KR20060009793A - Method and apparatus for scheduling of mobile station in soft handoff area for uplink packet transmission - Google Patents

Abstract

The present invention relates to a scheduling method of a base station and an associated signaling method for controlling an efficient reverse traffic rate of terminals located in a soft handover region. The combination of activities of terminals located in the soft handover area includes optimal base stations and non-optimal base stations. The non-optimal base stations transmit the appropriate common scheduling allocation information while performing the scheduling using the common channel for scheduling that can efficiently use the forward channel resources while improving system performance. The terminal combines and interprets the common scheduling assignment information to improve system stability and overall performance.

WCDMA, UPLINK ENHANCEMENTS, SOFT HANDOVER, E-DCH, NODE B CONTROL SCHEDULING, COMMON SCHEDULING ASSIGNMENT, DESIGNATED SCHEDULING ASSIGNMENT

Description

TECHNICAL AND APPARATUS FOR SCHEDULING OF MOBILE STATION IN SOFT HANDOFF AREA FOR UPLINK PACKET TRANSMISSION}             

1 is a diagram illustrating a radio access network (UTRAN) of a UMTS system.

2 is a hierarchical diagram illustrating an interface between a terminal and a radio network controller (RNC).

3 is a conceptual diagram illustrating transmission of data over an E-DCH in a typical radio link.

4 is a message flow diagram illustrating a transmission and reception procedure through an E-DCH.

5 is a diagram for explaining a rate scheduling method.

6 illustrates a time-rate scheduling method.

7 is a diagram illustrating E-DCH transmission of a UE located in a soft handover region.

8 is a diagram illustrating a common scheduling allocation method of a non-optimal base station according to a preferred embodiment of the present invention.

9 is a diagram illustrating an operation of a terminal receiving scheduling allocation information according to an exemplary embodiment of the present invention.

10 illustrates an example of determining a joint scheduling allowance value according to a preferred embodiment of the present invention.

The present invention relates to asynchronous wideband code division multiple access (WCDMA) communication. In particular, the present invention relates to efficient scheduling when terminals located in a soft handover area receive an enhanced dedicated channel for reverse packet transmission. It relates to a method and an apparatus for enabling this.

Third generation, based on the European mobile system Global System for Mobile Communications (GSM) and General Packet Radio Services (GPRS), and using Wideband Code Division Multiple Access (CDMA) UMTS (Universal Mobile Telecommunication Service) system, a mobile communication system, is a consistent service that enables mobile phone or computer users to transmit packet-based text, digitized voice or video, and multimedia data at high speeds of 2 Mbps or more anywhere in the world. To provide. UMTS uses the concept of virtual access, which is a packet-switched connection that uses a packet protocol such as Internet Protocol (IP), and can always be connected to any other end in the network.

FIG. 1 is a diagram illustrating a UMTS Terrestrial Radio Access Network (hereinafter referred to as UTRAN) of a UMTS system.

Referring to FIG. 1, the UTRAN 12 is composed of radio network controllers (hereinafter referred to as RNCs) 16a and 16b and Node B's 18a, 18b, 18c, and 18d. Then, the user equipment (hereinafter referred to as UE) 20 is connected to the core network 10. There may be a plurality of cells below the node Bs 18a, 18b, 18c, and 18d, and each RNC 16a, 16b controls the corresponding node Bs 18a, 18b, 18c, and 18d. Each node B 18a, 18b, 18c, and 18d controls corresponding lower cells. One RNC and Node Bs and cells controlled by the RNC are collectively referred to as a Radio Network Subsystem (hereinafter referred to as RNS) 14a and 14b.

The RNCs 16a and 16b allocate or manage radio resources of the Node Bs 18a to 18d that they control. Node Bs 18a through 18d provide actual radio resources. Radio resources are configured for each cell, and radio resources provided by the Node Bs 18a to 18d mean radio resources of cells managed by the Bs. The terminal 20 may configure a radio channel and perform communication using radio resources provided by a specific cell of a specific Node B. From the standpoint of the terminal 20, the distinction between the Node Bs 18a to 18d and the corresponding cells is meaningless, and since only the physical layer configured for each cell is recognized, the Node Bs 8a to 18d and the cells have the same meaning. Will be mentioned.

The interface between the terminal 20 and the RNCs 16a and 16b is called a Uu interface, and a detailed hierarchical structure is shown in FIG. 2. The Uu interface is divided into a control plane used to exchange control signals between the terminal and the RNC and a user plane used to transmit actual data.

Referring to FIG. 2, the control plane signal 30 includes a radio resource control (RRC) layer 32, a radio link control (RLC) layer 40, a media access control (MAC) layer 42, and physical (physical) signals. The user plane information 32 is processed through a Packet Data Control Protocol (PDCP) layer 36, a Broadcast / Multicast Control (BMC) layer 38, and an RLC layer 40. ), The MAC layer 42, and the physical layer 44. Among the layers shown here, the physical layer 44 is located in each cell, and the MAC layer 42 to the RRC layer 34 are located in the RNC.

The physical layer 44 is a layer that provides an information transmission service using a radio transfer technology, and corresponds to a first layer of an Open Systems Interconnection (OSI) model. The physical layer 44 and the MAC layer 42 are connected by transport channels, and transport channels are defined by the manner in which specific data is processed in the physical layer.

The MAC layer 42 and the RLC layer 40 are connected via logical channels. The MAC layer 42 delivers the data delivered by the RLC layer 40 through the logical channel to the physical layer through the appropriate transport channel, and the data delivered by the physical layer 44 through the transport channel through the appropriate logical channel. It serves to convey to 40. In addition, by inserting additional information into the data received through the logical channel or the transmission channel or by analyzing the inserted additional information, it takes appropriate action and controls the random access operation. The portion related to user plane 30 in this MAC layer 42 is called MAC-d, and the portion related to control plane 32 is called MAC-c.

The RLC layer 40 is responsible for establishing and releasing logical channels. The RLC layer 40 may operate in one of three operation modes such as an acknowledgment mode (AM), an unacknowledged mode (UM), and a transparent mode (TM), and provide different functions for each operation mode. In general, the RLC layer 40 is responsible for dividing or assembling a service data unit (hereinafter referred to as SDU) from an upper layer into an appropriate size, and an error correction function.

The PDCP layer 36 is located above the RLC layer 40 in the user plane 32. The PDCP layer 36 compresses and restores headers of data transmitted in the form of IP packets, and provides a service to a specific terminal with mobility. It is responsible for the lossless transfer of data, etc. under the situation that is changed.

The characteristics of the transport channel connecting the physical layer 44 and upper layers define physical layer processing such as convolutional channel encoding, interleaving, and service-specific rate matching. It is determined by the transport format (TF).

In particular, in the UMTS system, an enhanced uplink dedicated channel is further improved to further improve the performance of packet transmission in uplink (UL) communication from a user equipment (UE) to a base station (BS). : Hereinafter referred to as E-DCH). E-DCH supports technologies such as Hybrid Automatic Retransmission Request (HARQ) and Node B controlled scheduling to support more stable high-speed data transmission.

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

Referring to FIG. 3, reference numeral 100 denotes a Node B supporting the E-DCH, and reference numerals 101, 102, 103, and 104 are terminals that receive the E-DCH. The node B 100 determines the channel status of the terminals 101 to 104 using the E-DCH and schedules data transmission of the terminals 101 to 104. The scheduling allocates a low data rate to the terminal 104 far from the node B 100 while keeping the measured noise rise value of the node B not exceeding the target value in order to increase the performance of the entire system. The terminal 101 is performed by assigning a high data rate.

4 is a message flow diagram illustrating a transmission and reception procedure through an E-DCH.

Referring to FIG. 4, in step 202, the Node B and the UE configure an E-DCH. The configuration process 202 includes the delivery of messages over a dedicated transport channel. When the E-DCH is configured, the UE informs the Node B of the scheduling information in step 204. The scheduling information may include 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.                         

Receiving scheduling information from a plurality of terminals in communication, the Node B monitors scheduling information of the plurality of terminals in step 206 to schedule data transmission of each terminal. In detail, in step 208, the Node B determines to allow backward packet transmission to the terminal and transmits scheduling assignment information to the terminal. The scheduling allocation information includes the maximum allowed data rate and the allowed timing.

The UE determines a transport format (TF) of the E-DCH to be transmitted in the reverse direction by using the scheduling assignment information in step 210, and transmits reverse (UL) packet data through the E-DCH in step 212. At the same time, the TF information is transmitted to the Node B. In step 216, the node B determines whether there is an error in the TF information and the packet data, as shown in step 216. In step 218, the node B receives a non-acknowledge (NACK) when an error occurs in any one of the determination results, and receives an acknowledgment (ACK) when all errors are found through the ACK / NACK channel. Send to the terminal.

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

Since E-DCH is an enhanced channel for packet transmission of a transport channel, it has the basic characteristics of a dedicated channel, one of which is soft handover support. That is, the terminal in the soft handover area may receive forward information from all of the base stations belonging to the active set. Accordingly, the terminal located in the soft handover area receives scheduling allocation information from all of the base stations belonging to the active set in order to transmit the E-DCH. As a result, since the terminal receives different scheduling allocation information from the base stations belonging to the activity set, it is necessary to determine whether to transmit the E-DCH.

Accordingly, in a communication system supporting the E-DCH according to the prior art, in scheduling a terminal in a soft handover area, all base stations belonging to the activity set transmit scheduling allocation information for each terminal, thereby transmitting code resource or transmission power of a forward channel. There is an overhead problem in terms of resources, and it is difficult for a terminal receiving the plurality of scheduling allocation information to determine transmission of an E-DCH.

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

The present invention provides a scheduling method and apparatus for base stations of base stations which are included in an activity set in a terminal located in a soft handover area and which are not optimal base stations.

The present invention provides a method and apparatus for determining a transmission rate of reverse packet transmission using scheduling information received from base stations included in an activity set in a terminal located in a soft handover area.

In accordance with another aspect of the present invention, a scheduling method for a user terminal in soft handover in a mobile communication system supporting enhanced reverse packet data service is provided.

The user terminal communicating with one optimal base station and at least one non-optimal base station by soft handover;

Receiving, by the user terminal, dedicated scheduling assignment information according to dedicated scheduling assignment from the optimal base station;

Receiving, by the user terminal, at least one scheduling permission indicator according to a common scheduling assignment from the at least one non-optimal base station;

Determining a combined scheduling permission indicator by combining at least one scheduling permission indicator received from the at least one non-optimal base station;

Determining a transmission format of a reverse packet according to the dedicated scheduling assignment information and the combined scheduling permission indicator.

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.

The present invention clearly determines the E-DCH transmission format while reducing forward signaling information generated due to scheduling of terminals located in a soft handover region in an enhanced reverse packet data service, and provides more efficient scheduling in terms of reverse resource management. It's about optimal scheduling techniques that make it possible. The present invention also proposes a scheduling technique by a base station (hereinafter referred to as a non-optimal base station) other than the optimal scheduling base station (hereinafter referred to as optimal base station) which is included in the activity combination. In addition, the present invention proposes a method in which a UE located in a soft handover region receives and interprets scheduling allocation information of the optimal base station and scheduling allocation information of non-optimal scheduling.

As a scheduling method for reverse packet transmission, various methods may be used. Rate scheduling and time and rate scheduling are described as representative scheduling methods. Rate scheduling is a method in which the base station controls the transmission rate of each terminal step by step, and time-rate scheduling is a method in which the base station simultaneously controls the time and transmission rate of the reverse packet transmission of the terminal. The following two scheduling methods will be described.

5 is a diagram illustrating transmission of control information in a reverse direction and a forward direction for transmission rate scheduling and transmission of a reverse packet.

The terminal 502 is transmitting a rate request information 505 and an enhanced decidated channel (E-DCH) data 506, which is a reverse packet, and the base station 501 transmits a maximum rate allowed to the terminal through scheduling. Rate grant information (503, RG) indicating allowed max rate) is being transmitted. The rate allowance indicator includes three pieces of information: 'UP', 'DOWN', and 'KEEP'.

The terminal 502 determines how much data is in the buffer to be sent in the reverse direction, and also checks the power surplus value that the terminal 502 can transmit to the base station 501 through the transmission rate request information 505 indicating a desired transmission rate. ) To increase or decrease the data rate. The base station 501 that receives the rate request information 505 increases the maximum rate of the terminal 502 by combining the rate request information of the terminal 502 and other terminals managed by the base station 501. Whether to UP, DOWN, or KEEP is determined using the rate allowance information 503.

Referring to FIG. 5, in more detail, in step 507, the terminal 502 requests a rate increase using the rate request information 508. The base station 501 receiving the rate request information 508 performs scheduling in the interval 509 and then instructs the terminal 502 to increase the rate using the rate allowed information 510. Accordingly, the terminal 501 can transmit the reverse packet in the next section 512 at the transmission rate 11 which is increased by one step compared to the transmission rate 10 used in the existing section 511.                     

In the rate scheduling described above, the base station and the terminal have information on transmission rates that the terminal can use. The information about the transmission rates may be represented by, for example, a transport block combination (hereinafter, referred to as "TBS") used in the WCDMA scheme.

6 is a diagram illustrating transmission of uplink and forward control information and transmission of uplink packets for time-rate scheduling.

Referring to FIG. 6, the terminal 603 transmits terminal state information 604 including the data amount and transmission power of the data buffer to the base station 601 periodically or in an event-triggered manner. The base station 601 determines the maximum transmission rate of the terminal during the next interval through scheduling with reference to the terminal state information 604, and uses the scheduling assignment information (SA) 602 to the terminal 603. Notify me. Accordingly, the terminal 603 receives the scheduling allocation information 602 and transmits the E-DCH data 605 in the reverse direction for a predetermined time interval within the maximum transmission rate indicated by the scheduling allocation information 602.

For example, when the terminal 603 transmits the terminal state information 621 to the base station 601 in the interval 611, the base station 601 performs scheduling to allow the terminal 603 to transmit the E-DCH during the next interval. In this case, the transmission rate to be allowed to the terminal 603 is determined. Accordingly, the base station 601 transmits allocation time information and allocation rate information to the terminal 603 by using the scheduling allocation information 641 in a section 631. The terminal 603 receiving the scheduling allocation information 641 transmits E-DCH data according to a predetermined transmission rate during the time interval 651 based on the scheduling allocation information 641. The scheduling assignment information 641 indicates a transmission rate 10 during the time interval 651. On the other hand, since the base station 601 did not allocate the time interval to the terminal 603 in the interval 630, the terminal 603 uses the rate 1, which is the minimum set, in the time interval 650. Send it.

Of course, when the rate scheduling method and the time-rate scheduling are used simultaneously, the rate scheduling using the rate allowance indicator is generally used, and when a sudden change in the rate such as the occurrence or exhaustion of data or an urgent change in channel conditions is required. It is also possible to use time-rate scheduling using rate allocation information.

7 illustrates an operation of a terminal located in a soft handover area to perform an enhanced reverse packet data service.

In FIG. 7, the terminals 703, 706, and 710 may transmit the E-DCH. The terminal 710 is located in the soft handover area and the base stations 701 and 702 related to the soft handover area are included in the activity set of the terminal 710. The terminals 703 and 706 do not belong to the soft handover area and communicate only with the respective base stations 701 and 702. In order to support the E-DCH, the terminal 703 receives the scheduling assignment information 704 from the base station 701 and transmits the E-DCH data 705. Similarly, in order to support the E-DCH, the terminal 706 receives the scheduling assignment information 707 from the base station 702 and transmits the E-DCH data 708.                     

However, the terminal 710 belonging to the soft handover area has all of the base stations 701 and 702 in the activity combination, and receives the scheduling from the base stations 701 and 702. The base stations 701 and 702 belonging to the activity combination may perform the scheduling in the same way for the terminal 710 in the soft handover area. On the other hand, the base stations 701 and 702 belonging to the activity combination may perform scheduling with different scheduling rights for the terminal 710. At this time, the base station having the maximum scheduling authority for the terminal 710 becomes the optimal base station of the terminal 710.

The terminal 710 has base stations 701 and 702 in the activity combination, and one optimal base station is determined among the base stations 701 and 702 belonging to the activity combination. For example, a base station that is most affected by reception noise in terms of transmitting E-DCH in the reverse direction may be defined as an optimal base station. In general, a base station closest to a terminal, a reverse channel situation, a base station having a good forward channel condition, or one base station having a margin for a reverse resource is defined as an optimal base station.

In FIG. 7, the base station 701 is an optimal base station of the terminal 710, and the base station 702 is a non-optimal base station. The terminal 710 receives both signals transmitted from the optimal base station 701 and the non-optimal base station 702, and the optimal base station 701 and the non-optimal base station 702 also receive all signals transmitted from the terminal 710. Receive.

When both the optimal base station 701 and the non-optimal base station 702 send dedicated scheduling assignment information to all terminals including themselves in the activity combination, transmission power or code resources due to forward signaling Consumption inevitably increases in the back. Therefore, in this case, the base stations 701 and 702 may have problems such as insufficient transmission power or insufficient channel codes. In particular, the UE belonging to the soft handover area communicates with two or more base stations included in the activity combination, and the signaling information requires very large forward signal strength due to its characteristics. Therefore, the problem concerning the consumption of the transmission power and the code resources described above becomes more serious.

As a method for solving this problem, the scheduling allocation method proposed in the preferred embodiment of the present invention will be described with reference to FIG.

In FIG. 7, the optimal base station 701 has higher authority than the non-optimal base station 702 in scheduling the terminal 710. That is, the optimal base station 701 can schedule the terminal 710 in a more detailed and accurate manner, and the non-optimal base station 702 can only schedule roughly the terminal 710 compared to the optimal base station 701. It is possible. Therefore, the optimal base station 701 performs dedicated scheduling in scheduling the terminal 710, and the non-optimal base station 702 allocates scheduling to the terminal 710 in common with other terminals. Perform (Common scheduling). This common scheduling allocation method can reduce forward resource consumption and can solve a problem of transmission power or lack of code resources of a base station.

8 is a diagram illustrating a common scheduling allocation method of a non-optimal base station according to a preferred embodiment of the present invention.

Referring to FIG. 8, the terminals 804 and 805 are located in the soft handover area. Terminal 804 manages an activity combination comprising base stations 801, 802, 803, of which base station 801 is the optimal base station of terminal 804. Terminal 805 manages an activity combination comprising base stations 802 and 803, of which base station 803 is the optimal base station of terminal 805. In the scheduling of the E-DCH, the optimal base stations 801 and 803 respectively schedule respective terminals using dedicated signals, and non-optimal base stations schedule the terminals at the same time using a common signal. In this case, rate scheduling or time-rate scheduling may be used, or both scheduling methods may be used. That is, the optimal base station 801 of the terminal 804 transmits dedicated scheduling allocation information 806 to the terminal 804, and the optimal base station 803 of the terminal 805 also transmits dedicated scheduling allocation information (eg, to the terminal 805). 807).

On the other hand, since the base station 802 is a non-optimal base station for both the terminal 804 and the terminal 805, the terminal 804 and 805 are commonly scheduled using one common scheduling assignment information 808. That is, the base station 802 forwards the common scheduling allocation information 808 in the forward direction for the terminals 804 and 805 including the base station 802 in the activity combination and configured as the non-optimal base station. The common scheduling assignment information 808 indicates the maximum transmission rate of the reverse link for all of the terminals 804 and 805. Accordingly, the terminals 804 and 805 receive the common scheduling assignment information 808 transmitted from the base station 802 and use the same to determine the transmission format of the E-DCH.

Since the terminal 804 sets the base station 803 as the non-optimal base station, the terminal 804 receives the common scheduling allocation information 809 transmitted from the base station 803. The common scheduling assignment information 809 transmitted from the base station 803 should be received in common with the other terminals configured as non-optimal base stations while including the base station 803 in the activity combination, in addition to the terminal 804. Information. Terminals receiving scheduling allocation information from the one or more base stations combine the one or more scheduling allocation information to determine a transmission format of the E-DCH that the terminal can transmit.

As described above, the UE located in the soft handover area receives a dedicated scheduling assignment from the optimal base station and a common scheduling assignment from the non-optimal base station, and the terminal determines the transmission format of the E-DCH by combining two or more scheduling assignment information. . Hereinafter, a method in which a terminal uses common scheduling allocation information of a non-optimal base station and a method in which a terminal located in a soft handover region interprets two or more scheduling allocation information will be described in detail.

<< first embodiment >>

According to the first embodiment, the non-optimal base station performs common scheduling assignment using two levels. The optimal base station uses an independent dedicated scheduling allocation method for the terminals, and the non-optimal base station uses one common scheduling allocation method for the multiple terminals. That is, the optimal base station simultaneously uses both rate scheduling and time-rate scheduling, or other possible scheduling methods for dedicated scheduling allocation. On the other hand, the non-optimal base station uses a scheduling grant indicator of 1 bit according to the rate scheduling for common scheduling assignment. As described above, when the 1-bit scheduling allowance indicator is used as the common scheduling allocation information, it is possible to save consumed base station transmission power and channel code resources.

As an example, two levels represented by the 1-bit scheduling allowance indicator indicate a down signal ("DOWN") and an ignore signal ("Don't Care"), respectively. The scheduling enable indicator of 1 bit means a down signal when the real value +1 on the physical channel, and the ignore signal when the real value -1 on the physical channel. In other cases, the real values have the opposite meaning to the above case.

As another example, real values are mapped to the scheduling permission indicator in consideration of the frequency of the falling signal and the frequency of the disregarding signal. That is, when a signal predicted to occur less frequently is mapped to a real value 0 that uses a non-transmission (DTX) method on a physical channel, transmission power and noise are saved by saving power consumed by the physical channel when transmitting the signal. Benefits may be gained in terms of For example, if the ignore signal is generated more frequently on average than the down signal, the ignore signal is mapped to a real value of 0 on the physical channel and transmitted by nontransmission, and the down signal is transmitted to the real value 1 (or on a physical channel). -1) and transmit it. In such a case, the receiver determines one of the two signals using a threshold value other than zero.

The common scheduling allocation method performed by the non-optimal base station is as follows.

The base station manages uplink resources by measuring reception strengths of terminals included in the base station in performing scheduling. In this case, if the reception strength of the terminals that set the base station as the non-optimal base station is very large, and has a great influence on the terminals having the base station as the optimum base station or the terminals including only the base station in the activity combination, A scheduling allow indicator for all terminals or terminals configured as themselves non-optimal base stations is set as a down signal. On the contrary, if the reception strength does not significantly affect the base station and there is room in the reverse resource of the base station, the base station sets the scheduling permission indicator for the terminals as a disregard signal.

The operation of the terminal for the first embodiment will be described with reference to FIG. 9 below. A terminal located in the soft handover area has one optimal base station and one or more non-optimal base stations.

Referring to FIG. 9, the terminal receives dedicated scheduling allocation information 901 from the optimal base station. In this case, the dedicated scheduling assignment information 901 becomes a Rate Grant (RG) signal when a rate scheduling method is used, and becomes a Scheduling Assignment (SA) signal when a time-rate scheduling method is used. When both methods are used, a combination of a rate permission signal and a scheduling assignment signal is obtained. In addition, the terminal receives n scheduling allowance values 902 to 903 from n non-optimal base stations (where n is an integer greater than or equal to 1). Here, the scheduling permission value means a real value of the scheduling permission indicator. The terminal combines the n scheduling permission values 902 to 903 through a predetermined scheduling permission combining function 904 to obtain one combined scheduling permission value 905. The scheduling allow combining function 904 will be described in detail below.

The combined scheduling allowance value 905 found from the n scheduling allowance values 902 to 903 is inputted to a scheduling determination function 906 along with dedicated scheduling assignment information 901 received from an optimal base station, so that the terminal is assigned to E. The terminal determines the final scheduling allocation value necessary for determining the format of the DCH, and the UE determines the E-DCH format 907 to be used for uplink transmission using the scheduling allocation value determined by the scheduling determination function 906. The scheduling decision function 906 will also be described in detail later.

The scheduling allow combining function 904 of FIG. 9 is used when the number of non-optimal base stations of the terminal is greater than two, and the following operations are possible.

As a first example, the scheduling allow combining function 904 determines the combined scheduling allowance of the non-optimal base stations as the down signal if any one of the scheduling allowance values received by the terminal indicates a down signal. That is, the terminal determines the combined scheduling allowance value of the non-optimal base stations as the disregard signal only when all the scheduling allowance values indicate the disregard signal, and otherwise determines the downlink signal.

As another example, the terminal combines scheduling allowance values of the non-optimal base stations using the weighted sum. The weight sum is to use a weight value set for each non-optimal base station. In FIG. 10, a weighted sum combining method of the scheduling allowance values will be described in detail.

Referring to FIG. 10, when n scheduling allowance values 1001, 1002, and 1003 are received from n non-optimal base stations configured for the UE, the scheduling allowance values 1001 to 1003 are respectively assigned weight values 1005. , 1007, 1009 and multipliers 1006, 1008, 1010, and then add up by summer 1011. The weight value determined for each non-optimal base station may be set in a network such as an RNC according to a cell type to inform the terminal, or the terminal may be internally set according to a channel condition between base stations.

That is, the scheduling allowance value 1001 received at the first non-optimal base station is multiplied by the weight value 1005 set for the first non-optimal base station at the multiplier 1006 and input to the summer 1011, and the second non-optimal base station. The scheduling allowance value 1002 received at the optimal base station is multiplied by the weight value 1007 set for the second non-optimal base station at the multiplier 1008 and entered into the summer 1011, in this way at all non-optimal base stations. The received scheduling allowance values 1001-1003 are multiplied by the weights 1005-1009, respectively, and are input to the summer 1011.

Summer 1011 adds the scheduling allowance values multiplied by the weights 1005-1009 to produce one weighted sum value. Then, the combined scheduling allowance value 1012 is determined according to the weighted sum value. For example, the combined scheduling allowance value 1012 is determined according to a result of comparing the weighted sum value with a predetermined threshold. That is, if the scheduling permission indicator has a real value of +1, it means a down signal, and if it has a real value of -1, it means a disregard signal, the threshold becomes '0'. Therefore, when the weighted sum value is greater than or equal to 0, the combined scheduling allowance value is determined as a down signal, and when the weighted sum value is less than 0, the combined scheduling allowance value is determined as an ignore signal. In addition, if the down signal is a real value 0 and the ignore signal is a real value +1 (or -1), the threshold will be '0.5' (or '-0.5').

The scheduling determination function 906 of FIG. 9 receives the combined scheduling allowance value determined above and the dedicated scheduling allocation information of the optimal base station received by the terminal, and determines a scheduling allocation value so that the terminal can determine the format of the E-DCH to be transmitted. Output If the combined scheduling allowance value means 'don't care', it means that the non-optimal base station of the terminal is not significantly affected by the use of reverse resources even if the E-DCH transmission format of the terminal is changed to some extent. do. Accordingly, the terminal determines the transmission format of the E-DCH according to the dedicated scheduling allocation information transmitted by the optimal base station.

On the other hand, if the combined scheduling allowance value is 'DOWN', it means that the E-DCH transmission of the UE is a burden on the reverse resource utilization of the non-optimal base station. That is, the 'DOWN' means a command to lower the transmission rate by one step when the rate scheduling is used in the E-DCH transmission, and to limit the transmission of the E-DCH when time-rate scheduling is used. It means command.

In this case, if all terminals located in the soft handover region determine the transmission format of the E-DCH by lowering the transmission rate of the E-DCH by one step according to the 'down' signal, or limit the transmission itself, individual situations of the terminals are considered. As a result, they are less efficient in terms of system performance and fairness. Therefore, the following methods may be additionally used as a method for passing this.                     

In the first method, a stochastic 'falling' decision method is used. If the probability randomly generated through the probability test is greater than a predetermined value, the terminal follows the 'down' determination of the combined scheduling allowance value, otherwise, the terminal ignores the 'down' determination of the combined scheduling allowance value. When the combined scheduling allowance value determined as 'falling' is ignored, the terminal uses the format of the previous frame as it is in determining the format of the E-DCH or uses the scheduling allocation information of the optimal base station as it is.

In the second method, when rate scheduling is used, it is determined whether or not to accept the 'down' decision according to the transmission rate of the terminal currently being used. The terminal has a constant rate threshold. If the transmission rate of the currently transmitting E-DCH is greater than the threshold, the terminal follows the decision to 'fall down' the combined scheduling allowance value since the non-optimal base station may be greatly affected by the E-DCH transmission of the terminal. . On the other hand, if the transmission rate of the currently transmitted E-DCH is smaller than the threshold, since the non-optimal base station is not significantly affected by the E-DCH transmission of the terminal, the terminal does not follow the 'down' determination of the combined scheduling allowance value. Without maintaining the current rate or following scheduling allocation information of the optimal base station.

In a third method, it is determined whether to accept the 'down' decision according to the service level of the E-DCH of the UE. The terminal providing the E-DCH service may be initially given a grade, which indicates the quality of the E-DCH service of the terminal. The criteria for dividing the rating may be charging or channel status of the terminal user.                     

As an example, the higher-level terminal uses scheduling allocation information of the optimal base station regardless of receiving the 'down' signal, and the lower-level terminal lowers the E-DCH transmission rate by one step depending on whether the 'down' signal is received. . As another example, the terminal has a different probability value according to the grade, and when the probability randomly generated by the probabilistic test using the probability value is larger than a predetermined reference value, the UE determines the 'falling down' determination of the combined scheduling allowance value. Ignore the 'down' determination of the combined scheduling allowance value. When the combined scheduling allowance value is ignored, the UE uses the previous frame format as it is in determining the format of the E-DCH or uses the scheduling allocation information of the optimal base station as it is.

The class information of each terminal may be delivered to the base station, which may be directly transmitted to the base station by the network or the terminal during the initial terminal setup process. When the base station knows the class of the terminal, the scheduling allocation information may be selected by predicting how much of the terminals located in the soft handover region to follow the scheduling allocation information of the base station.

As a fourth method, the UE receiving the E-DCH is signaled separately from the RNC by a method of interpreting the down signal of the non-optimal base station. That is, the RNC informs each terminal of how to interpret the 'down' signal from the non-optimal base station during soft handover using RRC signaling, and the terminal determines the transmission rate of the E-DCH using the RNC signaling information.

For example, the RNC informs the decision method to be 1 and 0 according to the state of the terminal. A UE signaled with 1 uses scheduling allocation information of an optimal base station regardless of receiving a 'down' signal, whereas a UE signaled with '0' decreases an E-DCH rate by one step according to the reception of a 'down' signal. give. As another example, the RNC signals each terminal a reference value used for probability test of the soft handover region. Accordingly, when the non-optimal base station transmits a 'down' signal, if the probability randomly generated by the probabilistic test using the probability value is larger than the reference value, the terminal follows the 'down' determination of the combined scheduling allowance value. The case ignores the 'down' determination of the combined scheduling allowance value. If the combined scheduling allowance value is ignored, the UE uses the previous frame format as it is in determining the format of the E-DCH or uses scheduling allocation information of the optimal base station.

The RNC may also transmit the signaling information transmitted to the terminal to the base station, thereby more efficiently scheduling the base station. That is, the base station knows an analysis method when the terminals receive the 'down' signal from the non-optimal base station during the soft handover, and predicts how much of the terminals located in the soft handover region will follow the scheduling allocation information of the base station. To select the scheduling assignment information.

The scheduling determination function 906 may perform various combinations using scheduling allowance indicators from the non-optimal base station and scheduling allocation information from the optimal base station in addition to the two methods described above, and output a scheduling allocation value according to the combination. Eventually, the output of the scheduling determination function 906 becomes final scheduling information for determining the format of the E-DCH to be transmitted by the terminal, and the terminal determines the format of the E-DCH using the scheduling information.

<< 2nd Example >>

According to the second embodiment of the present invention, the non-optimal base station performs common scheduling assignment using three levels. That is, the second embodiment shows three levels of a scheduling permission indicator as a down signal 'DOWN', a margin down signal 'MARGINAL DOWN', and a disregard signal 'Don't care'. In addition, the optimal base station performs scheduling through independent dedicated scheduling allocation information to the terminals, and the non-optimal base station performs scheduling through a single common scheduling allocation information to several terminals. That is, the optimal base station simultaneously uses rate scheduling, time-rate scheduling, or both, or all other scheduling methods for dedicated scheduling allocation. On the other hand, the common scheduling allocation method of the non-optimal base station controls transmission rates at three levels by using a scheduling grant indicator.

The scheduling permission indicator according to the common scheduling assignment means a down signal when the real value +1 on the physical channel, a neglect signal when the real value -1 on the physical channel, and a real value that is not transmitted. If it has zero, it means margin down signal. In other cases, the three values +1, -1, and 0 may be combined with signals of other meanings.

As an example, real values are mapped to the scheduling allowance indicator by considering the frequency of occurrence of the down signal, the ignore signal, and the margin down signal, respectively. That is, a real value 0 that takes a method of non-transmission (DTX) on a physical channel is mapped to a signal predicted to have a low occurrence frequency. The transmission of the signal by the non-transmission method saves power consumed in the physical channel, and thus, gain can be simultaneously obtained in terms of reducing transmission power and noise reduction. For example, if the ignore signal is generated more frequently than the down signal and the margin down signal, the terminal maps the ignore signal to a real value of 0 on the physical channel and transmits the non-transmission method by the non-transmission method. The real value 1 and the margin down signal are mapped to -1 and transmitted.

The common scheduling allocation method performed by the non-optimal base station is as follows.

The base station manages uplink resources by measuring reception strengths of terminals included in the base station in performing scheduling. In this case, when the reception strength of the terminals for which the base station is set to the non-optimal base station is very large, the base station is the terminal when the base station is used as the optimal base station, or if the base station is included in the activity combination. Set the scheduling permission indicator to the descending signal. On the contrary, if the reception strength does not significantly affect the base station and there is room for reverse resources of the base station, the base station sets the scheduling permission indicator for the terminals as a disregard signal. In addition, although the reception strength affects the base station to some extent, the non-optimal base station has a relatively relaxed situation in the utilization of reverse resources, or the reverse resources of the base station have a margin by restricting all backward transmission of the terminals. In this case, the base station sets the scheduling permission indicator for the terminals to the margin down signal. In other words, the margin down signal is instructed to reduce the backward rate less forcibly than the down signal.

The operation of the terminal for the second embodiment will be described again with reference to FIG. 9. A terminal located in the soft handover area has one optimal base station and one or more non-optimal base stations.

Referring to FIG. 9, the terminal receives scheduling allocation information 901 from an optimal base station. In this case, the dedicated scheduling assignment information 901 becomes a rate allowance (RG) signal when the rate scheduling method is used, and becomes a scheduling assignment (SA) signal when the time-rate scheduling method is used. When used, this is a combination of the rate allowed signal and the scheduling assignment signal. The terminal also receives n scheduling allowance values 902 to 903 from n non-optimal base stations (where n is an integer greater than or equal to 1). Here, the scheduling permission value means a real value of the scheduling permission indicator. The terminal combines the n scheduling allowance values 902 to 903 through a predetermined scheduling allowance combining function 904 to obtain one combined scheduling allowance value 905. The scheduling allow defect function 904 will be described in detail below.

The combined scheduling allowance value 905 found from the n scheduling allowance values 902 to 903 is inputted to a scheduling determination function 906 together with dedicated scheduling assignment information 901 received from an optimal base station, so that the terminal is assigned to E. The terminal determines the final scheduling allocation value necessary to determine the format of the DCH, and the UE determines the E-DCH format 907 to be used for the uplink transmission using the scheduling allocation value determined by the scheduling determination function 906. The scheduling decision function 906 will also be described in detail later.

The scheduling allow combining function 904 of FIG. 9 is used when the number of non-optimal base stations of the terminal is greater than two, and the following operations are possible.

As a first example, the scheduling allow combining function 904 uses a reference setting method that uses a falling signal as a preferential reference. That is, the scheduling allow combining function 904 determines the combined scheduling allowance of the non-optimal base stations as the lowering signal if any one of the scheduling allowance values received by the terminal indicates the lowering signal. If all of the scheduling allowances are not a down signal, the following reference is used as the margin down signal. That is, the scheduling allow combining function 904 determines the combined scheduling allowance of the non-optimal base stations as the margin lowering signal if all of the scheduling allowance values received by the terminal are not the lowering signal but indicate at least one margin lowering signal. Finally, if all scheduling allowance values received by the terminal are all disregard signals, the scheduling allow combining function 904 determines the combined scheduling allowance of the non-optimal base stations as the disregard signal.

As another example, the terminal combines scheduling allowance values of the non-optimal base stations using the weighted sum. The weight sum is to use a weight value set for each non-optimal base station. Likewise, with reference to FIG. 10 mentioned above, the weighted sum combining method of the scheduling allowable weighted sums according to the second embodiment will be described in detail.                     

Referring to FIG. 10, when n scheduling allowance values 1001, 1002, and 1003 received from n non-optimal base stations configured for the UE are received, the scheduling allowance values 1001 to 1003 are respectively assigned predetermined weight values 1005. , 1007, 1009 and multipliers 1006, 1008, 1010, and then add up by summer 1011. Summer 1011 adds the scheduling allowance values multiplied by the weights 1005 to 1009 to produce one weighted sum value. The joint scheduling allowance value 1012 is then determined according to the weighted sum value.

The combined scheduling allowance value 1012 is determined by comparing the weighted sum value with two predetermined thresholds. For example, if the scheduling allowance indicator has a real value of +1, it means a down signal, and if it has a real value of 0, it means a margin down signal, and if it has a real value of -1, it means a negation signal. The resulting thresholds are one value (value 1) between +1 and 0 and another value (value 2) between 0 and -1. Therefore, if the weighted sum value is greater than (value 1), the combined scheduling allowance value is determined as a down signal, and if the weighted sum value is less than (value 2), the combined scheduling allowance value is an ignored signal. Is determined. When the weighted sum value is located between the (value 1) and the (value 2), the combined scheduling allowance value is determined as a margin down signal. The (value 1) and the (value 2) may be a predetermined value, a value notified through higher signaling from the RNC, or a value selected by the terminal.

As another example, the scheduling allow combining function 904 combines the two examples described above. Specifically, the scheduling allow combining function 904 preferentially determines the combined scheduling allowance as the lowering signal when there is at least one lowering signal among the scheduling allowances based on the lowering signal. The combined scheduling allowance value is determined using the weighted sum method of the down signal and the ignore signal. Here, a threshold between 0 and -1 is used to distinguish the margin down signal and the ignore signal.

The scheduling determination function 906 of FIG. 9 receives the combined scheduling allowance value determined above and dedicated scheduling allocation information of the optimal base station received by the terminal and outputs scheduling information so that the terminal can determine the format of the E-DCH to be transmitted. do. When the combined scheduling allowance value means 'don't care', it means that the non-optimal base station of the terminal is not significantly affected by the reverse resource use even if the E-DCH transmission format of the terminal is changed to some extent. . Accordingly, the terminal determines the format of the E-DCH using the dedicated scheduling allocation information transmitted by the optimal base station.

On the other hand, if the combined scheduling allowance value is 'DOWN', it means that the E-DCH transmission of the UE is a burden on the reverse resource utilization of the non-optimal base station. Accordingly, the UE determines the transmission format of the E-DCH by unconditionally lowering the maximum allowed rate of the E-DCH according to the 'down' signal.

Finally, if the combined scheduling allowance value is 'MARGINAL DOWN', this means that the E-DCH transmission of the UE may be a relatively large burden for the use of reverse resources by the non-optimal BS. That is, the combined scheduling allowance value is 'MARGINAL DOWN', which means that the non-optimal base station commands the terminal to set a rate by one step to all of the terminals or terminals that set themselves as non-optimal base stations (rate of scheduling). Case, or a command that limits the E-DCH transmission itself (in case of time-rate scheduling). Accordingly, the following methods are used as in the 'down' signal of the first embodiment.

In the first method, a stochastic 'falling' decision method is used. If the probability randomly generated through the probability test is greater than a predetermined value, the UE interprets the 'border reduction' decision of the combined scheduling allowance value as a 'down' signal to reduce the transmission rate of the E-DCH by one step. Ignores the combined scheduling allowance value. When the combined scheduling allowance value is ignored, the UE uses the previous frame format as it is in determining the format of the E-DCH or uses the scheduling allocation information of the optimal base station as it is.

In the second method, when rate scheduling is used, it is determined whether or not to accept the 'margin lowering' decision according to the transmission rate of the terminal currently being used. The terminal has a constant rate threshold. If the transmission rate of the currently transmitting E-DCH is larger than the threshold, the UE determines the 'margin lowering' of the combined scheduling allowance value since the non-optimal base station may be greatly affected by the E-DCH transmission of the UE. Interpretation as a 'down' signal reduces the transmission rate of the E-DCH by one step. On the other hand, when the transmission rate of the currently transmitted E-DCH is smaller than the threshold, since the non-optimal base station is not significantly affected by the E-DCH transmission of the terminal, the terminal ignores the combined scheduling allowance value and leaves the current transmission rate as it is. Maintain or follow scheduling allocation information of the optimal base station.

In a third method, a UE receiving an E-DCH may be initially given a grade. The grade may be connected to a grade of the quality of the E-DCH of the UE and determine a transmission rate of the E-DCH according to the grade. It's a way of taking things differently. The criteria for dividing the rating may be charging of the user of the terminal or channel status. The terminal has a predetermined class, the operation is changed when receiving a 'blank margin' signal according to the class. The higher level terminal uses the scheduling assignment information of the optimal base station regardless of the reception of the 'down margin' signal, while the lower level terminal determines the signal as a 'down' signal according to the reception of the 'down margin' signal. In this case, a method of lowering the E-DCH transmission rate by one step may be selected. In addition, if a probability randomly generated by a probabilistic test using the probability value is greater than a predetermined value with a different probability value according to the grade, the signal 'falling margin' is interpreted as 'falling' of the combined scheduling allowance value. If the case ignores the combined scheduling allowance value. When the combined scheduling allowance value is ignored, the UE uses the previous frame format as it is in determining the format of the E-DCH or uses the scheduling allocation information of the optimal base station as it is. The class information of each terminal may be delivered to the base station, which may be delivered directly to the base station by the network or the terminal during the initial terminal setup process. When the base station knows the class of the terminal, it is possible to predict how much of the terminals located in the soft handover area to follow the scheduling allocation information of the base station, so that it can be used as an efficient variable in selecting the scheduling allocation information.                     

The fourth method is a method in which a UE receiving an E-DCH is separately signaled from a RNC to interpret a 'blank margin' signal of the non-optimal base station. That is, the RNC informs each UE of how to interpret the 'border down' signal that can come from the non-optimal base station in soft handover using RRC signaling, and the UE uses the signaling information of the RNC to transmit the E-DCH rate. It is a way to take different ways to determine. For example, the RNC informs the decision method to be 1 and 0 according to the state of the terminal, and the terminal which has signaled 1 uses the scheduling allocation information of the optimal base station as it is by determining the 'blank margin' signal as an 'ignore' signal. In response to the signal '0', the UE may select a method of reducing the E-DCH transmission rate by one step by judging the 'border down' signal as the 'down' signal. As another example, the RNC signals each terminal a probability value used for probability testing of the soft handover region. Accordingly, when the non-optimal base station transmits a 'blank margin' signal, when the probability randomly generated by a probabilistic test using the signaled probability value is greater than the value signaled by the RNC, the combined scheduling allowance value is determined. The 'border down' signal is determined to be a 'down' signal, otherwise the combined scheduling allowance value is ignored. When the combined scheduling allowance value is ignored, the UE uses the previous frame format as it is in determining the format of the E-DCH or uses the scheduling allocation information of the optimal base station as it is. The information transmitted by the RNC to the terminal can be transmitted to the base station as well, so that scheduling of the base station can be more efficiently performed. That is, when the base station knows how to interpret when the terminal receives a 'blank margin' signal from the non-optimal base station in soft handover, how much of the terminals located in the soft handover region will follow the scheduling allocation information of the base station. It can be used as a single efficient variable in selecting scheduling allocation information.

The scheduling determination function 906 may perform various combinations using scheduling allowance indicators from the non-optimal base station and scheduling allocation information from the optimal base station in addition to the two methods described above, and output a scheduling allocation value according to the combination. Eventually, the output of the scheduling determination function 906 becomes final scheduling information for determining the format of the E-DCH to be transmitted by the terminal, and the terminal determines the format of the E-DCH using the scheduling information.

In the above two embodiments, a non-optimal base station schedules terminals located in a soft handover area through a scheduling allowance indicator, and the terminal allocates a scheduling allowance indicator received from the non-optimal base station and a dedicated scheduling assignment received from an optimal scheduling base station. The method of determining the format of the E-DCH to be transmitted using the information has been described. As the scheduling permission indicator, the first embodiment shows two levels of the down signal and the ignore signal, and the second embodiment shows three levels of the down signal and the margin down signal and the ignore signal.

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. In detail, another modified embodiment of the present invention may indicate more levels with the scheduling permission indicator, thereby giving more flexibility in performing common scheduling by the non-optimal base station. 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 can reduce the consumption of the transmission power of the base station and the consumption of the forward channel code resources due to the transmission of the forward scheduling information signal for the scheduling of the terminals located in the soft handover area, and proposes an additional interpretation method of the terminal. By using the common scheduling information to propose a method that can perform a different function for each terminal.

Claims (18)

A scheduling method for a user terminal in soft handover in a mobile communication system supporting enhanced reverse packet data service, The user terminal communicating with one optimal base station and at least one non-optimal base station by soft handover; Receiving, by the user terminal, dedicated scheduling assignment information according to dedicated scheduling assignment from the optimal base station; Receiving, by the user terminal, at least one scheduling permission indicator according to a common scheduling assignment from the at least one non-optimal base station; Determining a combined scheduling permission indicator by combining at least one scheduling permission indicator received from the at least one non-optimal base station; And determining a transmission format of a reverse packet according to the dedicated scheduling assignment information and the combined scheduling allowance indicator. The method of claim 1, wherein the at least one scheduling permission indicator, And a down signal indicating lowering a maximum rate for the enhanced reverse packet data service or an ignoring signal indicating to follow the dedicated scheduling allocation information. The method of claim 2, wherein the determining of the combined scheduling permission indicator comprises: If the at least one scheduling permission indicator includes at least one down signal, the combined scheduling permission indicator is determined to be a down signal, and if the at least one scheduling permission indicator is all ignored, the combined scheduling permission indicator is determined to be an ignore signal. Said method, characterized in that. The method of claim 2, wherein the determining of the combined scheduling permission indicator comprises: Compute a weighted sum value by applying the weights assigned to the corresponding non-optimal base stations to the at least one scheduling allowance indicator, and compare the weighted sum value with a predetermined threshold to lower the combined scheduling allowance indicator signal or The method according to claim 1, characterized in that determined by the ignore signal. The method of claim 2, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a disregard signal, the transmission format is determined according to the dedicated scheduling allocation information; if the combined scheduling allowance indicator is a down signal, the transmission format is determined according to the combined scheduling allowance indicator. Way. The method of claim 5, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a falling signal, a randomly generated probability value is compared with a predetermined value, and if the probability value is greater than or equal to one, the transmission format of the reverse link is reduced by one step to determine the transmission format. If it is small, the transmission format is determined according to the dedicated scheduling allocation information or the transmission format of a previous frame. The method of claim 5, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a down signal, the current reverse rate of the user terminal is compared with a predetermined threshold; if the current reverse rate is greater than or equal to the threshold, the reverse rate is reduced by one step to determine the transmission format. And if the current reverse rate is less than the threshold, determining the transmission format according to the dedicated scheduling allocation information or the transmission format of the previous frame. The method of claim 1, wherein the at least one scheduling permission indicator, A round down signal indicating to lower the maximum rate for the enhanced reverse packet data service, an ignore signal indicating to follow the dedicated scheduling allocation information, or a margin lowering signal indicating to lower the allowed maximum rate if necessary. Said method, characterized in that. The method of claim 8, wherein the determining of the combined scheduling permission indicator comprises: If the at least one scheduling permission indicator includes at least one down signal, the combined scheduling permission indicator is determined as a down signal, and the scheduling permission indicator including the down signal does not exist, and includes at least one margin down signal. And if the scheduling permission indicator is present, the combined scheduling permission indicator is determined to be a marginal down signal, and if the scheduling permission indicator is all ignored, the combined scheduling permission indicator is determined to be a disregard signal. The method of claim 8, wherein the determining of the combined scheduling permission indicator comprises: Compute a weighted sum value by applying the weights assigned to the corresponding non-optimal base stations to the at least one scheduling allowance indicator, and compare the weighted sum value with a predetermined threshold to lower the combined scheduling allowance indicator signal or The method as claimed in claim 2, characterized in that it is determined by a margin down signal or a ignore signal. The method of claim 8, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a disregard signal, the transmission format is determined according to the dedicated scheduling allocation information. If the combined scheduling allowance indicator is a down signal, the maximum transmission rate of the reverse link is reduced by one step to determine the transmission format. And if the combined scheduling allowance indicator is a margin down signal, determining the transmission format according to the dedicated scheduling allocation information or the down signal. The method of claim 11, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a margin down signal, a randomly generated probability value is compared with a predetermined value; if the probability value is greater than or equal to one, the maximum transmission rate of the reverse link is reduced by one step to determine the transmission format. If the value is small, the transmission format is determined according to the dedicated scheduling allocation information or the transmission format of a previous frame. The method of claim 11, wherein the determining of the transmission format comprises: If the combined scheduling allowance indicator is a blanking down signal, the current reverse rate of the user terminal is compared with a predetermined threshold value, and if the current reverse rate is greater than or equal to, the reverse rate is reduced by one step to determine the transmission format. And if the current reverse rate is small, determining the transmission format according to the dedicated scheduling allocation information or the transmission format of the previous frame. The method of claim 1, wherein the dedicated scheduling assignment information, And a round down signal indicating to lower the maximum rate for the enhanced reverse packet data service, a sustain signal indicating to maintain the maximum rate, or a rounding signal indicating to raise the maximum rate by one step. . The method of claim 1, wherein the dedicated scheduling assignment information, And a scheduling assignment signal indicative of a maximum rate for the enhanced reverse packet data service. The method of claim 1, wherein the dedicated scheduling assignment information, A rate permission signal including a down signal for downgrading the maximum data rate for the enhanced reverse packet data service, a maintenance signal for maintaining the maximum data rate, or a round up signal for upping the maximum data rate; And a scheduling assignment signal indicating the maximum data rate. The method of claim 1, wherein the determining of the transmission format of the reverse packet comprises: Each terminal determines a transmission format of a reverse packet according to the combined scheduling allowance indicator or determines a transmission format of a reverse packet according to the dedicated scheduling assignment information by using a probability value set differently according to a class set for each terminal. Said method. A scheduling method for a user terminal in a mobile communication system supporting a reverse packet data service, The user terminal communicating with one optimal base station and at least one non-optimal base station by soft handover; Receiving, by the user terminal, dedicated scheduling assignment information according to dedicated scheduling assignment from the optimal base station; Receiving, by the user terminal, at least one scheduling permission indicator according to a common scheduling assignment from the at least one non-optimal base station; Determining a transmission format of a reverse packet by using the dedicated scheduling allocation information and the at least one scheduling permission indicator. The method of claim 1, wherein in determining the transmission format of the uplink packet, whether to use only the dedicated scheduling allocation information or the at least one scheduling permission indicator together is determined through higher signaling.

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