KR20060054663A - Method for transmitting/receiving packet size signaling method of up-link packet data service in mobile telecommunication system - Google Patents

Abstract

The present invention relates to a mobile communication system for transmitting packet data through an uplink, and more particularly, to a method for transmitting and receiving packet size information between a user terminal and a base station. In uplink, the size of a packet transmitted by a terminal during one transmission interval is transmitted to a base station by being contained in information called an E-TFCI. There are various ways to define E-TFCI and packet size. In some cases, appropriate method should be used.

Accordingly, the present invention provides a method for determining an E-TFCI signal system to be used for a specific EDCH call by a base station or a base station controller and informing the terminal of the E-TFCI signal system. This makes it possible to use the most appropriate E-TFCI signaling system for each EDCH call and improve communication efficiency.

WCDMA, UPLINK PACKET DATA SERVICE, E-DCH, EUDCH, MAC-e, E-TFCI, E-TFCS

Description

Method for transmitting / receiving a packet size signal scheme of an uplink packet data service in a mobile communication system             

1A is a diagram illustrating a change in uplink radio resources of a base station when base station control scheduling is not used.

1B is a diagram illustrating a change in uplink radio resources of a base station when using base station control scheduling.

2 is a diagram illustrating a user terminal and a base station for performing uplink packet transmission.

3 is a diagram illustrating information transmitted and received between a user terminal and a base station to perform uplink packet transmission.

4 is a diagram illustrating a process of transmitting a packet size signal system to a terminal after determining the packet size signal system according to an exemplary embodiment of the present invention.

5 is a diagram illustrating a process of a base station determining a packet size signal system and transmitting the same to a terminal according to a preferred embodiment of the present invention.

6 is a diagram illustrating a process of a base station controller determining a packet size signal system and transmitting the packet size signal system to a base station and a terminal according to a preferred embodiment of the present invention.

The present invention relates to a mobile communication system for transmitting packet data through uplink. In particular, the present invention relates to a method of using the selected packet size information system after appropriately selecting an information system indicating the size of uplink packet data according to a situation. It is about.

Asynchronous Wideband Code Division Multiple Access (WCDMA) The communication system uses an Enhanced Uplink Dedicated CHannel (hereinafter referred to as "E-DCH" or "EUDCH"). The EUDCH is a channel proposed to improve the performance of packet transmission in reverse communication in an asynchronous code division multiple access communication system.

A mobile communication system supporting EUDCH maximizes the efficiency of uplink transmission using Node B-controlled scheduling and Hybrid Automatic Retransmission Request (HARQ). In the base station scheduling scheme, the Node B receives and reports channel conditions and buffer conditions of user equipments (UEs), and controls backward transmission of the UEs based on the received information. The base station allows efficient use of limited uplink transmission resources by allowing large amounts of data transmission to UEs in good channel conditions and minimizing the amount of data transmission for UEs in poor channel conditions. The HARQ technique increases the transmission success rate compared to the transmission output by executing HARQ between the UE and the base station. Through the HARQ technique, the base station performs soft combining with the retransmitted data block without discarding the data block in which an error occurs during transmission, thereby increasing the probability of success of receiving the data block.

In the uplink, orthogonality is not maintained between signals transmitted by a plurality of user terminals (UEs), thus acting as interference signals. Therefore, as the number of uplink signals received by the base station increases, the amount of interference signals for the uplink signals transmitted by a specific UE also increases. Therefore, as the amount of the interference signal for the uplink signal transmitted by a specific UE increases, the reception performance of the base station is degraded. This limits the amount of uplink signals that the base station can receive while guaranteeing overall reception performance. The radio resource of the base station is represented by Equation 1 below.

RoT = Io / No

Io is the total received broadband power spectral density of the base station, and No represents the thermal noise power spectral density of the base station. Accordingly, the ROT becomes a radio resource that the base station can allocate for the EUDCH packet data service on the uplink.

1A and 1B show a change in uplink radio resources that can be allocated by a base station.

As shown in FIG. 1A and FIG. 1B, the uplink radio resource allocated by the base station is represented by the sum of the inter-cell interference (ICI, inter-cell interference), voice traffic, and EUDCH packet traffic. Can be.

FIG. 1A illustrates a change in the total ROT when Node B scheduling is not used. Since scheduling is not performed on the EUDCH packet traffic, when a plurality of UEs simultaneously transmit the packet data using a high data rate, the total ROT may be higher than a target ROT. In this case, the reception performance of the uplink signal is degraded.

1B shows the change in the total ROT when using Node B scheduling. When using the Node B scheduling, Node B prevents the plurality of UEs from simultaneously transmitting the packet data using a high data rate. That is, the base station scheduling prevents the total ROT from increasing above the target ROT by allowing other UEs to have a lower data rate when they allow a higher data rate for a particular UE.

The higher the data rate of a particular UE, the greater the received power received by the base station from the UE. Therefore, the ROT of the UE occupies a large part of the total ROT. On the other hand, when the data rate of the UE decreases, the reception power received by the base station from the UE decreases. Therefore, the ROT of the UE occupies a small part of the total ROT. The base station performs base station scheduling for the EUDCH packet data in consideration of the relationship between the data rate and radio resources and the data rate requested by the UE.

The base station notifies whether EUDCH data transmission is possible for each UE by using request data rate or channel state information of UEs using the EUDCH or performs base station scheduling to adjust the EUDCH data rate. The base station scheduling may be regarded as an operation in which the Node B distributes RoT to each terminal based on channel conditions and buffer conditions of terminals performing EUDCH communication.

2 illustrates a user terminal and a base station for performing uplink packet transmission.

According to FIG. 2, the UEs 210, 212, 214, and 216 are transmitting uplink packet data at different transmit powers of reverse channels according to the distance from the base station 200. The UE 210 farthest from the base station 200 transmits packet data at the transmit power 220 of the highest reverse channel, and the UE 214 closest from the base station 200 has the lowest reverse direction. The packet data is transmitted at the transmit power 224 of the channel. The base station 200 may schedule the data to be inversely proportional to the strength of the transmit power of the reverse channel in order to improve the performance of the mobile communication system while reducing the ICI for other cells while maintaining the total ROT. Therefore, the base station 200 allocates a small transmission resource to the UE having the highest transmission power of the reverse channel, and allocates many transmission resources to the UE having the lowest transmission power of the reverse channel to efficiently maintain the total ROT. .                         

3 illustrates an operation in which a UE is allocated a transmission resource for EUDCH packet data transmission from a base station and transmits the packet data using the allocated transmission resource.

Referring to FIG. 3, in step 310, an EUDCH is set between the base station 300 and the UE 302. Step 310 includes a process of transmitting and receiving messages through a dedicated transport channel. The UE 302 having configured the EUDCH transmits information on necessary transmission resources and information on uplink channel conditions to the base station 300 in step 312. The information includes uplink transmission power transmitted by the UE 302, transmission power margin of the UE 303, buffer status information of the terminal, and the like.

The base station 300 receiving the information estimates a forward channel situation by comparing the transmission power of the uplink channel with the actual measured reception power. That is, if the difference between the uplink transmit power and the uplink receive power is small, the reverse channel situation is good. If the difference between the transmit power and the receive power is large, the reverse channel situation is poor. When the UE transmits a transmission power margin to estimate an uplink channel condition, the base station 300 estimates the uplink transmission power by subtracting the transmission power margin from the maximum possible transmission power of a known UE. . The base station 300 determines available transmission resources for the uplink packet channel of the UE by using the estimated channel condition of the UE and buffer status information of the UE 302.

The determined transmission resource is notified to the UE 302 in step 314. In this case, the transmission resource may be a size of data that can be transmitted, that is, a transmission rate, or a transmission output that can be used. The UE 302 determines the size of packet data to be transmitted to the informed transmission resource, and transmits the determined size data to the Node B 300 in step 316. In this case, one unit of the packet data transmitted through the EUDCH is referred to as a medium access control-enhanced protocol data unit (MAC-e PDU), and the terminal transmits the MAC-e PDU to determine the size of the MAC-e PDU. Send the information you indicate together. The size information is called an EUDCH-Transport Format Combination (E-TFC) and is usually transmitted in a physical channel signal called an EUDCH-Transport Format Combination Identifier (E-TFCI) having a size of 6 bits.

However, only 64 pieces of information can be represented by 6-bit E-TFCI. On the other hand, the maximum size of the MAC-e PDU is expected to reach 8600 bits in 2 msec transmission period and 20,000 bits in 10 msec transmission period. Using the 6-bit E-TFCI to represent the maximum size of 20000 bits is quite a burden. For example, in order to represent 20000 bits with 6-bit E-TFCI, a step size of 312 bits is required. This means that the size of the padding may reach up to 311 bits, and this size of padding may cause a serious degradation in transmission efficiency, especially in a section in which the size of the MAC-e PDU is small. For example, if any E-TFCI means 624 bits, and the size of the actual transmitted MAC-e PDU is 313 bits, 311 bits are filled with padding which is meaningless data and transmission efficiency is only 50%. Therefore, there is a need for a method of transmitting E-TFC and E-TFCI information that increases transmission efficiency by reducing the size of the padding. Hereinafter, the E-TFCI signaling system is called as including the relationship between the E-TFC and the E-TFCI, and the method of obtaining the E-TFC from the E-TFCI.

The E-TFCI signaling system that improves transmission efficiency includes one E-TFCI and E-TFC corresponding to one-to-one, and one E-TFCI and multiple E-TFCs to correspond one-to-many. The E-TFCI signaling schemes have advantages and disadvantages. For example, one E-TFCI and one E-TFC correspond to a one-to-one correspondence, which imposes a large processing load on Node B. It has the advantage that the amount is small. On the other hand, the one-to-many correspondence of one E-TFCI and multiple E-TFCs does not have the disadvantage of the processing load added to Node B, but has the disadvantage that the amount of control signals exchanged before call establishment is large. .

Accordingly, an object of the present invention for solving the above-mentioned problems of the prior art is to select and use an appropriate E-TFCI signaling system according to the type of call or the amount of processing load added to Node B in a mobile communication system supporting uplink. To provide a way to.

Another object of the present invention for solving the above-described problems of the prior art, in the mobile communication system supporting uplink, the base station selects an appropriate E-TFCI signal system according to the amount of processing load to communicate with the mobile terminal To provide a way to.

Another object of the present invention for solving the above-mentioned problems of the prior art is that, in a mobile communication system supporting uplink, an E-TFCI signal suitable for a base station controller according to the amount of processing load of the base station and the amount of packet data of the mobile station. The present invention provides a method for selecting a scheme and setting up a call according to the uplink.

The embodiment for achieving the object of the present invention is a method of transmitting packet data by the mobile terminal in the mobile communication system that transmits the always reverse packet data, the processing capacity available when the base station detects the packet data generation of the mobile terminal Considering a signal system for processing the reverse data in consideration of the above, and establishing a call for the enhanced reverse packet data according to the selected reverse data signal system and communicating with the mobile terminal. It is characterized by.

Another embodiment for achieving the object of the present invention is a method of transmitting packet data by a mobile terminal in a mobile communication system that transmits the always reverse packet data, when the base station controller detects the occurrence of packet data of the mobile station of the base station Variably selecting a signaling system for processing the enhanced reverse data in consideration of the available processing capacity, and transmitting a constant reverse packet data setting message including an identifier indicating the selected reverse data signaling system to a base station and a mobile station; And transmitting, by the base station and the mobile station, establishing a call according to the message, and performing always reversed packet data communication.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the present invention, the Node B and the terminal is provided with a plurality of E-TFCI signaling scheme, Node B or RNC proposes a method for notifying the terminal after determining the E-TFCI signaling scheme to be used for the EDCH call. This allows the use of the most appropriate E-TFCI signaling scheme, depending on the nature of the EDCH call or the amount of load added to Node B. Therefore, rather than using only one method as an E-TFCI signaling system, it is provided to select and use an appropriate E-TFCI signaling system according to the situation.

4 shows the general operation of the present invention.

The UE and Node B are equipped with n E-TFCI signaling schemes such as Method 1, Method 2, .., Method n. For example, the following three E-TFCI signaling schemes are provided in the UE and Node B.

E-TFCI Signaling System 1

64 E-TFCs are defined, and E-TFC and E-TFCI correspond one-to-one as shown in Table 1. The relationship between the E-TFCI and the E-TFC shown in Table 1 is previously stored by the UE and the Node B. Therefore, since E-TFCI and E-TFC correspond one-to-one, Node B can directly obtain E-TFC from E-TFCI.

<Table 1>

E-TFCI E-TFC (MAC-e PDU Size) E-TFC 0 353 E-TFC 1 689 E-TFC 2 1025 E-TFC 3 1361 ... ... E-TFC 60 20177 E-TFC 61 20513 E-TFC 62 20849 E-TFC 63 21185

In the signaling system, for example, E-TFCI called E-TFC 3 means a MAC-e PDU having a size of 1361 bits.

E-TFCI Signaling System 2

By mapping multiple E-TFCs to one E-TFCI, it has the effect of increasing the size of the E-TFCI field.

In the E-TFCI signaling scheme, for example, 256 E-TFCs and 64 E-TFCIs are defined, and four E-TFCs correspond to one E-TFCI. An example of the signaling scheme 2 is shown in Table 2.

<Table 2>

E-TFCI E-TFC (MAC-e PDU Size)  E-TFC 0 107 109 111 113 ... ...  E-TFC 63 18860 19257 19661 20047

As shown in Table 2, since one E-TFCI corresponds to a plurality of E-TFCs in Signaling System 2, Node B processes E-TFCs corresponding to the E-TFCI. The information in Table 2 is previously stored in the UE and the Node B.

E-TFCI Signaling System 3

The E-TFCI signaling scheme 3 is a method of minimizing padding that may occur due to limited capacity of a physical channel. How to decide.

That is, the RNC determines the relationship between the E-TFC and the E-TFCI when establishing an EDCH call, and transfers the information to the terminal and the base station.

As described above, since the E-TFCI signaling system 1 applies only one E-TFC to one E-TFCI, the processing load imposed on the Node B is small. On the other hand, since a small number of E-TFCs are defined, the transmission efficiency is low.

In addition, the E-TFCI signaling scheme 2 has a disadvantage in that the processing load imposed on the Node B is large because the Node B must apply several E-TFCs to one E-TFCI. On the other hand, since a large number of E-TFCs are defined, the transmission efficiency is high.

Therefore, it is preferable to select the E-TFCI signaling scheme 2 if the processing capacity of Node B is sufficient to handle the high processing load, and if the processing capacity of the Node B is insufficient and cannot handle the high processing load, It is preferable to select -TFCI signaling scheme 1.                     

In addition, the E-TFCI signaling system 3 has to set the E-TFCS every time a call is set, but has a disadvantage in that the size of the control signal to which the call setup signal is exchanged is large, but the padding can be completely removed.

When an EDCH call is established for an arbitrary terminal, the Node B or RNC selects an E-TFCI signaling system to be used for the EDCH call and notifies the terminal. For example, if a plurality of UEs perform EDCH communication through the Node B, and there is insufficient processing capacity available to the Node B, E-TFCI signaling system 1 or E-TFCI signaling system 3 is selected, and EDCH communication is performed. Since the number of terminals being used is small, if the available processing capacity is sufficient, E-TFCI signaling system 2 is selected.

When Node B selects the E-TFCI signaling scheme, the selected E-TFCI signaling scheme is notified to the terminal via the RNC.

When the RNC selects the E-TFCI signaling scheme, the selected E-TFCI signaling scheme is notified to the Node B and the UE, respectively.

Thereafter, the terminal and the base station use the selected E-TFCI signaling system when performing the EDCH call.

FIG. 5 illustrates a flow of control signals between the RNC and the UE and the Node B when the Node B selects the E-TFCI signaling scheme according to an embodiment of the present invention.

Referring to FIG. 5, the UE and the Node B are provided with an E-TFCI signaling scheme 1, an E-TFCI signaling scheme 2, and an E-TFCI signaling scheme 3 (705).

At any point in time, the RNC determines to establish an EDCH for the UE (710). This may be at the request of a terminal or may be due to the generation of data to be transmitted to the terminal.

The RNC determines EDCH configuration information and transmits the EDCH configuration information to the Node B through an EDCH configuration message (715). EDCH configuration information may include information related to HARQ.

The Node B receiving the EDCH configuration message configures the EDCH according to the EDCH configuration information. In operation 720, the E-TFCI signaling system to be applied to the terminal is determined. This can be done based on the processing power available to Node B. In other words, if the processing power available at this point is sufficient, E-TFCI signaling scheme 2 is selected. On the other hand, if there is not enough processing power available, choose E-TFCI signaling scheme 1 or 3.

The Node B includes the selected E-TFCI signaling scheme identifier in the EDCH establishment response message and transmits it to the RNC (725).

When the RNC receives the EDCH configuration response message, the RNC transmits an EDCH configuration message to the terminal in order to configure the EDCH in the terminal (730). The message includes EDCH configuration information. For example, EDCH configuration information includes information related to HARQ and channel information through which a rate grant is transmitted. The RNC transmits the E-TFCI signaling scheme identifier selected by Node B in the message.

When the terminal receives the EDCH setting message, the terminal sets the EDCH according to the information of the message and selects the E-TFCI signaling system.

Thereafter, the UE and the Node B perform EDCH communication according to the E-TFCI signaling scheme (735).

6 illustrates a control signal flow between the RNC, the UE, and the Node B when the RNC selects the E-TFCI signaling scheme according to another embodiment of the present invention.

Referring to FIG. 6, the UE and the Node B are provided with an E-TFCI signaling scheme 1, an E-TFCI signaling scheme 2, and an E-TFCI signaling scheme 3 (805).

At any point in time, the RNC determines to set the EDCH to the UE (810). This may be at the request of the terminal or may be due to the generation of data to be transmitted to the terminal. At this time, the RNC also decides the E-TFCI signaling system to be used for the EDCH in consideration of the following.

Node B processing power: If there is room in Node B processing power, use E-TFCI signaling scheme 2.

Nature of EDCH: If the service provided by EDCH is expected to transmit a large amount of data, E-TFCI signaling scheme 3 is used to reduce padding.

If the two conditions do not apply, E-TFCI signaling scheme 1 is used.

The RNC determines EDCH configuration information and transmits the E-TFCI signaling scheme identifier to the Node B through the EDCH configuration message together with the EDCH configuration information (815). EDCH configuration information may include information related to HARQ.

Upon receiving the EDCH configuration message, the Node B configures the EDCH according to the EDCH configuration information and transmits a response message (820).

When the RNC receives the EDCH configuration response message, the RNC transmits an EDCH configuration message to the terminal in order to configure the EDCH in the terminal (825). The message includes EDCH configuration information. For example, EDCH configuration information includes information related to HARQ and channel information through which a rate grant is transmitted. The RNC sends an E-TFCI signaling scheme identifier in the message.

When the terminal receives the EDCH setting message, the terminal sets the EDCH according to the information of the message and selects the E-TFCI signaling system.

Thereafter, the UE and the Node B perform EDCH communication according to the E-TFCI signaling system (830).

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 effect of increasing the transmission efficiency of the EDCH call by selecting the most appropriate E-TFCI signaling system for each EDCH call. That is, when the EDCH call is established, the transmission efficiency is guaranteed by selecting the E-TFCI signal system in consideration of the load of the base station and the amount of packet data of the mobile station.

Claims (12)

In the mobile communication system for transmitting always reversed packet data, a method for transmitting packet data by a mobile terminal, When the base station detects the occurrence of packet data of the mobile station, variably selecting a signaling system for processing the reverse data in consideration of the available processing capacity; And establishing a call for the enhanced reverse packet data according to the selected reverse data signal system and performing communication with the mobile terminal. The method of claim 1, And the base station transmits an always reversed packet data establishment response message including an identifier indicating the selected signaling scheme to a base station controller. The method of claim 2, And the base station controller further comprises transmitting to the mobile station an always reversed packet data setting message including an identifier indicating the signaling scheme. The method of claim 1, The base station selects a signaling system for mapping one enhanced reverse packet data size identifier (E-TFCI) and a plurality of reverse packet data size information (E-TFC) when the available processing capacity is sufficient. The method. The method of claim 1, The base station selects a signaling system for mapping one enhanced reverse packet data size identifier (E-TFCI) and one reverse packet data size information (E-TFC) when the available processing capacity is insufficient. Way. The method of claim 1, If the available processing capacity is insufficient, the base station selects a signal system for mapping the reverse packet data size identifier (E-TFCI) and the reverse packet data size information (E-TFC) determined at the time of call setup by the base station controller. Characterized in that the method. In the mobile communication system for transmitting always reversed packet data, a method for transmitting packet data by a mobile terminal, When the base station controller detects generation of packet data of the mobile station, variably selecting a signal system for processing the enhanced reverse data in consideration of the available processing capacity of the base station; Transmitting a constant reverse packet data setting message including an identifier indicating the selected reverse data signal system to a base station and a mobile station; And the base station and the mobile station establish a call according to the message to perform always reverse packet data communication. The method of claim 7, wherein And the base station controller variably selecting a signal system for processing the enhanced reverse data in consideration of the amount of enhanced reverse data of the mobile station. The method of claim 7, wherein And the base station controller further comprises transmitting a call setup message to the base station, the call setup message including call setup information for always reversed packet data and an identifier indicating the selected signaling scheme. The method of claim 8, And when the base station controller receives a response message corresponding to the call setup message from the base station, transmitting the call setup message including the identifier indicating the selected signaling scheme to the mobile terminal. Way. The method of claim 7, wherein The base station controller selects a signaling scheme that maps one enhanced reverse packet data size identifier (E-TFCI) and a plurality of reverse packet data size information (E-TFC) if the available processing capacity of the base station is sufficient. The method characterized in that. The method of claim 7, wherein The base station controller selects a signaling scheme that maps one enhanced reverse packet data size identifier (E-TFCI) and one reverse packet data size information (E-TFC) if the available processing capacity of the base station is insufficient. Characterized in that the method.

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