KR20050065026A - Apparatus and method of call admission control based on guard channel - Google Patents

Abstract

The present invention relates to a guard channel-based lake lock control apparatus and method.

According to the present invention, when the available channel for the new call is insufficient for the call request, if the corresponding call is a non-real-time service call, the guard channel is allocated to provide a service by providing the service, and then the hand requesting the call. If there is a lack of guard channels when there is an off call, a dedicated channel is reconfigured to a common channel for a call currently using a non-real-time service so that an available channel can be secured for a handoff call.

According to the present invention, it is possible to reduce the inefficient use of resources according to the guard channel, to provide a service without disconnection of the handoff call while increasing the resource utilization efficiency.

Description

Apparatus and method of call admission control based on guard channel}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guard channel based rockacy control method, and more particularly, to perform rockaclock control based on a guard channel in a wideband code division multiple access (WCDMA) system. The present invention relates to a guard channel-based rock lock control apparatus and method.

In a mobile communication system, since radio resources and resources of a base station are limited, users who can accommodate them at the same time are limited. In particular, since the limitation of the wireless section capacity in the mobile communication system is large, it is determined whether to accept or reject the service request of the subscriber based on the wireless capacity.

In addition, in the CDMA system, since the subscriber's radio signal interferes with other subscribers, the quality of service of the existing subscriber is degraded when the subscriber receives more subscribers than the subscriber can accommodate. Therefore, a call admission control method that can accept as many subscriber calls as possible while ensuring the quality of service (QoS) of existing subscribers has been studied.

1 is a cell configuration diagram of a wideband code division multiple access (W-CDMA) system.

Referring to FIG. 1, a W-CDMA system for performing wireless channel communication with terminals 110 to 130 includes a base station 210 and 220 and is connected to a core network 230 to provide a broadband service. .

The base station (210, 220) forms a wireless channel with the terminal (110 ~ 130) to perform the access point to enable the voice call or data transmission and reception, and the appropriate call for the lock request of the terminal (110 ~ 130) Perform admission control.

The general call admission control method predicts the amount of interference caused by accepting a call when a call requesting acceptance is received, and if the amount of interference is lower than an allowable level, the call is accepted. Reject call.

An important point in general call admission control is that handoff calls must be serviced before new calls. This is because, from the user's point of view, it is more uncomfortable when the call is disconnected during the call than when the call fails.

Therefore, a number of proposals have been proposed for preventing handoff calls in call admission control. Guard Channel Scheme is a representative one of these methods, which designates a portion of the base station's total channel capacity as a guard channel, and when a guard channel remains, only a handoff call is accepted without a new call. to be.

2 is a conceptual diagram of rock lock control in conventional W-CDMA.

Referring to FIG. 2, only the call admission control unit 201 and the channel state measurement unit 202 of the base station 210 and 220 are conceptually represented, and the rock lock control unit 201 is a new call or hand from the terminals 110 to 130. Receiving an off-call request, performing the lock control operation, the channel state measuring unit 202 measures the capacity of all the channels of the base station 210, the guard channel, the available channel and the use channel by the lock lock control unit 201 Inform)

If the available channel is larger than the guard channel, the lock control unit 201 accepts the call for all calls. If the available channel is smaller than or equal to the guard channel, the lock control unit 201 only locks the handoff call.

However, although this guard channel method is advantageous to prevent the disconnection of handoff calls, resource utilization efficiency is lowered because the new channel cannot be accepted by reserving resources even if an actual handoff call does not occur.

In other words, the guard channel technique is a reliable method of preventing the disconnection of handoff calls, but if the handoff does not occur, the resources reserved for the guard channel are not available and are wasted in the end, thus reducing resource utilization efficiency.

If the guard channel capacity is set too large, the disconnection of the handoff call can be prevented, but the resource utilization efficiency is reduced by that much. If the guard channel capacity is set too small, the resource utilization efficiency can be increased, but the handoff call may be disconnected. Therefore, much research has been conducted on how much the capacity of the guard channel should be.

Such research has been conducted by providing a basis for setting the capacity of the guard channel or by dynamically changing the guard channel capacity according to the situation. In other words, the call admission control method to prevent the disconnection of the handoff call and the resource utilization efficiency has been studied, but the method of satisfying both has not been proposed yet.

In order to solve the above problems, an object of the present invention is to provide a guard channel-based call admission control apparatus and method for preventing the disconnection of the handoff call and increase the resource utilization efficiency in the guard channel-based call admission control method. It is done.

Guard channel-based rockacy control device according to one feature of the present invention,

An apparatus for controlling rock lock of a base station of a wireless communication system performing wireless communication with a terminal, the apparatus comprising: receiving a request for a new call or a handoff call from the terminal, and determining whether the lock is based on a current channel state of the base station; Lokrak control unit for determining; A channel state measuring unit for measuring channel information including the channel capacity of the entire base station, a guard channel for a handoff call, an available channel that can be used, and a channel being used, and providing the channel information to the lake lock controller; And a guard channel call information storage unit for storing the information on the corresponding call when the lock access control unit performs the lock access using the guard channel for the new call.

Guard channel-based rock lock control method according to an aspect of the present invention,

A method for controlling a rock lock at a base station of a wireless communication system performing wireless communication with a terminal, the method comprising: (a) the base station receiving a new call acceptance request from the terminal, checking a current channel state, and Determining whether the channel capacity required for acceptance is less than or equal to the remaining available channel; (b) determining that the new call requesting the lake lock is a non-real-time service when the channel capacity required for the new lake lock is larger than an available channel; And (c) if the new call is for a non-real-time service, accepting the call using a guard channel for a handoff call.

And i) receiving, by the base station, a handoff call accept request from the terminal and checking a current channel state to determine whether the channel capacity required for accepting the handoff request call is larger than the currently available available channel. ; ii) determining whether the guard channel for the handoff call request is larger than the channel capacity required for the rock lock if the channel capacity required for the rock lock is larger than the available channel; iii) As a result of the determination, if the guard channel is smaller than the channel capacity required for the rock lock, and there is a non-real-time service call using the current guard channel, the non-real-time service call is changed from a dedicated channel to a common channel to secure an available channel. Checking whether the secured available channel is greater than or equal to the channel capacity for the lake lock; And iv) accepting the handoff call request if the reserved available channel is greater than or equal to the channel capacity for the rock lock.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the accompanying drawings, parts irrelevant to the description of the present invention are omitted in order to clearly describe the present invention, and the same or similar parts are denoted by the same reference numerals.

In the mobile communication system, since the capacity of the wireless section is not limited, it is important to make the best use of the resources of the wireless section. In addition, resource reservation is required to accommodate handoff calls to prevent disconnection of existing services.

These two objectives in call admission control are in conflict with each other and there are many difficulties in satisfying both.

Therefore, in the present invention, by reducing the size of the guard channel capacity according to the situation, or by using a method of allocating a new call to the guard channel according to the situation to reduce the waste of resources according to the guard channel while receiving a handoff call An apparatus and method are presented.

3 is a conceptual diagram of a guard channel-based rock lock control apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the base station includes a rock lock control unit 310, a channel state measurement unit 320, and a guard channel call information storage unit 330 for rock lock control.

The lock control unit 310 receives a new call or a handoff call request, performs the lock control, and the channel state measuring unit 320 measures the total channel capacity, guard channel, and available channel state of the base station and locks the lock. The control unit 310 informs.

The guard channel call information storage unit 330 stores information of a new call allocated to the guard channel.

The guard channel call information storage unit 330 allocates a new call to the guard channel and locks it. When the handoff call request comes in, there is no available channel for accepting the handoff call. Information about the call of the non-real-time service that has been allocated is provided to the lakrak control unit 310.

The lock control unit 310 enables the non-real-time service calls to be changed from a dedicated channel to a common channel using the non-real-time service call information received from the guard channel call information storage unit 330.

Calls that are switched from a dedicated channel to a common channel receive low data services, but this process results in an available channel, which allows for a lockoff on a handoff call with a locklock request.

4 is a flowchart illustrating an operation of a guard channel-based rock lock control method according to an exemplary embodiment of the present invention.

Referring to FIG. 4, a terminal 410 that moves while performing wireless communication with a base station and requests a handoff call to the base station 430, and a base station for a non-real-time data service in a communication area of the base station 430. It shows a message flow according to the rock lock control between the terminal 420 and the base station 430 performing communication by receiving the guard channel from 430.

When the terminal 410 moves out of the communication area of the base station 430 and requests a handoff to the base station 430 (S401), the rock lock control unit 310 of the base station 430 is available for allocation to the handoff call. It is determined whether the channel is sufficient (S402), and if the available channel is not sufficient, a channel reconfiguration message (Channel Reconfiguration) is requested to change the channel to a common channel to the terminal 420 using the non-real-time service (S43). ).

Upon receiving the channel reconfiguration message, the terminal 420 reconfigures the current service channel from the dedicated channel to the common channel and transmits a response message (Channel Reconfiguration ack) to the base station 430 (S404).

After the base station 430 reconfigures the non-real-time service channel in the common channel in the dedicated channel, the base station 430 checks again whether the available channel is sufficient to accept the handoff call (S405), and the terminal 420 makes the channel. If the available channel is not sufficient even after the change, the terminal 420 receiving another non-real time service is requested to reconfigure the channel to secure the available channel.

When the available channel is sufficient, a handoff allow message is transmitted to the terminal 410 (S406), and the terminal 410 transmits a handoff complete message to the base station 430 after handoff. The handoff is completed (S407).

Through the above process, the guard channel is allocated to a call request from the terminal 420 for using the non-real-time service, and when there is a handoff call request, the terminal 420 using the non-real-time service to secure an available channel. By reconfiguring the channel from the dedicated channel to the common channel, the lock channel can be efficiently controlled by using the guard channel and the service for the handoff call can be provided.

At this time, if the same process as the steps S403 to S405, there is a problem that it may take a lot of time to check the channel state and transmit and receive the channel reconfiguration message to secure the available channel.

Therefore, in order to solve this problem, call information to be reconfigured for each channel can be obtained at once and reconstruction of several channels can be performed simultaneously.

At this time, the list of arcs to be reconstructed can be obtained as follows.

At this time, Is the capacity of the channel needed to accept a handoff call, Is the available channel capacity that can be obtained when i-th call is converted from dedicated channel to shared channel.

As shown in Equation 1 above, a channel list to be reconfigured is obtained. If the available channel is sufficient by reconfiguring the channel, a handoff call can be accepted.

FIG. 5 is a detailed flowchart of an operation when the gain of an available channel is unknown in FIG. 4 according to an embodiment of the present invention.

Referring to FIG. 5, when the base station 430 receives a lock request in FIG. 4 (S502), it is determined whether the requested call is a new call or a handoff call (S503). At this time, the channel capacity required to accept the call request is It is defined as

For new calls, channel capacity (AC-GC), minus Guard Channel (GC) minus Available Channels (AC), is required It is determined whether it is larger (S510).

As a result of the determination in step S510, 'AC-GC' If greater than the corresponding call is accepted (S509).

However, the determination result of step S510, the 'AC-GC' If less than or equal to, the available channel It is determined whether it is larger (S511), the available channel (AC) If less than the call rejected (S512), the available channel (AC) is If greater, it is determined whether the corresponding call is for using a non-real-time service (S513).

If the new call requesting the call is for the non-real-time service, the non-real-time call list is updated (S514), and the guard channel (GC) is assigned to the call to accept the call (S514). However, if the call is not for a non-real-time service, the call is rejected (S512).

In addition, as a result of the determination in step S503, if the call requesting the rock lock is a handoff call, the guard channel GC Check whether it is larger (S504), the guard channel (GC) is If greater than, accept the call (S509).

However, the guard channel (GC) If less than or equal to, the channel of the non-real-time call is reconfigured (S505), the non-real-time list is updated (S506), and the available channel (AC) is It is determined whether it is larger (S507).

As a result of the determination in step S507, the available channel AC If greater than, accept the call (S509), the available channel (AC) If less than or equal to 1, increase i by 1 to reconstruct another non real time call channel (S505), update the non real time call list (S506), and make available channel (AC) Repeat until it is bigger.

In this case, the processes of steps S505 to S508 reconstruct each non-real-time call in turn because the base station 430 does not know the gain that an available channel can obtain when the base station 430 reconfigures the dedicated channel used by the non-real-time call to a common channel. And available channels The process of checking whether it is greater is repeated.

However, when the dedicated channel is reconfigured to the common channel and the gain obtained by the available channel can be known, the operation is slightly different as follows.

FIG. 6 is a detailed flowchart illustrating an operation when the gain of an available channel is known in FIG. 4 according to an embodiment of the present invention. FIG.

Referring to FIG. 6, the rock lock control operation for the new call is omitted as it operates as in FIG. 5.

In case of a request for a handoff call, the guard channel (GC) If less than or equal to, a list for channel reconstruction is obtained by using Equation 1 (S605).

After reconstructing the channels according to the list and updating the non-real-time call list (S607), the available channel (AC) It is determined whether it is larger (S607), the available channel (AC) is If greater than, accept the call (S609), the available channel (AC) is If less than or equal to the call is rejected (S608).

As described above, the non-real-time call is accepted using the guard channel, and the non-real-time call is reconfigured to the common channel for the handoff call so that the lock can be performed. have.

Although a preferred embodiment of the present invention has been described in detail above, the present invention is not limited thereto, and various other changes and modifications are possible.

As described above, the guard channel-based lake lock control apparatus and method according to the present invention further increases the lock lock capacity by allocating up to the guard channel when the new call requesting the lake lock is a call for using a non-real-time service, and handoff. For the call, the call using the non-real-time service is reconfigured from the dedicated channel to the common channel to secure the available channel, and then use the radio resources efficiently by allowing the user to freely access the handoff call. There is.

1 is a cell configuration diagram of a W-CDMA system.

2 is a conceptual diagram of rock lock control in conventional W-CDMA.

3 is a conceptual diagram of a guard channel-based rock lock control apparatus according to an embodiment of the present invention.

4 is a flowchart illustrating an operation of a guard channel-based rock lock control method according to an exemplary embodiment of the present invention.

FIG. 5 is a detailed flowchart of an operation when an available channel does not know gain in FIG. 4 according to an embodiment of the present invention.

FIG. 6 is a detailed flowchart of an operation when an available channel can know gain in FIG. 4 according to an embodiment of the present invention.

Claims (9)

An apparatus for rock lock control of a base station of a wireless communication system performing wireless communication with a terminal, A lock lock control unit which receives a request for a new call or a handoff call from the terminal and determines whether the lock is in accordance with the current channel state of the base station; A channel state measuring unit for measuring channel information including the channel capacity of the entire base station, a guard channel for a handoff call, an available channel that can be used, and a channel being used, and providing the channel information to the lake lock controller; And Guard channel call information storage unit for storing the information about the call when the lake lock control unit performs the rock lock using the guard channel for a new call Guard channel-based lake lock control device comprising a. The method of claim 1, The lake rack control unit, The guard channel-based lock lock control device for the new call requesting the non-real-time service requested from the terminal, if there is no available channel, performing the lock lock using the guard channel. The method of claim 1, The lake rack control unit, And a control channel for controlling a lock channel based on the non-real-time service call using the non-real-time service call information stored in the guard channel call information storage unit. In the method for controlling the rock in the base station of the wireless communication system for performing a wireless communication with the terminal, (a) receiving, by the base station, a new call acceptance request from the terminal and checking a current channel state to determine whether the channel capacity necessary for accepting the new call is less than or equal to the remaining available channel; (b) determining that the new call requesting the lake lock is a non-real-time service when the channel capacity required for the new lake lock is larger than an available channel; And (c) if the new call is for a non-real-time service, accepting the call using a guard channel for a handoff call. Guard channel-based lake rock control method comprising a. The method of claim 4, wherein In the step (c), i) receiving, by the base station, a handoff call accept request from the terminal and checking a current channel state to determine whether the channel capacity required for accepting the handoff request call is greater than the currently available available channel; ii) determining whether the guard channel for the handoff call request is larger than the channel capacity required for the rock lock if the channel capacity required for the rock lock is larger than the available channel; iii) As a result of the determination, if the guard channel is smaller than the channel capacity required for the rock lock, and there is a non-real-time service call using the current guard channel, the non-real-time service call is changed from a dedicated channel to a common channel to secure an available channel. Checking whether the secured available channel is greater than or equal to the channel capacity for the lake lock; And iv) if the reserved available channel is greater than or equal to the channel capacity for the rock lock, accepting the corresponding handoff call request. Guard channel-based lake rock control method further comprising a. The method of claim 4, wherein In the step (c), And the base station stores information of a non-real-time service call on which a lock lock is performed using a guard channel. The method of claim 5, In step iii), If the gain of the available channel due to channel reconfiguration of the NRT service call is unknown, Requesting, by the base station, to reconfigure a channel from a dedicated channel to a common channel for a non-real-time service call using a guard channel, and determining whether there is a guard channel corresponding to a channel capacity necessary for the requested handoff lock lock; And If it is determined that the handoff is not as many guard channels as the channel capacity necessary for call acceptance, a channel reconfiguration may be requested from a dedicated channel to a common channel for a next non-real-time service call, and thus the handoff call may be accepted. Requesting sequential channel reconfiguration for the non-real-time service call until a channel is secured Guard channel-based lake rock control method comprising a. The method of claim 5, In step iii), If the gain of the available channel according to the channel reconfiguration of the non-real-time service call can be known, Calculating, by the base station, a list of non-real-time service calls that need to reconfigure a channel from a dedicated channel to a common channel to secure channel capacity necessary for accepting the requested handoff call; And Requesting channel reconfiguration of a non-real-time service call according to the calculated list, and accepting the handoff call using a channel secured through the channel reconfiguration Guard channel-based lake rock control method comprising a. The method of claim 8, The guard channel-based lockback control method, characterized in that the non-real-time service list for securing the channel is calculated by the following equation. At this time, Is the available channel capacity obtained when the i-th call is changed from a dedicated channel to a shared channel, Is the capacity of the channel needed to accept a handoff call.