KR20060040549A - Method for scheduling of mobile station in soft hand-over area for up-link packet transmission - Google Patents

Abstract

The present invention relates to a scheduling method for controlling an efficient reverse traffic rate of mobile terminals located in a soft handover region. An active set of terminals located in the soft handover region includes an optimal base station and non-optimal base stations.

In the present invention, the wireless network controller transmits the section information for controlling the reverse overload of the base station of the neighboring base station and the neighboring cell of the mobile station communicating with the mobile station, and the mobile terminal uses the section information. And not transmitting a rate request bit for a predetermined period. Or a step in which the radio network controller transmits section information indicating that the overload of the neighboring base station is valid to its cell base station and allocates a reverse data rate smaller than before during the section information. In addition, a process of newly allocating a section indicating validity of the overload is considered in consideration of a plurality of mobile terminals having different transmission time intervals.

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

Description

Scheduling method of mobile station in mobile communication system transmitting backward packet {METHOD FOR SCHEDULING OF MOBILE STATION IN SOFT HAND-OVER AREA FOR UP-LINK PACKET TRANSMISSION}             

1 is a configuration diagram schematically showing a radio access network (UTRAN) of a third generation mobile communication system to which the present invention is applied.

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

3 is a conceptual diagram illustrating transmission of data through an E-DCH to which the present invention is applied.

4 is a message flow diagram illustrating an E-DCH transmission / reception procedure to which the present invention is applied.

5 is a diagram illustrating a scheduling operation of a mobile terminal located in a soft handover area according to the present invention.

FIG. 6 illustrates signaling for transmitting and receiving valid interval information between an RNC and a UE according to a first embodiment of the present invention; FIG.

7 is a flowchart illustrating an operation of transmitting reverse data of a mobile station having received valid section information according to a first embodiment of the present invention.

8 is a flowchart illustrating an operation of retransmitting reverse data by a mobile terminal having received valid section information according to the present invention.                 

9 is a diagram illustrating signaling for transmitting and receiving valid section information between an RNC and a base station according to a second embodiment of the present invention;

10 is a flowchart illustrating an operation of a base station receiving valid section information according to the present invention.

FIG. 11 is a diagram illustrating an operation of a signaling and a system for setting a length of an overloaded bit and a valid period in consideration of a transmission time interval of a mobile terminal according to a third embodiment of the present invention.

The present invention relates to asynchronous wideband code division multiple access (WCDMA) communication. In particular, a mobile terminal located in a soft handover region provides an efficient scheduling method for reverse packet transmission.

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.

The UMTS uses the concept of virtual connection, which is a packet-switched connection using 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 a transport channel connecting the physical layer 44 and upper layers include physical layer processing such as convolutional channel encoding, interleaving, and service-specific rate matching. It is determined by the transport format (TF) specified.

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 in order 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 improve 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. If the E-DCH is configured, the UE informs the Node B of the scheduling information in step 204. The scheduling information may be 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. Specifically, 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 may include an absolute grant that immediately informs the maximum data rate allowed and a relative grant that increases, decreases, or maintains the maximum allowable data rate compared to a previous value. . In this case, the absolute grant and the relative grant, which are the scheduling allocation information, may be transmitted by dedicated signaling used for each terminal, and common signaling signaled to one or more terminal groups or all the terminals belonging to one cell. may be transmitted in common signaling.

The UE determines a transport format (TF) of the E-DCH to be transmitted in the reverse direction 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 assignment information from all 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 active 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 region, all base stations belonging to the active set transmit scheduling allocation information for each terminal, thereby transmitting code resources or transmission power of the 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, an object of the present invention, which was devised to solve the problems of the prior art operating as described above, is to provide an improved uplink transmission channel (E-DCH) scheduling method for terminals located in a soft handover area in an asynchronous mobile communication system. have.

Another object of the present invention is to provide a method for performing scheduling in consideration of base stations which are included in an active set and not optimal base stations in a terminal located in a soft handover area.

Another object of the present invention is to provide a method for determining a transmission rate of reverse packet transmission using scheduling information received from base stations included in an active set in a terminal located in a soft handover region.

Another object of the present invention is to provide a method for a terminal located in a soft handover area to receive interval information indicating validity of scheduling assignment information of a non-optimal base station from a wireless network controller.

Another object of the present invention is to provide a method for an optimum base station located in a soft handover area to receive interval information indicating validity of scheduling assignment information of a non-optimal base station from a wireless network controller.

Another object of the present invention is to provide a method for newly setting interval information indicating validity of scheduling allocation information of a predetermined base station in an active set in consideration of different transmission time intervals of a plurality of mobile terminals located in a soft handover area. have.

Another object of the present invention is to provide a method for setting a transmission length for transmitting scheduling allocation information in consideration of different transmission time intervals of a plurality of mobile terminals located in a soft handover area.

It is still another object of the present invention to provide a method for setting a sinusoidal transmission time interval as a valid interval of scheduling allocation information of a base station in an active set among different transmission time intervals of a plurality of mobile terminals located in a soft handover region.

In accordance with another aspect of the present invention, a method for allocating a reverse radio resource by a mobile station in a mobile communication system for transmitting reverse packet data, wherein the wireless network controller communicates with the mobile terminal. Transmitting interval information indicating the validity of the overload bit of the neighboring base station adjacent to the base station of the own cell to be performed by the mobile terminal and not transmitting the rate request bit for the interval determined by the mobile station. It is characterized by including.

Another preferred embodiment of the present invention devised to achieve the above objects is a mobile communication including a base station located in a soft handover area to control its own cell and a mobile terminal communicating with an adjacent base station adjacent to the base station. A method of transmitting reverse data by a mobile station in a system, the method comprising: receiving, by a mobile terminal, interval information indicating validity of an overload bit of a neighboring base station from a radio network controller; During the process of receiving the scheduling allocation information, and the interval information, the reverse data is transmitted in consideration of the scheduling allocation information of the neighboring base station without considering the scheduling allocation information received from the base station of the own cell.

Another preferred embodiment of the present invention devised to achieve the above objects is a mobile device comprising a base station located in a soft handover area to control its own cell and a mobile terminal communicating with an adjacent base station adjacent to the base station. A method of transmitting reverse data by a mobile terminal in a communication system, the method comprising: receiving, by the mobile terminal, scheduling allocation information from a base station of the own cell and the neighboring base station, and scheduling allocation information transmitted from the neighboring base station If the information indicates that there is an overload, the reverse data is transmitted in consideration of scheduling allocation information of the neighboring base station.

Another preferred embodiment of the present invention devised to achieve the above objects is a method for a mobile station to allocate a reverse radio resource in a mobile communication system for transmitting reverse packet data, wherein the wireless network controller is connected to the mobile station. Transmitting interval information for controlling reverse overloading of a base station of a neighboring base station and a neighboring base station to communicate with the base station, and comparing a transmission rate of the reverse data transmitted from the mobile terminal and a scheduling allocation rate by the base station; And detecting radioactive presence of the neighboring base station, and allocating radio resources for transmitting reverse data in consideration of scheduling allocation information of the neighboring base station during the interval information.

Another preferred embodiment of the present invention devised to achieve the above objects is a mobile device comprising a base station located in a soft handover area to control its own cell and a mobile terminal communicating with an adjacent base station adjacent to the base station. A method of transmitting reverse data by a mobile terminal in a communication system, the method comprising: receiving, by a base station from a wireless network controller, interval information indicating that an overload of the adjacent base station is valid; and reverse data transmitted from the mobile terminal. And comparing the transmission rate of the transmission rate with the transmission rate of the scheduling allocation of the base station to detect the presence of an overload of the neighboring base station, and assigning a reverse data rate smaller than before during the interval information.

Another preferred embodiment of the present invention, which is invented to achieve the above objects, is a method in which a mobile station allocates a reverse radio resource in a mobile communication system for transmitting reverse packet data, wherein the wireless network controller comprises a plurality of mobile terminals. Setting the maximum transmission period as the length information of the overload bits which are commonly used in consideration of the transmission time intervals of the mobile stations, transmitting the length information of the set overload bits to the mobile terminals, and each of the mobile terminals. And changing the reception length and the effective section length of the overloaded bit according to the received length information of the overloaded bit.

Another preferred embodiment of the present invention, which is invented to achieve the above objects, is a method in which a mobile station allocates a reverse radio resource in a mobile communication system for transmitting reverse packet data, wherein the wireless network controller comprises a plurality of mobile terminals. Setting the maximum transmission period as the length information of the overload bits which are commonly used in consideration of the transmission time periods of the plurality of transmission periods, and transmitting the set information about the length of the overload bit to the base station where the plurality of mobile terminals are located; And a base station changing the transmission length of the overloaded bit according to the received length information of the overloaded bit.

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 provides an uplink scheduling method of a mobile terminal located in a soft handover area in providing an enhanced uplink packet data service.

The present invention is to reduce the forward signaling information according to the transmission format associated with the transmission of the reverse packet data, and to provide an optimal scheduling for efficiently using the reverse radio resources.

In other words, the present invention provides a mobile station located in a soft handover area, a scheduling base station (hereinafter referred to as an "optimal base station") and a mobile station for scheduling the mobile station and other mobile stations for reverse packet data transmission. A mobile terminal having a neighboring base station (hereinafter referred to as "non-optimal base station") which is included in an active set but is not an optimal base station, is located in the soft handover region, and the scheduling assignment information of the optimal base station is determined by the mobile terminal. Provides scheduling method according to reverse packet data transmission by receiving scheduling allocation information of non-optimal scheduling.

A mobile terminal in the soft handover area receives signaling related scheduling from an optimal base station and at least one non-optimal base station. At this time, the scheduling method of the optimal base station and the non-optimal base station for the mobile terminal is different. That is, the optimal base station performs scheduling for the mobile terminal located in the soft handover area using signaling allocated exclusively, while the non-optimal base station performs scheduling using common signaling. That is, the optimal base station transmits the scheduling information through the dedicated channel in order to satisfy the reliability, that is, the non-optimal base station transmits the scheduling information through the common channel. The scheduling operation of the optimal base station and the non-optimal base station mentioned above will be described in more detail below.

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

Referring to FIG. 5, mobile terminals 504 and 505 are located in the soft handover area. Here, the mobile terminal 504 manages an active set that includes the base stations 501 and 502, of which the base station 501 is an optimal base station of the mobile terminal 504. On the other hand, mobile terminal 505 manages an active set comprising base stations 502 and 503, of which base station 503 is the optimal base station of mobile terminal 505.

In this case, the base stations 501 to 503 perform scheduling using the state information of the mobile terminals 504 and 505. Accordingly, the mobile terminals 504 and 505 transmit their state information through the reverse link. In general, the state information of a mobile terminal is information that is periodically transmitted without considering reverse packet data, and an enhanced dedicated control channel (physical channel for transmitting control information of an E-DCH) when reverse packet data exists. E-DPCCH ') may be included and transmitted. That is, information transmitted regardless of data transmission through an enhanced dedicated data channel (physical channel for transmitting data through E-DCH, hereinafter referred to as 'E-DPDCH') and reverse packet data through E-DPDCH There is information transmitted only when there is transmission.

Here, information transmitted without considering the reverse packet data includes buffer status information and transmission power information, and the information can be transmitted through a physical channel. Alternatively, the information may be transmitted to the base station using a MAC-e signaling method, which is a method included in the MAC information (MAC-e) of the E-DCH and transmitted.

On the other hand, in consideration of reverse packet data, that is, when data is transmitted through the E-DPDCH, the information transmitted in the E-DPCCH may include a rate request bit. In addition, the information transmitted in the E-DPCCH may include a transport format indicator indicating a format of data currently included in the E-DPDCH, a retransmission sequence number, and a quality of service (QoS). May be referred to as a power boost).

In this case, the bit rate request bit may consist of 1 bit or more bits, and the mobile station requests a bit rate for data to be transmitted next using the bit rate request bit. For example, when a bit rate request bit of 1 bit is used, when the bit rate request bit is set to 1, it means a high bit rate according to transmission of reverse data. On the other hand, if the bit rate request bit is set to 0, it indicates that a higher bit rate is not required according to transmission of reverse data. That is, if the rate request bit is set to 'UP', it means that the scheduler of the base station allocates a higher data rate for the next E-DCH transmission.If the rate request bit is not set to 'UP', You will be told that you are satisfied with the data rate you are transmitting.

Accordingly, the optimal base stations 501 and 503 respectively schedule the mobile stations 504 and 505 using dedicated signals, and the non-optimal base station 502 schedules the mobile stations 504 and 505 using a common signal. To provide. In more detail, the non-optimal base station 502 informs the mobile terminals 504 and 505 of an overload of the reverse resource when the reverse resource situation of the cells they manage is not good. Will. That is, the mobile terminal 504, 505, which has set itself 502 as the non-optimal base station, transmits a command to lower the rate of reverse data to improve the situation of reverse resources.

The optimal base station 501 of the mobile terminal 504 transmits dedicated scheduling assignment information 506 to the mobile terminal 504, and the optimal base station 503 of the mobile terminal 505 also transmits to the mobile terminal 505. Dedicated scheduling assignment information 507 is transmitted. On the other hand, the non-optimal base station 502 performs scheduling using the common scheduling assignment information 508 for the mobile terminal 504 and the mobile terminal 505. That is, the base station 502 forwards common scheduling assignment information 508 forward for the mobile terminals 504 and 505 included in the active set but configured as non-optimal base stations. The common scheduling assignment information 508 indicates a change in the reverse link for both of the mobile terminals 504 and 505. Accordingly, mobile terminals 504 and 505 receive the common scheduling assignment information 508 transmitted from the base station 502 and use it to determine the transmission format of the E-DCH.

As described above, the mobile terminals 504 and 505 located in the soft handover area inform their plurality of base stations 501 to 503 of the active set by using reverse E-DPCCH or MAC-e signaling. The base stations 501 to 503 schedule using the state information of the mobile terminal. In this case, the mobile terminal 504 combines scheduling assignment information received exclusively from the optimal base station 501 and scheduling assignment information commonly received from the non-optimal base station 502 to transmit the E-DCH. Determine.

Hereinafter, the operation of the reverse data transmission of the mobile terminal through the following embodiments.

First embodiment

As described above, the mobile station receives dedicated scheduling assignments delivered from the optimal base station and overloaded bits from the non-optimal base station. At this time, if the overload bit from the non-optimal base station is set to '0', the terminal follows the scheduling allocation information from the optimal base station. However, if the overload bit from the non-optimal base station is set to '1', the operation of the mobile terminal is different.

Therefore, in the first embodiment of the present invention, the mobile station schedules transmission of the E-DCH using information indicating the valid period of the overloaded bit received from the RNC from the time point at which the overloaded bit is set from the non-optimal base station. That is, the mobile terminal receiving the overload bit from the non-optimal base station performs a distinct operation in consideration of the overload of the non-optimal base station instead of operating according to scheduling allocation information transmitted from the optimal base station, or to the base stations. The bit rate request bit according to the transmission of the E-DCH is operated with information other than "UP".

6 is a diagram illustrating signaling for transmitting and receiving valid interval information between an RNC and a UE according to the first embodiment of the present invention.

Referring to FIG. 6, the RNC 603 transmits valid section information 604 indicating the valid time of the overload bit set from the non-optimal base station to the mobile terminal 601. That is, the RNC 603 detects that the overload bit set from any non-optimal base station present in the active set of the mobile station 601 sets time information for the mobile terminal to perform the limited operation according to the overload bit. It is delivered to the mobile terminal 601.

In this case, the RNC 603 transmits the validity duration information to the mobile station 601 through RRC signaling. In addition, the mobile terminal 601 is a mobile terminal located in a soft handover region, and it can be seen that the valid section information is information on the set bit bit valid section of the non-optimal base station present in the active set. In addition, the validity duration information may be set differently according to the mobile terminal, or may be set differently according to the non-optimal base station. Or varies according to the quality of service (QoS) of the reverse data, the currently set transmission rate, or the state information of the mobile terminal.

As described above, the mobile station that recognizes the valid interval information of the overload bit set from any non-optimal base station through the RNC 603 does not transmit the reverse data according to the optimal transmission rate during the determined valid period, but performs limited operation. Will be performed. This will be described with reference to FIG. 7.

7 is a flowchart illustrating an operation of transmitting reverse data of a mobile station having received valid section information according to a first embodiment of the present invention.

Referring to FIG. 7, step 701 shows an initial state of a mobile terminal located in a soft handover area. In step 702, the mobile station located in the soft handover area receives the overload valid period information of the non-optimal base station from the RNC using RRC.

In step 703, the mobile station receives dedicated scheduling assignment information from an optimal base station and common scheduling assignment information at a non-optimal base station. In this case, the scheduling information is received from the optimal base station according to the reverse packet, and the common overload bit is received from the non-optimal base station.

In step 704, the mobile terminal determines whether the common overload bit received from the non-optimal base station is set to '1'. If it is confirmed in step 704 that the overload bit is set to 1, the process proceeds to step 705 and sets an arbitrary timer T as overload bit valid interval information received from the RNC. Here, the overload bit valid period indicates a TTI having a predetermined length and is a section for making the reverse resource of the non-optimal base station redundant during the set TTI. On the other hand, if the common overload bit is not set to '1', that is, if there is no overload at the non-optimal base station, the process proceeds to step 706.

In step 706, the mobile terminal determines whether the timer is greater than zero. That is, when the set valid duration information is greater than zero, the timer is shortened and the E-DCH is transmitted using the scheduling information predefined in step 709. In this case, the transmission rate in the E-DCH configuration is set to a rate that is one step smaller than before, or the transmission rate is selected so that the resource of the non-optimal base station no longer occupies. In step 709, the E-DCH configuration operation of the mobile terminal may be set in such a manner that the non-optimal base station recognizes that the reverse resource is overloaded so that the portion occupying the reverse resource in the non-optimal base station is not large.

In addition, in step 709, the mobile station transmits the E-DPCCH together with the control information of the E-DCH. The rate request information included in the mobile station is set to a value other than "UP". That is, the other state information is ignored and the rate request information is set to a value other than "UP". Setting the rate request information to a value other than "UP" may be defined equally to all mobile terminals, or may be set according to the priority of the mobile terminals or according to the setting of the RNC. In addition, the process of transmitting the state information of the mobile station may be arbitrarily limited using MAC-e signaling. That is, when the MAC-e signaling is used, the optimal base station allocates more resources to the mobile station, but the mobile station fails to use the resources, thereby degrading the system performance. A method of limiting e signaling may also be used.

On the contrary, if the operation is completed during the valid period in which the timer is set in step 706, the process proceeds to step 710 to transmit the E-DCH according to the scheduling assignment information of the optimal base station. That is, in step 710, the mobile terminal ignores the non-optimal base station in setting up the E-DCH and configures only the scheduling allocation information received from the optimal base station. Also in setting the rate request information of the E-DPCCH, arbitrary rate request information can be set according to the mobile terminal state.

As described above, in the first embodiment, the non-optimal base station in the active set transmits its overload situation to the mobile terminal located in the soft handover area using an overload bit. That is, the overload bit is allocated as scheduling information. On the other hand, the optimal base station allocates uplink resources to each of the mobile stations using an independent dedicated scheduling allocation method.

Accordingly, the mobile station receiving the overload bit from the non-optimal base station transmits the reverse data by selecting a data rate in consideration of the uplink resource of the non-optimal base station according to the valid interval information of the overload bit received from the RNC.

8 is a flowchart illustrating an operation of retransmitting reverse data by a mobile terminal having received valid section information according to the present invention.

In FIG. 8, when the mobile terminal transmits reverse data, a method for informing whether the data to be transmitted is initial transmission is proposed.

In this case, the mobile station located in the soft handover area in FIG. 8 receives scheduling allocation information using an overload bit from a non-optimal base station, while receiving dedicated scheduling allocation information independent from an optimal base station. Allocate

Accordingly, when the mobile terminal detects that the overload bit from the non-optimal base station is not set in allocating reverse resources, the mobile station operates according to the scheduling allocation information from the optimal base station. In other words, the mobile station that detects a situation in which the non-optimal base station is overconfigured sets the rate request bit to a value other than "UP", and sets scheduling information allocated from the optimal base station in the initial transmission occurring in the near future. Ignore it and perform other arbitrarily defined actions.

Referring to FIG. 8, step 801 shows an initial state of a mobile terminal located in a soft handover area. In step 802, the mobile terminal located in the soft handover area receives corresponding scheduling assignment information from the optimal base station and the non-optimal base station in the active set. In this case, dedicated scheduling allocation information is received from the optimal base station, and a common overload bit is received from the non-optimal base station. In step 803, the mobile terminal determines whether the common overload bit is set to '1'. That is, if it detects that the reverse resource of the non-optimal base station is excessive, in step 804, the rate request bit of the E-DPCCH is limited not to specify "UP" in transmission of the next E-DCH. That is, the optimal base station limits resource allocation to the mobile station in scheduling of the next E-DCH to make the situation of reverse resources of the non-optimal base station more relaxed. On the other hand, if the overload bit is not set to '1' in step 803, the process proceeds to step 806.

In step 805, the mobile terminal sets an initial transmission tag to indicate whether the data to be transmitted currently is initial data. In step 806, the mobile station determines whether the initial transmission tag is '1' while the data is initial transmission of the E-DCH. If the condition of step 806 is satisfied, the mobile station ignores the scheduling information allocated by the optimal base station in the initial E-DCH configuration, and predefined scheduling allocation only when the overload bit of the non-optimal base station is set to '1'. Based on the method, the E-DCH is set and transmitted. Here, the predefined method performs an operation so that the resources of the non-optimal base station no longer occupy, such as setting a data rate one step smaller than before or maintaining data.

On the other hand, if the condition of step 806 is not satisfied, the process proceeds to step 808 and the initial transmission tag is set to '0'. In step 809, the mobile station ignores the non-optimal base station and configures the E-DCH using only scheduling assignment information received from the optimal base station. Also in setting the rate request information of the E-DPCCH, arbitrary rate request information can be set according to the mobile terminal state.

Second embodiment

First, in the following second embodiment, the mobile station is located in the soft handover area. At this time, the non-optimal base station in the active set informs the terminal of its overload situation by using an overload bit, instead of scheduling. do. On the other hand, the optimal base station transmits independent dedicated scheduling allocation information to the mobile terminal to allow the mobile station to allocate reverse resources. In this case, the operation of the mobile terminal is similar to that of FIG. 7 or 8 described above.

That is, the mobile terminal receives dedicated scheduling assignments delivered from the optimal base station and overloaded bits from the non-optimal base station. At this time, if the overload bit from the non-optimal base station is set to '0', the mobile station allocates a reverse resource according to scheduling allocation information from the optimal base station. On the other hand, if the overload bit from the non-optimal base station is set, that is, set to '1', the operation of the mobile terminal is limited.

In other words, the mobile terminal that detects the situation in which the overload bit is set sets the rate request bit to a value other than "UP", and is different from the scheduling information allocated by the optimal scheduling in the initial transmission occurring in the near future. Perform the action. In this case, the randomly defined operations include a method of using a data rate one step lower than the scheduling information allocated by optimal scheduling, and a method of using a data rate one step lower than the previous data rate.

In this regard, in the following second embodiment, the RNC delivers overload bit valid section information of the non-optimal base station of the active set of the mobile terminal to the optimal base station, and the optimal base station is the mobile terminal in soft handover. Use the E-DCH at a rate smaller than the scheduling information allocated by the base station. That is, the mobile terminal is determined to be a mobile terminal that has received an overload bit, and is scheduled in consideration of a certain disadvantage in scheduling the mobile terminal during the overload bit valid period.

9 is a diagram illustrating signaling for transmitting and receiving valid section information between an RNC and a base station according to a second embodiment of the present invention.

Referring to FIG. 9, the RNC 902 signals overload valid period information of the non-optimal base station to the optimal base station. The RNC 902 transmits valid interval information 903 to the optimal base station 901, which is transmitted through NBAP signaling. In this case, when another RNC exists between the RNC 902 and the base station 901, RNSAP signaling is also accompanied.

Here, the overload bit valid period may be set to a different value according to the mobile terminal, may be set to a different value according to the non-optimal base station, or set in consideration of QoS, current transmission rate, and status information of the mobile terminal. Can be. In addition, the signaling may be performed while the mobile terminal includes the non-optimal base station as an active combination, and the signaling process may be performed even when the overloaded bit valid period information is changed. Depending on other situations, the signaling may be performed.

10 is a flowchart illustrating an operation of a base station receiving valid section information according to the present invention. Here, the base station is an optimal base station.

Referring to FIG. 10, in step 1001, the optimum base station receives overload bit valid interval information of mobile terminals belonging to the base station and located in a soft handover region from the RNC. In step 1002, the optimal base station transmits scheduling assignment information to the mobile terminal and receives E-DCH data from the mobile terminal in step 1003.

In step 1004, the optimal base station compares the data rate allocated to the mobile terminal with the data rate received from the mobile terminal. At this time, if the received data rate is smaller than the allocated data rate, the process proceeds to step 1005 and the mobile station is considered to have received the overload bit from the non-optimal base station. That is, it is determined that reverse resources of the non-optimal base station adjacent to the optimal base station are overloaded so that the setting of the overload bit is instructed.

In step 1006, the optimal base station sets a timer using the overloaded bit valid period information received from the RNC. In step 1007, the optimal base station determines whether the timer is greater than zero. In other words, when the set valid period information is greater than zero, the timer is decremented by one step in step 1007. In step 1009, the optimal base station assumes that the mobile terminal is instructed to overload control with respect to reverse resources from the non-optimal base station and allocates less scheduling information instead of allocating optimized scheduling allocation information. That is, it allocates somewhat less resources than other mobile terminals. On the other hand, if the timer is less than '0' in step 1007, the optimized scheduling information is allocated. That is, the mobile terminal guarantees maximum reverse resources.

Third embodiment

In the following third embodiment, a mobile station is located in a soft handover area, where a non-optimal base station in an active set replaces scheduling by notifying the mobile station of its overload situation using an overload bit. . In addition, in the third embodiment, when the transmission time intervals (hereinafter, referred to as 'TTI') of the plurality of mobile terminals located in the soft handover are different from each other, the scheduling operation of the mobile terminal will be described.

In this case, the validity of the overload bit is more effective when the valid period of the overload bit applied to each of the plurality of mobile terminals receiving the overload bit is set to be the same as much as possible.

Therefore, when the mobile terminals using the 2ms TTI and the terminals using the 10ms TTI are simultaneously located in the soft handover area, there is a need for a method of setting the valid period of the overload bit to be the same.

For example, when only mobile terminals using a 2 ms TTI are located in the soft handover area, that is, when there is no mobile terminal using a 10 ms TTI, the overload bit is set in units of 2 ms. In addition, the effective period of the overload bit is also set in units of 2ms.

On the other hand, when the mobile stations using the 2ms TTI and the mobile stations using the 10ms TTI coexist, the 10ms TTI and the 2ms TTI mobile terminals are commonly received the overload bit from the non-optimal base station. . In this case, since the timing of the overload bit transmission is different between the mobile terminals using the 2ms TTI and the mobile terminals using the 10ms TTI, a timing for receiving the overload bit should be newly set. In addition, the valid period of the overload bit must also be newly set.

In other words, in the third embodiment, when the 2ms TTI mobile terminal does not exist together with the 10ms TTI mobile terminal in the soft handover area, that is, when there are only 2ms TTI mobile terminals, a 2ms long overload bit and 2ms are present. Set valid period of overload bit of TTI. That is, the length of the overload bit itself has a length of 2ms, and the effective period of the overload bit is set to an integer multiple of 2ms. At this time, the valid period of the overload bit can be transmitted as in the first and second embodiments.

On the other hand, in the case of a 2 ms TTI mobile terminal with a 10 ms TTI mobile terminal in the soft handover area, the reception of the overload bits transmitted from the non-optimal base station and the effective period are the same as those of the 10 ms TTI. It suggests how to set it up.

That is, in the case where the 2ms TTI mobile terminal and the 10ms TTI mobile terminal exist together, the length of the overload bit itself is set to 10ms long in order to apply to both the mobile terminal of the 2ms TTI and the mobile terminal of 10ms TTI in common. do. The valid period of the overload bit is also set to an integer multiple of 10 ms.

Here, whether the 2ms TTI mobile terminal receives a 2ms long overload bit to set the overload bit validity interval of 2ms length unit, or receives a 10ms long overload bit to configure the overload bit validity period of 10ms length unit is various. It can be decided in a way.

The first method does not consider a mobile terminal of 2ms TTI or a mobile terminal of 10ms TTI and always transmits and receives assuming that the overload bit is 10ms long. Therefore, the valid period of the overload bit may also be defined in units of 10ms. That is, in the first method, even if only a mobile terminal of 2ms TTI exists in the soft handover area, the use of the overload bit is operated with a length of 10ms.

The second method is a method in which the RNC determines the TTI of the mobile terminals included in the soft handover area and transmits length information of the overloaded bits to the mobile stations and the base station where the mobile terminals are located.

FIG. 11 is a diagram illustrating signaling for transmitting and receiving valid section information to mobile stations having different TTIs according to the third embodiment of the present invention.

Referring to FIG. 11, the mobile terminal 1101 and the base station 1102 receive the information on the length of the overload bit through signaling from the RNC 1103 and based on the information received from the RNC 1103. Perform the transmission and reception of. Then, the valid section setting of the overload bit is changed.

First, in step 1104, the mobile terminal 1101 transmits its TTI information 1104 to the RNC 1103 through an RRC message.

In step 1105, the RNC 1103 which receives the TTI information of the mobile station 1101 which belongs to the base station 1102 and is located in the soft handover area, transmits the TTI information to the plurality of mobile terminals in common. Set the length of the overload bit you want. Here, the length of the overloaded bit is information including a transmission length of the overloaded bit (that is, a unit for transmitting the overloaded bit) and a valid period of the overloaded bit. This is because the valid period of the overloaded bit is set to an integer multiple corresponding to the set transmission length of the overloaded bit.

In step 1106, the RNC 1103 transmits the length information 1106 of the set overload bit to the base station 1102 using NBAP signaling.

Therefore, in step 1108, the base station 1102 changes the transmission length of the overloaded bits in response to the set length information of the overloaded bits. Here, the base station 1102 may be all base stations included in an active set of the mobile terminal 1101.

In addition, in step 1107, the RNC 1103 transmits the length information 1106 of the set overload bit to the mobile terminal 1101 using RRC signaling.

In step 1109, the mobile terminal 1101 changes the reception length of the overloaded bit in response to the set length information of the overloaded bit. This has the same length as the overload bit transmission length of the base station 1102. In operation 1110, the mobile terminal 1101 also changes the valid period of the overload bit.

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 has the advantage of increasing the efficiency of the entire mobile communication system by allocating reverse resources in consideration of common scheduling information of the non-optimal base station in the mobile station located in the soft handover area.

Claims (20)

A method for allocating reverse radio resources by a mobile station in a mobile communication system transmitting reverse packet data, Transmitting, by the radio network controller, interval information indicating the validity of the overload bit of the neighboring base station adjacent to the base station of the own cell communicating with the mobile station to the mobile station; And the mobile terminal does not transmit a rate request bit for a predetermined interval using the interval information. A method for transmitting reverse data by a mobile terminal in a mobile communication system including a base station located in a soft handover area to control its own cell and a mobile station communicating with an adjacent base station adjacent to the base station; Receiving, by the mobile terminal, interval information indicating validity of an overload bit of an adjacent base station from a wireless network controller; Receiving scheduling allocation information indicating whether there is an overload from the neighboring base station; And the reverse direction data is transmitted in consideration of the scheduling allocation information of the neighboring base station without considering the scheduling allocation information received from the base station of the own cell during the interval information. The method of claim 2, The mobile terminal receives scheduling assignment information from a base station of the own cell through a dedicated channel. The method of claim 2, And the mobile station receives scheduling allocation information indicating whether there is an overload from a common channel from the neighboring base station. The method of claim 2, The mobile terminal does not transmit a rate request bit due to transmitting reverse data during the interval information. The method of claim 2, The mobile terminal does not transmit the state information of the mobile terminal during the section information. A method for transmitting reverse data by a mobile terminal in a mobile communication system including a base station located in a soft handover area to control its own cell and a mobile station communicating with an adjacent base station adjacent to the base station; Receiving, by the mobile terminal, scheduling allocation information from the base station of the own cell and the adjacent base station, respectively; And if the scheduling allocation information transmitted from the neighboring base station is information indicating that there is an overload, the reverse data is transmitted in consideration of the scheduling allocation information of the neighboring base station. The method of claim 7, wherein The mobile terminal, when the data is initially transmitted, includes the identifier indicating that the initial transmission in the reverse data in consideration of the scheduling assignment information of the neighboring base station. A method for allocating a reverse radio resource by a mobile station in a mobile communication system transmitting reverse packet data, Transmitting, by a wireless network controller, interval information for controlling reverse overload of a base station of a neighboring base station and a neighboring base station of a mobile station communicating with the mobile station to the base station; Comparing the transmission rate of the reverse data transmitted from the mobile station with the transmission rate allocated by the base station to detect whether there is an overload of the neighboring base station; And allocating radio resources for transmitting reverse data in consideration of scheduling allocation information of the neighboring base station during the interval information. A method for transmitting reverse data by a mobile terminal in a mobile communication system including a base station located in a soft handover area to control its own cell and a mobile station communicating with an adjacent base station adjacent to the base station; Receiving, by the base station, interval information indicating that the overload of the adjacent base station is valid from a radio network controller; Comparing the transmission rate of the reverse data transmitted from the mobile terminal with the scheduling allocation rate of the base station to detect whether there is an overload of the neighboring base station; And allocating a reverse data rate smaller than before during the interval information. A method for allocating reverse radio resources by a mobile station in a mobile communication system transmitting reverse packet data, Setting, by the radio network controller, the maximum transmission period in consideration of the transmission time intervals of a plurality of mobile terminals as length information of the overload bits used in common; Transmitting length information of the set overload bit to the mobile terminals; And changing, by each mobile terminal, the reception length and the effective interval length of the overloaded bit according to the received length information of the overloaded bit. The method of claim 11, The effective interval length is set to an integer multiple of the reception length of the set overload bit. The method of claim 11, The wireless network controller further comprises the step of receiving the transmission time interval information from a radio resource control (Radio Resource control) message from the mobile terminal. The method of claim 11, The wireless network controller further comprises the step of transmitting the set length information of the overload bit to the mobile terminal through a Radio Resource Control (Radio Resource control) message. A method for allocating reverse radio resources by a mobile station in a mobile communication system transmitting reverse packet data, Setting, by the radio network controller, the maximum transmission period in consideration of the transmission time intervals of a plurality of mobile terminals as length information of the overload bits used in common; Transmitting the length information of the set overload bit to a base station in which the plurality of mobile terminals are located; And changing, by the base station, a transmission length of the overloaded bit according to the received length information of the overloaded bit. The method of claim 15, The wireless network controller further comprises the step of transmitting the length information of the set overload bit to the base station through a Node B Application Part (Node B Application Part) message. The method of claim 15, The base station further comprises the step of transmitting to the mobile terminal scheduling allocation information indicating whether there is an overload according to the transmission length of the changed overload bit. The method of claim 15, The base station sets the transmission length of the overload bit to 10ms. The method of claim 11, The mobile terminal sets the reception length of the overload bit to 10ms. The method of claim 19, The mobile terminal is characterized in that for setting the valid period of the overload bit to an integer multiple of the 10ms.

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