KR20070056860A - Method and system for operating sleep mode in a broadband wireless access communication system - Google Patents

Abstract

A sleep mode operation method in a BWA(Broadband Wireless Access) communication system and a system therefor are provided to enable each MS(Mobile Station) to exactly recognize whether each traffic indication message sent from a BS(Base Station) is for themselves, thereby accurately performing sleep mode operation of the system. A BS confirms whether an MS where a listening interval comes exists(301). If so, the BS confirms whether data to be transmitted to the MS where a sleep interval is terminated exists(303). If so, the BS increases the number of positive indications(305). If the data to be transmitted does not exist, the BS increases the number of negative indications(307). The BS updates the sleep interval by sleep interval update algorithm(309).

Description

Sleep mode operation method and system in a broadband wireless access communication system {METHOD AND SYSTEM FOR OPERATING SLEEP MODE IN A BROADBAND WIRELESS ACCESS COMMUNICATION SYSTEM}

1 is a diagram schematically illustrating a sleep mode operation of a general IEEE 802.16e communication system.

2 is a diagram schematically illustrating a sleep mode operation of a system including two MSs in a general IEEE 802.16e communication system.

3 is a diagram illustrating an operation process of a BS in a BWA communication system according to an embodiment of the present invention.

4 is a diagram illustrating an operation of an MS in a BWA communication system according to an embodiment of the present invention.

5 is a diagram schematically illustrating a sleep mode operation in a BWA communication system according to an embodiment of the present invention.

The present invention relates to a broadband wireless access communication system, and more particularly, to a sleep mode operation method and system of a communication system in which a sleep mode exists.

In the 4th Generation (hereinafter, referred to as '4G') communication system, a service having various Quality of Service (QoS) (QoS), which has a high transmission speed, is a next generation communication system. Active research is being conducted to provide users with the music. In particular, in the current 4G communication system, a wireless local area network (LAN) system and a wireless metropolitan area network (MAN) system are called. Researches are being actively conducted to support high-speed services in a form of guaranteeing mobility and QoS in a broadband wireless access (BWA) communication system. Representative communication systems are the Institute of Electrical and Electronics Engineers (IEEE) 802.16a communication system and the IEEE 802.16e communication system.

The IEEE 802.16a communication system and the IEEE 802.16e communication system are communication systems applying the OFDM / OFDMA scheme to support a broadband transmission network in a physical channel of the wireless MAN system. The IEEE 802.16a communication system is a system currently considering only a single cell structure and a state in which a subscriber station (SS) (hereinafter referred to as SS) is fixed, that is, no consideration of mobility of the SS is considered. . In contrast, the IEEE 802.16e communication system is a system considering the mobility of the SS in the IEEE 802.16a communication system, and the SS having the mobility is referred to as a mobile terminal (MS). Shall be.

On the other hand, the IEEE 802.16e communication system considers the mobility of the MS, so the power consumption of the MS acts as an important factor of the entire system. Therefore, the MS and the base station (BS) for minimizing the power consumption of the MS are minimized. Hereinafter, a sleep mode operation and an awake mode operation corresponding to the sleep mode operation have been proposed. The sleep mode of the IEEE 802.16e communication system has been proposed to minimize power consumption of the MS in an idle section in which a section in which the packet data is not transmitted when packet data is transmitted. That is, the sleep mode is to minimize the MS power consumption in the idle period in which the packet data is not transmitted by the MS and BS transition to the sleep mode at the same time.

In general, since the packet data has a burst characteristic, it is unreasonable to operate the same as a section in which packet data is transmitted even in a section in which the packet data is not transmitted. will be. On the contrary, when the BS and the MS are in the sleep mode and packet data to be transmitted is generated, both the BS and the MS must simultaneously transmit to the awake mode to transmit and receive the packet data. This sleep mode operation is proposed not only in terms of power consumption but also as a method for minimizing interference between channel signals. However, since the characteristics of the packet data are greatly influenced by traffic, the sleep mode operation should be made organically in consideration of the traffic characteristics and transmission scheme characteristics of the packet data.

Then, the schemes currently proposed in the IEEE 802.16e communication system to support the operation in the sleep mode are as follows.

First, in the IEEE 802.16e communication system, the MS must receive an operation mode transition permission from the BS in order to transition to the sleep mode, and the BS also allows the MS to transition to the sleep mode. In addition, the BS should inform the presence or absence of packet data to be transmitted to the MS during the listening interval (LISTENING INTERVAL, hereinafter referred to as 'LISTENING INTERVAL') of the MS, wherein the MS is in a sleep mode during the LISTENING INTERVAL. Awake to check whether there is packet data to be transmitted from the BS to itself. If the MS detects that there is packet data to be transmitted from the BS to the MS itself, the MS transitions into an awake mode and receives the packet data from the BS. If the MS detects that there is no packet data to be transmitted from the BS to the MS, the MS returns to the sleep mode.

Here, the parameters required to support the sleep mode and awake mode operation will be described.

(1) SLeep IDentifier (SLPID)

The sleep identifier proposed by the IEEE 802.16e communication system is allocated through a sleep response (MOB_SLP-RSP: Mobile_Sleep-Response, hereinafter 'MOB_SLP-RSP') message during the MS transition to the sleep mode. This value is unique to MSs in sleep mode. That is, the sleep identifier is an identifier used to distinguish the MS in the sleep mode including the LISTENING INTERVAL. When the MS transitions to the awake mode, the sleep identifier in use is reduced to the BS and the MS is about to transition to the sleep mode. May be reused through the MOB_SLP-RSP message. In this case, the sleep identifier has a size of 10 bits, thereby supporting MSs performing 1024 sleep mode operations.

(2) Sleep interval (SLEEP INTERVAL, hereinafter referred to as 'SLEEP INTERVAL')

The SLEEP INTERVAL is an interval requested by the MS and allocated by the BS according to the MS's request. A time interval for maintaining the sleep mode until the LISTENING INTERVAL starts after the MS transitions to the sleep mode ) And consequently defined as the time the MS is in sleep mode.

The MS may be in a sleep mode continuously when there is no data to be transmitted from the BS to the MS even after the SLEEP INTERVAL. In this case, an initial sleep window (INITIAL-SLEEP WINDOW) and a final sleep window ( The SLEEP INTERVAL is increased while using the FINAL-SLEEP WINDOW) value. Here, the initial sleep window value represents the initial minimum value of the SLEEP INTERVAL, and the final sleep window value represents the final maximum value of the SLEEP INTERVAL. In addition, the initial sleep window value and the last sleep window value may be represented by the number of frames.

On the other hand, the LISTENING INTERVAL is a period that is requested by the MS, and can be allocated by the BS according to the MS's request. The LISTENING INTERVAL is synchronized with the downlink signal of the BS after the MS wakes up for a while in the sleep mode. Link time, e.g., a time period for receiving downlink messages, such as a Mobile Traffic Indication (MOB_TRF-IND) (hereinafter referred to as "MOS_TRF-IND") message. The MOB_TRF-IND message is a message indicating whether a traffic message to be transmitted to the MS exists, that is, a message indicating whether packet data to be transmitted to the MS exists.

The MS continues to receive the MOB_TRF-IND message during the LISTENING INTERVAL, if the MS is indicated by a value indicating a positive indication in the MOB_TRF-IND message, the awake mode continues. The result is a transition to the awake mode. On the contrary, if the MS is indicated by a value indicating a negative indication in the MOB_TRF-IND message, the MS transitions back to the sleep mode.

(3) Sleep interval update algorithm (SLEEP INTERVAL UPDATE ALGORITHM, hereinafter referred to as 'SLEEP INTERVAL UPDATE ALGORITHM')

When the MS transitions to the sleep mode, the MS determines the sleep interval by considering the preset minimum window value as the minimum sleep mode period. Then, after the MS wakes up from the sleep mode during the LISTENING INTERVAL and confirms that there is no packet data to be transmitted from the BS, the SLEEP INTERVAL is set to twice the value of the previous SLEEP INTERVAL and continues in the sleep mode. . For example, when the minimum window value is '2', the MS is in the sleep mode for the two frames after setting the SLEEP INTERVAL to two frames. After the two frames have elapsed, the MS wakes up from the sleep mode and determines whether the MOB_TRF-IND message is received. If the MOB_TRF-IND message is not received, that is, there is no packet data transmitted from the BS to the MS. If it is determined that the SLEEP INTERVAL is set to 4 frames twice the 2 frames, the SLEEP INTERVAL is in the sleep mode for the 4 frames. The increase of the SLEEP INTERVAL is possible within the maximum window value from the minimum window value, and the update algorithm of the SLEEP INTERVAL is the SLEEP INTERVAL UPDATE ALGORITHM.

1 is a diagram schematically illustrating a sleep mode operation in a general IEEE 802.16e communication system. 1 is a diagram illustrating a sleep mode operation of an MS in which an initial sleep interval is 4 frames and a listening interval is set to 6 frames.

Referring to FIG. 1, the MS 100 is in a sleep mode during the initial SLEEP INTERVAL 101 of 4 frames, and there is packet data to be transmitted from the BS in the LISTENING INTERVAL 102 that first wakes up from the sleep mode. Receive MOB_TRF-IND message 113 indicating no, i.e., a negative indication. After the LISTENING INTERVAL 102 is finished, the MS 100 remains in sleep mode for 8 frames of SLEEP INTERVAL 105 which is twice the initial SLEEP INTERVAL 101. After the SLEEP INTERVAL 105 is finished, when the LISTENING INTERVAL 107 receives the MOB_TRF-IND message 115 indicating a negative indication again, the SLEEP INTERVAL 109 of 16 frames after the LISTENING INTERVAL 107 is finished. In sleep mode. The MS 100 receives a MOB_TRF-IND message 117 indicating that there is packet data to be transmitted from the BS in the LISTENING INTERVAL 111 following the SLEEP INTERVAL 109 of the 16 frames, that is, indicating a positive indication. End the sleep mode operation.

Meanwhile, if the MOB_TRF-IND message is not received from the BS in the listening intervals 103, 107, and 111, the MS 100 determines that the sleep synchronization with the BS is an error and terminates the sleep mode operation. For example, after the MS 100 sleeps at 8 frames of SLEEP INTERVAL 105, the SLEEP INTERVAL UPDATE ALGORITHM malfunctions and 8 frames other than 16 frames are not displayed at SLEEP INTERVAL 109 following LISTENING INTERVAL 107. The sleep operation is performed, and the LISTENING INTERVAL 111 does not receive the MOB_TRF-IND message sent from the BS. Accordingly, since the MS 100 does not receive the MOB_TRF-IND message, it determines that the sleep synchronization with the BS is an error and terminates the sleep mode operation.

The MOB_TRF-IND message format received by the MS from the BS in the LISTENING INTERVAL is shown in Table 1 below.

In the MOB_TRF-IND message, the MOB_TRF-IND message indicates whether the MOB_TRF-IND message is based on an indication bitmap or a sleep identifier based on a 1-bit FMT field. Indicates that the MS has data to send to the specific MS, that is, indicate the positive indication value. In other words, when the FMT field is '0', only the corresponding MS to be represented as a positive indication value is set by setting a bit corresponding to a traffic indication bitmap to '1', and the FMT field is '1'. ', Indicates the sleep identifier of the MS to be represented as a positive indication.

The sleep identifier group indication bitmap field is present only when the FMT is 0, and indicates a set of indication indices allocated one bit to groups composed of 32 sleep identifier units to distinguish MSs transitioning to the sleep mode. One bit allocated to the sleep identifier group indicates the presence or absence of data to be transmitted from the BS to an MS having a sleep identifier belonging to the sleep identifier group. That is, in the sleep identifier group indication bitmap, all MSs having a sleep identifier belonging to the sleep identifier group indicated by '0' are indicated by a negative indication, and a sleep identifier belonging to the sleep identifier group indicated by '1' is indicated. For MSs with at least one MS is indicated as positive. The terminal of the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap may determine whether it is a positive indication through the traffic indication bitmap.

The traffic indication bitmap exists only when the FMT field is 0, and indicates a set of indication indices assigned to sleep identifiers in the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap. In the traffic indication bitmap, the sleep identifier indicated by '0' is indicated as being negative, and the sleep identifier indicated by '1' is indicated as being indicated as a positive indication. Therefore, when the MS in the sleep mode receives the MOB_TRF-IND message with the FMT field of '0' during the LISTENING INTERVAL, '0' is set in the sleep identifier group indication bitmap field indicating the sleep identifier group to which the sleep identifier belongs. If a negative indication indicates a transition to the sleep mode, and if '1' is set, the bit mapped to the MS is checked in the traffic indication bitmap mapped to the sleep identifier group. Transition, and if the positive indication to '1' transitions to the awake mode.

The Num-pos field (Number of Positive indication) is present only when the FMT field is 1, and indicates the total number of sleep identifiers to be informed of the positive indication. The Num-pos field indicates the sleep identifier that should be indicated by a positive indication. Therefore, when the MS in the sleep mode receives the MOB_TRF-IND message with the FMT of '1' during the LISTENING INTERVAL, the MS transitions to the awake mode if its sleep identifier is displayed, and to the sleep mode if it is not displayed.

The TLV encoded items field may include a slip identifier update (SLPID_Update) field. The identifier update field is a field used when it is necessary to change a sleep identifier among MSs receiving a negative indication. Therefore, when the MS in the sleep mode receives a MOB_TRF-IND message indicating a negative indication during the LISTENING INTERVAL, the MS checks the sleep identifier update field and reflects the updated sleep identifier.

The MOB_TRF-IND message is a broadcasting message transmitted by a BS to all MSs present in a cell managed by the BS in a broadcasting manner, and thus, MSs receiving the MOB_TRF-IND message are positively instructed to themselves. If it is not indicated as a value, it is recognized as a negative indication value. In other words, when the MS receives a plurality of MOB_TRF-IND messages from the BS in the LISTENING INTERVAL, the MS determines that the sleep synchronization with the BS is normal if the MS does not indicate itself as a positive indication. do.

On the other hand, when there are a plurality of MSs in the sleep mode, when the sleep synchronization between the BS and a specific MS has an error, when the specific MS does not receive the MOB_TRF-IND message corresponding to the MS from the BS, the MS sends to another MS. The corresponding MOB_TRF-IND message may be determined as the corresponding MOB_TRF-IND message. At this time, the BS transmits data after transmitting a MOB_TRF-IND message indicating that there is data to be transmitted to the MS, that is, a positive indication to the MS, but the MS sends a MOB_TRF-IND message indicating a positive indication. Because it did not receive, it is still in sleep mode and data loss occurs. Hereinafter, with reference to Figure 2 will be described in more detail.

2 is a diagram schematically illustrating a sleep mode operation of a system including two MSs serviced by one BS in a general IEEE 802.16e communication system. FIG. 2 is a diagram illustrating sleep mode operations of MSs in which initial SLEEP INTERVAL is 4 frames and LISTENING INTERVAL is set to 6 frames.

Referring to FIG. 2, the MSs 200 and 250 have initial SLEEP INTERVAL and LISTENING INTERVAL set to the same state as described above, except that the sleep mode operation points are different. That is, the MS1 200 performs a sleep mode operation before the MS2 250. The MS1 200 is in a sleep mode during the initial SLEEP INTERVAL 201 of four frames set at a predetermined start time, and there is no packet data to be transmitted from the BS in the listening interval 203 which first wakes up from the sleep mode. Receive MOB_TRF-IND message 213 indicating a negative indication that no. When the LISTENING INTERVAL 203 is finished, the MS1 200 is in a sleep mode for 8 frames of SLEEP INTERVAL 205, which is twice the initial SLEEP INTERVAL 201. After the end of the SLEEP INTERVAL 205, when the LISTENING INTERVAL 207 receives the MOB_TRF-IND message 215 indicating the negative indication again, the SLEEP INTERVAL of 16 frames after the LISTENING INTERVAL 207 ends. 209) in sleep mode. The MS1 200 receives a MOB_TRF-IND message 217 indicating that there is no packet data to be transmitted from the BS in the LISTENING INTERVAL 211 following the SLEEP INTERVAL 209 of the 16 frames. Is in sleep mode.

In addition, the MS2 250 is in the sleep mode for the initial SLEEP INTERVAL 251 of four frames, that is, four frames of the SLEEP INTERVAL already set at a different starting point from the MS1 200, and is first LISTENING waking from the sleep mode. At INTERVAL 253, a MOB_TRF-IND message 265 is received indicating that there is no packet data to be transmitted from the BS, i.e., indicating a negative indication. When the LISTENING INTERVAL 253 ends, the MS2 250 is in a sleep mode for eight frames of SLEEP INTERVAL 255, which is twice the initial SLEEP INTERVAL 201. After the SLEEP INTERVAL 255 ends, when the LISTENING INTERVAL 257 receives the MOB_TRF-IND message 267 indicating a negative indication again, the LISTENING INTERVAL 257 ends in the sleep mode.

At this time, the aforementioned SLEEP INTERVAL UPDATE ALGORITHM malfunctions and is present in the sleep mode for 8 frames instead of 16 frames in the SLEEP INTERVAL 259 following the LISTENING INTERVAL 257. Next, in the LISTENING INTERVAL 261, the MS2 250 may receive a MOB_TRF-IND message 217 indicating the negative indication corresponding to the MS1 200 since the MOB_TRF-IND message is a broadcasting message. The MS2 250 that receives the MOB_TRF-IND message 217 indicating the negative indication corresponding to the MS1 200 from the BS is in the sleep mode during the SLEEP INTERVAL 263 of 8 frames. Then, the MS2 250 does not receive a MOB_TRF-IND message 269 indicating a positive indication that there is packet data to be transmitted from the BS in the SLEEP INTERVAL 263.

That is, when the MS2 250 receives the MOB_TRF-IND message 217 indicating the negative indication corresponding to the MS1 200 in the listening INTERVAL 261, the MS2 250 is in the sleep mode in the SLEEP INTERVAL 263 and thus receives the MS2 250 from the BS. Does not receive a MOB_TRF-IND message 269 indicating a positive indication corresponding to. Accordingly, the BS transmits data 271 after transmitting the MOB_TRF-IND message 269 indicating the positive indication, but the MS2 250 is in the sleep mode, so that the BS transmits the data 271 transmitted by the BS. I do not receive it. That is, data loss occurs between the MS2 250 and the BS. As described above, since the MSs do not correctly recognize whether the MOB_TRF-IND message received from the BS is the MOB_TRF-IND message corresponding to the MS in the BWA communication system, an error occurs during the sleep mode operation, thereby causing data loss.

Accordingly, an object of the present invention is to provide a sleep mode operation method and system of a communication system in a BWA communication system.

Another object of the present invention is to provide a method and system for configuring and transmitting a MOB_TRF-IND message for accurate sleep mode operation of a communication system in a BWA communication system.

The method of the present invention for achieving the above object, in the sleep mode operation method in a broadband wireless access communication system, when receiving a sleep mode transition request message from the mobile terminal, and confirms the operation mode of the mobile terminal, As a result of the checking, a process of detecting mobile terminals to transition from the sleep mode to the awake mode, the presence or absence of data to be transmitted to the detected mobile terminals, and grouping each of the mobile terminals according to the test result, Setting first information corresponding to the grouping in the traffic indication message; setting second information in the traffic indication message according to the set first information, and setting the first information and the second information And transmitting the indication message to the mobile terminals.

According to another aspect of the present invention, there is provided a sleep mode operation method in a broadband wireless access communication system, when receiving a traffic indication message from a base station, checking a FMT field set in the traffic indication message; And confirming the presence of the traffic indication information and the data to be transmitted from the base station corresponding to the checked FMT field, and performing a predetermined operation corresponding to the check result.

The system of the present invention for achieving the above object, in a sleep mode operation system in a broadband wireless access communication system, when receiving a sleep mode transition request message from the mobile terminals, confirms the operation mode of the mobile terminals, As a result of checking, after detecting the mobile terminals to transition from the sleep mode to the awake mode, it is checked whether there is data to be transmitted to the detected mobile terminals, grouping each of the mobile terminals according to the test result, and then grouping the mobile terminals. First information corresponding to the traffic indication message is set, second information is set in the traffic indication message corresponding to the set first information, and the traffic indication message is set with the first information and the second information. A base station for transmitting to mobile terminals and a traffic indication message from the base station; Checking the FMT field set in the traffic indication message, and confirms the presence of its own traffic indication information and the data to be transmitted from the base station corresponding to the confirmed FMT field and performs a predetermined operation corresponding to the check result It is characterized by including.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present invention.

The present invention relates to a mobile station (MS) in a broadband wireless access (BWA) communication system, such as an Institute of Electrical and Electronics Engineers (IEEE) 802.16e communication system. MS sleep method (SLEEP MODE) operation method and system of the present invention). In addition, the present invention accurately receives and recognizes downlink messages corresponding to the BS from the BS in the BWA communication system, for example, a Mobile Traffic Indication (MOB_TRF-IND) message. We propose a method and system for operating in a sleep mode.

The IEEE 802.16e communication system is referred to as Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Frequency Division Multiple Access (OFDMA). As a broadband wireless access communication system using the method, high-speed data transmission is possible by transmitting a physical channel signal using a plurality of sub-carriers, and supports a multi-cell structure It is a communication system supporting MS mobility. Although the present invention will be described using the IEEE 802.16e communication system as an example, the present invention is applicable to all communication systems supporting the sleep mode as well as the IEEE 802.16e communication system.

First, to support the sleep mode operation between the MS and the base station (BS: hereinafter referred to as 'BS') and the awake mode operation corresponding to the sleep mode operation to minimize power consumption of the MS. The parameters required to do this are described below.

(1) SLeep IDentifier (SLPID)

The sleep identifier proposed by the IEEE 802.16e communication system is allocated through a sleep response (MOB_SLP-RSP: Mobile_Sleep-Response, hereinafter 'MOB_SLP-RSP') message during the MS transition to the sleep mode. This value is unique to MSs in sleep mode. That is, the sleep identifier is an identifier used to distinguish the MS in the sleep mode including the listening interval (LISTENING INTERVAL, hereinafter referred to as 'LISTENING INTERVAL'), and when the MS transitions to the awake mode, The sleep identifier may be reduced to the BS to be reused through the MOB_SLP-RSP message to the MS to transition to the sleep mode. In this case, the sleep identifier has a size of 10 bits, thereby supporting MSs performing 1024 sleep mode operations.

(2) Sleep interval (SLEEP INTERVAL, hereinafter referred to as 'SLEEP INTERVAL')

The SLEEP INTERVAL is an interval requested by the MS and allocated by the BS according to the MS's request. A time interval for maintaining the sleep mode until the LISTENING INTERVAL starts after the MS transitions to the sleep mode ) And consequently defined as the time the MS is in sleep mode.

The MS may be in a sleep mode continuously when there is no data to be transmitted from the BS to the MS even after the SLEEP INTERVAL. In this case, an initial sleep window (INITIAL-SLEEP WINDOW) and a final sleep window ( The SLEEP INTERVAL is increased while using the FINAL-SLEEP WINDOW) value. Here, the initial sleep window value represents the initial minimum value of the SLEEP INTERVAL, and the final sleep window value represents the final maximum value of the SLEEP INTERVAL. The initial sleep window value and the last sleep window value may be represented by the number of frames.

On the other hand, the LISTENING INTERVAL is a period that is requested by the MS, and can be allocated by the BS according to the MS's request. The LISTENING INTERVAL is synchronized with the downlink signal of the BS after the MS wakes up for a while in the sleep mode. Link time, e.g., a time period for receiving downlink messages, such as a Mobile Traffic Indication (MOB_TRF-IND) message (hereinafter referred to as MOB_TRF-IND) message. The MOB_TRF-IND message is a message indicating whether a traffic message to be transmitted to the MS exists, that is, a message indicating whether packet data to be transmitted to the MS exists.

The MS continues to receive the MOB_TRF-IND message during the LISTENING INTERVAL, if the MS is indicated by a value indicating a positive indication in the MOB_TRF-IND message, the awake mode continues. The result is a transition to the awake mode. On the contrary, if the MS is indicated by a value indicating a negative indication in the MOB_TRF-IND message, the MS transitions back to the sleep mode. If the MOB_TRF-IND message does not indicate any indication to the MS, the MS ignores the received MOB_TRF-IND message and waits for another MOB_TRF-IND message.

(3) Sleep interval update algorithm (SLEEP INTERVAL UPDATE ALGORITHM, hereinafter referred to as 'SLEEP INTERVAL UPDATE ALGORITHM')

When the MS transitions to the sleep mode, the MS determines the sleep interval by considering the preset minimum window value as the minimum sleep mode period. Then, after the MS wakes up from the sleep mode during the LISTENING INTERVAL and confirms that there is no packet data to be transmitted from the BS, the SLEEP INTERVAL is set to twice the value of the previous SLEEP INTERVAL and continues in the sleep mode. . For example, when the minimum window value is '2', the MS is in the sleep mode for the two frames after setting the SLEEP INTERVAL to two frames. After the two frames have elapsed, the MS wakes up from the sleep mode and determines whether the MOB_TRF-IND message is received. If the MOB_TRF-IND message is not received, that is, there is no packet data transmitted from the BS to the MS. If it is determined that the SLEEP INTERVAL is set to 4 frames twice the 2 frames, the SLEEP INTERVAL is in the sleep mode for the 4 frames. The increase of the SLEEP INTERVAL is possible within the maximum window value from the minimum window value, and the update algorithm of the SLEEP INTERVAL is the SLEEP INTERVAL UPDATE ALGORITHM.

In addition, the messages currently defined in the IEEE 802.16e communication system to support the sleep mode operation and the awake mode operation as described above are as follows.

(1) Sleep Request (MOB_SLP-REQ: Mobile_Sleep-Request, hereinafter referred to as MOB_SLP-REQ) message

The MOB_SLP-REQ message is a message transmitted from the MS to the BS, and the MS requests a transition to the sleep mode. The MOB_SLP-REQ message includes parameters required for the MS to operate in a sleep mode, that is, information elements (IEs). The MOB_SLP-REQ message is a dedicated message transmitted based on a connection identifier (CID: connection ID, hereinafter referred to as 'CID') of the MS. Each of the information elements of the MOB_SLP-REQ message is described as follows.

First, a MANAGEMENT MESSAGE TYPE field is information indicating what message is currently transmitted. The INITIAL-SLEEP WINDOW field indicates the start value required for the SLEEP INTERVAL, and the FINAL-SLEEP WINDOW field indicates the end value required for the SLEEP INTERVAL. That is, as described in the SLEEP INTERVAL UPDATE ALGORITHM, the SLEEP INTERVAL can be updated within the final window value from the initial window value. The LISTENING INTERVAL field indicates a required LISTENING INTERVAL, and the LISTENING INTERVAL may also be indicated by a frame value.

(2) MOB_SLP-RSP message

The MOB_SLP-RSP message is a response message to the MOB_SLP-REQ message, and is used as a message indicating whether to allow or reject the transition to the sleep mode requested by the MS or provide an unsolicited instruction. Can also be used as an indication message. The MOB_SLP-RSP message includes information elements necessary for the MS to operate in a sleep mode. The MOB_SLP-RSP message is also a dedicated message transmitted based on a basic CID of the MS. Each of the information elements of the MOB_SLP-RSP message will be described below.

First, the management message type field is information indicating what message is currently transmitted. In addition, the SLEEP-APPROVED field is represented by 1 bit, and when the sleep permission value is' 0 ', it indicates that the transition to the sleep mode is rejected (SLEEP-MODE REQUEST DENIED), and the sleep permission value is' 1 'indicates that transition to the sleep mode is allowed (SLEEP-MODE REQUEST APPROVED). On the other hand, when the sleep permission value is '0', it indicates that the transition to the sleep mode requested by the MS has been rejected by the BS, and the MS which has been rejected sends the MOB_SLP-REQ message according to the condition. Send to BS or wait for MOB_SLP-RSP message indicating unsolicited indication from BS. When the slip permission value is '1', there is a START FRAME field, an initial sleep window field, a last sleep window field, a LISTENING INTERVAL field, and a sleep identifier field described above. When the slip permission value is '0', there is an AFTER-REQ-Action field and a RE-Duration field.

Here, the start frame field is a least significant bit (LSB) of a 6-bit frame of the frame until the MS enters the first SLEEP INTERVAL. The MS is referred to as the MOB_SLP-. The sleep frame transitions to the start frame of the RSP message. The sleep identifier is used to distinguish MSs in a sleep mode and may identify MSs in a total of 1024 sleep modes.

Meanwhile, as described above, the initial sleep window field indicates a start value for the sleep interval, and the LISTENING INTERVAL field indicates a value for LISTENING INTERVAL. The last sleep window field is used for calculating an end value for the sleep interval in the aforementioned sleep interval update algorit. The re-request action field indicates an action that the MS should take when the transition to the sleep mode is denied.

(3) MOB_TRF-IND message

The MOB_TRF-IND message is a message transmitted by the BS to the MS during the LISTENING INTERVAL and indicates that there is packet data to be transmitted to the MS by the BS. The format of the MOB_TRF-IND message according to the present invention is shown in Table 2 below.

The MOB_TRF-IND message is a broadcasting message that is transmitted in a broadcasting manner unlike the MOB_SLP-REQ message and the MOB_SLP-RSP message. The MOB_TRF-IND message is a message indicating whether there is packet data to be transmitted from the BS to a predetermined MS, and the MS decodes the broadcast MOB_TRF-IND message during the LISTENING INTERVAL and transitions to an awake mode. Decide whether to return to sleep mode.

Then, each of the information elements of the MOB_TRF-IND message according to the present invention shown in Table 2 as follows.

First, the management message type field is information indicating what message is currently being transmitted. When the management message type is 52 (MANAGEMENT MESSAGE TYPE = 52), the management message type field indicates the MOB_TRF-IND message. The FMT field is 1 bit in the above-described MOB_TRF-IND message of Table 1, but is represented by 2 bits in the MOB_TRF-IND message according to the present invention. The first bit of the FMT field, that is, the most significant bit (MSB), indicates whether the MOB_TRF-IND message is a value indicating a positive indication or a negative indication. The second bit, i.e., the next bit after the MSB, indicates whether the MOB_TRF-IND message is a message based on an indication bitmap or a message based on a sleep identifier.

That is, when the FMT field is '00', only a corresponding MS to be indicated as a positive indication is set to a bit corresponding to the MS in the traffic indication bitmap field, that is, a positive traffic indication bitmap field. It is set to '. In addition, when the FMT field is '01', only the corresponding MS to be displayed as a positive indication is indicated in the SLPID Group Indication bit-map field, and when the FMT field is '10', it is indicated as a negative indication. Only the corresponding MS should be set to '1' in the traffic indication bitmap field, that is, the negative traffic indication bitmap field. When the FMT field is '11', only the corresponding MS to be indicated by the negative indication is indicated in the sleep identifier group indication bitmap field.

In more detail, the sleep identifier group indication bitmap field is present only when the FMT field is 00 or 01, and is allocated one bit to groups composed of 32 sleep identifier units to distinguish MSs transitioning to sleep mode. Represents a set of indicated indexes. One bit allocated to the sleep identifier group indicates the presence or absence of data to be transmitted from the BS to an MS having a sleep identifier belonging to the sleep identifier group.

If the FMT field is 00, all of the MSs with a sleep identifier belonging to the sleep identifier group indicated by '0' have no indication in the sleep identifier group indication bitmap. For MSs with belonging sleep identifier, at least one MS is marked as positive. The terminal of the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap may determine whether it is a positive indication through the positive traffic indication bitmap.

If the FMT field is 01, in the sleep identifier group indication bitmap, all the MSs with sleep identifiers belonging to the sleep identifier group indicated by '0' have no indication, and the sleep identifier group indicated by '1' For MSs with belonging sleep identifier, at least one MS is indicated as negative. The terminal of the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap may determine whether it is a negative indication through the negative traffic indication bitmap.

The positive traffic indication bitmap exists only when the FMT field is 00, and indicates a set of indication indices assigned to sleep identifiers in the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap. The sleep identifier indicated by '0' in the traffic indication bitmap indicates that there is no indication, and the sleep identifier indicated by '1' indicates that it is indicated as a positive indication.

The negative traffic indication bitmap exists only when the FMT field is 01, and indicates a set of indication indices assigned to sleep identifiers in the sleep identifier group indicated by '1' in the sleep identifier group indication bitmap. The sleep identifier indicated by '0' in the traffic indication bitmap indicates that there is no indication, and the sleep identifier indicated by '1' indicates that it is indicated as a negative indication.

The Num-pos field (Number of Positive indication) is present only when the FMT field is 10, and indicates the total number of sleep identifiers to be informed of the positive indication. The Num-pos field indicates the sleep identifier that should be indicated by a positive indication. The Num-nos field (Number of Negative indication) is present only when the FMT field is 11, and indicates the total number of sleep identifiers that should be known as negative indications. The Num-nos field is followed by a sleep identifier that should be indicated by a negative indication.

The TLV encoded items field may include a slip identifier update (SLPID_Update) field and a sleep identifier indication (SLPID_Ind). The identifier update field is a field used when it is necessary to change a sleep identifier among MSs receiving a negative indication. The sleep identifier indication field is used to add a sleep identifier that must indicate a negative or positive indication in addition to the positive or negative indication determined by the FMT value. That is, a slip identifier indicating a negative indication at the same time is added to a MOB_TRF-IND indicating a positive indication as 00 or 10, or a sleep identifier indicating a positive indication at the same time as a MOB_TRF-IND indicating a negative indication as 01 or 11 can do.

If the MS in the sleep mode receives the MOB_TRF-IND message during LISTENING INTERVAL and the FMT field is '00', the MS in the sleep identifier group indication bitmap field for the group including the sleep identifier for the MS is received. If '0' is set, it indicates that there is no indication to the MS and ignores the MOB_TRF-IND message. On the other hand, if '1' is set in the sleep identifier group indication bitmap field, it indicates that at least one MS of the sleep identifier group is indicated as a positive indication, so that the corresponding MS has a bit corresponding to itself in the positive traffic indication bitmap. If the value is set to '1' in the positive traffic indication bitmap field, the signal indicates a positive indication value and transitions to the awake mode. In addition, if '0' is set in the positive traffic message bitmap field, it indicates that there is no indication and ignores the MOB_TRF-IND message. At this time, even if there is no indication for the MS, if a sleep identifier is indicated as a TLV encoding item and if the item includes a sleep identifier for the MS, a transition to the sleep mode is indicated since a negative indication for the MS is indicated.

On the other hand, if the FMT field is '01', the MS checks whether there is a sleep identifier for itself among the sleep identifiers following the Num-pos field, and if the sleep identifier exists, indicates a positive indication and thus, enters the awake mode. If the transition is not present and there is no indication, the MOB_TRF-IND message is ignored. At this time, even if there is no indication for the MS, if there is a sleep identifier indication as a TLV encoding item and a sleep identifier for the MS is included therein, a negative indication for the MS is indicated, so that the terminal transitions to the sleep mode.

In addition, when the FMT field is '10', if '0' is set in the sleep identifier group indication bitmap field for the group including the sleep identifier for the MS, it indicates that there is no indication for the MS. Ignore the MOB_TRF-IND message. On the other hand, if '1' is set in the sleep identifier group indication bitmap field, it indicates that at least one MS of the sleep identifier group is indicated by a negative indication, and thus, a bit corresponding to itself is checked in the negative traffic indication bitmap. If the negative traffic indication bitmap field is set to '1', it indicates a negative indication value and transitions to sleep mode. If the negative traffic indication bitmap field is set to '0', there is no indication, so the MOB_TRF-IND message Ignore At this time, even if there is no indication for the MS, if there is a sleep identifier indication as a TLV encoding item, and if the item includes a sleep identifier for the MS, the terminal indicates a positive indication for the MS and then transitions to the awake mode. In addition, in the case of a negative indication, if there is a sleep identifier update as a TLV encoding item, and an update for the MS is displayed in the item, the sleep identifier update is performed.

On the other hand, if the FMT field is '11', the MS checks whether there is a sleep identifier for itself among the sleep identifiers following the Num-nos field, and if the sleep identifier exists, a negative indication indicates that the MS transitions to the sleep mode. If it does not exist, it indicates that there is no indication and ignores the MOB_TRF-IND message. In this case, even if there is no indication for the MS, if there is a sleep identifier indication as a TLV encoding item and a slip identifier for the MS is included in the TLV encoding item, the terminal indicates a positive indication and then transitions to the awake mode. In addition, in the case of a negative indication, if there is a sleep identifier update as a TLV encoding item and an update for the MS is displayed therein, the sleep identifier update is performed.

The BS generating the MOB_TRF-IND message as described above and transmitting to each MS checks whether there is data to be transmitted for all MSs in the sleep mode entering the LISTENING INTERVAL after the SLEEP INTERVAL. If there is data to be transmitted as a result of the confirmation, the BS stores a sleep identifier of the MS indicating a positive indication to the corresponding MS to which the data is to be transmitted, whereas if there is no data to be transmitted, the BS indicates a negative indication to the corresponding MS. Stores the sleep identifier of the MS to indicate. That is, the BS performs the above operation on the MSs in all the sleep modes entering the LISTENING INTERVAL, and then determines the most optimal MOB_TRF-IND message format corresponding to the number of each indication to each MS. send.

For example, assuming that sending the smallest message is the best selection criterion, determine the number of MSs that should be represented by the positive and negative indications, then calculate the size of the message according to the format of each message to determine the smallest size. Configure the message by determining the message format. In other words, when there are many MSs to be indicated as positive indications, the MSs to be indicated as positive indications are indicated by setting the FMT field of the MOB_TRF-IND message to '00' or '01', and then negative through the slip identifier indication field of the TLV encoded item. Indicates MSs to be indicated. On the other hand, if there are many MSs to be indicated by the negative indication, the MSs to be indicated by the negative indication are indicated by the FMT field '10' or '11', and then indicated by the positive indication through the sleep identifier indication field of the TLV encoded item. Indicates MSs. In addition, when a sleep identifier update is required, a sleep identifier update field of the TLV encoding item may be added.

3 is a diagram illustrating an operation process of a BS in a BWA communication system according to an embodiment of the present invention. 3 is a diagram illustrating an operation process of a BS providing a service to an MS in a sleep mode and illustrating a process of configuring the above-described MOB_TRF-IND message.

Referring to FIG. 3, in step 301, the BS checks whether there is an MS in which SLEEP INTERVAL ends, that is, a LISTENING INTERVAL, among MSs in the sleep mode as previously assumed in every frame. If there is an MS in which SLEEP INTERVAL ends in step 301, the MS checks whether there is data to be transmitted to the MS in which SLEEP INTERVAL ends. If there is data to be transmitted as a result of the checking, the process proceeds to step 305 to increase the number of positive instructions, thereby indicating the MS in which the data to be transmitted is indicated as a positive indication in the MOB_TRF-IND message. Thereafter, the process proceeds to step 301 again to check whether there is an MS in which SLEEP INTERVAL is terminated among MSs in the sleep mode. If there is no data to transmit in step 303, the flow proceeds to step 307 to increase the number of negative instructions and then proceeds to step 309. After the SLEEP INTERVAL is updated by the SLEEP INTERVAL UPDATE ALGORITHM described above in step 309, the process proceeds to step 301. Here, the above-described process is performed for all MSs in the sleep mode.

On the other hand, if there is no MS for which the SLEEP INTERVAL is terminated as a result of checking in step 301, the process proceeds to step 311 to check whether both the number of positive instructions and the number of negative instructions are '0'. If all of the check results are '0', since all MSs exist as SLEEP INTERVAL in the corresponding frame, the operation of generating the MOB_TRF-IND message is terminated by ending the sleep operation of the corresponding frame. On the other hand, if there is at least one positive instruction or negative instruction in step 311, the process proceeds to step 313 to compare the number of positive instructions and the number of negative instructions. In this case, if the number of positive instructions is greater than the number of negative instructions, the process proceeds to step 315. In step 315, the FMT field of the MOB_TRF-IND message is set to 00 or 01. Then, in step 317, the MOB_TRF-IND message with the FMT field set is transmitted to the MS. If the number of negative instructions is greater than the number of positive instructions in step 313, the process proceeds to step 319. In step 319, the FMT field of the MOB_TRF-IND message is set to 10 or 11. Then, in step 321, the MOB_TRF-IND message with the FMT field set is transmitted to the MS.

The MS presenting the LISTENING INTERVAL in the sleep mode receives a MOB_TRF-IND message configured as described above from the BS to determine whether it is a positive indication, that is, transition from sleep mode to awake mode, or negative, i.e. again, Confirm that you want to transition to sleep mode. In more detail, when the FMT field receives a MOB_TRF-IND message indicating a positive indication as '00' or '01' from the BS, the MS sends a positive indication to the positive traffic indication bitmap of the MOB_TRF-IND message. If so, the BS recognizes that there will be data to send to it and transitions from sleep mode to awake mode. If it is negatively indicated in the sleep identifier indication field of the TLV coded code, the terminal transitions to the sleep mode.

In addition, when the FMT field receives a MOB_TRF-IND message indicating a negative indication as '10' or '11' from the BS, the MS indicates that the BS indicates that the negative traffic indication bitmap of the MOB_TRF-IND message is indicated by the BS. It recognizes that there is no data to transmit to itself and transitions back to sleep mode. If it is displayed positively in the slip identifier indication field of the TLV coded code, the system transitions to the awake mode.

In addition, when the MS does not receive a MOB_TRF-IND message indicating a positive indication or a negative indication until the end of the LISTENING INTERVAL, the MS determines that the sleep synchronization with the BS is an error and terminates the sleep mode operation. At this time, when the MS ends the sleep mode operation, the MS transmits a message requesting a transition to the sleep mode, that is, the aforementioned MOB_SLP-REQ message to the BS. Hereinafter, with reference to Figure 4 will be described in more detail.

4 is a diagram illustrating an operation process of an MS in a BWA communication system according to an exemplary embodiment of the present invention. 4 is a diagram illustrating an operation process of the MS in the sleep mode.

Referring to FIG. 4, when the MS receives the MOB_TRF-IND message during the LISTENING INTERVAL in step 401, the MS checks whether there is a positive indication or a negative indication in the received MOB_TRF-IND message. If there is an indication as a result of the check result, it is checked whether the indication is a positive indication in step 405. On the other hand, if it is determined in step 405 that the negative indication proceeds to step 407, and in step 407, the next SLEEP INTERVAL is calculated through the SLEEP INTERVAL UPDATE ALGORITHM, and if the sleep identifier exists in the slip identifier update field of the TLV coded code, the terminal sleeps. After the identifier is updated, the system transitions to the sleep mode, and the process proceeds to step 401 again in the sleep mode.

On the other hand, if the MOB_TRF-IND message is not received during the LISTENING INTERVAL at step 401, the MS determines that the sleep synchronization with the BS is an error, and proceeds to step 409 to transition to the awake mode, and the MOB_SLP-REQ in the awake mode. Send a message to the BS. In addition, if the positive and negative instructions do not exist in the MOB_TRF-IND message received in step 403, the process proceeds to step 401 again and receives the MOB_TRF-IND message again during LISTENING INTERVAL.

5 is a diagram schematically illustrating a sleep mode operation in a BWA communication system according to an embodiment of the present invention. 5 is a diagram illustrating sleep mode operations of MSs in which the initial sleep interval is 4 frames and the listening interval is equally set to 6 frames.

Referring to FIG. 5, the MSs 500 and 550 have initial SLEEP INTERVAL and LISTENING INTERVAL set to the same state as previously assumed, except that the sleep mode operation points are different. That is, as described above, the start frame field, the initial sleep window field, and the last sleep of the MOB_SLP-RSP message respectively received from the BS corresponding to the MOB_SLP-REQ message transmitted by the MS1 500 and the MS2 550 to the BS. Determined by the value set in the mode field and the LISTENING INTERVAL field. The MS1 500 and the MS2 550 differ only in the value set in the start frame field and have the same value set in other initial sleep window field, last sleep mode field, and LISTENING INTERVAL field.

The MS1 500 is in the sleep mode during the initial SLEEP INTERVAL 501 of 4 frames, that is, the SLEEP INTERVAL of 4 frames at a predetermined start time corresponding to the value set in the start frame field, and wakes up from the sleep mode for the first time. I receive a MOB_TRF-IND message 513 indicating that there is no packet data to be sent to it from the BS at the LISTENING INTERVAL 503. When the LISTENING INTERVAL 503 is finished, the MS1 500 recognizes that there is no packet data to be transmitted to the MS1 500, and sleeps for 8 frames of SLEEP INTERVAL 505 which is twice the initial SLEEP INTERVAL 501. Exists as. After the SLEEP INTERVAL 505 is finished, when the MS1 500 receives the MOB_TRF-IND message 515 indicating a negative indication from the LISTENING INTERVAL 507 again, 16 frames after the LISTENING INTERVAL 507 ends. Is in sleep mode during SLEEP INTERVAL 509. Upon receiving the MOB_TRF-IND message 517 indicating that there is packet data to be transmitted to the BS from the BS in the LISTENING INTERVAL 511 following the SLEEP INTERVAL 509 of the 16 frames, the MS1 ( 500 transitions to the awake mode.

In addition, the MS2 550 enters the sleep mode during the initial SLEEP INTERVAL 551 of four frames, that is, the SLEEP INTERVAL of four frames, at a different starting time point than the MS1 500, that is, corresponding to the value set in the start frame field. A MOB_TRF-IND message 563 is present, indicating that there is no packet data to be sent to it from the BS at the LISTENING INTERVAL 553 waking up in the sleep mode for the first time. When the LISTENING INTERVAL 553 ends, the MS2 550 remains in sleep mode for eight frames of SLEEP INTERVAL 555, which is twice the initial SLEEP INTERVAL 501. After the SLEEP INTERVAL 555 is finished, when the LISTENING INTERVAL 557 receives the MOB_TRF-IND message 567 indicating a negative indication again, the LISTENING INTERVAL 557 ends in the sleep mode.

At this time, the aforementioned SLEEP INTERVAL UPDATE ALGORITHM malfunctions and is present in the sleep mode for 8 frames instead of 16 frames in the SLEEP INTERVAL 559 following the LISTENING INTERVAL 557. In the LISTENING INTERVAL 561 after the SLEEP INTERVAL 559, the MS2 550 indicates the MOB_TRF-IND indicating the positive indication corresponding to the MS1 500 since the MOB_TRF-IND message transmitted from the BS is a broadcasting message. Message 517 may be sent. However, even though the MOB_TRF-IND message 517 indicating the negative indication corresponding to MS1 500 from the BS is transmitted to the MS2 550, the MS2 550 does not display the MOB_TRF-IND message indicating the negative indication. Recognize that there is no value in 517 indicating the corresponding instruction.

That is, even if the MS2 550 receives the MOB_TRF-IND message corresponding to the MS1 500 transmitted from the BS, the MS2 550 indicates an indication corresponding to the MOB_TRF-IND message, that is, a value indicating a negative indication. Or recognize that there is no value indicating a positive indication. Also, since the MS2 550 did not receive the MOB_TRF-IND message from the listening INTERVAL 561, the MS2 550 determines that the sleep synchronization with the BS is an error. In response to the determination result, the MS2 550 terminates the sleep mode operation and transmits a message requesting a transition to the sleep mode, that is, the aforementioned MOB_SLP-REQ message to the BS.

As such, each MS that receives the MOB_TRF-IND message in the BWA communication system according to the present invention correctly distinguishes an indication value corresponding to the MS. In other words, even if a given MS receives a MOB_TRF-IND message indicating an indication value corresponding to another MS from the BS, the message corresponding to itself is accurately distinguished through values set in the received field of the MOB_TRF-IND message.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the present invention can accurately perform the sleep mode operation of the system by accurately recognizing whether each MS is a message corresponding to the traffic indication message transmitted from the BS. Accordingly, data loss due to the sleep mode malfunction of the system can be prevented, and the system can be operated reliably.

Claims (16)

In the sleep mode operation method in a broadband wireless access communication system, Receiving a sleep mode transition request message from the mobile terminals, checking an operation mode of the mobile terminals, and detecting the mobile terminals to transition from the sleep mode to the awake mode as a result of the checking; Checking whether there is data to be transmitted to the detected mobile terminals, grouping each mobile terminal according to the test result, and setting first information corresponding to the grouping in the traffic indication message; And setting second information in the traffic indication message according to the set first information, and transmitting the traffic indication message in which the first information and the second information are set to the mobile terminals. How sleep mode works. The method of claim 1, wherein after grouping the respective mobile terminals, setting the first information corresponding to the grouping in the traffic indication message includes: After first grouping mobile terminals in which the data to be transmitted exists and second grouping of mobile terminals in which the data to be transmitted are not present, the traffic indication message is displayed with first information corresponding to the first group and the second group. The sleep mode operation method characterized in that the setting. The method of claim 2, wherein the setting of the first message corresponding to the first group and the second group in the traffic indication message comprises: And setting the first information to the most significant bit of the FMT field of the traffic indication message. The method of claim 1, wherein the setting of the second information in the traffic indication message corresponding to the set first information comprises: Determining whether the set first information is based on a traffic indication bitmap or a sleep identifier of a mobile terminal, and sets second information corresponding to the result of the check in the traffic indication message; . The method of claim 4, wherein the setting of the second information corresponding to the verification result in the traffic indication message comprises: And setting the second information to the next bit of the most significant bit of the FMT field of the traffic indication message. 6. The method of claim 3, wherein the transmitting of the traffic indication message to which the first information and the second information are set is performed to mobile terminals. And transmitting traffic indication information of mobile terminals corresponding to the first information and the second information set in the FMT field in the traffic indication message. In the sleep mode operation method in a broadband wireless access communication system, Receiving a traffic indication message from a base station, checking a FMT field set in the traffic indication message; And checking whether there is a traffic indication information and data to be transmitted from the base station corresponding to the checked FMT field, and performing a predetermined operation corresponding to the check result. The method of claim 7, wherein the checking of the presence of the traffic indication information and the data to be transmitted from the base station corresponding to the identified FMT field comprises: The presence of data to be transmitted from the base station is checked by checking the most significant bit of the FMT field, and the next bit of the most significant bit of the FMT field is checked to determine whether the traffic indication information is based on a traffic indication bitmap and sleep of the mobile terminal. Sleep mode operation method characterized in that identifying whether the identifier based. The method of claim 7, wherein the performing of the predetermined operation corresponding to the verification result comprises: If there is data to be transmitted from the base station, the operation mode is shifted to the awake mode, if there is no data to be transmitted from the base station sleep mode characterized in that after calculating the sleep interval and transitions to the sleep mode How it works. In the sleep mode operation system in a broadband wireless access communication system, When receiving the sleep mode transition request message from the mobile terminals, the mobile terminal checks the operation mode of the mobile terminals, detects the mobile terminals to transition from the sleep mode to the awake mode, and transmits them to the detected mobile terminals. After checking for the presence of data, grouping each of the mobile terminals according to the test result, and setting the first information corresponding to the grouping in the traffic indication message, the second information corresponding to the set first information. A base station for setting a traffic indication message to the traffic indication message and transmitting a traffic indication message including the first information and the second information to mobile terminals; When receiving the traffic indication message from the base station, checks the FMT field set in the traffic indication message, and confirms the presence of the traffic indication information and the data to be transmitted from the base station corresponding to the confirmed FMT field after the confirmation result And a mobile terminal correspondingly performing a predetermined operation. The method of claim 10, wherein the base station, After first grouping mobile terminals in which the data to be transmitted exists and second grouping of mobile terminals in which the data to be transmitted are not present, the traffic indication message is displayed with first information corresponding to the first group and the second group. Sleep mode operation system, characterized in that set to. The method of claim 11, wherein the base station, And a first information corresponding to the first group and the second group is set in the most significant bit of the FMT field of the traffic indication message. The method of claim 10, wherein the base station, Determine whether the set first information is based on a traffic indication bitmap or a sleep identifier of a mobile terminal, and sets second information corresponding to the result of the check in the traffic indication message; system. The method of claim 13, wherein the base station, And a second information corresponding to the result of the check is set to the next bit of the most significant bit of the FMT field of the traffic indication message. The method of claim 10, wherein the mobile terminal, The presence of data to be transmitted from the base station is checked by checking the most significant bit of the FMT field, and the next bit of the most significant bit of the FMT field is checked to determine whether the traffic indication information is based on a traffic indication bitmap and sleep of the mobile terminal. Sleep mode operating system, characterized in that identifying whether the identifier based. The method of claim 10, wherein the mobile terminal, If there is data to be transmitted from the base station, the operation mode is shifted to the awake mode, if there is no data to be transmitted from the base station sleep mode characterized in that after calculating the sleep interval and transitions to the sleep mode Operating system.

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