an FID associated with the multicast group ID.

Also, when a multicast group zone is supported, the multicast parameter may further include a multicast group zone ID in which the corresponding service flow is valid. Through this multicast parameter, the mobile station 41 can add a service flow for multiservice initiation. Alternatively, the base station may periodically broadcast the multicast group zone ID through a broadcast message. If the multicast group zone is not locally overlapped (that is, the base station belongs to only one multicast group zone or a multicast group zone is not defined), the multiplexing of the DSA-REQ and DSA-RSP messages The cast parameter may not include the multicast group zone ID.

The mobile station 41 and the base station 42 may perform the multicast service capability exchange performed in the REQ-REQ / RSP exchange procedure S410 in the DSA-REQ / RSP exchange procedure S420.

After setting the service flow in this way, the mobile station 41 receives the downlink control channel including the multicast resource allocation information from the base station 42 (S430) Data is received (S440).

When the service flow needs to be changed during the multicast service, the mobile station 41 and the base station 42 may perform a dynamic service change (DSC) procedure. That is, when any one of the mobile station 41 and the base station 42 transmits a DSC-REQ message, the other node responds with a DSC-RSP message. At this time, the DSC-REQ message and the DSC-RSP message also include multicast parameters. The multicast parameter may include a previous multicast group ID and a new multicast group ID, or may include a previous multicast group ID and an FID, and a new multicast group ID and an FID. The multicast parameter may further include a new multicast group zone ID.

When terminating the multicast service, the mobile station 41 and the base station 42 may perform a dynamic service delete (DSD) procedure to delete the corresponding service flow. In this case, the multicast group can be terminated in the multicast group by using the multicast group ID in the DSD procedure. Also, the base station may terminate the multicast service itself using the multicast group zone ID in the DSD procedure. When any one of the mobile station 41 and the base station 42 transmits a DSD-REQ message, the other node responds with a DSD-RSP message.

As described above, according to an embodiment of the present invention, the mobile station and the base station check the multicast service supported by the multicast service capability exchange, and add the service flow for the multicast service through the DSx (DSA, DSC, DSD procedure) , Altered or deleted.

5 is a flowchart of a multicast resource management method according to an embodiment of the present invention.

5, the BS 52 continuously allocates a multicast resource to a multicast group for multicast communication (S510), and transmits a downlink control channel including multicast resource allocation information to the multicast group (S520). The downlink control channel may be an information element (IE) of a MAP. In this case, a new type of MAP IE, for example a high reliability (HR) -Multicast DL (downlink) MAP IE or a new type of advanced MAP (A-MAP) Multicast DL Assignment A-MAP IE can also be defined.

Meanwhile, the base station 52 may divide multicast resources to utilize limited radio resources. That is, the base station may divide the multicast traffic and transmit the multicast traffic through the divided multicast resource. In this case, the base station 52 includes a transmission indicator (TI) in the downlink control channel to inform whether the multicast resource is divided (S520). The transport indicator can indicate whether there is no traffic segmented according to its value, or if traffic is segmented, which traffic is the traffic segmented.

The mobile station 51 determines whether the corresponding MAP IE is a MAP IE corresponding to the multicast group to which the MAP IE belongs based on the received MAP IE (S530). Then, the mobile station 51 checks the allocated multicast resource through the multicast resource allocation information of the identified MAP IE, and if the traffic that is not divided into the corresponding resource is transmitted or the divided traffic is transmitted, (S540). Thereafter, the mobile station 51 receives the multicast traffic through the multicast resource (S550).

6 is a diagram illustrating an example of a multicast resource management method according to an embodiment of the present invention.

As shown in Fig. 6, the base station periodically (i. E., Continuously) assigns multicast resources at a predetermined number of frame intervals. At this time, a predetermined number of frame intervals corresponds to an allocation period. A plurality of frames, for example, four frames, may form one superframe, and one frame may include a plurality of subframes, for example, eight subframes. In this case, the base station can transmit the MAP IE to the sub-frame to which the multicast resource is allocated.

The MAP IE includes multicast resource information, allocation period and lifetime allocated for multicast communication. The MAP IE further includes a transport indicator (TI). The validity period means a period in which resources continuously allocated are maintained, and the resource allocation information is not changed until the validity period expires. After expiration of the validity period, the base station again allocates a persistent resource for multicast communication or releases a previously allocated resource, and then transmits a MAP IE including the information. At this time, the base station may transmit the next MAP IE in the frame of the frame number (N _frame ) satisfying Equation (1) or transmit the next MAP IE in the super frame of the super frame number (N _superframe ) satisfying Equation (2) .

[Equation 1]

N _frame modulo L + 1 = 0

&Quot; (2) "

N _superframe modulo L + 1 = 0

In Equations (1) and (2), L is a valid period.

Then, the mobile station can confirm the information of the resource that is continuously allocated only by decoding one MAP IE, so that power loss used by decoding the MAP IE can be reduced. Since the mobile station can know in advance the period in which the MAP IE is transmitted or the period in which the multicast burst is transmitted, the power saving effect can be enhanced when the mobile station enters a power saving mode such as sleep mode or idle mode. Also, since the mobile station can know the time to decode a new MAP IE through the valid period included in the MAP IE, even if the persistently allocated resource is changed, it can be correctly confirmed.

In another embodiment, the base station may transmit the same information as the previous allocation information in the MAP IE before expiration of the validity period. At this time, restriction can be made so that the allocation information can be changed / canceled only when the base station valid period expires. Accordingly, reception and decoding of unnecessary resource information of the mobile station can be reduced.

Table 1 shows an example of a transmission indicator according to an embodiment of the present invention.

The base station can set the value of the transmission indicator as shown in Table 1 to indicate whether additional traffic is to be transmitted before the allocation period.

When the multicast traffic is transmitted unpartitioned, the base station may set the value of the transmission indicator to "00 " to indicate the fact that there is no additional transmission, i.

In the case where the multicast data is divided into two, the base station sets the value of the transmission indicator of the downlink control channel corresponding to the firstly transmitted divided traffic to "01 " The value of the transmission indicator of the downlink control channel can be set to "11 ". Through the transmission indicator, the BS can indicate the fact that the multicast traffic is divided and which traffic among the divided traffic belongs to the downlink control channel.

When the multicast data is divided into three or more pieces, the base station sets the value of the transmission indicator of the downlink control channel corresponding to the first divided divided traffic to "01 " The value of the transmission indicator of the corresponding downlink control channel is set to "11 ", and the value of the transmission indicator of the downlink control channel corresponding to the divided traffic from the second to the last transmission is set to" 10 & . Through the transmission indicator, the base station can indicate the fact that the traffic is divided and which traffic among the divided traffic belongs to the downlink control channel.

value Explanation 0b00 None (no additional transmission) 0b01 First (first transmission) 0b10 Continue (subsequent transfer) 0b11 Last (no further transmissions)

The value of such a transmission indicator may be changed according to the divided state of the traffic each time the downlink control channel is transmitted. However, if the validity period does not expire, the downlink control channel excluding the value of the transmission indicator is not changed. When the valid period expires, the assignment in the downlink control channel can be changed or released.

In the example of FIG. 6, the multicast resource is continuously allocated with the allocation period of 2 and the valid period of 6, and then the multicast resource is continuously allocated with the allocation period of 4 and the valid period of 12, And the resource is released.

In the example of FIG. 6, when the allocation period is 2 and the valid period is 6, the multicast data is divided into three and transmitted. At this time, the transmission indicator (TI) of the MAP IE for the first transmitted divided data has a value of "01", and the transmission indicator (TI) of the MAP IE for the second transmitted divided data is "10 , And the transmission indicator (TI) of the MAP IE for the last transmitted segmented data has a value of "11 ".

In the example of FIG. 6, when the allocation period is 4 and the valid period is 12, the multicast data is transmitted without being divided. At this time, the transmission indicator (TI) of the MAP IE has a value of "00 ".

As described above, according to an embodiment of the present invention, when the multicast resource is divided according to the limited resources, it is possible to accurately inform the mobile station whether the traffic is divided along with the resource allocation information and which traffic is the divided traffic. Thus, when providing a reliable multicast service, limited resources can be efficiently utilized.

Various examples of the downlink control channel according to an embodiment of the present invention will now be described in detail with reference to Tables 2 to 6.

The MAP IE, for example the HR-Multicast DL MAP IE, includes multicast resource information and a subburst information element (IE), which includes an allocation period, a lifetime and a transmission indicator. At this time, the sub-burst IE may be HR_Multicast_DL_Subburst_IE, for example.

The multicast resource information may be an ID (Region ID) of a predefined region, or OFDMA symbol information and subchannel information. OFDMA symbol information includes an OFDMA symbol offset and a number of OFDMA symbols and the subchannel information includes a subchannel offset and a number of subchannels can do.

In addition, the HR-Multicast DL MAP IE uses extended-2 downlink interval usage code (DIUC) and extended-3 DIUC to indicate that the corresponding MAP IE is an HR-Multicast DL MAP IE. And may also include the length of the corresponding MAP IE.

The sub-burst IE may further include a persistent flag, an allocation flag, allocation region information, or MCS (modulation and coding scheme) level information. The persistence flag indicates whether the allocation is a persistent allocation, and the allocation flag indicates whether the resource is allocated or unallocated. The allocation region information indicates an allocation region in a region allocated by the MAP IE, and may include a slot offset and a duration. MCS level information can be provided through the DIUC. The sub-burst IE may further include information on the multicast connection, for example, a multicast group ID. The mobile station can identify the MAP corresponding to the multicast group to which the mobile station belongs through the multicast group ID.

The HR-Multicast DL MAP IE and the HR_Multicast_DL_Subburst_IE, which are examples of the MAP IE and the sub-burst IE, can be defined as shown in Table 2 and Table 3, for example.

Syntax Size (bit) Notes HR-Multicast DL MAP IE { Extended-2 DIUC 4 HR Multicast DL Map IE () = 0xF (Extended-3 DIUC) Length 8 Length in bytes Extended-3 DIUC 4 0x01 Region ID Indicator One 0: not use Region_ID
1: use Region_ID If (Region_ID use indicator == 0) { OFDMA symbol offset 8 Offset from the start of the DL subframe Subchannel offset 7 Number of OFDMA symbols 7 Number of subchannels 7 Rectangular subburst Indication One Indicates subburst allocations are time-first rectangular. The duration field in each subburst IE specifies the number of subchannels for each rectangular allocation. This is only valid for AMC allocations and all allocations with dedicated pilots. When this field is clear, the subbursts shall be allocated in the frequency-first manner and the duration field reverts to the default operation. Reserved 2 } else Region_ID 8 Index to the DL region defined in the DL region definition TLV in DCD } HR_Multicast_DL_Subburst_IE () variable Table 3 Padding variable Padding to byte for the unspecified portion of this IE (i.e., not including the first two fields, "Extended-2 DIUC" and "Length"); shall be set to 0. }

Syntax Size (bit) Notes HR_Multicast_DL_Subburst_IE () { N subburst 4 Number of subbursts in the 2D rectangular region is this field value plus 1. Resource shifting indicator One 0 = No Resource shifting
1 = Resource shifting For (j = 0; j <Number of subbursts; j ++) { Allocation Flag One 1 = allocate
0 = de-allocate Group Indicator One TDD mode: Reserved, set to 0.
Used for FDD / H-FDD case only; to indicate the group assignment of the MS (see 8.4.4.2 and 8.4.4.2.1)
0b0: Group # 1
0b1: Group # 2 If (Allocation Flag == 0) { // deallocate HR Multicast CID 16 If (Resource shifting indicator == 1) { Duration variable Duration in slots. OFDMA Frame duration dependent
7 bits - 2.5 ms frame
8 bits - 5 ms frame
9 bits - 10 ms frame
10 bits - 20 ms frame Slot Offset variable Indicates the start of this persistent allocation in
OFDMA slots, with respect to the lowest numbered
OFDM symbol and the lowest numbered subchannel in the region.
OFDMA Frame duration dependent
7 bits - 2.5 ms frame
8 bits - 5 ms frame
9 bits - 10 ms frame
10 bits - 20 ms frame } } else if (Allocation Flag == 1) { // allocate HR Multicast CID 16 Persistent Flag One 0 = Non-persistent
1 = Persistent if (Power boost per subburst == 1) { Boosting One 0b000: Normal (not boosted)
0b001: + 6dB
0b010: -6dB
0b011: + 9dB
0b100: + 3dB
0b101: -3dB
0b110: -9dB
0b111: -12 dB;
Note that if the Persistent flag is set, the boosting value applies to each of the persistent allocation } Duration variable Duration in slots. OFDMA Frame duration dependent
7 bits - 2.5 ms frame
8 bits - 5 ms frame
9 bits - 10 ms frame
10 bits - 20 ms frame Slot Offset variable Indicates the start of this persistent allocation in
OFDMA slots, with respect to the lowest numbered
OFDM symbol and the lowest numbered subchannel in the region.
OFDMA Frame duration dependent
7 bits - 2.5 ms frame
8 bits - 5 ms frame
9 bits - 10 ms frame
10 bits - 20 ms frame If (Persistent Flag == 1) { Allocation Period (ap) 5 Period of the persistent allocation is this field
value plus 1 (unit is frame) Lifetime (L) 4 Indicates the amount of time that the transmission has been performed. The next transmission of information is at the frame whose frame number, N _frame , satisfies the following condition.

N _frame modulo L + 1 = 0
} else Next allocation offset 5 5 LSBs of frame number and it indicates next allocation of the allocation of this field } DIUC 4 Repetition Coding Indication 2 0b00: No Repetition coding
0b01: Repetition coding of 2 used
0b10: Repetition coding of 4 used
0b11: Repetition coding of 6 used Transmission Indication (TI) 2 Indicates whether additional traffic is transmitted before allocation period
0b00: no (no additional transmission)
0b01: first (first transmission)
0b10: continue (more transmission)
0b11: last (no more transmission)
} } Padding variable Padding to nibble; shall be set to 0. }

Meanwhile, the BS may perform a HARQ DL MAP (HARQ DL MAP) used for resource allocation for hybrid automatic repeat request (HARQ) or a persistent HARQ DL MAP used for HAR resource allocation Described sub-burst IE (HR_Multicast_DL_Subburst_IE), and can use them for multicast communication. The HARQ DL MAP IE and the Persistent HARQ DL MAP IE may be defined as shown in Table 4 and Table 5, respectively.

Syntax Size (bit) Notes Persistent_HARQ_DL_MAP_IE () { Extended-2 DIUC 4 Persistent_HARQ_DL_MAP_IE = 0xD Length 8 Length in bytes RCID_Type 2 0b00: Normal CID
0b01: RCID11
0b10: RCID7
0b11: RCID3
For HR Multicast, RCID_Type is set to 0b00 and Normal CID is replaced by HR Multicast CID ACK Region Index One The index of the ACK region associated with all subbursts (excluding HR multicast DL burst) is defined in this Persistent HARQ DL MAP (FDD / H-FDD only) while (data_remains) { Region ID use indicator One 0: Region ID not used
1: Region ID used Change Indicator One 0: No change occurred
1: Change occurred if (Region ID use indicator == 0) { OFDMA Symbol offset 8 Subchannel offset 7 Number of OFDMA symbols 7 Number of subchannels 7 Rectangular subburst indications One Indicates subburst allocations are time-first rectangular. The duration field in each subburst IE specifies the number of subchannels for each rectangular allocation. The slot offset field in each subburst IE specifies the subchannel offset from the first subchannel for each rectangular allocation. When this field is clear, the subbursts shall be allocated in the frequency-first manner and the duration field reverts to the default operation } else { Region ID 8 Index to the DL region defined in the DL region definition
TLV in DCD } Power boost per subburst One Set to 1 to signal power boost per subburst. This field
shall be set to 0 if Rectangular subburst indication is set
to 0 if (Power boost per subburst == 0) { Boosting 3 0b000: Normal (not boosted)
0b001: + 6dB
0b010: -6dB
0b011: + 9dB
0b100: + 3dB
0b101: -3dB
0b110: -9dB
0b111: -12dB
Note that if the persistent flag is set, the boosting value
applies to each allocation instance of the persistent
allocation } Mode 4 Indicates the mode of this HARQ region
0b0000: Persistent DL Chase HARQ
0b0001: Persistent DL Incremental redundancy HARQ
for CTC
0b0010: Persistent DL Incremental redundancy HARQ
for Convolutional Code
0b0011: Persistent MIMO DL Chase HARQ
0b0100: Persistent MIMO DL IR HARQ
0b0101: Persistent MIMO DL IR HARQ for Convolutional
Code
0b0110: Persistent MIMO DL STC HARQ
0b0111: HR Multicast DL subburst
0b1000 to 0b1111: Reserved Subburst IE Length 8 Length, in nibbles, to indicate the size of the subburst IE
in this HARQ mode. The MS may skip DL HARQ
Subburst IE if it does not support the HARQ mode.
However, the MS shall decode the NACK Channel field
from each DL HARQ Subburst IE to determine the UL
ACK channel shall use for its DL HARQ burst if (Mode == 0b0000) { Persistent DL Chase HARQ subburst IE variable } elseif (Mode == 0b0001) { Persistent DL Incremental redundancy HARQ for CTC subburst IE variable } elseif (Mode == 0b0010) { Persistent DL Incremental redundancy HARQ for Convolutional Code variable } elseif (Mode == 0b0011) { Persistent MIMO DL Chase HARQ variable } elseif (Mode == 0b0100) { Persistent MIMO DL IR HARQ variable } elseif (Mode == 0b0101) { Persistent MIMO DL IR HARQ for Convolutional Code variable } elseif (Mode == 0b0110) { Persistent MIMO DL STC HARQ variable } elseif (Mode == 0b0111) { HR Multicast DL subburst IE variable Table 3 } } Padding variable Padding to byte for the unspecified portion of this IE
(ie, not including the first two fields, "Extended-2
DIUC "and" Length "); shall be set to 0. }

Syntax Size (bit) Notes HARQ_DL_MAP_IE () { Extended-2 DIUC 4 HARQ_DL_MAP_IE () = 0x7 Length 8 Length in bytes RCID_Type 2 0b00: Normal CID
0b01: RCID11
0b10: RCID7
0b11: RCID3
For HR Multicast, RCID_Type is set to 0b00 and Normal CID is replaced by HR Multicast CID ACK region index One The index of the ACK region associated with all subbursts (excluding HR multicast DL burst) is defined in this HARQ DL MAP IE (FDD / H-FDD only).
0: first ACK region
1: second ACK region
This bit shall be set to 0 for TDD mode. Reserved One While (data remains) { Boosting 3 0b000: Normal (not boosted)
0b001: + 6dB
0b010: -6dB
0b011: + 9dB
0b100: + 3dB
0b101: -3dB
0b110: -9dB
0b111: -12 dB; Region_ID use indicator 1 bit 0: not use Region_ID
1: use Region_ID If (Region_ID use indicator == 0) { OFDMA symbol offset 8 Offset from the start symbol of the DL subframe Subchannel offset 7 Number of OFDMA symbols 7 Number of subchannels 7 Rectangular subburst Indication One Indicates subburst allocations are time-first rectangular. The duration field in each subburst IE specifies the number of subchannels for each rectangular allocation. This is only valid for AMC allocations and all allocations with dedicated pilots. When this field is clear, the subbursts shall be allocated in the frequency-first manner and the duration field reverts to the default operation. Reserved 2 } else { Region_ID 8 Index to the DL region defined in the DL region definition TLV in DCD } Mode 4 Indicates the mode of this HARQ region:
0b0000: Chase HARQ
0b0001: Incremental redundancy HARQ for CTC
0b0010: Incremental redundancy HARQ for Convolutional Code 0b0011: MIMO Chase HARQ
0b0100: MIMO IR HARQ
0b0101: MIMO IR HARQ for Convolutional Code
0b0110: MIMO STC HARQ
0b0111: HR Multicast DL subburst
0b1000 - 0b1111: Reserved Subburst IE Length 8 Length, in nibbles, to indicate the size of the sub-burst IE in this HARQ mode. The MS may skip DL HARQ Subburst IE if it does not support the HARQ mode. However, the MS shall decode the ACK Channel field from each DL HARQ Subburst IE to determine the UL ACK channel for it to use for its DL HARQ burst. If (Mode == 0b0000) { DL_HARQ_Chase_subburst_IE () variable } else if (Mode == 0b0001) { DL_HARQ_IR_CTC_subburst_IE () variable } else if (Mode == 0b0010) { DL_HARQ_IR_CC_subburst_IE () variable } else if (Mode == 0b0011) { MIMO_DL_Chase_HARQ_subburst _IE () variable } else if (Mode == 0b0100) { MIMO_DL_IR_HARQ_subburst_IE () variable } else if (Mode == 0b0101) { MIMO_DL_IR_HARQ_for_CC_subburst_IE () variable } else if (Mode == 0b0110) { MIMO_DL_STC_HARQ_subburst_IE () variable } elseif (Mode == 0b0111) { HR Multicast DL subburst IE variable Table 3 } } Padding variable Padding to byte for the unspecified portion of this IE, i.e., including the first two fields, "Extended-2 DIUC" and "Length "; shall be set to 0 }

The fields not described in Tables 2 to 5 are defined, for example, in the IEEE Std 802.16-2012 standard and the description thereof will be omitted.

Next, multicast resource allocation information according to another embodiment of the present invention will be described in detail with reference to Table 6.

The base station may define a multicast allocation A-MAP IE to allocate multicast resources using the A-MAP, and the multicast allocation A-MAP IE may be, for example, an HR-Multicast DL Assignment A-MAP IE .

The multicast allocation A-MAP IE includes allocation period, validity period, transmission indicator, and multicast allocation information as described above. The multicast allocation information may include a resource index indicating the location and size of the multicast resource. The multicast allocation information may further include information (Isizeoffset) used for calculating a burst size index and a long TTI indicator indicating the number of subframes over which the allocated resources are spread.

Also, the multicast-assigned A-MAP IE may notify that the corresponding A-MAP IE indicates allocation of resources or indicates cancellation of allocation, without using a separate flag indicating allocation or deallocation of resources, as a value of the allocation period. For example, when the allocation period is set to "00 ", the corresponding A-MAP IE can instruct allocation cancellation.

Then, the base station generates a 16-bit cyclic redundancy check (CRC) based on the randomized sequence of the information bits of the multicast-assigned A-MAP IE, and after masking the 16-bit CRC with the CRC mask including the multicast group ID , The masked CRC can be attached to the multicast assignment A-MAP IE. The mobile station can then identify the multicast assignment A-MAP IE with a CRC mask that includes the multicast group ID to which it belongs. That is, the mobile station can identify the multicast-assigned A-MAP IE corresponding to the multicast group to which the mobile station belongs with the CRC mask.

The HR-Multicast DL Assignment A-MAP IE, which is an example of the multicast assignment A-MAP IE, can be defined as shown in Table 6.

Field Size (bits) Value / Description HR-Multicast_DL_Assignment_A-MAP_IE () { A-MAP IE Type 4 HR-Multicast DL Assignment A-MAP IE Allocation period 2 Period of persistent allocation of multicast resource.
If (Allocation Period == 0b00), it indicates the deallocation of persistent resource.
0b00: deallocation
0b01: 2 frames
0b10: 4 frames
0b11: 6 frames If (Allocation Period == 0b00) { Resource Index 11 5 MHz: 0 in first 2 MSB bits + 9 bits for resource index
10 MHz: 11 bits for resource index
20 MHz: 11 bits for resource index
Resource index includes location and allocation size. Long TTI Indicator One Indicates the number of AAI subframes spanned by the allocated resource.
0b0: 1 AAI subframe (default TTI)
0b1: 4 DL AAI subframe for FDD or all DL AAI subframes for TDD (long TTI) Reserved 22 } else if (Allocation Period! = 0b00) { Isizeoffset 5 Offset used to compute burst size index MEF 2 MIMO encoder format

0b00: SFBC
0b01: Vertical encoding
0b10: Multi-layer encoding
0b11: CDR If (MEF == 0b01) { Parameter for vertical encoding M _t 3 Number of streams in transmission M _t <= N _t
N _t : Number of transmit antennas at the HR-BS

0b000: 1 stream
0b001: 2streams
0b010: 3streams
0b011: 4streams
0b100: 5streams
0b101: 6streams
0b110: 7streams
0b111: 8streams Reserved One } else if (MEF == 0b10) { Parameters for multi-layer encoding Si 4 MU-MIMO, and the modulation constellation of paired user in the case of 2-stream transmission.

0b0000: 2 streams with PSI = stream1 and other modulation = QPSK
0b0001: 2 streams with PSI = stream1 and other modulation = 16QAM
0b0010: 2 streams with PSI = stream1 and other modulation = 64QAM
0b0011: 2 streams with PSI = stream1 and other modulation information not available
0b0100: 2 streams with PSI = stream2 and other modulation = QPSK
0b0101: 2 streams with PSI = stream2 and other modulation = 16QAM
0b0110: 2 streams with PSI = stream2 and other modulation = 64QAM
0b0111: 2 streams with PSI = stream2 and other modulation information not available
0b1000: 3 streams with PSI = stream1
0b1001: 3 streams with PSI = stream2
0b1010: 3 streams with PSI = stream3
0b1011: 4 streams with PSI = stream1
0b1100: 4 streams with PSI = stream2
0b1101: 4 streams with PSI = stream3
0b1110: 4 streams with PSI = stream4
0b1111: n / a } Resource Index 11 5 MHz: 0 in first 2 MSB bits + 9 bits for resource index
10 MHz: 11 bits for resource index
20 MHz: 11 bits for resource index
Resource index includes location and allocation size. Long TTI Indicator One Indicates the number of AAI subframes spanned by the allocated resource.
0b0: 1 AAI subframe (default TTI)
0b1: 4 DL AAI subframe for FDD or all DL AAI subframes for TDD (long TTI) Lifetime (L) 4 Indicates the time to transmit next HR-Multicast DL Assignment A-MAP and the information excluding Transmission Indication (TI) of this HR-Multicast DL Assignment A-MAP does not change during the allocation duration.
The next HR-Multicast DL Assignment A-MAP is at the superframe whose superframe number, N _superframe , satisfies the following condition.

N _superframe modulo L + 1 = 0 Transmission Indication (TI) 2 Indicates whether additional traffic is transmitted before allocation period
0b00: no (no additional transmission)
0b01: first (first transmission)
0b10: continue (more transmission)
0b11: last (no more transmission) Reserved 5 } }

The fields not described in Table 6 are defined, for example, in the IEEE Std 802.16.1-2012 standard and the description thereof will be omitted.

Next, a multicast resource management apparatus for performing a multicast resource management method according to an embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG.

7 and 8 are block diagrams of a multicast resource management apparatus according to an embodiment of the present invention.

Referring to FIG. 7, the multicast resource management apparatus 700 includes a resource management unit 710 and a transmission unit 720.

The resource management unit 710 allocates the multicast resource to the multicast group, and generates the MAP IE including the multicast resource allocation information, the allocation period, the valid period, and the transmission indicator. The transmitting unit 720 transmits the MAP IE as a multicast group.

The multicast resource management apparatus 700 may be included in a base station or may be a base station.

Next, a multicast resource allocation information receiving apparatus for receiving resource allocation information according to an embodiment of the present invention will be described with reference to FIG.

8, the multicast resource management apparatus 800 includes a receiving unit 810 and a control unit 820. [

The receiving unit 810 receives the MAP IE transmitted from the base station. At this time, the MAP IE includes allocation information, an allocation period, a valid period, and a transmission indicator of multicast resources allocated to the multicast group. The control unit 820 identifies whether the MAP IE is a MAP IE corresponding to the multicast group to which the MAP IE belongs based on the multicast group ID or the CRC mask, and identifies whether the allocated multicast resource is divided through the identified MAP IE.

The multicast resource management apparatus 800 may be included in a mobile station or may be a mobile station.

At least some functions of the multicast resource management method and apparatus according to the above-described embodiments of the present invention may be implemented in hardware or software combined with hardware. For example, a processor implemented as a central processing unit (CPU) or other chipset, microprocessor, or the like performs functions of a resource manager 710 or a controller 820, and a transceiver performs functions of a transmitter 720 ) Or the receiving unit 810. [0086]

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

Claims (20)

A method of managing a multicast resource of a base station,
Assigning a multicast resource to a multicast group,
Generating a MAP information element (MAP IE) including information on the multicast resource and a transmission indicator indicating whether the multicast resource is divided; and
Transmitting the MAP IE to the multicast group
And a multicast resource management method. The method of claim 1,
Wherein the transmission indicator indicates which traffic among the divided traffic is transmitted through the multicast resource when the multicast resource is divided. The method of claim 1,
The transmission indicator having the first value indicates that the divided traffic is not transmitted,
The transmission indicator having a second value indicates that the first traffic among the divided traffic is transmitted,
The transmission indicator having a third value indicates that traffic from the second to the last of the divided traffic is to be transmitted,
The transmission indicator having a fourth value indicates that the last traffic among the divided traffic is transmitted
Multicast resource management method. The method of claim 1,
Wherein the MAP IE further includes an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which allocation of the multicast resource is maintained. 5. The method of claim 4,
Wherein the MAP IE excluding the transmission indicator is not changed until the valid period expires. 5. The method of claim 4,
And transmitting a next MAP IE including new allocation information of a multicast resource to the multicast group when the valid period expires. A multicast resource management method for a mobile station belonging to a multicast group,
Receiving a MAP information element (MAP IE) including information on a multicast resource allocated to the multicast group from the base station and a transmission indicator indicating whether the multicast resource is divided; and
Identifying whether the multicast resource is divided through the transmission indicator
And a multicast resource management method. 8. The method of claim 7,
Wherein the transmission indicator indicates which traffic among the divided traffic is transmitted through the multicast resource when the multicast resource is divided. 8. The method of claim 7,
The transmission indicator having the first value indicates that the divided traffic is not transmitted,
The transmission indicator having a second value indicates that the first traffic among the divided traffic is transmitted,
The transmission indicator having a third value indicates that traffic from the second to the last of the divided traffic is to be transmitted,
The transmission indicator having a fourth value indicates that the last traffic among the divided traffic is transmitted
Multicast resource management method. 8. The method of claim 7,
Wherein the MAP IE further includes an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which allocation of the multicast resource is maintained. 11. The method of claim 10,
Wherein the MAP IE excluding the transmission indicator is not changed until the valid period expires. 11. The method of claim 10,
And when the validity period expires, receiving a next MAP IE including new allocation information of a multicast resource. A resource manager for allocating a multicast resource to a multicast group and generating a MAP information element (MAP IE) including a multicast resource information and a transport indicator for indicating whether the multicast resource is divided; And
A transmission unit for transmitting the MAP IE to the multicast group,
The multicast resource management apparatus comprising: The method of claim 13,
The transmission indicator having the first value indicates that the divided traffic is not transmitted,
The transmission indicator having a second value indicates that the first traffic among the divided traffic is transmitted,
The transmission indicator having a third value indicates that traffic from the second to the last of the divided traffic is to be transmitted,
The transmission indicator having a fourth value indicates that the last traffic among the divided traffic is transmitted
Multicast resource management device. The method of claim 13,
Wherein the MAP IE further comprises an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which allocation of the multicast resource is maintained. 16. The method of claim 15,
Wherein the MAP IE excluding the transmission indicator is not changed until the valid period expires. A receiving unit for receiving a MAP information element (MAP IE) including information on multicast resources allocated to a multicast group from a base station and a transmission indicator indicating whether the multicast resource is divided; and
A control unit for identifying whether the multicast resource is divided through the transmission indicator,
The multicast resource management apparatus comprising: The method of claim 17,
The transmission indicator having the first value indicates that the divided traffic is not transmitted,
The transmission indicator having a second value indicates that the first traffic among the divided traffic is transmitted,
The transmission indicator having a third value indicates that traffic from the second to the last of the divided traffic is to be transmitted,
The transmission indicator having a fourth value indicates that the last traffic among the divided traffic is transmitted
Multicast resource management device. The method of claim 17,
Wherein the MAP IE further comprises an allocation period indicating a period in which the multicast resource is allocated and an expiration period in which allocation of the multicast resource is maintained. 20. The method of claim 19,
Wherein the MAP IE excluding the transmission indicator is not changed until the valid period expires.

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