KR20060082357A - Method and apparatus for change of subordinate cell for scheduling soft handover terminals in reverse packet transmission - Google Patents

Abstract

The present invention relates to an efficient reverse traffic rate control of terminals located in a soft handover region, or a method of selecting a serving cell (serving cell) for scheduling and accompanying signaling methods. When a change is made from the current subject cell to another cell, the subject cell is changed using a different method depending on whether the two cells are identical in the radio link set. That is, when the radio link sets are not the same, the radio network controller selects a subordinate cell, and when the radio link sets are the same, the terminal selects the subcell, thereby improving overall system performance by efficiently using reverse resources. Increase stability.

WCDMA, UPLINK ENHANCEMENTS, SERVING CELL CHANGE

Description

METHOD AND APPARATUS FOR SERVING CELL CHANGE FOR SCHEDULING OF MOBILE STATION IN SOFT HANDOFF FOR UPLINK PACKET TRANSMISSION}             

1 is a conceptual diagram illustrating transmission of data through an E-DCH in a general radio link.

2 is a message flow diagram illustrating a transmission and reception procedure through a general E-DCH.

3 is a diagram illustrating a general scheduling method of an E-DCH.

4 shows a soft handover according to a first embodiment of the present invention.

5 is a diagram illustrating a relationship between a cell and a terminal according to the first embodiment of the present invention.

6 is a diagram illustrating the operation of a terminal for a first embodiment of the present invention;

7 is a diagram illustrating an operation of a cell included in a subordinate E-DCH RLS for a first embodiment of the present invention.

8 is a diagram illustrating the operation of a cell included in a non-submissive E-DCH RLS for a first embodiment of the present invention.

9 is a diagram illustrating an operation of a terminal for a second embodiment of the present invention.

FIG. 10 illustrates an operation of a cell for transmitting a relative grant using a dedicated channel in the case of a non-submissive cell according to the second embodiment of the present invention.

FIG. 11 illustrates an operation of a cell for transmitting a relative grant using a common channel in the case of a non-submissive cell according to the second embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wideband code division multiple access (WCDMA) system. In particular, an enhancement-only dedicated terminal is a physical channel for backward packet transmission of terminals located in a soft handoff region. A method and apparatus for enabling efficient scheduling in receiving a channel.

Based on the Global System for Mobile Communications (GSM), a European mobile telecommunications system, the UMTS (Universal Mobile Telecommunication Service) system, the third generation of telecommunications systems using WCDMA, is available to mobile or computer users anywhere in the world. It provides a consistent service for transmitting packet-based text, digitized voice or video and multimedia data at speeds of 2 Mbps and higher. UMTS uses the concept of packet-switched virtual access using a packet protocol such as the Internet Protocol (hereinafter referred to as 'IP'), and can always be connected to any other end in the network.                         

1 is a conceptual diagram illustrating transmission of data through an E-DCH in reverse packet transmission in a general wireless link.

Referring to FIG. 1, a base station 100 supporting an E-DCH and terminals 101 to 104 receiving the E-DCH are configured. The base station 100 determines the channel status of the terminals 101 to 104 using the E-DCH to schedule data transmission of each terminal. Scheduling allocates a low data rate to a terminal far from the base station and a high data rate to a near terminal while ensuring that the measured noise rise of the base station does not exceed the target noise increase to increase the performance of the entire system. Do this by assigning.

2 is a message flow diagram illustrating a transmission and reception procedure through a general E-DCH.

Referring to FIG. 2, in step 202, the base station and the terminal configure an E-DCH. At this time, the message transmission process through a dedicated transport channel (dedicated transport channel). If the E-DCH is configured, the UE informs the base station of the scheduling information in step 204. The scheduling information includes terminal transmission power information indicating reverse channel information, extra power information that can be transmitted by the terminal, and an amount of data to be transmitted in a buffer of the terminal.

The base station that has received the scheduling information from the plurality of terminals in communication, monitors the scheduling information received from the plurality of terminals in order to schedule data transmission of each terminal in step 206. In more detail, in step 208, the base station determines to allow reverse packet transmission to the terminal and transmits scheduling assignment information to the terminal. The scheduling allocation information includes an allowed data rate. In addition, the scheduling assignment information may be transmitted in an absolute grant format that informs the absolute value of the allowed data rate at one time, or a relative value of how the allowed data rate may be changed compared to the previous frame. It may be transmitted in the form of a relative grant.

The UE determines a transport format (TF) of the E-DCH to be transmitted in the reverse direction using the scheduling allocation information in step 210, and transmits reverse (UL) packet data through the E-DCH in steps 212 to 214. At the same time, the TF information is transmitted to the base station. In step 216, the base station determines whether there is an error in the received TF information and the packet data. In step 218, the base station transmits a non-acknowledge (NACK) to the terminal through the ACK / NACK channel when there is an error in any one of the determination results, if there is no error .

When the ACK information is transmitted, the packet data is completed and the terminal transmits new data through the E-DCH. When the NACK information is transmitted, the terminal retransmits the packet data having the same contents through the E-DCH.

Hereinafter, with reference to FIG. 3, the basic transmission and reception procedure through the E-DCH will be described as the operation of the terminal and the base station according to the timing. Here, the base station can be considered the same concept as one cell.

Referring to FIG. 3, the terminal 504 is transmitting a reverse packet to the cell 501 managing the terminal through the E-DCH 506, and the cell 501 is a reverse packet of the terminal 504. Responsible for scheduling. The forward information for scheduling includes an absolute grant 502 and a relative grant 503, and the reverse information includes scheduling request information 505.

When the terminal 504 intends to transmit a reverse packet by using the E-DCH, first, the scheduling request information 505 is transmitted to the cell 501. In this case, the terminal 504 may first transmit the reverse packet of the E-DCH using the transmission rate 1 520, which is a transmission rate within an arbitrary threshold value, without exchanging information with the cell 501.

The cell 501 collects terminal state information of various terminals, determines a transmission rate to be allocated to each terminal through scheduling, and transmits transmission rate allocation information to the corresponding terminal. In this case, the rate allocation information includes an absolute grant 502 and a relative grant 503. If the rate of change is more than one step compared to the previous rate, the absolute grant 502 is used to directly inform the terminal of the allocated rate. On the other hand, if the change in the transmission rate is less than one step compared to the previous transmission rate, the relative grant 503 is used to inform that the transmission rate allocated to the terminal is increased by one step, one step decrease, or constant compared to the previous transmission rate. . A detailed description of the operation of transmitting the rate allocation information will be described later.

The scheduling request information 505 transmitted by the terminal 504 is periodically transmitted or transmitted whenever new data is generated in the buffer of the terminal. Here, the transmission of the scheduling request information 505 whenever new data is generated in the buffer of the terminal 504 is referred to as 'event triggered transmission'.

In detail, when the terminal 504 delivers the scheduling request information of the state 507 to the cell 501 in step 508, the cell 501 determines a transmission rate 509 to be allocated to the terminal 504. In this case, when the transmission rate 509 to be allocated is a transmission rate 10 and the difference is more than one step compared to the transmission rate 1 520 previously transmitted by the terminal 504 using the E-DCH, the cell 501 is an absolute grant ( By using the 510, the terminal 504 informs that the transmission rate assigned is the transmission rate 10 (511). The terminal 504 transmits the next uplink packet to the E-DCH using the absolute grant 510 transmitted by the cell 501. That is, the terminal 504 transmits the reverse packet to the E-DCH using the transmission rate 10 corresponding to the transmission rate 511 using the transmission rate indication information 510 informed by the cell.

In the next time, the cell 501 decides the transmission rate to be allocated to the terminal 504. If the transmission rate 511 is the same as the transmission rate previously used by the terminal, the change of the transmission rate is changed using the rate increase / decrease information. It will tell Keep (512) that it is not present. Since the terminal receiving the relative grant 513 knows to use a constant rate in proportion to the previous packet, the UE transmits the E-DCH using the previously used rate 10 (514).

As described above, the operation of using the rate indication information at the beginning of reverse packet transmission to prevent the delay of the increase of the transmission rate has been described. However, in another case, the rate indication information is changed when the rate to be allocated is changed by one or more steps even during the reverse packet transmission. It can be used to inform the terminal of the actual transmission rate.                         

When new data enters the buffer of the terminal 504, the terminal 504 transmits the terminal state information 515 to the cell 501. Then, the base station transmits an absolute grant 516 indicating the newly allocated transmission rate in order to allocate a larger transmission rate to the terminal. This allows the terminal 504 to transmit the reverse packet at a rate 14 (518), which is one or more steps higher than the previous rate 11 (517).

The basic transmission and reception related operations of the E-DCH and the signaling process of the physical layer of the UE and the cell have been described above. Since the E-DCH is an enhanced channel for packet transmission of the uplink transport channel, it follows the basic characteristics of the dedicated channel. One of them supports soft handover, which means that a terminal in the soft handover area can receive forward information from all of the cells belonging to an active set. That is, the terminal located in the soft handover area receives scheduling allocation information from all cells belonging to the active set in order to transmit the E-DCH. However, if all of the cells belonging to the active set use the same influence on scheduling to the soft handover terminal, the terminal has a problem in which cell to follow the scheduling assignment information coming from.

Accordingly, the terminal has one subordinate cell among cells belonging to the active combination, and receives scheduling allocation information of greater influence from the subordinate cell, and is smaller than the cell belonging to the active combination but not the subordinate cell. Receive scheduling assignment information of influence. As an example, the terminal may receive both the absolute grant and the relative grant from the subject cell. However, since the grant is never received from a cell other than the subordinate cell, only the relative grant can be received, and thus the influence on scheduling between the subordinate cell and the non-subordinate cell may be different.

Since the subordinate cell has a great influence on the scheduling in the UE located in the soft handover region, the performance of the system may depend on which cell is selected as the subordinate cell among the cells included in the active combination. Therefore, there is a need for a method of selecting and changing a subordinate cell that can improve the performance of the system.

Accordingly, the present invention, which was devised to solve the problems of the prior art operating as described above, provides a method for scheduling an enhanced reverse transport channel (E-DCH) of terminals located in a soft handover area in an asynchronous WCDMA communication system.

Another object of the present invention is to provide a method for selecting a subordinate cell in a terminal located in a soft handover area.

In addition, an object of the present invention is to provide a signaling method for sharing selected cell information selected in a terminal located in a soft handover area between a terminal and a base station.

The apparatus according to the first embodiment for achieving the object of the present invention, the soft handover terminal of the mobile communication system using an enhanced reverse channel (E-DCH) including one subcell and a plurality of non-submissive cells In the scheduling apparatus,

One of the non-subscribed cells included in the E-DCH RLS including the subordinate cell is changed into a subordinate cell according to a predetermined criterion, and the first subordinate cell change information indicating the subordinate cell change result is previously submitted. A terminal for transmitting to a cell and the non-submissive cells;

 One of the non-submissive cells not included in the subordinate E-DCH RLS is selected as a subordinate cell according to a predetermined criterion, and the second subordinate cell change information indicating a result of the subordinate cell selection is performed by the UE, the previous subordinate cell, and the non-submissive cell. It characterized in that it comprises a radio network controller for transmitting to the cells.

An apparatus according to a second embodiment of the present invention is a scheduling apparatus for soft handover terminals in a mobile communication system using an enhanced reverse channel including one subordinate cell and a plurality of non-submissive cells.

In the non-subjected cells included in the E-DCH RLS including the subordinate cell, one of cells for setting a relative grant through a dedicated channel is changed into a subordinate cell according to a predetermined criterion, and the result of changing the subordinate cell A terminal for transmitting the first sub-cell change information indicating a previous sub-cell and the non-subdue cell;

 In the non-subjected cells included in the subordinate E-DCH RLS, one of the cells for setting a relative grant through a common channel is selected as a subordinate cell according to a predetermined criterion, and the second subordinate cell change information indicating the subordinate cell selection result is selected. And a radio network controller for transmitting to the terminal, the previous subordinate cell and the non-submissive cells.

In the method according to the first embodiment of the present invention, in the scheduling method of soft handover terminals in a mobile communication system using an enhanced reverse channel (E-DCH) including one subcell and a plurality of non-submissive cells,

Changing one of the non-submissive cells included in an E-DCH RLS including the subordinate cell into a subordinate cell according to a predetermined criterion;

And transmitting the first subject cell change information indicating the result of the subject cell change to a previous subject cell and the non-submitted cells.

Another method of the first embodiment of the present invention is to provide a scheduling method of soft handover terminals in a mobile communication system using an enhanced reverse channel (E-DCH) including one subordinate cell and a plurality of non-submissive cells. ,

Selecting one of the unsubscribed cells not included in an E-DCH RLS including the subordinate cell as a subordinate cell according to a predetermined criterion;

And transmitting the second subject cell change information indicating the result of the selection of the subject cell to the terminal, the previous subject cell, and the non-subjected cells.

According to a second embodiment of the present invention, there is provided a method of scheduling soft handover terminals in a mobile communication system using an enhanced reverse channel including one subordinate cell and a plurality of non-subordinate cells.

Changing one of the cells that set the relative grant through a dedicated channel from the non-subscribed cells included in the E-DCH RLS including the sub-cell into a subordinate cell according to a predetermined criterion;                         

 And transmitting the first subject cell change information indicating the result of the subject cell change to a previous subject cell and the non-subjected cells.

Another method according to the second embodiment of the present invention is a scheduling method of soft handover terminals in a mobile communication system using an enhanced reverse channel including one subordinate cell and a plurality of non-submissive cells.

Selecting one of the cells for setting a relative grant through a common channel among the non-subjected cells included in the subordinate E-DCH RLS as a subordinate cell according to a predetermined criterion;

And transmitting, to the terminal, the previous subordinate cell and the non-subordinated cells, the subordinate cell change information indicating the subordinate cell selection result.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

According to the present invention, in the system supporting the E-DCH, an increase in the forward signaling information generated when the UE is located in the soft handover area and a UE that receives the scheduling assignment information determine the transmission format for the E-DCH. We propose a method of changing a subordinate cell and a signaling method of information involved in order to secure the disadvantage of the method being unclear, to minimize the efficient scheduling and waste of unnecessary resource allocation.

Hereinafter, the operation of E-DCH scheduling of the UE located in the soft handover area according to the first embodiment of the present invention will be described with reference to FIG. 4.

Referring to FIG. 4, cell 1 601 and cell 2 602 may receive an E-DCH, and terminals 603, 606, and 610 transmit an E-DCH. The terminal 603 and the terminal 606 do not belong to the soft handover region and are only E-DCH scheduled by the cell 1 601 and the cell 2 602, respectively. Accordingly, when the UE 603 transmits the E-DCH, the UE 603 receives the scheduling allocation information 604 of the cell 1 601 and transmits the E-DCH 605 using the same. On the other hand, when the UE 606 transmits the E-DCH, it receives the scheduling allocation information 607 from the base station of the cell 2 (602), and transmits the E-DCH (609) using this.

However, the terminal 610 belonging to the soft handover includes both cell 1 601 and cell 2 602 in the activity combination. That is, the terminal 610 may receive the signals transmitted from the cell 1 601 and the cell 2 602, and conversely, the cell 601 and the cell 602 also receive all the signals transmitted from the terminal 610. Can be received. Accordingly, the cells 601 and 602 belonging to the activity combination perform scheduling assignment information 611 and 613 by performing E-DCH scheduling with respect to the UE 610 for E-DCH transmission of the UE 610. Each transmits to the terminal 610.

Since the terminal 610 receives one or more scheduling allocation information from the cell 1 601 and the cell 2 602, the UE 610 determines the transmission format of the E-DCH with one of the cell 1 601 and the cell 2 602. Should be. Therefore, one criterion should be set for the terminal located in the soft handover area, and scheduling should be performed in a different manner from the terminals located in the soft handover area.

Hereinafter, a scheduling method when a terminal located in a soft handover area is scheduled for several cells at the same time.

In the scheduling method, only a subordinate cell transmits an absolute grant to give a big change in a transmission rate of a terminal, and cells that are not subordinate cells can schedule only through a relative grant. The subordinate cell may also transmit a relative grant, and when a relative grant is transmitted from the subordinate cell to the terminal, a dedicated signal using a dedicated channel is used.

However, cells belonging to the active set but not the subordinate cells use a common signal using a common channel instead of a dedicated signal when transmitting a relative grant to the terminal. The relative grant using the common signal is a signal that is included in the active combination but is simultaneously applied to a terminal which does not recognize the cell as a subordinate cell.

Next, two methods for selecting a subordinate cell for terminals belonging to the soft handover region will be described in detail.

The first method is a method in which the RNC receives measurement information of a terminal and thus selects / changes a cell most suitable for the terminal as a subordinate cell.

The second method is a method in which a UE selects and changes a subordinate cell through fast signaling. Although it is possible to change the fast submission cell, in order to change the cell quickly, the cells in the active combination set the absolute grant and the relative grant, which are forward channels for the terminal, in advance.

Since the absolute grant uses a common channel regardless of the subordinate cell, a new channel setting is not necessary. However, the relative grant is transmitted using the common channel only in the cell that is not the subordinate cell. That is, when the terminal changes the current cell into a subordinate cell, the terminal quickly receives a relative grant using a dedicated channel from the new subordinate cell, so that all cells belonging to the active set are counterparts for the terminals located in the soft handover area. There should be one dedicated channel for transmission of grant. That is, a cell belonging to the active set but not the current subordinate cell is not used right now, but since a dedicated channel for changing to the subordinate cell by the terminal must be provided in advance, the code resource of the forward channel is wasted.

Accordingly, the present invention proposes a method for minimizing a delay time occurring when a RNC changes a subordinate cell generated when a subordinate cell is selected and a downlink channel resource wasted when the terminal selects a subordinate cell.

In the first embodiment of the present invention, the subject or RNC subjects a subject to change a subordinate cell according to a radio link set (hereinafter referred to as 'RLS') for an E-DCH of cells belonging to an active set. Suggest how to take.

In the transmission of the E-DCH, cells belonging to the active set respectively configure the E-DCH RLS. The E-DCH RLS refers to cells in which soft grants of relative grants are possible. Accordingly, another cell having a relative grant that is soft-coupled with the relative grant of the subordinate cell is included in the same E-DCH RLS as the subordinate cell, and the E-DCH RLS is a subscribing E-DCH RLS. It is called). On the other hand, a cell having a relative grant in which soft coupling of the relative grant of the subordinate cell is impossible becomes a nonsubmissive cell. Among the non-submissive cell cells, cells in which a soft grant of a relative grant is possible together constitute the same E-DCH RLS, and an E-DCH RLS that does not include a subordinate cell, such as the E-DCH RLS, is a non-submissive E-DCH RLS. do.

In any UE, cells belonging to the subordinate E-DCH RLS may be configured with one serving cell and zero or more non-serving cells. The non-submissive cells belonging to the subordinate E-DCH RLS set up a dedicated channel for the relative grant of the UE in order to have a relative grant that is softly coupled with the subordinate cell, and transmit the relative grant through the sub grant. Therefore, when the UE quickly selects and changes a subordinate cell among cells belonging to the E-DCH RLS, it is not necessary to have a dedicated channel for a relative grant not used before the subordinate cell change.

On the other hand, a cell that does not belong to the subordinate E-DCH RLS in the terminal does not need to transmit a relative grant for the terminal as a dedicated signal using a dedicated channel. Therefore, in general, a cell belonging to a non-subscribed E-DCH RLS transmits a relative grant using a common channel to terminals that include the same cell as the terminal in the active set, but do not include the same cell in the subordinate E-DCH RLS. Therefore, in order for the UE to change a subordinate cell from a current subordinate cell to a cell not included in the subordinate E-DCH RLS, it is necessary to set a dedicated channel for a relative grant dedicated to the nonsubordinate cell changed to a new subordinate cell. That is, in order for the terminal to change the subordinate cell, the non-submissive cell should be included in the active set of the terminal and provided with a dedicated channel for the terminal, which is a disadvantage of inefficient use of forward resources. Bring.

However, when the RNC changes the cell to the subordinate cell, the process of setting up a dedicated channel for the relative grant is possible, thereby eliminating the burden of having a dedicated channel in advance.

That is, in the first embodiment of the present invention, when one of the non-submissive cells existing in the subordinate E-DCH RLS is selected and changed into a subordinate cell, the UE directly selects the subordinate cell and returns the result to the subordinate cell and the non-submissive cells. In case of notifying through signaling and selecting one of cells not present in the subordinated E-DCH RLS, the RNC selects one of the non-submissive cells not present in the subordinated E-DCH RLS based on the measurement of the UE. A change is made to the slave cell and the result of the change is informed to the UE, the slave cell and the non-subscribed cells through RRC signaling and NBAP signaling.

5 is a diagram illustrating a relationship between a cell and a terminal according to the first embodiment of the present invention.

Referring to FIG. 5, the terminal 706 is included in Cell 1 704, Cell 2 705, and Cell 3 703 included in the active set. The Cell 1 704 and the Cell 2 705 belong to the same E-DCH RLS. If the Cell 2 705 is a current subordinate cell, the Cell 1 704 and Cell 2 705 are included. The E-DCH RLS becomes the submissive E-DCH RLS.

On the other hand, cell 3 703 is a non-submissive cell and at the same time configures only a non-submissive E-DCH RLS. Cell 1 704 and cell 2 705 belong to base station 702, cell 3 703 is included in base station 701, and base stations 701 and 702 are both RNC 710. Presided over. In this case, the terminal 706 finds an optimal subject cell among the cells included in the subject E-DCH RLS based on an arbitrary criterion, and when the subject cell needs to be changed, the terminal 706 uses the current subject cell 2 ( In step 705, the information on the change of the subject cell is transmitted to the subject cell to be changed, and the subject cell is changed.

The arrow 712 indicates that the terminal 706 selects the cell 1 704 as the next subordinate cell in the cell 2 705 that is the current subordinate cell, and the terminal 706 selects the cell 1 704 and the cell 2 705. The UE transmits information indicating that the subordinate cell has been changed. Then, the cell 1 704 schedules to use the absolute grant to the terminal 706 to become a new subject cell, while the cell 2 705 no longer obeys the terminal 706. Detecting that it is not a cell, scheduling is performed to the terminal 706 in a direction not to use a grant.

On the other hand, the RNC 710 manages cell 1 704, cell 2 705, and cell 3 703 all at once, and selects an appropriate subordinate cell to the terminal 706. When the subject cell to be selected is included in the same E-DCH RLS as the current subject cell, the RNC 710 does not perform any operation. On the other hand, when the subject cell to be selected is the non-subjected cell 1 703 included in the E-DCH RLS that is different from the current subject cell 705, the subject cell is transmitted to the terminal 706 through RRC signaling. It informs that the cell is changed to a non-submissive cell other than the cell in the subordinate E-DCH RLS, and transmits the change information to the current subject cell 705 and the newly selected subject cell 703 through NBAP signaling. Subsequently, the cell 2 705, which is the current subordinate cell, determines that it is no longer the subordinate cell to the UE 706 and does not belong to the subordinate E-DCH RLS, thereby releasing the setting of the absolute grant as well as the relative grant. On the other hand, cell 3 703, which is a new obedient cell, enables the use of an absolute grant for the terminal 706, and also newly establishes a dedicated channel for the relative grant.

In the above, the process of the UE and the RNC to perform the change of the subject cell according to the E-DCH RLS has been described. In the following description, a process required for changing a subcell of a UE required in this embodiment, and a process required for changing a subordinate cell by a current subordinate cell or a next subordinate cell are described.

6 is a flowchart illustrating an operation procedure according to a change cell of a UE according to a first embodiment of the present invention.

Referring to FIG. 6, in step 801, the UE receives an RRC message from an RNC. The RRC message includes 'subject cell change information' regarding whether to change the current subject cell of the terminal to a non-subject cell included in the non-subject E-DCH RLS.

In step 802, the UE analyzes the subject cell change information to determine whether there is a change in the subject cell. If there is a change in the subject cell as a result of the determination, in step 803, the UE performs a procedure for changing the current subject cell into a non-subjected cell included in the non-subscribed E-DCH RLS. Specifically, the terminal releases the reception of the absolute grant and the relative grant received in the current subordinate cell, and after setting the reception of the absolute grant and the relative grant of the newly set subordinate cell, the terminal returns to step 801. To return.

If there is no change in the current subject cell as a result of the determination, in step 804, the UE measures the state of all cells included in the current subject E-DCH RLS, and selects the most suitable cell as the subject cell among the cells. In this case, as a criterion for the UE to determine a subordinate cell, forward path loss information of a cell, received power information of a common pilot channel (CPICH) of a cell, or reverse load situation information of a cell such as RoT, or HARQ The ratio information of the ACK related to may be used.

Thereafter, when the most suitable cell is selected as the subordinate cell, the UE determines whether the cell selected as the subordinate cell is the same as the current subordinate cell in step 805. The change of the subject cell is always possible only in cells included in the subject E-DCH RLS. If it is determined that the current subject cell does not need to be changed, the terminal returns to step 801 without performing any other operation.

As a result of the determination, if the change of the current subject cell is necessary, the UE transmits the subject cell change information indicating that the current subject cell should be changed to a new subject cell selected by the UE to cells included in the subject E-DCH RLS. . In this case, there may be various methods for transmitting the UE change cell information. The first method is a method for transmitting the ID of the MS through the physical channel after channel coding the ID of the MS. The second method is a method of adding the ID of the subject cell to the header part of the MAC-e and transmitting the data, or by including it in the data to be transmitted when creating the MAC-e PDU. After the UE transmits the cell change information, in step 807, the UE releases the reception of the absolute grant of the current cell and sets the reception of the absolute grant of the new cell.

FIG. 7 illustrates a procedure for changing cell submission of cells included in a current E-DCH RLS according to the first embodiment of the present invention.

Referring to FIG. 7, step 901 indicates the start of operation of a cell included in the subordinate E-DCH RLS. In step 902, the cell indicates whether the subordinate cell is changed from the RNC to the subordinate cell. Receive through.

In step 903, the cell determines whether to change the subordinate cell according to the RNC based on the received NBAP information. If it is determined that the change of the subordinate cell is necessary, the cell is a case where the subordinate E-DCH RLS is changed in step 904, and when the cell is the subordinate cell, the transmission of the absolute grant and the relative grant is canceled, and the cell subtracts the E-DCH RLS. If it is included in the DCH RLS but is not a subordinate cell, transmission of the relative grant is released. That is, a process of releasing the cell from the subject E-DCH RLS is performed. In step 905, the cell is configured as a cell included in the non-submissive E-DCH RLS, which is to set a common relative grant for the UE. Thereafter, the cell is included in the non-submissive E-DCH RLS in the subordinate E-DCH RLS and performs step 906. Step 906 performs a cell related procedure included in the non-submissive E-DCH RLS.

If it is determined in step 903 that the change of the subcell according to the RNC is not necessary, the cell receives the subcell change information from the UE in step 907. In step 908, the terminal determines whether the cell becomes a subordinate cell according to the received subcell change information.

As a result of the determination, when the cell is selected as the subordinate cell, the cell sets an absolute grant for the UE in step 909 and returns to step 902. If it is determined that the cell is not selected as a subordinate cell, the cell returns to step 902 without setting an absolute grant for the terminal in step 910.

8 illustrates a procedure for changing a subordinate cell of cells included in a non-submissive E-DCH RLS according to the first embodiment of the present invention.

Referring to FIG. 8, the process 1001 signifies the start of the operation of the cell included in the non-submissive E-DCH RLS. The process 1001 is the same process as the process 906 of FIG. 9. In step 1002, the cell receives from the RNC an NBAP message in which the subordinate cell contains change information. In step 1003, the cell determines whether to change the subordinate cell according to the RNC based on the received NBAP information.

If it is determined that the change of the subject cell is not necessary, the process returns to step 1001. As the determination result, when the change of the subordinate cell is required, the subordinate E-DCH RLS is changed. In step 1004, the cell releases the cell from the non-submissive E-DCH RLS and releases transmission of the common relative grant. In step 1005, the cell sets one cell included in a cell included in the non-submissive E-DCH RLS as a subordinate cell. That is, the transmission of the dedicated partner grant is set for the terminal. In this case, when the cell is a subordinate E-DCH RLS and is selected as a subordinate cell, transmission of absolute grant is also set. When the cell is a subordinate E-DCH RLS but is not selected as a subordinate cell, absolute grant transmission is not set. The cell is included in the subordinate E-DCH RLS in the non-submissive E-DCH RLS and performs an operation of the cell included in the subordinate E-DCH RLS in step 1006.

Hereinafter, in the second embodiment of the present invention, among the cells belonging to the active set, in particular, the non-submissive cell changes the subordinate cell according to whether the transmission of the relative grant is transmitted using the dedicated channel or the common channel. A method of taking a subject to a terminal or an RNC is described.

In the transmission of the E-DCH, the cells belonging to the active set respectively set a relative grant for the UE located in the soft handover region. The subordinate cell uses the relative grant for the dedicated channel, but the non-submissive cell Accordingly, the relative grant may use a common channel or may use a dedicated channel like the subordinate cell. When the non-submissive cell transmits a relative grant using a dedicated channel, scheduling is performed by using a dedicated relative grant determined to one UE, and when the non-submissive cell transmits a relative grant using a common channel. Although the cell is included in the active set, it has a difference that scheduling is performed using one relative grant for all the UEs which are not regarded as the subordinate cell.

Therefore, in the case where the non-subordinate cell sets the relative grant using the dedicated channel, the terminal grants the relative grant using the preset dedicated channel even if the terminal changes the subcell to one of the non-subordinate cells. Because it can be transmitted, it is not necessary to have a new dedicated channel. That is, the second embodiment of the present invention is a method in which a terminal can quickly change a subordinate cell only in non-submissive cells that set a relative grant using a preset dedicated channel. On the other hand, when the non-submissive cell belonging to the active set sets up the relative grant using the common channel, the RNC changes the subordinate cell only when the subordinate cell is changed to the non-submissive cell.

9 is a flowchart illustrating a procedure for changing a subordinate cell of a terminal supporting a second embodiment of the present invention.

Referring to FIG. 9, in step 1101, the UE receives an RRC message including the subcell change information from the RNC. In step 1102, the terminal analyzes the received cell change information to determine whether there is a change in the current cell. If there is a change in the subordinate cell as a result of the determination, in step 1103, the UE performs a procedure for changing the subordinate cell from the current subordinate cell to another cell indicated by the RNC. That is, the reception of the absolute grant and the relative grant received in the current subordinate cell is released, the reception of the absolute grant and the relative grant of the newly set subordinate cell is set, and the process returns to step 1101.

If there is no change in the subordinate cell as a result of the determination, in step 1104, the UE measures the state of all cells transmitting the relative grant using its own dedicated channel, and selects the most suitable cell as the subordinate cell from among the cells. As a criterion for the UE to determine a subordinate cell, information related to forward path loss information of a cell, reception power information of a common pilot channel (CPICH) of a cell, or reverse load situation information of a cell such as RoT, or HARQ ACK rate information and the like may be used.

Subsequently, when the most suitable cell is determined as the subordinate cell, in step 1105, the terminal determines whether the selected subordinate cell is the same as the current subordinate cell, and determines whether the change of the current subordinate cell is necessary. If it is determined that the change of the subordinate cell is not necessary, the terminal returns to step 1101 without performing another operation.

If it is determined that the change of the subject cell is necessary, the terminal transmits 'subject cell change information' to the current subject cell and the new subject cell selected by the terminal in step 1106. The subject cell change information should be transmitted to cells transmitting a relative grant using the dedicated channel, and there may be various methods of transmitting the same. The first method is a method of channel coding the ID of the subject cell and then transmitting it through a physical channel. The second method is to add the ID of the subject cell to the header part of the MAC-e and transmit it, or to include it in the data when creating the MAC-e PDU. Thereafter, in step 1107, the UE sets reception of an absolute grant from a subordinate cell to be changed. That is, the reception of the absolute grant of the current subordinate cell is canceled and the reception of the absolute grant of the new subordinate cell is set to be possible.

10 is a procedure of a cell for transmitting a relative grant using a dedicated channel when the cell is a non-submissive cell.

Referring to FIG. 10, in step 1201, the cell receives 'subject cell change information' from the terminal, and in step 1202, the cell determines whether the cell becomes a subordinate cell according to the subject cell change information. If it is determined that the cell is a subordinate cell, in step 1203, the cell sets an absolute grant to allow the terminal to schedule the absolute grant using the absolute grant.

As a result of the determination, when the cell is not determined to be a subordinate cell, the cell enables scheduling of the UE using only the relative grant without setting an absolute grant in step 1204. When steps 1203 to 1204 are performed, the process returns to step 1201.

11 is a procedure of a cell for transmitting a relative grant using a common channel when the cell is a non-submissive cell.

In step 1301, the cell receives 'change information of the subordinate cell' from the RNC through NBAP signaling, and in step 1302, the cell determines whether the cell is a subordinate cell. If it is determined that the cell is a subordinate cell, in step 1303, the cell sets an absolute grant and a relative grant using a dedicated channel for the terminal. If it is determined that the cell is not a subordinate cell, the cell sets only a relative grant using a common channel in step 1304.

The method of the present invention described above may be somewhat specific, but is not limited to the above description, and 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 method described above, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

The present invention, in the asynchronous WCDMA communication system using the E-DCH in the cell belonging to the E-DCH RLS in order to efficiently schedule the terminal located in the soft handoff area in performing the rate scheduling for the reverse packet transmission In contrast, the UE, on the contrary, in the cell that does not belong to the subordinate E-DCH RLS, the RNC performs a process of changing the subordinate cell. In addition, the UE uses a relative grant as a dedicated channel as a non-subscribed cell and, on the contrary, in a cell using a common channel, the RNC performs a process of changing a subordinate cell so that a fast and effective subject cell is not wasted as much as possible by forward code resources. Has the effect of changing

Claims (21)

A scheduling apparatus for soft handover terminals in a mobile communication system using an enhanced reverse channel (E-DCH) including one subcell and a plurality of non-submissive cells, A terminal for changing one of the non-submissive cells included in an E-DCH RLS including the subordinate cell into a subordinate cell according to a predetermined criterion;  And a radio network controller for selecting one of the non-submissive cells not included in the subordinate E-DCH RLS as a subordinate cell according to a predetermined criterion. The method of claim 1, wherein the terminal, Receiving the second subject cell change information from the radio network controller, analyzing the second subject cell change information, and determining whether there is a change in the current subject cell, If there is a change in the subordinate cell as a result of the determination, the reception of the absolute grant and the relative grant received in the current subordinate cell is canceled, and the absolute grant and the relative grant reception of the selected subordinate cell are set according to the 'subject cell selection information'. Device characterized in that. The method of claim 1, wherein the terminal changes the subject cell. The apparatus includes forward path loss information of cells included in the subordinate E-DCH RLS, received power information and reverse information of a common pilot channel of the cell, and an ACK rate when retransmitted. The method of claim 1, wherein the first subordinate cell change information transmission method comprises: Transmit the ID of the subject cell through a physical channel and transmit it through a physical channel, or add the ID of the subject cell to the header of the MAC-e, or include it in the data to be transmitted when creating a MAC-e PDU. Device characterized in that. The method of claim 1, wherein the cells included in the submissive E-DCH RLS, Receiving second subcell change information from the radio network controller, determining whether a change of the current subcell is necessary according to the second subcell change information, and As a result of the determination, if the change of the subordinate cell is necessary, the transmission of the absolute grant and the relative grant of the current subordinate cell is canceled, and the current grant cell is set to a cell not included in the subscribing E-DCH RLS to set the relative grant through the common channel. And set to receive. The method of claim 5, wherein if the determination result does not require a change of the subordinate cell, Receiving the first obey cell change information from the terminal, confirming whether the current cell is a subject cell, and if the current cell is a subject cell, setting an absolute grant for the terminal. The method of claim 1, wherein the cells not included in the submissive E-DCH RLS, When receiving the second subcell change information from the radio network controller and analyzing the second subcell change information and changing the current subcell, the subcell to be changed is released from the non-submissive E-DCH RLS and is common. Release the transmission of the other grant, And configure the changed subject cell to subject E-DCH RLS. A scheduling apparatus for soft handover terminals in a mobile communication system using an enhanced reverse channel including one subcell and a plurality of non-submissive cells, A terminal for changing one of the cells for setting a relative grant through a dedicated channel to a subordinate cell according to a predetermined criterion in non-submissive cells included in an E-DCH RLS including the subordinate cell; And a wireless network controller for selecting one of the cells for setting up a relative grant through a common channel in the non-subjected cells included in the subordinate E-DCH RLS as a subordinate cell according to a predetermined criterion. The method of claim 8, wherein the cell for transmitting the relative grant using the dedicated channel, The first grant cell change information is received from the terminal, and according to the first change cell change information, it is determined whether the cell becomes a change cell to be changed, and if it is determined that the change cell is to be changed, the absolute grant Device for setting the. The method of claim 8, wherein the cell for transmitting a relative grant using the common channel, Receiving change information of a first subordinate cell from the radio network controller, determining whether the cell is a subordinate cell according to the first subordinate cell change information, And if the cell is a subordinate cell, setting a relative grant using an absolute grant and a dedicated channel for the terminal. A scheduling method of soft handover terminals in a mobile communication system using an enhanced reverse channel (E-DCH) including one subordinate cell and a plurality of non-submissive cells, Changing one of the non-submissive cells included in an E-DCH RLS including the subordinate cell into a subordinate cell according to a predetermined criterion; And transmitting the first subject cell change information indicating a result of the subject cell change to a previous subject cell and the non-submitted cells. The method of claim 11, Receiving, from a radio network controller, one of the non-submissive cells not included in the subordinate E-DCH RLS as a subordinate cell according to a predetermined criterion, and receiving second subordinate cell change information indicating a result of the subcell selection; Determining whether there is a change in the current subject cell by analyzing the second subject cell change information; If there is a change in the subordinate cell as a result of the determination, the reception of the absolute grant and the relative grant received in the current subordinate cell is canceled, and the absolute grant and the relative grant reception of the selected subordinate cell are set according to the 'subject cell selection information'. And further comprising a process. The method of claim 11, wherein the criterion for changing the subject cell is: And forward path loss information of cells included in the subordinate E-DCH RLS, received power information and reverse information of a common pilot channel of the cell, and an ACK ratio in retransmission. A scheduling method of soft handover terminals in a mobile communication system using an enhanced reverse channel (E-DCH) including one subordinate cell and a plurality of non-submissive cells, Selecting one of the unsubscribed cells not included in an E-DCH RLS including the subordinate cell as a subordinate cell according to a predetermined criterion; And transmitting second change cell change information indicating a result of the selection of the slave cell to the terminal, a previous cell and the non-subscribed cells.  The method of claim 14, wherein the cells included in the submissive E-DCH RLS, Receiving second subcell change information from the radio network controller; Determining whether a change of the current subordinate cell is necessary according to the second subordinate cell change information; Releasing transmission of the absolute grant and the relative grant of the current subordinate cell if the change of the subordinate cell is necessary as a result of the determination; And setting a current subordinate cell to a cell not included in the subordinate E-DCH RLS and receiving a relative grant through a common channel. The method of claim 15, wherein if the determination result does not require a change of the subordinate cell, Receiving whether the first cell change information is received from the terminal to determine whether the current cell is a cell; If the current cell is a subordinate cell, setting an absolute grant for the terminal. The method of claim 14, wherein the cells not included in the submissive E-DCH RLS, Receiving the second plurality of cell change information from the wireless network controller; If it is necessary to change the current cell by analyzing the second cell change information, canceling the transmission of the common counterpart by releasing the cell to be changed in the non-subscribed E-DCH RLS; And setting the changed subject cell to the subject E-DCH RLS. A method of scheduling soft handover terminals in a mobile communication system using an enhanced reverse channel including one subcell and a plurality of non-submissive cells, Changing one of the cells for setting the relative grant through the dedicated channel in the non-subscribed cells to the subordinate cell according to a predetermined criterion; And transmitting the first subject cell change information indicating the result of the subject cell change to a previous subject cell and the non-submitted cells. 19. The method of claim 18, wherein the cell for transmitting the relative grant using the dedicated channel, Receiving the first plurality of cell change information from the terminal; Determining whether the cell becomes a change cell to be changed according to the first change cell change information; And if it is determined that the subject cell is to be changed, setting an absolute grant. A method of scheduling soft handover terminals in a mobile communication system using an enhanced reverse channel including one subcell and a plurality of non-submissive cells, Selecting one of the cells for setting the relative grant through the common channel in the non-subscribed cells as the subordinate cell according to a predetermined criterion; And transmitting, to the terminal, the previous subordinate cell and the non-submissive cells, the subordinate cell change information indicating the subordinate cell selection result. 21. The method of claim 20, wherein the cell for transmitting a relative grant using the common channel, Receiving change information of a subordinate cell from the radio network controller, and determining whether the cell is a subordinate cell according to the subordinate cell change information; And if the cell is a subordinate cell, setting a relative grant using an absolute grant and a dedicated channel for the terminal.

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