KR20020053446A - Method for management and duplexing of multi overhead channel - Google Patents

Abstract

The present invention relates to a method of operating a multi-overhead channel that enables the continuous operation of the overhead channel and the service state to the mobile station and to provide call processing service when using a plurality of overhead channels. Induces load balancing by operating a plurality of call channels and access channels, builds a database of currently available overhead channels when using multiple overheads, and subordinates the access channel database to the call channel database among the overhead channels. By monitoring the state of call channel and access channel with one database, if state change occurs for each channel, the appropriate data for each state change is notified to call channel, access channel and mobile station. Induce re-initialization of the head channel And to maintain continuous service conditions.

Description

Method for management and duplexing of multi overhead channel}

The present invention relates to a mobile communication system, and in particular, when operating a plurality of overhead channels, by dynamically operating information on the overhead channel and by checking each overhead state to notify the mobile station of the information when the state transition The present invention relates to a method for managing and redundancy of a multi-overhead channel, which enables a normal overhead channel to be operated and maintains a continuous service state to a mobile station.

In general, a mobile communication system uses a plurality of overhead channels for load balancing as the frequency of use of a call channel and an access channel increases. When using a plurality of overhead channels, the overhead channel must be initialized in accordance with the plurality of overhead information, and the mobile station must be informed about the information. In addition, the duplexing scheme for each channel should be changed when operating multiple overhead channels, and when the status of the overhead channel changes, the information of all overhead channels should be reviewed and the changes notified to the mobile station so that the mobile station can maintain continuous service status. I can keep it.

1 is a block diagram illustrating a general mobile communication system.

As shown therein, a mobile station (MS) 10 operating while moving or stopping at a point not specified is received, and a call processing request of the mobile station 10 is received and the call of the control station 30 is received. A base transceiver station (BTS) 20 which transmits a transmission request to the mobile station 10, and a control station (BSC) which controls signal processing between the base station 20 and the exchange 40 ( 30) and a communication network connected with the control station 30 to transmit a call processing request of the mobile station 10 to a public switching telephone network (PSTN) or an advanced mobile phone service (AMPS) through a public network or a dedicated network. It is composed of a switch (MSC, Mobile Switching Center) 40 to be transmitted to the mobile communication service is made.

In the general mobile communication system configured as described above, if the subscriber wants to use the mobile communication service while having the mobile station 10 within the service radius of the switch 40, the switch 40 is connected to the control station 30 to connect the mobile station. The position of 10 is determined, and the mobile station 10 is operated to perform a voice / fax information service or to connect with another communication network according to a request of the mobile station 10 to perform a mobile communication service.

Here, in the PCS (Personal Communication System) and DCS (Digital Communication System) systems, the pilot channel and pilot channel are used to indicate the service state of a mobile station in one sector or cell. In PCS and DCS, the system is determined so that only one channel element is assigned, and the code corresponding to each code is used to make the actual distinction of each channel among 64 code channels. The channel is assigned. The pilot channel is a reference channel for the mobile station 10 to recognize and timing the base station 20. The code channel is assigned with No. 0 and serves as a reference for identifying each sector or cell. The sync channel is assigned with code channel 32 and serves to synchronize initial time synchronization between the mobile station 10 and the base station 20. When the pilot channel and the synchronization channel are assigned one code channel, the base station 20 initializes each channel element and operates the channel and assigns the pilot channel and the synchronization channel to one channel for normal operation. It operates to service each sector and cell.

Up to seven paging channels can be used in one sector or cell, but usually only one channel is used, and code channels can use 1 to 7 codes. The paging channel serves the shape information of the base station 20, the reverse information of the mobile station 10, and the calling role of the mobile station 10.

When the mobile communication system operates one overhead channel, the initialization information of the overhead channel and the overhead information for maintaining the service state of the mobile station are fixed, and for the duplication of the overhead channel, Each could operate with only one overhead channel.

However, when the overhead channel is initialized or the information is operated using only one fixed information when using multiple overhead channels, the changed information may not be accurately reported to the plurality of overhead channels, or the message changed to the overhead channel may not be reported. If the sender does not notify the mobile station of the changed contents, the overhead channel may be abnormally operated. In this case, all mobile stations may not maintain the service state or receive a call processing service.

Accordingly, the present invention is proposed to solve the above problems of the prior art,

An object of the present invention is to build a database of the currently available overhead channel, and to monitor the state of the call channel and the access channel to a single database by subordinate the database of the access channel to the database of the call channel of the overhead channel in one database. In this way, when a state change occurs for each channel, data appropriate to each state can be notified to the mobile station through the calling channel and the access channel, which allows the mobile station to maintain a continuous service state. The present invention provides a method for managing and redundancy of a channel.

The present invention for achieving the above object,

Building an overhead channel database and creating and running BTS Configuration Management (BCM) tasks and state tasks;

Checking whether the state of the overhead channel changes after each task is driven, and if there is a change, searching for an overhead channel duplication related field to determine whether to perform duplication;

Performing a duplication routine of the overhead channel if the duplication is performed as a result of the determination; rearranging the database of the overhead channel if the duplication is not performed;

The method is characterized in that it comprises the step of notifying the mobile station of the change by sending configuration information to the rearranged overhead channel after the database rearrangement.

Reordering the database of overhead channels,

Receiving a state transition from the state task and checking whether the service is available according to the overhead channel type, and if the service is possible, detecting the number of call channels or access channels;

A second step of checking an ID and a Walsh code of a call channel where a state transition occurs after detecting the number of call channels;

Changing the calling channel after the checking and transmitting reconfiguration information to the mobile station through the changed calling channel;

And if a change request is made to the call channel after detecting the number of the access channels, a fourth step of initializing the access channel, changing the call channel, and transmitting reconfiguration information to the mobile station through the changed call channel. .

1 is a block diagram of a general mobile communication system,

2 is a flowchart illustrating an overhead channel database sorting and redundancy process according to the present invention;

FIG. 3 is a flowchart of a duplexing subroutine illustrating a process of performing a duplication routine of the overhead channel of FIG. 2.

<Explanation of symbols for the main parts of the drawings>

10 ..... Mobile Station (MS)

20 ..... Base Transceiver Station (BTS)

30 ..... Base Station Controller (BSC)

40 ..... Mobile Switching Center (MSC)

Hereinafter, a preferred embodiment of a method for managing and duplexing a multi-overhead channel of the present invention according to the above technical concept will be described in detail with reference to the accompanying drawings.

2 is a flowchart illustrating an overhead channel database sorting and duplication process according to the present invention.

As shown therein, an overhead channel database is established in step ST11, and a BCM (BTS Configuration Management) task (TASK) and state task are generated and driven in step ST12.

Next, in step ST13, if there is a state change in the overhead channel, and as a result, if there is no state change, in step ST14, the state task periodically monitors the state of the overhead channel; In ST15, a field related to performing overhead channel redundancy is searched.

After the retrieval, in step ST16, it is determined whether the duplication is performed. If the duplication is performed, the process proceeds to step ST17 to perform the duplication routine of the overhead channel. If the determination is not performed, the duplication of the database on the overhead channel is performed in step ST18. In step ST20, the mobile station sends configuration information to the overhead channel to notify the mobile station of the change.

An overhead channel database sorting and redundancy process having such a configuration will be described in detail as follows.

First, each channel of the base station is divided into pilot, synchronization, access, call, and call channels according to the function. The call channel is obtained by the mobile station after acquiring the pilot signal and the synchronization signal, and then the system information and access information required for system access. It informs PN (Pseudo Noise) information of the frequencies currently served by base stations and neighboring base stations.

The call channel can be extended up to 7 and Walsh code is used from 1 to 7 times. In addition, each access channel is subordinated to the call channel, and when the base station intends to service a plurality of overhead channels, the access channel has information related to the call channel and the access channel. This is used to database the contents of the call channel per frequency / per sector / per call channel and subordinate the access channel to the database of the call channel.

The database configuration of the call channel is defined as follows.

Pch_Db [Max_Cdma_Ch_Idx_Per_BTS] [Max_Sector_Per_BTS] [Max_Pch_Per_Subcell]

Here, "Max_Cdma_Ch_Idx_Per_BTS" is the maximum number of frequencies that the base station can service, "Max_Sector_Per_BTS" is the number of sectors that the base station can service, Max_Pch_Per_Subcell is the number of available call channels per frequency / per sector, and Max_Ach_Per_Pch is the access channel per calling channel. It means the number of each.

In addition, the access channel database configuration is defined as follows.

Ach_Db [Max_Cdma_Ch_Idx_Per_BTS] [Max_Sector_Per_BTS] [Max_Pch_Per_Subcell] [Max_Ach_Per_Pch]

Next, after acquiring the pilot signal and the synchronization signal of the base station, the mobile station receives overhead information (System Parameter Message, Access Parameter Message, etc.) from the call channel of the base station in order to transition to the idle state. The contents of the "PAGE_CHAN" field of the System Parameter Message are retrieved to select the call channel that the mobile station should receive.

The base station generates a BTS (BTS Configuration Management) task for initializing and configuring an overhead channel and a state task for monitoring a state change of an overhead channel, and the BCM task is configured to initialize and execute an overhead channel. Send information related to the base station to the mobile station. The state task periodically checks the state of the overhead channel or updates the state of the state in the overhead channel database when the state of the overhead channel changes through real-time state information of the overhead channel.

When the base station adds an overhead channel by the user's command, the overhead channel of "N_EQUIP-M_BLK" is shifted to the "EQUIP-M_UBLK" state, and the BCM task initializes the overhead channel and overheads the changed state. It updates the channel database and informs the mobile station of the changed channel information by referring to the contents of the database so that the mobile station can refer to the changed overhead information. Status tasks also monitor the state of the added overhead by referencing the updated content. In addition, even if the overhead channel is not the primary call channel, the above overhead realignment operation is required.

In the event of an abnormality of the primary (calling channel assigned to Walsh code 0) of a plurality of overhead channels, the mobile station should refer to the primary calling channel in order to transition from the transitioned state to the idle state. Therefore, when an abnormal primary call channel occurs, another call channel must be changed to the primary call channel.

The status task updates the overhead database contents when the status of the overhead channel transitions, and informs the BCM task of the frequency, sector, and channel type. The BCM task has information related to whether to perform the overhead duplication set by the operator. Refer to to determine whether to perform overhead duplication. Here, the duplication of the overhead channel uses an idle call channel, and if there is no idle call channel, the call channel being used is replaced by an overhead channel, and the change is notified to the mobile station.

3 is a flowchart of a subroutine showing another overhead channel database reordering process in FIG.

As shown in FIG. 2, the rearrangement of the overhead channel database in step ST18 of FIG. 2 is followed by checking the overhead channel type in step ST32 after receiving a state transition from the state task in step ST31 of FIG. As a result, in the case of a call channel (PCH), the state of the call channel is checked in step ST33 (the number of available call channels per frequency stage / sector), and in the case of the access channel (ACH), the state of the access channel in step ST34. Is checked (the number of low-speed channels per calling channel), and the flow proceeds to step ST35.

Next, after checking the state of the call and access channel from step ST33 and step ST34, it is determined in step ST36 whether or not the service of each channel. If the resultant service is not available, the process returns to step ST33 and step ST34, respectively, and the state check is performed again. If the determination result service is possible, the process proceeds to step ST36 for the call channel, and if it is an access channel, proceeds to step ST42. do.

First, the number of call channels Num_of_PC currently available in step ST36 is detected, and the ID (PCH_ID) and Walsh code of the call channel where the state transition occurs in step ST37 are checked.

In step ST38 after the checking, it is determined whether the call channel is a primary call channel (call channel assigned with Walsh code 0), and as a result, if the call channel is not a primary call channel, the state transitions from the last call channel in step ST39. Is replaced with the call channel that occurred, and when the determination result is the primary call channel, the last call channel is changed to the primary call channel in step ST40 and then reconfigured to the call channel in step ST41.

Next, if service is available after the state of the access channel is checked in step ST36, the number of available access channels Num_of_AC under the current call channel is detected in step ST42, and it is determined whether to change to the call channel in step ST43, As a result, if there is a change to the call channel, the access channel is initialized in step ST44, and then in step ST45, the access channel is changed to the call channel and reconfigured in step ST46.

The subroutine operation of database reordering of an overhead channel having such a configuration will be described as follows.

First, the BCM task performs an overhead database reordering operation according to the overhead channel type. In case of call channel, check all call channels under the frequency and sector and update the number of call channels that can be serviced in the "Num_of_PC" field in call channel database. Check the subordinate access channel dependent on the calling channel and update it to "Num_of_AC" (number of available access channels under the current calling channel) in the calling channel database.

In addition, when the overhead channel in which the state transition occurs is the primary call channel, the BCM task transmits configuration information to the corresponding call channel so that the call channel corresponding to the end of Num_of_PC is replaced with the primary call channel. To work. After receiving notification of normal service availability from the call channel, overhead information (System Parameter Message) is transmitted to the call channel to notify the mobile station of the change of the base station to all call channels capable of normal service of the corresponding frequency and sector. .

In addition, if the call channel having the state transition is the call channel of the intermediate point, as described above, by replacing the call channel with the state transition to the last call channel, it is possible to prevent the reconstruction of all the call channels when an error occurs in one call channel. do.

In addition, when an error occurs in the call channel, the corresponding access channel cannot be used. Therefore, the access channel is initialized so that the subordinate access channel of the call channel in which the state transition has occurred can be changed to the call channel, and the overhead information (Access Parameter Message) is transmitted to the mobile station. By transmitting a notification of the change of the base station, the operator can change the access channel to a communication channel to use.

According to the above-described "method of managing and duplexing the multi-overhead channel", when operating a plurality of overhead channels, the information about the overhead channel is dynamically operated and the state transitions by checking the respective overhead states. By notifying the signal to the mobile station, it is possible to operate the overhead channel normally, and has the advantage of maintaining a continuous service state between the mobile station and the base station.

In addition, by notifying the mobile station of accurate information on the overhead channel, it has the advantage of distributing the overhead channel load and providing a good call service to the mobile station.

Claims (6)

In the overhead channel operation and duplication method in a mobile communication system, Building an overhead channel database and creating and running BTS Configuration Management (BCM) tasks and state tasks; Checking whether the state of the overhead channel changes after each task is driven, and if there is a change, searching for an overhead channel duplication related field to determine whether to perform duplication; Performing a duplication routine of the overhead channel if the duplication is performed as a result of the determination, and realigning the database of the overhead channel if the duplication is not performed; And notifying the mobile station of the changed information by transmitting configuration information on the rearranged overhead channel after the database rearrangement. The method of claim 1, wherein reordering the database of overhead channels comprises: Receiving a state transition from the state task, checking whether the service is available according to the overhead channel type, and if the service is possible, detecting the number of call channels or access channels; A second step of checking an ID and a Walsh code of a call channel in which a state transition has occurred after detecting the number of call channels; Changing the calling channel after the checking and transmitting reconfiguration information to the mobile station via the changed calling channel; And if a change is requested to the call channel after detecting the number of the access channels, a fourth step of initializing the access channel, changing to the call channel, and transmitting reconfiguration information to the mobile station through the changed call channel. Multi-overhead channel management and redundancy The method of claim 1, wherein the performing of the redundancy routine comprises: Searching for the presence of an idle call channel; if there is an idle call channel as a result of the search; replacing the idle call channel with an overhead channel; and if there is no idle call channel, the call currently being used. Replacing the channel with an overhead channel and notifying the mobile station of the channel change. The method of claim 2, wherein in the overhead channel type check, If the check result is a call channel, the state of all call channels under the frequency and sector is checked and the number of call channels that can be serviced is updated in the "Num_of_PC" field of the call channel database. And checking the subordinate access channel dependent on the channel and updating the subordinate access channel to "Num_of_AC" of the calling channel database. The method of claim 2, wherein the third step, Checking whether the overhead channel is the primary call channel, and if the result is a primary call channel, managing and redundancy of the multi-overhead channel after changing the last call channel to the primary call channel and transmitting call channel reconfiguration information Way. 5. The method of claim 4, wherein if the overhead channel is not the primary call channel as a result of the checking, the last call channel is changed to a call channel where a state transition occurs.