ES2394687T3 - Availability check of mobile subscriber stations in standby mode in a wireless access system - Google Patents

Abstract

A method for verifying the availability of a mobile subscriber station (210) that is in a standby mode, the method comprising: transmitting, to the base station (220) by the mobile subscriber station (210), a message of Request for registration (DREG-REQ) requesting to enter the standby mode, where the base station (220) is associated with a call group comprising a plurality of base stations, and each of the base stations in the call group maintains a list of standby mode; 10 receive, by the mobile subscriber station (210) from the base station (220), a deregistration command message (DREG-CMD) that allows to enter the standby mode, comprising the command message Deregistration (DREG-CMD) of at least one of a call identifier, a call cycle and a call cycle shift, and receive a subscriber warning message from the base station (220) from the base station (220). call that includes an action code n associated with the completion of an adhesion, where if the adhesion request is not received by the base station (220) for a predetermined period, the base station (220) continues to retransmit the call notification message until the account retries The call mode reaches a predetermined threshold, the standby mode list will be updated to delete the mobile subscriber station (210) in response to a message from the central network from the base station (220), and the message from the central network is associated with the unavailability of the subscriber's mobile station (210) in the call group.

Description

Checking availability of mobile subscriber stations in standby mode in a wireless access system 5

Technical field

The present invention relates generally to a wireless access system and, more particularly, to the verification of the availability of a mobile subscriber station in idle mode in a wireless access system.

Technical background

Wireless broadband access systems typically support a sleep mode to minimize the

15 power consumption of the mobile subscriber station (MSS). During idle mode, the MSS does not perform transfer procedures when moving between base stations in the same calling area. Therefore, the MSS does not need to transmit uplink information for a transfer procedure, which reduces the corresponding power consumption.

A call zone is defined as a zone that is controlled by a plurality of base stations called a call group. Each of the base stations in the call group has the same call cycle (Call_Cycle) and the same call offset (Call_Scroll).

The MSS can make a request to a base station to switch to standby mode. Base station

25 then provides a call notification message that includes its call group ID, a corresponding call cycle and a corresponding call offset. In this way, the corresponding MSS can be switched to the idle state. During idle mode, the MSS can determine whether to continue or terminate the idle mode based on the call notification message provided by the base station in each of the call cycles.

If traffic is required to be transmitted through the MSS while in idle mode, the MSS may terminate the idle mode. For example, the MSS can be enabled to terminate the sleep mode by the BS. In addition, if the MSS moves to another call zone or loses its synchronism while it is in standby mode and is unable to receive a call at a predefined time, the MSS may terminate the standby mode.

35 When the MSS is in standby mode, the MSS normally receives a periodic call to ensure its free movement in the same calling area without performing the transfer procedure provided there is no reception or transmission traffic.

A procedure of an MSS entering sleep mode is explained in detail as follows. The MSS supplies a standby mode request message to the BS in service to enter the standby mode. The BS in service provides a call group ID, a call cycle, a call movement to the MSS through an idle response message. The BS in service also releases the connection information to the MSS, as well as the radio resources allocated to the MSS. In addition, the BS in service provides an address

MAC of the MSS entering the standby mode to the BS of its call group so that each of the BSs can call the corresponding MSS for the same call cycle.

The MSS is allowed to enter the standby mode through the standby mode response message after determining if there is downlink traffic that needs to be supplied to the MSS by evaluating a call alert message of a broadcast format supplied from the BS according to the call cycle. Determinations are also made as to whether to perform an adhesion or to maintain the sleep mode.

FIG. 1 is a diagram showing a format of a call notification message received by a mobile subscriber station (MSS) in the standby mode from a base station (BS).

Referring to FIG. 1, if the call alert message establishes that there is downlink traffic for the MSS, the MSS terminates the idle mode and registers again in the network to receive the downlink traffic. If the MSS is requested to make an adhesion through the call notification message, the MSS makes the adhesion to allow the BS to update a location of the MSS and a list of the MSS in idle mode. If the call alert message instructs the MSS not to take any action, the MSS remains in standby mode.

After this, if uplink or downlink traffic needs to be communicated or if the group of

The call is transferred to another BS to terminate the MSS standby mode, the BS informs the other BSs that belong to the same call group so that the other BSs can remove the corresponding MSS from the list

of MSS in sleep mode.

When the MSS is in idle mode, the MSS normally does not have uplink traffic. Thus, to provide continuous availability of the MSS, the BS supplies the call warning message to the MSS to enable the corresponding MSS to adhere. The BS can verify the availability of the MSS after receiving the uplink information by means of a request for membership from the MSS.

However, when the MSS is turned off, or when the MSS is in a poor channel environment, the MSS may fail to receive the call alert message even if the BS establishes the call warning message (for example, an action code is set '0x01 (make adhesion)' or '0x02 (enter network)') for its supply. Also, in this case, the BS may not receive the adhesion request message from the MSS. Thus, if the MSS is unable to function normally, the BS can determine that the MSS is no longer available. In addition, the BS may need to release all management resources (for example, the MAC address for the call, etc.) for the corresponding MSS and have to remove the other BSs from the same call group the corresponding MSS

15 of your MSS lists at rest.

Document US 6 178 164 B1 discloses that, in a mobile communications system having a first communications device for communicating with a plurality of second communications devices, a method for making a transfer within the mobile communications system includes transmission from at least one of the second communication devices to the first communication device a list of transfers of the second communication devices to which the first communication device is allowed to transfer. A channel assignment message is transmitted from each of the second communication devices in the transfer list. The transfer list includes the base stations, controlled by a single controller that determines which of the second communication devices it transmits

25 the channel assignment message.

Disclosure of the invention

Accordingly, the present invention is directed to verify the availability of a mobile subscriber station in a wireless access system that substantially avoids one or more problems of the related art.

An object of the present invention is to provide a method for updating a list of mobile subscriber stations (MSS) in standby mode available by a base station (BS) using a call alert message supplied to the MSS.

Additional advantages, objects and features of the invention will be shown in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or what can be learned from the implementation of the invention. . The objects and other advantages of the invention can be realized and achieved by the structure particularly pointed out in the written description and the claims thereof as well as the accompanying drawings.

The objects of the present invention are achieved by the subjects object of the independent claims.

To achieve these objects and other advantages and in accordance with the purpose of the invention, how it will be carried out and

45 will describe extensively in this document, in one embodiment, a method for checking the availability of a mobile subscriber station that is in the standby mode includes requesting the base station by the mobile subscriber station to enter the standby mode. , wherein the base station is associated with a call group comprising a plurality of base stations, and receiving from the base station a standby mode response command to enter the standby mode, the mode response command comprising At least one of the idlers, a caller ID, a call cycle and a call cycle shift. The method also includes receiving from the base station a call command comprising an action code associated with performing an adhesion while the mobile subscriber station is in idle mode to verify the availability of the mobile subscriber station with with respect to the base station, where if the adhesion is not performed satisfactorily with the base station for a predetermined period, the base station

55 continues to transmit the call command until the call retry count reaches a predetermined threshold.

The call command can preferably be received when there is no downlink data. When the call retry count reaches the predetermined threshold, then the mobile subscriber station can preferably be removed from the idle mode list maintained by the base station. The elimination of the mobile subscriber station from the standby mode list can preferably be performed on each of the plurality of base stations in the call group.

The predetermined period may preferably be the call cycle. As an alternative, the period

65 may be based on the expiration of the time associated with the maximum time allocated for the mobile subscriber station to send an adhesion request in response to a call command from the station

base.

When the call retry count reaches the predetermined threshold, then the mobile subscriber station can preferably be removed from a standby mode list maintained by a call controller. The call command can preferably be received when there is traffic data to be transmitted on the downlink to the mobile subscriber station.

In another embodiment, a method of verifying the availability of a mobile subscriber station that is in the standby mode includes the request to a call controller by the mobile subscriber station to enter the standby mode, wherein the controller The call is associated with a call group comprising a plurality of base stations, and receiving from the call controller a standby mode response command to enter the standby mode, the standby mode response command comprising the minus one of, a caller ID, a call cycle and a call cycle shift. The method also includes receiving from the call controller a call command comprising an action code

15 associated with the realization of an adhesion while the mobile subscriber station is in idle mode to verify the availability of the mobile subscriber station with respect to the call controller, where if the adhesion is not successful with the controller During a predetermined period, the call controller continues to transmit the call command until the call retry count reaches a predetermined threshold.

In yet another embodiment, a method of checking the availability of a mobile subscriber station that is in the standby mode includes receiving from the mobile subscriber station a request to enter the standby mode, where a base station is associated with a call group operatively connected to a plurality of base stations, and transmit a response command of the mode of subscriber to the mobile subscriber station

25 standby to enter standby mode in response to the request to enter standby mode, the standby mode response command comprising at least one of, a caller ID, a call cycle and a cycle shift call. The method also includes transmitting to the mobile subscriber station a call command comprising an action code associated with the performance of adhesion while the mobile subscriber station is in idle mode to verify the availability of the mobile subscriber station. with respect to the base station, where if the adhesion is not successful with the base station for a predetermined period, the base station continues to transmit the call command until the call retry count reaches a predetermined threshold.

It will be understood that both the above general description and the following detailed description of this

The invention is exemplary and explanatory and is intended to provide a further explanation of the invention as claimed.

The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. It will be understood that both the above general description and the following detailed description of the present invention are exemplary and explanation and attempt to provide a further explanation of the invention as claimed.

Brief description of the drawings

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

FIG. 1 is a diagram showing a format of a call notification message received by a mobile subscriber station (MSS) in the standby mode from a base station (BS).

FIG. 2 is a diagram showing the verification of the availability of an MSS based on a call cycle in a wireless access system, in accordance with an embodiment of the present invention.

55 FIG. 3 is a diagram showing the verification of the availability of an MSS using a timer in a wireless access system according to an embodiment of the present invention.

FIG. 4 illustrates a signaling operation of the MSS in the sleep mode, in accordance with an embodiment of the present invention.

Best embodiment of the invention

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which

65 are illustrated in the accompanying drawings. Whenever possible, the same numerical references will be used throughout the drawings to refer to the same or similar parts.

In one embodiment, the present invention is implemented in a wireless broadband access system. In another embodiment, the present invention is implemented in a wireless communications system that operates in accordance with a non-broadband standard.

5 In yet another embodiment, when a mobile subscriber station (MSS) is in the idle mode, it checks the completion of an adhesion command from a base station in service (BS in service) in each call cycle. In other words, the BS in service periodically sends an adhesion completion command to the MSS to check if the MSS is "alive". If the execution of an adhesion command is present, then the MSS can send an adhesion request to the BS in service. If the BS in service does not receive an adhesion request from the MSS, then the BS in service can repeatedly send an adhesion command until a call retry threshold is met. Once the call retry threshold is met, the BS in service removes the MSS from the MSS list in idle mode.

In yet another embodiment, an MSS enters the idle mode and the BS in service is enabled to verify the

15 availability of the MSS using various parameters, including a Call Retry Account, and a Timeout for Receiving Uplink Information (Waiting Time for Receipt of the Request for Adhesion Message). A mobile subscriber station is referred to as an MSS, regardless of whether or not it is in the idle state.

The availability of the MSS can be verified using the Call Retries Account, and the Reception Timeout of the Uplink Information. Alternatively, the availability of the MSS can be verified using only the Call Retry Account. Alternatively, the availability of the MSS can be verified using only the Reception Timeout of the Uplink Information. The Reception Timeout of the Uplink Information can preferably be set equal to a cycle of

25 call Alternatively, the Timeout for Receiving Uplink Information can preferably be determined by a timer.

The MSS may lose synchronization of the call messages supplied periodically from the BS in service causing the MSS to fail to receive the call messages from the BS in service. If the MSS fails to receive call messages from the BS in service, the MSS can perform a new network registration procedure. On the other hand, if the BS in service fails to receive the uplink information from the MSS, despite requiring the MSS to send the uplink information through the call warning message, the BS in service preferably decide that the MSS is not available.

35 The call notification message is set to provide a request for accession to the BS in service from the MSS. The MSS can supply the request for adhesion to the BS in service through an uplink adhesion channel based on competition. If the BS in service requests an adhesion execution from the MSS, but fails to receive the adhesion request message from the MSS for a specified duration of a Waiting Time for the Adhesion Request Message, the BS in service I could preferably determine that adhesion has failed.

FIG. 2 is a diagram showing the verification of the availability of an MSS based on a call cycle in a wireless access system, in accordance with an embodiment of the present invention.

45 With reference to FIG. 2, MSS 210 enters standby mode by supplying a registration release request (DREG-REQ) to the BS in service 220. The BS in service 220 responds to the DREG-REQ message by supplying a call group ID (PG -ID), a call cycle (PG-CYC), and a call shift (PG-OFFSET) to the MSS 210. The BS in service 220 can also release the connection information to the MSS 210, and the resources of radio assigned to MSS 210.

The BS in service 220 then provides a MAC address of the MSS 210 which enters the standby mode to the BSs of the call group of the BS in service 220 to enable each of the BSs to send call messages to the MSS 210 for the same call cycle. For example, each of the BSs may preferably transmit a call warning message (MOB-PAG-ADV) to instruct the MSS 210 to request a

55 adhesion.

The MSS 210 can be allowed to enter standby mode through a register release command (DREG-PAG-ADV), and it can determine whether downlink traffic has been provided to the MSS 210 through the message of Formatted broadcast call notification supplied from the BS in service 220 according to the call cycle. The MSS 210 can also determine whether to execute the adhesion and / or maintain the sleep mode. In the verification of the availability of the MSS in FIG. 2, the call cycle and call retry account can be used.

After the transmission of the call notification message (MOB-PAG-ADV) Action Code = accession

65 or network entry) to MSS 210, the BS in service 220 is stopped during a call cycle until an adhesion request message is received from the MSS 210. If the BS in service 220 does not receive link information ascending from MSS 210 before the time for the supply of the following call warning message, for example, after the expiration of the call cycle, the BS in service 220 may preferably determine that adhesion (adhesion failure) has failed. In such a case, the availability of the MSS 210 can be verified using the Reception Timeout of the Uplink Information. The BS in service 220 can determine

5 that MSS 210 is not available and remove MSS 210 from the list of MSS in idle status. Alternatively, a call controller that is connected to a plurality of BS can determine that MSS 210 is unavailable and remove MSS 210 from the MSS list in idle mode.

The call retries account indicates an account of retries made by the BS in service 220 that fail

10 upon receipt of the membership request from MSS 210. The BS in service 220 can supply the call notification message ((MOB-PAG-ADV) (Action Code = make accession or network entry)) including a predefined call retry account to the MSS 210. If the BS in service 220 fails to receive the membership request from the MSS 210 despite the provision of the call warning message, the BS in service 220 may preferably determine that MSS 210 is not available and remove MSS 210 from the MSS list

15 in sleep mode. In this way, the availability of the MSS 210 can be verified using two parameters, the call cycle and the call retry count.

If the BS in service 220 receives the adhesion request from the MSS 210, the BS in service 220 (or the call controller) can update the availability of the MSS 210 through the MSS list in idle mode and

20 notify BSs belonging to the same call group to enable BSs belonging to the same call group to update their standby mode lists through a message from the central network.

On the other hand, if the BS in service 220 fails to receive the adhesion request from the MSS 210 within a predetermined time through a call cycle establishment and the call retry, the BS in

The service can preferably remove the MSS 210 from the list of available MSS in idle mode and release the management resources and information associated with the MSS 210. The BS in service 220 may also preferably use a message from the central network to Notify BSs belonging to the same call group to remove MSS 210 from their MSS lists in idle mode.

30 FIG. 3 is a diagram showing the verification of availability of an MSS using a timer in a wireless access system, in accordance with an embodiment of the present invention.

Referring to FIG. 3, the availability of the MSS 210 can be verified using a timer and a call retry account.

35 After the transmission of the call notification message (MOB-PAG-ADV) (Action Code = accession

or network entry), the BS in service 220 can be stopped during the timer's operational time until an adhesion request message is received from the MSS 210. If the BS in service 220 does not receive the uplink information from MSS 210 before the time for the supply of the following call notification message

40 (based on the expiration of the timer), the BS in service 220 may preferably determine that adhesion has failed. When the verification of the availability of the MSS 210 is only by waiting for the uplink reception, the BS in service 220 may preferably determine that the MSS 210 is not available and remove the MSS 210 from the MSS list in Sleep mode

45 The BS in service 220 can supply the call warning messages (MOB-PAG-ADV) (Action Code = make accession or network entry) including a predefined call retry account to the MSS 210. If the BS in service 220 fails to receive the membership request from MSS 210 despite the provision of call messages, the BS may decide that MSS 210 is not available and remove MSS 210 from the MSS list in mode of rest.

50 The availability of the MSS 210 can be checked using two parameters, the call cycle and the call retry count. The availability of the MSS 210 can be determined according to an establishment of each of the parameters.

In one embodiment, if a timer operating cycle is lower than the call cycle, the BS in service 220 may determine the availability of the MSS 210 through the call retries account. In an update of the availability of the MSS 210 through the call retries account, the use of the timer may be unnecessary. For example, if the BS in service 220 fails to receive the uplink information from the MSS 210 before the next call time begins (after

60 supply of the call warning message (MOB-PAG-ADV)), the BS in service 220 can determine that an adhesion failure has occurred and perform a call retry. In another embodiment, when the call retry count is set to zero, if the timer expires after the call warning message is provided to cause the MSS 210 to request initial adhesion, the BS in service 220 may determine that The MSS 210 is not available.

65 In yet another embodiment, a request for membership of the MSS 210 is made through a competition-based call channel. That is, the call command may not be based on the call cycle. Instead, the retry to make the adhesion is based on the expiration of the timer. The expiration of the timer can be based on the maximum time allocated to MSS 210 for sending the membership request. In this embodiment, it

5 you can use a procedure similar to that of an initial adhesion. The MSS 210 may preferably remain for a maximum of 200 ms waiting for an adhesion response message after the supply of the adhesion request message to the in service BS 220. After receipt of the adhesion response message from the in service BS 220, the MSS 210 may remain for a maximum of two seconds to deliver the following adhesion request message. The waiting time of a maximum of two seconds can be applied to the retransmission of the following adhesion request message due to the failure to receive the adhesion response message. In yet another embodiment, the MSS 210 membership request retry count is at least sixteen. Thus, using the two waiting times and the retry of the request for membership, the waiting time for the request for membership from the BS in service 220 can be determined according to the timer. In yet another embodiment, the corresponding wait time is at least thirty-three seconds.

In yet another embodiment, when the BS in service 220 has previously assigned an uplink channel for accession for the MSS 210, by means of the call warning message (MOB-PAG-ADV), it is unnecessary for the BSs that belong to the call group assign the uplink call channel for MSS 210 for an extended duration. Thus, in this embodiment, the verification of the availability of the MSS 210 through the timer may be mandatory. In the case of mandatory availability verification, the timer can be set by a frame unit. If there is no accession request from the MSS 210 within the fixed frame unit, the BS in service 220 can release the uplink channel assigned to the MSS 210 and remove the MSS 210 from the MSS list in the mode of repose.

25 In one embodiment, if the BS in service 220 receives the adhesion request from MSS 210, the BS in service 220 can update the availability of MSS 210 through the MSS list in idle mode and send a message from the central network to enable other BSs belonging to the same call group to update their MSS lists in idle mode.

In another embodiment, if the BS in service 220 fails to receive the adhesion request from the MSS 210 within the predefined time through the timer and the establishment of call retry, the BS in service 220 can eliminate the MSS 210 from the MSS list of idle mode and release the management and information resources associated with the MSS 210. The BS in service 220 can also use the central network message to notify the BSs belonging to the same call group as remove MSS 210 from your MSS lists in the mode of

35 rest.

In one embodiment, a method of checking the availability of a mobile subscriber station that is in the idle state includes requesting the base station by the mobile subscriber station to enter the standby mode, where the base station is associated with a call group comprising a plurality of base stations and the reception from the base station of a standby mode response command to enter the standby mode, the standby mode response command comprising at least one of, a caller ID, a call cycle and a call cycle shift. The method also includes receiving from the base station a call command comprising an action code associated with the performance of an adhesion while the mobile subscriber station is in the idle mode to verify the availability of the

45 mobile subscriber station with respect to the base station, where if the adhesion is not successful with the base station for a predetermined period, the base station continues to transmit the call command until the call retry count reaches a threshold predetermined.

The call command can preferably be received when there is no downlink data. When the call retry count reaches the predetermined threshold, then the mobile subscriber station can preferably be removed from the standby mode list maintained by the base station. The elimination of the mobile subscriber station from the standby mode list can preferably be performed on each of the plurality of base stations in the call group.

55 The predetermined period may preferably be the call cycle. Alternatively, the predetermined period may be based on the expiration of the time associated with a maximum time allotted for the mobile subscriber station to send an adhesion request in response to the call command from the base station.

When the call retry count reaches the predetermined threshold, then the mobile subscriber station can preferably be removed from the idle mode list maintained by a call controller. The call command can preferably be received when there is traffic data to be transmitted on the downlink to the mobile subscriber station.

65 In another embodiment, a method for verifying the availability of a mobile subscriber station that is in the idle mode includes requesting a call controller by the mobile subscriber station to enter the idle mode, where the controller of The call is associated with a call group comprising a plurality of base stations, and the reception from the call controller of a standby mode response command to enter the standby mode, the standby mode answer command comprising at least one of, a caller ID, a call cycle and a call cycle shift. The method

5 also includes the reception from the call controller of a call command comprising an action code associated with the performance of the adhesion while the mobile subscriber station is in the idle mode to verify the availability of the mobile station of subscriber with respect to the call controller, where if the adhesion is not successful with the call controller for a predetermined period the call controller continues to transmit the call command until a call retry account reaches a predetermined threshold.

In yet another embodiment, a method of checking the availability of a mobile subscriber station that is in the standby mode includes receiving from the mobile subscriber station a request to enter the standby mode, where the base station is associated with a call group operatively connected to

15 a plurality of base stations, and the transmission to the mobile subscriber station of a standby mode response command to enter the standby mode in response to the request to enter the standby mode, the response command comprising from standby mode at least one of, a caller ID, a call cycle and a call cycle shift. The method also includes the transmission to the mobile subscriber station of a call command comprising an action code associated with the performance of the adhesion while the mobile subscriber station is in the idle mode to verify the availability of the station mobile subscriber with respect to the base station, where if the adhesion is not successful with the base station for a predetermined period, the base station continues to transmit the call command until the call retry count reaches a predetermined threshold.

Accordingly, the present invention enables a BS in service to check the availability of an MSS. By checking the availability of the MSS, the BS in service prevents the MSS from failing to receive periodic call messages, such as in cases where the power of the MSS has been cut off or the channel status has degraded.

The BS in service can supply the update information of the availability belonging to the MSS to other BSs belonging to the same call group through the message of the central network, thus preventing the BSs belonging to the same call group provide the call notification message to an unavailable MSS.

In addition, when the uplink adhesion channel is reserved or allocated to the MSS, the BS in service can release the uplink channel assigned to the MSS and the management resources associated with the MSS. In this way, the power consumption of the MSS can be minimized and the MSS list in standby mode can be updated effectively.

In another embodiment of the present invention the MSS may choose to lower the power (or cut off the power) during sleep mode. By notifying the base station of its decision to lower the power, the corresponding information belonging to the MSS retained by the network (the last base station that granted the MSS the entry into standby mode or the call controller) can be deleted .

In the realization of the present application, an adhesion request message and an adhesion response message are used to comply with the power cut by the MSS. In operation, if the MSS tries to lower the power while in standby mode, a request to lower the power is transmitted by means of the network membership request message (the last base station, which granted the MSS to enter standby mode, or call controller). Subsequently, the network that receives the request to lower the power through the adhesion request message transmits various information to the MSS through the adhesion response message.

Figure 4 illustrates a signaling operation of the MSS in the sleep mode according to an embodiment of the present invention. Referring to Figure 4, the MSS transmits a request message to a first network entity asking to enter the standby mode through a deregistration request message (DREG

55 REQ) (S10). The first network entity may be a base station or a call controller. Included in the request message is a preferred session information from the MSS that the MSS prefers for the first network entity to maintain for a future accelerated re-entry into the network. This MSS preferred session information includes information such as verification information, Internet protocol (IP) address information, MSS capability, management connection identification, and essential information to maintain The network service.

After receiving the request message, the first network entity broadcasts through a central network channels a notification to at least one or all other network entities that have the same call identifications in the call group so that the corresponding MSS can be added to each of the entities

65 group call network (S20).

In response to the request message, the first network entity transmits a selected session information to the corresponding MSS by means of a deregistration response command (DREG-CMD) (S30). The selected session information includes certain MSS services and operational information useful for expediting a future re-entry of the MSS into the network from the idle state. The selected session information can be the

The same, different or a combination thereof as the preferred session information requested by the MSS. In addition, in the transmission of the DREQ-CMD, other information such as the call cycle, the call offset and the caller ID can be included. The DREG-CMD is a command or a message that grants the MSS the entry into sleep mode as requested.

10 Once the DREG-CMD is received from a second network entity, the MSS enters standby mode. During sleep mode, the MSS can receive a call alert message in the slots or time intervals specified from the first network entity (S40). The call notification message includes various information such as if there is any downlink traffic or when to end the idle mode.

15 If the MSS moves to the second network entity within the same call group that has the same call identification (S50), the MSS can receive call messages from the second network entity in the same call and shift cycle of call as received from the first network entity.

During this period (sleep mode), the MSS may experience a power reduction or simply

20 choose to lower the power. The corresponding MSS transmits to the second network entity a message indicating the power cut / drop (for example, a power down indicator) through an adhesion request message (S70). The second network entity then notifies the first network entity that the MSS has lowered the power and requests the first network entity to unregister or delete the MSS information from the MSS list in idle mode ( S80). In addition, the second network entity may transmit to the network entity that retains the

25 information about the MSS through a message indicating the status of the MSS standby mode, for example.

At the same time, the MSS may attempt to complete a location update once as part of its orderly procedure to lower the power. This mechanism enables the second network entity to update the exact state of the MSS and erase all the information for the MSS. In addition, this mechanism enables the second

30 network entity discontinue call control in idle mode for the MSS at the time of power down.

After the second network entity notifies the corresponding MSS that the location update of lowering power has been executed successfully, the second network entity may release all retention information from the MSS related sleep mode (S90 ). It is possible for the second network entity to fail to update the power down information. In such a case, the second network entity (for example, the call controller) can perform an availability check using the location update poll. The unavailability of the MSS can be determined and the second network entity will erase all hold information from the idle mode if the MSS does not respond to the location update poll of the

40 second network entity for the 'call retries account'.

The application of the embodiment of the present invention is not limited to requesting to lower the power in a coverage area of a different base station. Rather, it is possible to lower the power at the base station that granted the sleep mode without even leaving its coverage area or returning to its coverage area. The notification of downloading the

45 power by the MSS provides effective and efficient resource management in the area of BS coverage. Instead of the BS determining the status of the MSS, notifying the BS of the MSS of its attempt to lower the power, the BS can efficiently manage the MSS and the resources associated with the BS.

It will be apparent to those skilled in the art that various modifications and variations can be made in the

The present invention without departing from the scope of the inventions. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they fall within the scope of the appended claims and their equivalents.

Claims (15)

1. A method for checking the availability of a mobile subscriber station (210) that is in a standby mode, the method comprising: 5 transmit, to the base station (220) by the mobile subscriber station (210), a deregistration request message (DREG-REQ) requesting to enter the sleep mode, where the base station (220) is associated with a call group comprising a plurality of base stations, and each of the base stations in the call group maintains a list of the idle mode; receiving, by the mobile subscriber station (210) from the base station (220), a deregistration command message (DREG-CMD) allowing to enter the idle mode, comprising the deregistration command message (DREG-CMD ) at least one of a call identifier, a call cycle and a call cycle shift, and receive a call alert message via the mobile subscriber station (210) from the base station (220) 15 comprising an action code associated with the performance of an adhesion, wherein if the adhesion request is not received by the base station (220) for a predetermined period, the base station (220) continues to retransmit the warning message of called until the call retry count reaches a predetermined threshold, the standby mode list will be updated to remove the mobile subscriber station (210) in response to a message from the central network from the base station (220), and the central network message being associated with the unavailability of the mobile subscriber station (210) in the call group. 2. The method of claim 1, wherein the predetermined period is the call cycle. 25

3.

 The method of claim 1, wherein the predetermined period is based on the expiration of a time associated with a maximum time allocated for the mobile subscriber station (210) to send the adhesion request in response to the call warning message. from the base station (220).

Four.

 The method of claim 1, wherein the call warning message is received when there is traffic data to be transmitted over the downlink to the mobile subscriber station (210).

5.

 A method of checking the availability of a mobile subscriber station (210) which is in the idle mode, the method comprising:

35 requesting a call controller by the mobile subscriber station (210) to enter idle mode, wherein the call controller is associated with a call group comprising a plurality of base stations, and in which each of the base stations in the call group maintains a list of idle mode; receiving from the call controller an answer command in the idle mode to enter the idle mode, the answer command of the idle mode comprising at least one of a call identifier, a call cycle and a movement of the call cycle; and receive from the call controller a call command comprising an action code associated with the completion of adhesion, 45 where, if an adhesion request is not received by the call controller for a predetermined period, the call controller continues to transmit the call command until the call retry count reaches a predetermined threshold, the mode list of idle will be updated to eliminate the mobile subscriber station (210) in response to a message from the central network from the base station (220), and the message from the central network being associated with the unavailability of the mobile subscriber station (210) ) in the call group. 6. A method of checking the availability of a mobile subscriber station (210) which is in the idle mode, the method comprising: 55 receiving, by a base station (220) from the mobile subscriber station (210) a deregistration request message (DREG-REQ) requesting to enter the idle mode, where the base station (220) is associated with a call group operatively connected to a plurality of base stations, and in which each of the base stations in the call group maintains a list of idle mode; transmit by the base station (220) to the mobile subscriber station (210), a deregistration command message (DREG-CMD) which allows entering the idle mode in response to the deregistration request message (DREG-REQ) , the deregistration command message (DREG-CMD) comprising at least one of a call identifier, a call cycle and a call cycle offset; transmitting a call alert message via the base station (220) to the mobile subscriber station (210) 65 comprises an action code associated with the completion of the adhesion, retransmitting the call warning message to the mobile subscriber station (210) if an adhesion request message is not received by the base station (220) for a period default, where the base station (220) continues to retransmit the call alert message until the call retry count reaches a predetermined threshold; determine that the mobile subscriber station (210) is not available when the retries account of 5 call reaches the default threshold; and transmit a message from the central network to indicate that the standby mode list will be updated to remove the mobile subscriber station (210).

7.

 The method of claim 6, wherein the predetermined period is the call cycle.

8.

The method of claim 6, wherein the predetermined period is based on the expiration of a time associated with the maximum time allocated for the mobile subscriber station (210) to send the adhesion request in response to the call warning message. from the base station (220).

The method of claim 6, wherein the call warning message is received when there is traffic data to be transmitted on the downlink to the mobile subscriber station (210). 10. A mobile subscriber station (210) for reporting availability while in standby mode to a base station (220), the mobile subscriber station (210) comprising: means for transmitting, to the base station (220), a deregistration request message (DREG-REQ) requesting to enter the idle mode, where the base station (220) is associated with a call group comprising a plurality of base stations and each of the base stations in the call group maintains a list of the call mode; 25 means for receiving from the base station (220) a deregistration command message (DREG-CMD) which allows to enter the sleep mode, the deregistration command message (DREG-CMD) comprising at least one of, an identifier of call, a call cycle and a call cycle shift; and means for receiving from the base station (220) a call warning message comprising an action code associated with the completion of the adhesion, where if the adhesion request message is not received by the base station (220) for a predetermined period, the base station (220) continues to transmit the call alert message until the call retry count reaches a predetermined threshold and the standby mode list is updated to remove the mobile subscriber station in response to a message from the central network from the base station (220), the message from the central network being associated with the unavailability of the mobile subscriber station (210) in the call group.

eleven.

 The mobile subscriber station (210) of claim 10, wherein the predetermined period is the call cycle.

12.

 The mobile subscriber station (210) of claim 10, wherein the predetermined period is based on the expiration of a time associated with a maximum time allocated for the mobile subscriber station (210) to send the adhesion request message in response to the call warning message from the base station (220).

13. The mobile subscriber station (210) of claim 10, wherein the call alert message is received when there is traffic data to be transmitted on the downlink to the mobile subscriber station (210). 14. A base station (220) for checking the availability of a mobile subscriber station (210) which is in the idle mode, the base station (220) comprising: means for receiving a deregistration request message (DREG-REQ) to enter the standby mode from the mobile subscriber station (210), where the base station (220) is associated with a call group operatively connected to a plurality of base stations, and in which each of the base stations in the call group maintains a list of idle mode; means for transmitting to the mobile subscriber station (210) a deregistration command message (DREG 55 CMD) which allows to enter the idle mode in response to the deregistration request message (DREG-REQ), the deregistration command message (DREG-CMD) comprising at least one of, a caller ID, a cycle of call and a call cycle shift; means for transmitting to the mobile subscriber station (210) a call warning message comprising an action code associated with the completion of the adhesion; and means for retransmitting the call notification message to the mobile subscriber station if an adhesion request message is not received by the base station (220) until a predetermined period, where the base station (220) continues to retransmit the message call alert until the call retry count reaches a predetermined threshold, at which the base station (220) determines that the mobile subscriber station (210) is not available in the 65 call group when the call retry account reaches the predetermined threshold and transmits a message from the central network to indicate that the standby mode list will be updated to remove the mobile subscriber station (210). 15. The base station (220) of claim 14, wherein the predetermined period is the call cycle. The base station (220) of claim 14, wherein the predetermined period is based on the expiration of the time associated with the maximum time allocated for the mobile subscriber station (210) to send the adhesion request message in response to the call warning message from the base station (220). 17. The base station (220) of claim 14, wherein the call alert message is received when there is 10 traffic data to be transmitted on the downlink to the mobile subscriber station (210). FIG. one

Countryside

Size Notes

MOB-PAG-ADV_ Format_Message () {

Type of management message

8 bits

Group_NameCall ID

8bits Call Group ID number in this message

For (i = 0; i ≤ Call_Group_Number ID; I) {

Call Group ID

8 bits

}

For (j = 0; j <Num_MAC; j ++) {

Number of the MAC Addresses of the MSS in the message can be determined from the length of the message (found in the generic MAC header).

Fingerprint MAC address MSS

24 bit The fingerprint is obtained by calculating a CRC24 on the 48-bit MAC address of the MSS. The polynomial for the calculation is 0x864CFB.

Action Code

2 bits Call action instruction for MSS 00 = No action is required 01 = Perform membership to establish the location and confirmation message 10 = Enter the network 11 = Reserved

Reserved

6 bits

}

}