KR20060096210A - Method for notificating deregistration of mobile terminal in wideband radio access system - Google Patents

Abstract

In the broadband wireless access system, when a mobile station is normally or abnormally deregistered from a service base station, the deregistration notification of the mobile station in which the service base station informs neighboring base stations of deregistration of the mobile station by using a backbone message is provided. Provide a method. Preferably, the deregistration of the mobile terminal is delivered through a backbone message indicating the deregistration of the mobile terminal or a backbone message indicating the registration information of the mobile terminal.

Deregistration, Backbone Message, Broadband Wireless Access System

Description

Notification of deregistration of terminal in broadband wireless access system {METHOD FOR NOTIFICATING DEREGISTRATION OF MOBILE TERMINAL IN WIDEBAND RADIO ACCESS SYSTEM}

1 is a detailed block diagram of a conventional I-am-host-of message.

2 is a detailed block diagram of a conventional MSS-info-request message.

3 is a detailed block diagram of a conventional MSS-info-response message.

4 is a detailed block diagram of a conventional BS-info-request message.

5 is a detailed configuration diagram of a conventional BS-info-response message.

6 is a detailed block diagram of a conventional HO-pre-notification message.

7 is a detailed block diagram of a conventional HO-pre-notification-response message.

8 is a detailed configuration diagram of a conventional HO-confirm message.

9 is a diagram illustrating a transfer procedure of a backbone message for sharing state information of a conventional terminal and a base station.

10 is a diagram illustrating a handover and a delivery procedure of a backbone message by a request of a conventional terminal.

11 is a diagram illustrating a method for notifying registration release of a terminal according to an embodiment of the present invention when the terminal is normally deregistered in the present invention.

12 is a diagram illustrating a method for notifying registration deregistration according to an embodiment of the present invention when a terminal is abnormally deregistered in the present invention.

FIG. 13 is a view showing an example of a backbone message used for notification of deregistration of a terminal when the terminal is normally or abnormally deregistered in the present invention. FIG.

14 is a view showing an example of a backbone message for notifying registration information of a mobile terminal, used for notification of deregistration of a terminal in the present invention.

The present invention relates to a broadband wireless access system, and more particularly, to a method for notifying a neighbor base station of deregistration of a mobile terminal.

In general, backbone network services between base stations in a broadband wireless access system are a backbone message for sharing state information of a terminal, a backbone message for sharing state information of a base station, and a backbone message for handover. It is composed.

Among the backbone messages, a backbone message for sharing status information of the terminal is composed of an I-am-host-of message, an MSS-info-request message, and an MSS-info-response message. The I-am-host-of message is transmitted from the serving base station of the terminal to the neighboring base station when the terminal is registered in the service base station, the handover is completed, or periodically, the detailed configuration is shown in FIG.

The MSS-info-request message is a message sent when requesting information of a specific terminal from one base station to another base station. In particular, the message is a message for requesting the service base station of the terminal when receiving an I-am-host-of message or when a specific terminal enters its network after the handover. A detailed configuration is shown in FIG. 2. Finally, the MSS-info-response message is a message that informs the base station requesting the MSS-info-request message the information on the corresponding terminal, the detailed configuration of which is shown in FIG.

Next, the backbone message for sharing the status information of the base station is composed of a BS-info-request message and a BS-info-response message. The BS-info-request message is a message for requesting information of each base station from one base station to an adjacent base station, and is broadcast when the ID of the target base station is 0xFFFFFF. The configuration of the BS-info-request message is shown in FIG. 4. In addition, the BS-info-response message is broadcasted to a neighboring base station when there is a request for a BS-info-request message from another base station or when channel information of the base station is changed, and the detailed configuration thereof is shown in FIG. 5. .

Finally, the backbone message required for the handover consists of a HO-pre-notification message, a HO-pre-notification-response message, and a HO-confirm message.

The HO-pre-notification message is a message transmitted from the terminal or the base station to the handover to the target base station, and the terminal requesting the handover asks whether the service received from the service base station is supported by the target base station. In this case, the HO-pre-notification message includes the contents as shown in FIG. 6. And, as shown in Figure 7, the HO-pre-notification-response message is a message to send the base station requested by the base station received the HO-pre-notification message, which is supported when the terminal is handed over to the base station Contains information about the service. In addition, the HO-confirm message is a message sent from the serving base station to the target base station, as shown in FIG. 8, and is a message for notifying that a handover occurs after a predetermined time (notified by the HO-pre-notification message). .

The following describes the network registration procedure of a terminal in a broadband wireless access system.

1, network registration procedures

When the first power is turned on, the terminal searches for a downlink channel and acquires up / down synchronization with the base station. The terminal performs ranging with the base station to adjust the uplink transmission parameter and receives a basic management connection identifier (Basic management CID) and a first management connection identifier (Primary management CID) from the base station.

In addition, the terminal negotiates basic performance with the base station, and the base station authenticates the terminal. Subsequently, the terminal registers with the base station, and the terminal managed by IP receives the second management connection identifier (Secondary management CID) from the base station to set the IP connection, the current date and time. In addition, the terminal downloads the configuration file of the terminal from the TFTP server, and establishes a connection to a service prepared in advance.

As described above, when the initial network registration procedure is performed, the terminal switches to a normal operation state so that data can be transmitted and received through the uplink and downlink wireless links with the base station. Then, when data to be transmitted to the base station is generated, the terminal transmits data to the base station by receiving an uplink slot from the base station through a band request. In addition, the terminal periodically performs a ranging procedure for adjusting uplink transmission parameters in order to continuously maintain uplink communication with the base station.

2. Periodic ranging

Ranging consists of initial ranging and periodic ranging. Initial ranging refers to a procedure of acquiring an appropriate transmission parameter value such as a time offset, a frequency offset, and a transmission power level for uplink communication with a base station in a network registration process of the terminal. When the initial ranging is completed, the terminal performs periodic ranging in order to continuously maintain uplink communication with the base station. Periodic ranging is performed in all physical layers in a broadband wireless access system. In a single carrier and OFDM scheme, periodic ranging is performed through the following procedure.

First, the base station maintains a timer called T27 for each terminal. Once the timer expires, the base station allocates an uplink slot to the terminal to perform ranging.

The terminal maintains a T4 timer. When the terminal does not allocate an uplink slot for data transmission from the base station until the timer expires, the terminal determines that the uplink transmission parameter is invalid and initializes and restarts the MAC. The base station allocates an uplink slot for periodic ranging of the terminal and measures an uplink signal from the terminal. If the allocation request message is not received from the terminal even though a predetermined number of uplink slots for ranging are allocated, the base station terminates connection management with the terminal.

In addition, the base station measures the uplink signal quality received from the terminal. The base station receives the uplink signal including the ranging request message from the terminal, and informs that the ranging is successful through the ranging response message when the signal quality is within the appropriate line. If the signal quality does not fall within the proper line, the ranging response message indicates that the ranging should be continued along with the parameter correction value. If the signal quality does not enter the proper line until the predetermined number of corrections is exceeded, the base station transmits to the terminal to stop ranging through a ranging response message, and terminates the connection management with the terminal.

Therefore, after receiving the ranging response message, the terminal corrects the uplink transmission parameter value and determines whether to terminate the ranging, continue, or initialize and restart the MAC.

3. Deregistration of terminal

The deregistration of the terminal includes normal deregistration and abnormal deregistration. In normal deregistration, when a terminal sends a deregistration request (DREG-REQ) message to the base station and requests deregistration of the normal operation service for the terminal, the base station transmits a DREG-CMD on the base CID of the terminal. De-registering the connection state of the corresponding terminal by sending a message. On the other hand, the abnormal deregistration, in the periodic ranging process, when the base station has not received the uplink signal from the terminal until a predetermined number of times to deliver to the terminal to stop the ranging through a ranging response message and , Ending the connection management with the terminal.

Meanwhile, in a broadband wireless access system, a procedure of transmitting a backbone message between base stations is configured as follows.

FIG. 9 is a diagram illustrating a transfer procedure of a backbone message for sharing state information of a terminal and a base station, and FIG. 10 is a diagram illustrating a transfer procedure of a handover and a backbone message at the request of a terminal. Referring to FIG. 9, it can be seen that information on a terminal registered in each base station and channel information of each base station are shared with a neighboring base station. FIG. 10 illustrates a procedure of forwarding a backbone message with a serving base station when a handover occurs, and registering the terminal with the target base station by terminating the service with the serving base station. However, a procedure for notifying the serving base station that the registration to the neighbor base station of the corresponding terminal is released by the backbone message is not defined.

Conventionally, in a broadband wireless access system, when a mobile station is deregistered from a serving base station, a procedure for informing the neighboring base stations of the serving base station is not defined. Therefore, there is an unreasonable point that neighboring base stations must keep the information of the mobile station deregistered from the serving base station. In addition, when the mobile station requests initial ranging, it is impossible to accurately distinguish whether it requests an initial ranging for initial registration in the network or an initial ranging during the association. Problems arise.

Accordingly, an object of the present invention is to provide a method in which a serving base station can inform neighboring base stations of deregistration of a mobile station when the mobile station is deregistered from the serving base station.

In order to achieve the above object, when the mobile station is deregistered from the service base station in the broadband wireless access system, the service base station informs neighbor base stations of the deregistration of the mobile station using a backbone message.

Preferably, the deregistration of the mobile terminal includes both normal release upon request of the terminal and abnormal deregistration due to ranging reception failure.

Preferably, the deregistration of the mobile terminal is delivered through a backbone message indicating the deregistration of the mobile terminal or a backbone message indicating the registration information of the mobile terminal. In this case, the backbone message indicating the registration information of the mobile terminal is an I-am-host-of message.

Hereinafter, preferred embodiments of the present invention will be described in detail.

The present invention is implemented in a broadband wireless access system. However, the present invention can also be applied to a wireless communication system operating according to other standards. Hereinafter, preferred embodiments of the present invention will be described in detail.

The present invention proposes a backbone message and a procedure for delivering a message to a neighboring base station, indicating that the serving base station is deregistered to a neighboring base station when the mobile station is deregistered from the base station in the broadband wireless access system.

In the broadband wireless access system according to the present invention, a method for notifying registration of a terminal is divided into a case of normal deregistration and abnormal deregistration.

11 is a diagram illustrating a method for notifying registration release of a terminal according to an embodiment of the present invention when the terminal is normally deregistered.

Referring to FIG. 11, the mobile station MSS1 transmits a deregistration request (DREG-REQ) message to the service base station BS # 1 while communicating with the service base station BS # 1. (BS # 1) transmits a deregistration command (DREG-CMD) to the mobile terminal so that the MSS # 1 is normally deregistered from the service base station BS # 1.

Once the mobile terminal MSS # 1 is normally deregistered from the serving base station BS # 1, the serving base station BS # 1 deregisters the mobile station MSS # 1 to the neighboring base station using a backbone message. It tells you that

12 is a diagram illustrating a method for notifying registration deregistration according to an embodiment of the present invention when a terminal is abnormally deregistered.

In general, when the ranging request is not received from the idle mode terminal within a predetermined time, the base station deletes the terminal from the list of valid idle mode terminals and deregisters the terminal. At the same time, the base station uses the backbone message to inform the base stations belonging to the same paging group that the terminal is abnormally registered.

Referring to FIG. 12, when the serving base station BS # 1 does not receive the ranging request from the idle mode terminal within a predetermined time period, the serving base station BS # 1 transmits a ranging response (RNG-RSP) message to the MSS # 1. At the same time, the mobile station MSS # 1 is deregistered to neighbor BSs BS # 2 and BS # 3 using a backbone message.

Preferably, the present invention uses a terminal deregistration (MSS-DREG) message shown in FIG. 13 as a backbone message indicating the deregistration of the mobile terminal, and the MAC address of the mobile terminal (MSS # 1) is used for the MSS-DREG message. And corresponding service base station information.

In addition, the present invention is not limited to the backbone message for notifying the deregistration, and may also be informed by inserting deregistration information into a backbone message for notifying registration information of the mobile terminal.

That is, as shown in Figure 14, the neighboring base station by inserting the deregistration information into the backbone message, that is, the I-am-host-of message to inform the registration information of the mobile station MSS # 1 of the service base station (BS # 1) (BS # 2, BS # 3).

As described above, in the related art, when a mobile station is deregistered from a serving base station, a procedure for informing the neighboring base stations of the serving base station is not defined. Therefore, there is an unreasonable point that neighboring base stations must maintain information of the mobile station deregistered from the serving base station.

Therefore, after the service base station deregisters a specific mobile station, the neighboring base stations are informed of the deregistration of the mobile station so that the neighboring base stations can immediately release the information of the mobile station. In addition, when the mobile station requests initial ranging by allowing the base stations to update the state of the mobile station, whether the mobile station requests initial ranging for initial registration in the network or initial ranging in the process of performing association. By clarifying the distinction of whether to request a, it is possible to efficiently perform the normal operation service of the mobile terminal.

In addition, although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary and will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (6)

In a broadband wireless access system And when the mobile station deregisters from the service base station, the service base station notifies neighboring base stations of deregistration of the mobile station by using a backbone message. The method of claim 1, wherein deregistration of the mobile terminal is performed. Method for deregistration registration of a terminal, characterized in that it includes both normal release by the request of the terminal and abnormal deregistration due to ranging reception failure. The method of claim 1, wherein the backbone message is Deregistration notification method of a terminal, characterized in that the message indicating the deregistration of the mobile terminal. 4. The method of claim 3, wherein the backbone message is Method for deregistration of a terminal, characterized in that the terminal deregistration (MSS-DREG) message. The method of claim 1, wherein the backbone message is A method for notifying registration release of a terminal, characterized in that a message for notifying registration information of a mobile terminal. 4. The method of claim 3, wherein the backbone message is Method for notifying registration release of a terminal, characterized in that the I-am-host-of message.

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