CN1998259B - Supporting idle mode of mobile station in wireless access system - Google Patents

Abstract

The present invention discloses a method for supporting a mobile station in an idle mode in a wireless communication system using a paging controller, comprising: entering an idle mode by the mobile station; receiving a paging command from base stations in the same paging group, the paging command including a paging command action code related to performing ranging while the mobile station is in an idle mode to verify availability of the mobile station with respect to at least one of the base stations in the paging group, wherein the paging command is generated from the base stations in response to a paging announcement from the paging controller; and exiting the idle mode and establishing communication with one of the plurality of base stations, wherein the plurality of base stations in the same paging group receive the idle mode existing state from the paging controller.

Description

Supporting idle mode for mobile stations in wireless access systems

technical field

The present invention relates to a wireless access system, and in particular, to an idle mode of a mobile station in a wireless access system.

Background technique

Broadband wireless access systems typically support idle modes to minimize the power consumption of mobile subscriber stations (MSS). During idle mode, the MSS does not perform a handover procedure when moving between base stations in the same paging area. Therefore, the MSS does not need to transmit uplink information for the handover procedure, which reduces the corresponding power consumption.

A paging area is defined as an area controlled by a number of base stations called paging groups. Each base station in the paging group has the same paging cycle (Paging_Cycle) and the same paging offset (Paging_Offset).

The MSS may request the base station to switch to idle mode. The base station then provides a paging message including its paging group ID, corresponding paging cycle and corresponding paging offset. The corresponding MSS can thus be switched to idle mode. During the idle mode, the MSS may determine whether to continue or terminate the idle mode based on the paging message provided by the base station on every paging cycle.

If traffic needs to be delivered by the MSS while in idle mode, the MSS can terminate the idle mode. For example, the MSS may be able to terminate idle mode by the BS. In addition, if the MSS moves to another paging area, or loses its synchronization while in idle mode, and cannot receive pages for a predetermined time, the MSS can terminate the idle mode.

When the MSS is in idle mode, the MSS normally receives periodic paging to ensure that it can move freely in the same paging area without performing a handover procedure.

During the process of configuring the paging area, backbone messages (paging group actions) are transmitted between base stations by wire. An exemplary paging group action backbone message is shown in Table 1.

[Table 1]

field size Notes message type 8 bits Sender BS ID 48 bits Base station unique identifier (same number as broadcast on DL-MAP message) Target BS ID 48 bits Base station unique identifier (same number as broadcast on DL-MAP message) timestamp 32 bit Number of milliseconds, due to midnight GMT (set to 0×TTTTTTT to ignore) action 4 Assign the target BS to the paging group Delete the target BS from the paging group Query (which paging group the target BS belongs to?) Information (the paging group to which the sender BS belongs) Num Records 4 Number of paging group ID records For(j=0; j<Num Records; j++){ Paging-group_ID 16 bits Paging group ID PAGING_CYCLE 16 bits The period during which paging messages are sent within the paging group PAGING_OFFSET 8 bits MSS paging offset parameter } security field TBD means of verifying this message CRC field 32 bit IEEE CRC-32

Paging Group Action Backbone messages are exchanged between base stations. Based on the content of the Action field (Action), the Paging Group Action Backbone message can be used for four purposes. The receiving base station (target BS) can be assigned (assigned) to a specific paging group (action=0). Alternatively, the target BS can be removed from a specific paging group (action=1). Alternatively, the target BS may be queried about the paging group to which the target BS belongs (action=2). Alternatively, the target BS can learn the paging group to which the transmitting base station (sender BS) belongs (action=3).

Since a base station can belong to one or more radio paging areas, the paging group action backbone message can contain information related to many paging groups. The base station can learn the paging cycle and offset used in each paging zone via the paging group action backbone message. In addition, base stations can be dynamically assigned to paging groups via paging group action backbone messages.

When transitioning the MSS to idle mode, the DREG_REQ message (one of the previous MAC messages) is used. The format of the DREG_REQ message is shown in Table 2.

[Table 2]

Sentence Structure size note DREG-REQ_Message_Format(){ Management message type = 29 8 bits Go to register request code 8 bits 0x00 = SS de-registration request from BS and network 0x01 = request MSS to de-register from serving BS and invite MSS to page Availability Mode 0x02-0xFF = reserved paging cycle request 16 bits It is valid only when the deregistration request code=0×01 Parameters of TLV encoding Variable }

The MSS can send a request to the serving base station by setting the de-registration request code of the DREG_REQ message to 0×01 and then sending the DREG_REQ message to the base station, and the MSS will switch to idle mode. This allows delivery of specific paging cycles.

The serving base station receives the DREG_REQ message and may respond to the request of the MSS via a regular DREG_CMD message. The format of the DREG_CMD message is shown in Table 3.

[table 3]

Sentence Structure size Notes DREG-CMD_Message_Format(){ Management message type = 29 8 bits action code 8 bits Parameters of TLV encoding Variable }

The serving base station may allow switching to idle mode via an action code (action code = 0x05). Alternatively, the serving base station may allow the MSS to request switching to idle mode after a certain duration (action code = 0x06). Alternatively, the serving base station may not allow the MSS to request a switch to idle mode until a DREG_CMD message (action code = 0x07) is transmitted at the serving base station.

Details of the action codes of the DREG_CMD message are shown in Table 4.

[Table 4]

action code action 0×00 SS will leave the current channel and try to access another channel 0×01 The SS will listen to the current channel, but will not be transmitted until a RES CMD message or a DREG_CMD with action code 0x00 is received 0×02 SS will listen to the current channel, but only transmit on the base, primary management and secondary management connections 0×03 SS will resume normal operation and can transmit on any of its active connections 0×04 The SS will terminate the current normal operation by means of the BS; the BS will only transmit this action code in response to any SS DREG-REQ 0×05 Require MSS to register from the service BS, and request to start MSS idle mode 0×06 After the given duration (REQ-duration), MSS can resend the DREG_REQ message 0×07 MSS will not resend DREG_REQ message, and will wait for DREG-CMD message 0×08-0×FF reserved

Base stations belonging to the same paging area may be able to share information on MSS switching to idle mode. Using this information, the serving BS can inform the MSS of the procedures performed in each paging cycle.

The paging announcement backbone message is shown in Table 5.

[table 5]

field size Notes message type 8 bits Sender BS ID 48 bits Base station unique identifier (same number as broadcast on DL-MAP message) Target BS ID 48 bits Set to 0×ffffff to ignore timestamp 32 bit Number of milliseconds, in midnight GMT (set to 0×ffffffff to ignore) NUM MSS 8 bits Number of MSS pages For(j=0; j<NUM MSS; j++){ MSS MAC address 48 bits PAGING_CYCLE 16 bits MSS paging cycle parameters PAGING_OFFSET 8 bits MSS paging offset parameters } security field TBD A device for validating this message CRC field 32 bits IEEE CRC-32

The paging announcement backbone message can be transmitted to all base stations belonging to the same paging area. The base station receiving the paging announcement backbone message performs paging by matching the MAC address of the MSS included in the message with the paging cycle and offset within the message.

Therefore, due to the paging announcement backbone message, all base stations belonging to a specific paging area can equally hold the MAC address of the MSS to call. Therefore, a specific MSS can receive its paging information every paging cycle unless the MSS leaves (leaves) the current paging area.

The format of the paging message MOB_PAG_ADV transmitted by each base station to the MSS in idle mode via paging is shown in Table 6. The paging message is transmitted to the MSS in broadcast format.

[Table 6]

field size note MOB_PAG-ADV_Message_Format()} Management Message Type = ? ? 8 bits Num_Paging Group ID 8 bits The number of paging group IDs in this message For(i=0; i<Num_Paging_Group_ID; I) { paging group ID 8 bits } For (j=0; j<Num_MACs; j++){ The number of MSS MAC addresses in the message can be determined from the length of the message (obtained in the normal MAC header) MSS MAC address hash 24 bits The hash (hash) is obtained by calculating CRC24 on the 48-bit MAC address of the MSS. The polynomial used for this calculation is 0x864CFB. action code 2 digits Paging action command to MSS 00 = no action required 01 = perform ranging to establish location and confirm message 10 = enter network 11 = reserved reserve 6 digits } }

The MSS receives the paging message and can determine whether to continue in idle mode (action code = 00), whether to perform ranging to establish location information updates (action code = 01), and/or whether to terminate idle mode to receive downlink Road traffic (action code = 10).

If the MSS needs to transmit traffic (uplink traffic occurs), the MSS can terminate the idle mode. If the MSS needs to receive traffic (downlink traffic occurs), the MSS can also terminate the idle mode. The MSS can also terminate the idle mode if the MSS cannot receive periodic pages due to leaving the current paging area or due to transmission problems.

Contents of the invention

The present invention is directed to supporting idle mode of a mobile station in a wireless access system, which substantially obviates one or more problems of the related art.

It is an object of the present invention to provide support for idle mode of a Mobile Subscriber Station (MSS) in a broadband wireless access system, wherein actions taken by the MSS in idle mode are indicated to minimize the power consumption of the wireless access system , and by which accurate operation in idle mode can be guaranteed.

In the following description, the additional advantages, purposes and characteristics of the present invention will be set forth to some extent, when referring to the following contents or can be learned from the practice of the present invention, these advantages, purposes and characteristics are to some extent It will become apparent to those of ordinary skill in the art. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages, and in accordance with the objects of the present invention, as embodied and broadly described herein, in one embodiment, a wireless communication system using a paging controller supports idle mode A method for a mobile station among them, comprising: receiving an idle mode response command from a first base station to enter the idle mode; entering the idle mode by the mobile station; receiving a paging command from at least one of a plurality of base stations in the same paging group, The paging command includes a paging command action code related to the mobile station performing re-entry into the network, wherein the paging command is generated from at least one of the plurality of base stations in response to a paging announcement, wherein when there is When downlink service data to be transmitted to the mobile station, the paging controller generates the paging notification to instruct the mobile station to perform network re-entry, wherein the paging notification includes a paging notification action code; ending the idle mode; When the mobile station moves into the area of the second base station in the paging group, and when the paging command action code indicates that the mobile station should enter the network, send a ranging request message to the second base station to re-enter the network; from the receiving a ranging response message by a second base station; and receiving downlink traffic data from the second base station, wherein the downlink traffic data has been transferred from the first base station to the second base station according to an instruction of the paging controller.

In another embodiment, a method for supporting idle mode through a network in a wireless communication system using a paging controller includes: a first base station receiving a request to enter the idle mode from a mobile station, wherein the first base station and the paging controller paging controller, which controls a plurality of base stations associated with a paging group; an idle mode response command transmitted from a first base station to a mobile station to allow idle mode; at least one transmits a paging command to the mobile station, the paging command includes a paging command action code, the paging command action code is related to the mobile station performing re-entry into the network, wherein the paging command is in response to a call from the paging controller A paging announcement is generated from at least one of the plurality of base stations, and when there is downlink traffic data to be transmitted to the mobile station, the paging announcement is generated by the paging controller to instruct the mobile station to perform network re-entry, wherein The paging announcement includes a paging announcement action code; when the mobile station moves into the area of the second base station in the paging group, and when the paging command action code indicates that the mobile station should enter the network, the second base station will send the mobile station a second base station from the mobile station. The station receives the ranging request message to re-enter the network; sends a ranging response message from the second base station to the mobile station; transmits downlink traffic data from the first base station to the second base station according to an instruction of the paging controller; and from the second base station The second base station sends downlink traffic data to the mobile station.

From the following detailed description in conjunction with the accompanying drawings, the above and other objects, features, methods and advantages of the present invention will become more clearly apparent. It is to be understood that both the foregoing general description and the following detailed description of the invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Description of drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.

FIG. 1 is a block diagram illustrating a paging group according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an idle mode process in accordance with an embodiment of the present invention.

FIG. 3 illustrates a schematic diagram of a procedure for terminating an idle mode when downlink traffic is to be transmitted to a mobile station according to an embodiment of the present invention.

FIG. 4 is a block diagram illustrating a wireless access system with a paging controller according to an embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a process for managing base stations within a paging group using a paging controller according to an embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating an idle mode activation process in a wireless access system with a paging controller according to an embodiment of the present invention.

FIG. 7 is a flowchart illustrating traffic occurrence in an idle mode mobile station in a wireless access system with a paging controller according to an embodiment of the present invention.

Detailed ways

Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

The invention may be used in the context of the IEEE 802 Standard for Broadband Wireless Access Systems. Alternatively, the invention may be used in the context of any type of wireless access system.

FIG. 1 is a block diagram illustrating a paging group according to an embodiment of the present invention.

Referring to FIG. 1, a paging group includes at least one base station (BS). Each BS belonging to the same paging group can transmit and/or receive information required for an idle mode in a mobile station (MS) via a backbone message. A mobile station is also known as a mobile subscriber station (MSS). Alternatively, information required for idle mode in the MS may be transmitted and/or received between BSs belonging to different paging groups via backbone messages.

FIG. 2 is a flowchart illustrating an idle mode process in accordance with an embodiment of the present invention.

Referring to FIG. 2, in order to allow the MSS to enter the idle mode, it is preferable to use a registration request message, such as, for example, a DREG_REQ message as a medium access controller (MAC) message, to request a switch to the idle mode from the base station (S21). An exemplary format of the DREG_REQ message is shown in Table 2.

Preferably, the MSS can request the base station to enter the idle mode by setting the deregistration request code of the DREG_REQ message to 0×01, for example. The MSS may then transmit a DREG_REQ message to the base station.

The base station receiving the DREG_REQ message (receiving base station) can preferably respond to the request of the MSS via a command message such as, for example, a DREG_CMD message (S22). An exemplary format of the DREG_CMD message is shown in Table 3.

Preferably, the receiving base station can allow the MSS to enter idle mode via an action code (eg, action code = 0x05). Alternatively, the receiving base station may preferably allow the MSS to request to enter idle mode after a specified duration of time via another action code (eg, action code = 0x06). Alternatively, the receiving base station may disallow the MSS to request to enter idle mode before the receiving base station transmits a DREG_CMD message via another Action Code (eg, Action Code = 0x07).

Exemplary details of action codes related to the DREG_CMD message are shown in Table 4.

In one embodiment, base stations belonging to the same paging area may preferably be able to share information about MSSs that have entered idle mode. Using this information, the base station can preferably inform the MSS what procedures the MSS needs to perform in each paging cycle. To share information among BSs, a backbone message, such as the paging announcement backbone message shown in Table 5, for example, may be used. The paging announcement backbone message can preferably be transmitted to all base stations belonging to the same paging area (S23).

In another embodiment, an Action Code can be added to the Paging Announcement Backbone message for instructing the MSS the necessary actions to be performed while in idle mode. Therefore, as in the example of Table 7 below, NUM MSS", "MSS MAC Address", "Paging Cycle (PAGING CYCLE)" and "Paging Offset (PAGINGOFFSET) " and other fields of the paging announcement backbone message can be changed. An exemplary paging announcement backbone message with an added action code for instructing the MSS is shown in Table 7 below.

[Table 7]

NUM MSS 8 bits The number of MSSs that require action For(j=0; j<NUMMSS; j++){ MSS MAC address 48 bits action code 3 digits 0 = Add MSS to paging list 1 = Remove MSS from paging list 2 = Perform ranging to establish location and confirm message 3 = Enter network 4 = Reserved 5 digits reserve }

In yet another embodiment, the "PAGING_CYCLE (16 bits)" and "PAGING_OFFSET (8 bits)" fields can be deleted from the paging announcement backbone message, as shown in Table 7 above, because the base stations belonging to the same paging area Each has the same paging cycle and paging offset. Therefore, instead of the paging cycle and paging offset fields, an action code (for example, a 3-bit action code) can be added to the paging announcement backbone message to indicate that a specific MSS is connected to a specific MSS via an action code (for example, action code=0). The relevant MAC address has been added to the paging list. Alternatively, the Action Code may indicate via another Action Code (eg, Action Code = 1) that the MAC address of a particular MSS has been removed from the paging list. Alternatively, the action code may indicate that ranging has been performed for location information update (eg, action code = 2). Alternatively, the action code may indicate that a re-registration procedure to the network has been performed after terminating the idle mode (eg, action code = 3).

A paging message format such as a MOB_PAG_ADV message transmitted from each base station to an MSS in idle mode via paging is shown in Table 6. The paging message is preferably transmittable to the MSS in a broadcast format.

The MSS may receive the paging message, and use an action code (e.g., action code=00) to determine (determine) whether to continue to remain in the idle mode, whether to perform ranging to establish a location information update (e.g., action code=01), and/or Whether to terminate idle mode to receive downlink traffic (eg Action Code = 10).

The serving base station can preferably allow a specific MSS to enter idle mode, and set the action code of the paging announcement backbone message to 0, for example, and then transmit the paging announcement backbone message to all base stations in the paging area of the serving base station (S23). Each base station in the paging area can receive the paging announcement backbone message and can store the MAC address of the corresponding MSS in the paging list. Then, the base station may transmit the MAC address via the paging message MOB-PAG_ADV in every paging cycle (S24).

The MSS can receive the paging message and preferably can determine to remain in idle mode. In doing so, radio resources can be saved by including in the paging message the MAC address of the MSS that requires specific actions, such as re-registration to the network, or ranging for location information updates. To include the MAC address, for example, the "MSS MAC Address Hash" and "Action Code" fields of the paging message MOB-PAG_ADV in Table 6 preferably may be changed to match those in Table 8.

[Table 8]

For(j=0; j<Num_MACs; j++){ MSS MAC address hash 24 bits action code 2 digits 00 = enter network 01 = perform ranging to establish position and confirm message 10-11 = reserved

If the MSS is forced to terminate the idle mode due to occurrence of downlink traffic, each base station may not know that the corresponding MSS belongs to a domain within the paging area of each base station. Each base station can therefore set the action code of the paging announcement backbone message to, for example, 3, and then transmit the paging announcement backbone message to other base stations in the same paging area.

Other base stations in each base station's paging area may receive the paging announcement backbone message and set the action code of the paging message to 00, for example. The other base stations may then transmit a paging message to all MSSs in the paging area to allow the corresponding MSSs to terminate the idle mode and perform procedures for re-registration to the network.

After the MSS has normally terminated its idle mode, each base station can set the action code of the paging announcement backbone message to 1, for example, and can then transmit the paging announcement backbone message to other base stations in the paging area. Therefore, it is preferable that the paging for the corresponding MSS can be stopped.

FIG. 3 illustrates a schematic diagram of a procedure for terminating an idle mode when downlink traffic is to be transmitted to a mobile station according to an embodiment of the present invention.

Referring to FIG. 3, since the base station may not know the domain to which the MSS in idle mode belongs, downlink traffic can preferably be delivered unconditionally to the base station (the first base station or the initial base station) that the MSS originally requested to switch to idle mode. ).

After an MSS allowed to enter idle mode by the first base station receives downlink traffic, the first base station may set an action code related to all base stations in the paging area of the first base station to eg 11. The first base station may then transmit a paging announcement backbone message (S31).

Each base station in the paging area of the first base station may receive the paging announcement backbone message and set the action code of the paging message MOB_PAG_ADV to 10, for example. The base station may then transmit the paging message to all MSSs in the paging area in a broadcast format (S32).

The corresponding MSS can receive the paging message and terminate the idle mode. The MSS may also request the second base station (current base station) in charge of the paging area to which the MSS belongs to re-register with the network (S33). Preferably, the second base station can know the base station ID of the first base station via a paging announcement message.

The second base station may receive the re-registration request and set the action flag of the MSS_Info_Request backbone message to eg 1. Preferably, the MSS_Info_Request backbone message can be transmitted between base stations by wire. The second base station may then transmit an MSS_Info_Request backbone message to the first base station to inform the first base station that the MSS has left the paging area (S34). An exemplary format of the MSS_Info_Request backbone message is shown in Table 9.

[Table 9]

field size Notes global head 152 bits For(j=0; j<Num Records; j++){ MSS Unique Identifier 48 bits 48-bit unique identifier used by MSS (as provided by MSS or by an I-am-host-of message) action tag 8 bits Request information MSS obtained from idle mode MSS has transitioned to another paging group } security field TBD means of verifying this message

The first base station may receive the MSS_Info_Request backbone message, and may notify all base stations within the paging area of the first base station that the MSS has terminated the idle mode and will be deleted from the paging list of each base station.

The first base station is preferably capable of delivering the MSS service via a data transfer message having the format shown in Table 10.

[Table 10]

field size note global head 152 bits length 8 bits Length in bytes of the MAC SDU including global header, MSS unique identifier and security fields MSS Unique Identifier 48 bits A 48-bit unique identifier used by the MSS upon initial network entry MAC SDUs Variable received data security field TBD means of verifying this message

Except when the MSS is forced to terminate its idle mode due to downlink traffic, if the idle mode of the MSS needs to be terminated, the MSS can preferably perform the idle mode termination procedure no later than the first base station requesting the MSS to end the idle mode via paging .

After finishing terminating the idle mode of the MSS, when the base station receives a request to re-register to the network from the MSS, the BS may set the action code of the Announce Backbone message to 1, for example. The base station may then transmit a paging announcement backbone message to all base stations belonging to the corresponding base station's paging area so that the corresponding MSS may be deleted from the respective paging lists.

FIG. 4 is a block diagram illustrating a wireless access system with a paging controller according to an embodiment of the present invention.

Referring to FIG. 4 , the paging controller performs a call to the MSSs in the base stations of one or more paging groups by transmitting and/or receiving the necessary information for idle mode support to and/or from the base stations. Idle mode control. That is, transmission and/or reception of information necessary for idle mode provision may be performed between base stations via the paging controller. The paging controller may be provided in a specific base station, or may be provided separately from the base station.

FIG. 5 is a schematic diagram illustrating a procedure for managing base stations within a paging group using a paging controller according to an embodiment of the present invention.

Referring to FIG. 5, the paging controller can control base stations belonging to each paging group using a backbone message. For example, using the action code of the paging group action request backbone message, the paging controller can assign a base station to a paging group (e.g., action code = 0000), remove a base station from a specific paging group (e.g., action code = 0001), request the paging information of the corresponding base station (for example, action code=0010), or notify the paging information of another base station (for example, action code=0011) (S51). An exemplary paging group action request message is shown in Table 11.

[Table 11]

Preferably, the base station receiving the paging group action request message can transmit the information necessary for the idle mode using the action code of the paging group action response message. The paging group action response message may be transmitted to the paging controller by the base station receiving the paging group action request message (S52). For example, the base station may transmit a response to the paging group action request message to add or delete the BS to or from the paging group (eg, action code=0000). The paging group action response message may also be transmitted to provide its paging information (eg, action code=0001), or to query paging information from another base station (eg, action code=0010). An exemplary paging group action response message is shown in Table 12.

[Table 12]

field size Notes MessageType = 8 bits Sender ID 48 bits The identifier of the base station that sent this message Receiver ID 48 bits The identifier of the paging controller that received this message timestamp 32 bit action code 4 0000: Confirm assignment to paging group or remove from paging group 0001: Information (paging information of sender BS) 0010: Inquiry (paging information of another BS) 0100-1111: Reserved If(action code=0000){ reserve 4 will be set to zero } Else If(action code ＝0001){ Num Records 4 The number of paging group IDs associated with the sender BS For(i=0; j<Num Records; i++){ paging information 32 bit 0-7: Paging group ID, 8-23: Paging cycle, 24-31: Paging offset } } Else If(action code ＝0010){ Num BS 4 Among them, the number of BS that the paging message sender BS wants to know For(j=0; j<Num BS; j++){

Query BS ID 48 bits The identifier of the base station in which the paging information is included } } security field TBD means of verifying this message

FIG. 6 is a schematic diagram illustrating an idle mode activation process in a wireless access system with a paging controller according to an embodiment of the present invention.

Referring to FIG. 6, when the MSS intends to enter the idle mode, the MSS may transmit an idle mode entry request (eg, DREG-REQ) message to the BS to which the MSS belongs to request the idle mode entry (S61). The DREG-REQ message may include information related to requesting de-registration from the BS to which the MSS belongs (for example, a de-registration request code), and TLV-encoded information (for example, paging cycle request TLV, idle mode hold information TLV, MAC hash Skip Threshold TLV).

The serving BS may receive the idle mode entry request message, and transmit an idle mode information request (eg, Idle-Info_REQ) message to provide information on the MSS requesting the idle mode entry to the paging controller (S62). Table 13 shows an exemplary idle mode information request message.

[Table 13]

field size Notes Idle-Info-REQ message format () { global message header 12 bits For(i=0; i<Num Records; i++){ MSS MAC address 48 bits

action code 4 0000: idle mode start request 0001: DL business that has arrived at MSS 0010: MSS session information 0011: MSS re-entry completed 0100: MSS has transitioned to another paging group 0101-1111: reserved reserved 4 TLV encoded information Variable Num_SFID_Records 8 bits For(i=1; i<Num_SFID_Records; i++){ SFID 32 bit Num_QoS_Records 8 bits For(i=1; i<Num_QoS_Records; i++) TLV encoded information Variable 11.13 Service flow management coding } } } security field TBD means of verifying this message }

name type length value paging information 4 0-7: Paging group ID 8-23: Paging cycle 24-31: Paging offset Paging Controller ID 6 Logical network identifier of the serving BS or other network entity used to maintain MSS service and operation information, and/or manage MSS paging behavior in idle mode. Hold information in idle mode Variable The first 8 bits of this item represent the idle mode hold information included in the DREG-CMD message, and the remaining part is the MSS service and operation information related to the idle mode hold information. This item may be included in an Idle-Info-REQ message with Action Code = 0000. MAC hash jump crosses the threshold 1 When the action code for MSS is 00, "no action required", the maximum number of times the BS is allowed to skip the MSS MAC address hash of the MSS in successive MOB_PAG-ADV messages. The unit is the number of MOB_PAG-ADV message transmissions HO optimization flag 1 This item MAY be included in an Idle-Info-REQ message with Action Code = 0011.

With reference to Table 13, the idle mode information request message preferably can include information that a specific MSS has requested idle mode entry, MSS MAC address, MSS service flow information, and TLV encoded information (for example, idle mode keeps information TLV, MAC Hash Skip Threshold TLV).

The paging controller may receive the idle mode information request message, and transmit an idle mode information response (eg, Idle-Info-RSP) message to the BS transmitting the idle mode information request message (S63). If the idle mode information request message transmitted from the serving BS includes information relevant to the MAC hash skipping threshold, the paging controller preferably can transmit the idle mode information response message to all BSs belonging to the paging group ( S65).

Table 14 shows an exemplary idle mode information response (Idle-Info-RSP) message.

[Table 14]

field size Notes Idle-Info-RSP message format () { global message header 152 bits For(i=0; i<Num Records; i++){ MSS MAC address 48 bits action code 4 0000: MSS enters idle mode 0001: MSS exits idle mode 0010: MSS session information 0011: Send DL service to the current connected BS 0100-1111: Reserved reserve 4 TLV-encoded information Variable For(i=1; i<Num_SFID_Records; i++){ SFID 32 bit

Num_QoS_Records 8 bits For(i=1; i<Num_QoS_Records; i++) TLV-encoded information Variable 11.13 Service flow management coding } } } security field TBD means of verifying the message }

With reference to Table 14, the idle mode information response (Idle-info-RSP) message preferably can include information that the MSS has entered the idle mode, MSS MAC address, MSS service flow information, and TLV encoded information (for example, paging information TLV, Paging Controller ID TLV, Idle Mode Hold Information TLV, MAC Hash Skip Threshold TLV).

The BS may receive an idle mode information response (Idle-Info-RSP) message, and may transmit an idle mode command (eg, DREG-CMD) message to the MSS requesting the idle mode entry (S64). The idle mode command message preferably can include information related to command idle mode entry, and TLV encoded information (for example, paging information TLV, paging controller ID TLV, idle mode keeping information TLV, MAC hash skipping Threshold TLV).

FIG. 7 is a flowchart illustrating traffic occurrence in an idle mode mobile station in a wireless access system with a paging controller according to an embodiment of the present invention.

Referring to FIG. 7, the MSS may enter an idle mode (S71-S74). An MSS in idle mode may stay in a BS area where idle mode entry is performed, or may move into another BS area. An exemplary case in which an MSS in an idle mode moves to a second BS area will be described below.

If downlink traffic occurs in the idle mode, the first BS to which the MSS belongs when entering the idle mode may transmit information that the downlink traffic has occurred in the idle mode MSS to the paging controller (S75). The paging controller may transmit a paging announcement message to inform all BSs in each paging area that the idle mode MSS has terminated the idle mode to re-enter the network (S76, S77). The BS may then broadcast a paging announcement message (eg, MOB-PAG-ADV). An exemplary paging announcement message is shown in Table 6.

Table 15 shows an exemplary paging announcement message.

[Table 15]

field size note paging notification message format() Global message header 152 bits For(i=0; i<Num Records; i++){ MSS MAC address 48 bits action code 4 0000: MSS will be paged to re-enter the network 0001: MSS will be paged to perform ranging 0010-1111: Reserved reserved 4 } security field TBD means of verifying this message }

While in idle mode, in this example the MSS has moved into the area of the second BS. The MSS can recognize the presence of downlink traffic via a paging announcement message (eg, MOB_PAG-ADV) periodically broadcast to the paging zone. Then, the MSS may transmit a ranging request message for network re-entry to the second BS (S78). The second BS may request MSS session information related to the time before the idle mode entry from the paging controller using the idle mode information request message (S79). Preferably, the paging controller can transmit an idle mode information response message to the second BS (S80), the idle mode information response message including MSS session information and information about the BS where the MSS is located when entering the idle mode .

The second BS may transmit a ranging response message including a handover optimization flag to the MSS based on the MSS session information and idle mode maintenance information transmitted from the paging controller (S81). Once the MSS performs the network re-entry procedure (S82), the second BS in charge of the area where the MSS is currently located may inform the paging controller via an idle mode information request message that the MSS has re-entered the network (S83). In doing so, the second BS may include the handover optimization flag (which is included in the ranging response message) in the idle mode information request message.

Preferably, the paging controller can recognize that the MSS re-enters the network in the area of the current second BS after having completed idle mode entry in the first BS. The paging controller may then command (indicate) that the traffic transmitted to the first BS is transmitted to the MSS via the second BS using the idle mode information response message (S84).

The first BS can transmit the service to the second BS according to the command (instruction) of the paging controller. Then, the second BS can transmit the traffic to the MSS (S85). Then, the paging controller may notify all BSs belonging to the paging group that the MSS has terminated the idle mode using the idle mode information response message (S86). Each BS may receive an idle mode information response message from the paging controller and delete the MAC address of the MSS from its respective idle mode MSS list.

In one embodiment, if the downlink traffic transmitted to the MSS in idle mode is transmitted via the paging controller, steps S75 and/or S84 may be omitted.

In another embodiment, a method of supporting a mobile station in an idle mode in a wireless communication system using a paging controller includes entering the idle mode by the mobile station. The method also includes receiving a paging order from at least one of the plurality of base stations in the same paging group, the paging order including performing ranging while the mobile station is in idle mode to verify that the mobile station is paging command action codes associated with availability of at least one of the base stations in the group, wherein the paging command is generated from the at least one of the plurality of base stations in response to a paging announcement from a paging controller. The method also includes exiting the idle mode and establishing communication with one of the plurality of base stations, wherein the plurality of base stations in the same paging group receive the idle mode present status from the paging controller.

The paging announcement may preferably be generated from the paging controller when there is downlink traffic data to be transmitted to the mobile station. Alternatively, the paging announcement may preferably be generated from the paging controller when there is uplink traffic data from the mobile station. The idle mode response command may preferably include at least one of a paging identifier, a paging cycle and a paging cycle offset. Preferably, the step of exiting the idle mode and establishing communication may further comprise transmitting a ranging request to one of the plurality of base stations with which the mobile station is associated, and receiving a ranging response from the one of the plurality of base stations.

The paging announcement may preferably include a paging announcement action code that includes at least one of the following: (1) adding the mobile station to the paging list; (2) deleting the mobile station from the paging list ; (3) perform ranging to establish a position; and (4) enter the network. The paging command action code may preferably include at least one of (1) entering the network and (2) performing ranging to establish a location.

Preferably, the step of entering the idle mode may further comprise requesting, by the mobile station, a serving base station associated with a paging controller controlling a plurality of base stations associated with the paging group to enter the idle mode. Preferably, the step of entering the idle mode may further comprise receiving an idle mode response command from the serving base station to enter the idle mode.

The paging controller is preferably identifiable by means of a paging controller identifier, and the mobile station is identifiable by means of a media access controller (MAC) identifier. The paging command may preferably include information to identify the mobile station by using the MAC identifier. The paging announcement may preferably include information identifying the mobile station by using the MAC identifier. Preferably, the step of entering the idle mode by the mobile station may further comprise the paging controller notifying the plurality of base stations in the paging group of the idle mode entry status of the mobile station.

In yet another embodiment, a method for supporting idle mode by a network in a wireless communication system using a paging controller includes: receiving a request from a mobile station to a serving base station to enter the idle mode, wherein the serving base station is associated with the paging A paging controller controls a plurality of base stations associated with a paging group. The method also includes transmitting an idle mode response command from the serving base station to the mobile station to enter the idle mode. The method also includes transmitting a paging command from at least one of the plurality of base stations in the same paging group, the paging command including performing ranging while the mobile station is in idle mode to verify that the mobile station is A paging command action code related to the availability of at least one of the base stations in the group, wherein the paging command is generated from the at least one of the plurality of base stations in response to a paging announcement from a paging controller. The method also includes establishing communication between one of the plurality of base stations and the mobile station. The method also includes communicating the idle mode present status from the paging controller to the plurality of base stations in the same paging group.

Preferably, the method may further comprise transmitting an idle mode information request message from the serving base station to the paging controller to provide information related to the mobile station. Preferably, the method may further comprise receiving, in the paging controller, an idle mode information request message from the serving base station. Preferably, the method may further include transmitting an idle mode information response message from the paging controller to a plurality of base stations if the idle mode information request message includes information related to a medium access controller (MAC) hash skipping threshold at least one.

The method may also preferably comprise receiving, in the paging controller, an idle mode information request message from the serving base station, and transmitting an idle mode information response message from the paging controller to the serving base station. The idle mode information response message may also preferably be transmitted to at least one of the plurality of base stations, and may preferably include information informing at least one of the plurality of base stations that the mobile station has terminated the idle mode. The method may also preferably include transmitting an idle mode command message from the serving base station to the mobile station in response to the idle mode information response message.

Therefore, in the present invention, each base station can include the operation of the MSS in idle mode in the paging announcement backbone message. The paging announcement backbone message may be transmitted between base stations by wire via paging. Therefore, the present invention can reduce the size of the paging message (eg, MOB-PAG_ADV) transmitted by the MSS to the MSS in idle mode. In addition, in a wireless access system having a paging controller, the present invention can efficiently support idle mode using the paging controller.

It will be apparent to those skilled in the art that various modifications and changes can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents.

Industrial Applicability

The present invention can be applied to broadband wireless access systems.

Claims (12)

CLAIMS 1. A method of supporting a mobile station in idle mode in a wireless communication system using a paging controller, the method comprising: receiving an idle mode response command from the first base station to enter the idle mode; the mobile station enters idle mode; Receive a paging command from at least one of a plurality of base stations in the same paging group, the paging command includes a paging command action code, the paging command action code is related to the mobile station performing re-entry into the network, wherein the paging command is generated from at least one of the plurality of base stations in response to a paging announcement, wherein the paging announcement is generated by the paging controller to instruct the mobile station to perform network re-entry, wherein the paging announcement includes a paging announcement action code; end idle mode; When the mobile station moves into the area of a second base station in the paging group, and when the paging command action code indicates that the mobile station should enter the network, sending a ranging request message to the second base station to re-enter the network; receiving a ranging response message from the second base station; and Downlink traffic data is received from the second base station, wherein the downlink traffic data has been transferred from the first base station to the second base station according to instructions of the paging controller. 2. The method of claim 1, wherein the idle mode response command includes at least one of a paging identifier, a paging cycle, and a paging cycle offset. 3. The method according to claim 1, wherein the step of entering idle mode further comprises: A first base station is requested by a mobile station to enter an idle mode, wherein the first base station is associated with a paging controller that controls a plurality of base stations associated with a paging group. 4. The method of claim 1, wherein the paging controller is identified by a paging controller identifier, and the mobile station is identified by a media access controller (MAC) identifier. 5. The method of claim 4, wherein the paging command includes information identifying the mobile station by using the MAC identifier. 6. The method of claim 4, wherein the paging announcement includes information identifying the mobile station by using the MAC identifier. 7. The method of claim 1, wherein the step of entering the idle mode by the mobile station further comprises the paging controller notifying the plurality of base stations in the paging group of the idle mode entry status of the mobile station. 8. A method of supporting an idle mode through a network in a wireless communication system using a paging controller, the method comprising: receiving a request to enter idle mode from a mobile station by a first base station, wherein the first base station is associated with a paging controller that controls a plurality of base stations associated with a paging group; transmitting an idle mode response command from the first base station to the mobile station to enable the idle mode; transmitting a paging command from at least one of a plurality of base stations in the same paging group to the mobile station, the paging command including a paging command action code, the paging command action code is related to the mobile station performing re-entry into the network, wherein The paging command is generated from at least one of the plurality of base stations in response to a paging announcement from a paging controller that generates the paging when there is downlink traffic data to be transmitted to the mobile station notification to instruct the mobile station to perform network re-entry, wherein the paging notification includes a paging notification action code; When the mobile station moves into the area of a second base station in the paging group, and when the paging command action code indicates that the mobile station should enter the network, the second base station receives a ranging request message from the mobile station to re-enter the network; sending a ranging response message from the second base station to the mobile station; transferring downlink traffic data from the first base station to the second base station according to an instruction of the paging controller; and Downlink traffic data is transmitted from the second base station to the mobile station. 9. The method of claim 8, wherein the idle mode response command includes at least one of a paging identifier, a paging cycle, and a paging cycle offset. 10. The method according to claim 8, wherein after the step of the first base station receiving a request to enter the idle mode from the mobile station, further comprising: An idle mode information request message is transmitted from the first base station to the paging controller to provide information related to the mobile station. 11. The method according to claim 10, wherein, after the idle mode information request message is transmitted from the first base station to the paging controller, further comprising: the paging controller receives the idle mode information request message from the first base station; and An idle mode information response message is transmitted from the paging controller to at least one of the plurality of base stations if the idle mode information request message includes information related to a medium access controller (MAC) hash skipping threshold. 12. The method according to claim 10, wherein, after the idle mode information request message is transmitted from the first base station to the paging controller, further comprising: the paging controller receives the idle mode information request message from the first base station; and An idle mode information response message is transmitted from the paging controller to the first base station.

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