Method for transmitting response information in mobile communications system

Method for transmitting response information in mobile communication system

The present invention is directed to a mobile communication system, and particularly to a method for transmitting response information in a mobile communication system.

Figure 1 is a structural diagram illustrating a "Long Term Evolution (LTE)" system belonging to a mobile communication system. The LTE system is an evolved version of the traditional UMTS system and has been standardized by the 3GPP (3rd Generation Partnership Project).

The LTE can be roughly classified into an "Evolved UMTS Terrestrial Radio Access Network (E-UTRAN)" and a "Core Network (CN)". The E-UTRAN contains at least one eNode-B as a base station, and an "Access Gateway (AG)" connected to an external network at the end of the network.

The AG can be divided into a part dealing with user traffic and a part dealing with control traffic. The AG part for processing user traffic and the AG part for processing control traffic can be connected to each other through a new interface for communication. One or more cells may exist in an eNode-B. These eNode-Bs can be connected by an interface used to transmit user traffic or control traffic.

The CN contains the AG and a node for registering the user of the "User Equipment (UE)". An interface can also be provided in the E-UMTS to classify the E-UTRAN and the CN.

The radio interface protocol layer can be divided into the first layer (L1), the second layer (L2) and the third layer according to the three lower layers of the "Open System Interconnection (OSI)" reference model known in the industry (L3). The physical layer of the first layer (L1) provides information transmission services on a physical channel. A radio resource control (RRC) layer located at the third layer (L3) controls the radio resources between the UE and the network.

The RRC layer can exchange RRC messages between the UE and the network for this project. The RRC layer can be spread to multiple network nodes such as eNode-B and AG, and can also be located at the eNode-B or the AG.

Figure 2 is a conceptual diagram, which illustrates the control aspect of a radio interface protocol structure between the UE and the UTRAN ("UMTS Terrestrial Radio Access Network") based on the 3GPP radio access network standard. The radio interface protocol can be represented by a physical layer, a data layer, and a network layer in the horizontal direction. In the vertical direction, the radio interface protocol can be expressed as a user aspect for transmitting data and a control aspect for transmitting control signals.

The protocol layers in Figure 2 can be classified into a physical layer, a "media access control (MAC)" layer, a "radio link control (RLC)" layer, and a "radio resource control (RRC)" layer.

The physical layer, that is, the first layer, can provide an information transmission service to an upper layer on a physical channel. The physical layer is connected to a "Media Access Control (MAC)" layer located on it through a transmission channel.

The MAC layer communicates with the physical layer through the transmission channel, thereby enabling data transmission between the MAC layer and the physical layer. Data is transferred between multiple different physical layers, such as between a first physical layer on a transmitting side and a second physical layer on a receiving side.

The MAC layer of the second layer (L2) can transmit various services to the RLC ("Radio Service Control") layer through a logical channel, and it is the upper layer. The RLC layer of the second layer (L2) supports reliable data transmission operations.

It should be noted that the RLC layer is depicted by a dashed line, because if the RLC functions are implemented and executed by the MAC layer, the RLC layer itself does not need to exist.

The RRC ("Radio Resource Control") layer located at the lowest part of the third layer (L3) is only defined by the control aspect. The RRC layer controls the logical channels, transmission channels, and physical channels for the configuration, reconfiguration, and release of the "radio bearer (RB)". An RB refers to a service provided by the second layer (L2) for data transmission between the terminal and the E-UTRAN.

Figure 3 is a conceptual diagram, which illustrates a user-oriented structure of the radio interface protocol between the UE and the UTRAN according to the 3GPP radio access network standard. The user of the radio protocol is divided into a physical layer, a MAC layer, an RLC layer, and a "Packet Data Convergence Protocol (PDCP)" layer.

The physical layer of the first layer (L1) and the MAC and RLC layer of the second layer (L2) are used to use an IP packet, such as IPv4 or IPv6, on a radio interface with a relatively narrow bandwidth. Send data efficiently. The PDCP layer performs header compression to reduce the size of a very large IP packet header containing unnecessary control information.

The following text will describe in detail the uplink and downlink for data transmission between the network and the UE. The downlink channel is to send data from the network to the UE. The on-chain channel transmits data from the UE to the network.

Examples of downlink channels are "Broadcast Channel (BCH)" used to transmit system information, and "Shared Channel (SCH)" and "Shared Control Channel (SCCH)" used to transmit user traffic or control traffic. ". The downlink shared channel (SCH) can be used to transmit user traffic or control messages of the downlink multicast service or broadcast service, or it can be transmitted via an additional multicast channel (MCH).

The example of the uplink channel is the "Random Access Channel (RACH)", and the uplink shared channel (SCH) and shared control channel (SCCH) used to transmit user traffic or control messages.

Figure 4 is a conceptual diagram illustrating a hybrid automatic repeat and request (HARQ) rule. Now, referring to Fig. 4, a method for implementing HARQ in the physical layer of the lower link of a radio packet communication system will be described.

Referring now to Figure 4, the eNode-B determines a UE to receive a packet, and packet type information to be transmitted to the UE, such as coding rate, modulation rule, and data volume. The eNode-B informs the UE through a "High Speed Downlink Shared Control Channel (HS-SCCH)" to explain the determined information, and through the "High Speed Downlink Shared Channel (HS-DSCH)," At the time when information is transmitted on the HS-SCCH, a corresponding data packet is transmitted.

The UE receives the downlink control channel, identifies the type and transmission time point of a packet to be transmitted, and receives the corresponding packet. Then the UE attempts to decode the received packet data.

If the UE cannot decode a specific packet, such as data1, the UE transmits a negative acknowledgement (NACK) signal to the eNode-B. The eNode-B recognizes that the packet transmission operation failed, and uses the same packet format or a new packet format to retransmit the same data like data1 at an appropriate point in time. The UE merges the retransmitted packet like the data1 with a previously received packet that failed to decode the packet, and re-attempts to decode the packet.

If the packet is received and successfully decoded, the UE sends an acknowledgment (ACK) signal to the eNode-B. The eNode-B recognizes the successful packet transmission operation, and executes the next packet transmission operation like data2.

The random access channel (RACH) represents a channel used to transmit an initial control message from the UE to the network. The RACH is adapted to implement synchronization between the UE and the network. In addition, if there is no further data for transmission in a UE that intends to transmit data in an uplink direction, the UE can obtain necessary radio resources on the RACH.

For example, when the UE starts up, it tries to access a new cell. The UE performs a downlink synchronization operation and receives system information from a target cell intended by the UE.

When receiving system information, the UE must send an access request message to access the RRC layer. However, the UE is not synchronized to a current network, and the uplink radio resources cannot be guaranteed. This is because the UE uses RACH.

In other words, the UE requests radio resources that can transmit the access request message to the network. If the eNode-B receives the radio resource request signal from the UE, it allocates appropriate radio resources to the UE, thereby sending an RRC connection request message. Then the UE uses the configured radio resources to send the RRC connection request message to the network.

In another example, assume that an RRC connection has been established between the UE and the network. The UE receives radio resources from the network according to the radio resource scheduling process of the network, so that the radio resources can be used to transmit data from the UE to the network.

However, if further data is left in the buffer of the UE for transmission, the network no longer allocates uplink radio resources to the UE. If the network allocates uplink radio resources to the UE, this configuration is considered invalid. The buffer status of the UE is reported to the network periodically or non-periodically.

Therefore, if new data is stored in the buffer of a UE that does not have radio resources, the UE uses RACH because the UE is not configured with uplink radio resources. In other words, the UE requests the necessary radio resources to transmit data to the network.

The following will explain in detail how it is applied to RACH in a "Wide Frequency Code Multiple Access (WCDMA)" system. The RACH is used to transmit data with a short length. Some RRC messages, such as an RRC connection request message, a cell update message, and a URA update message, are sent on the RACH.

Multiple logical channels can be mapped to the RACH. For example, a shared control channel (CCCH), a dedicated control channel (DCCH), and a dedicated traffic channel (DTCH) can be mapped to the RACH. The RACH is mapped to a physical random access channel (PRACH).

Figure 5 is a conceptual diagram illustrating an example of a PRACH ("Physical Random Access Channel") transmission method. That is, as shown in Figure 5, the PRACH is an uplink physical channel and is divided into a preamble part and a message part.

The preceding part performs a power ramp function to adjust the power required to transmit a message, and an anti-collision function to prevent transmissions from multiple UEs from colliding with each other. The message part performs a "MAC protocol data unit (MAC PDU)" transmission operation from the MAC layer to the physical channel.

If the MAC layer of the UE indicates that the physical layer of the UE needs to transmit the PRACH transmission operation, the physical layer of the UE selects a single access slot and a single signature, and transmits the PRACH preamble in the uplink. The preamble can be transmitted during an access slot period of 1.33 ms, and a single signature can be selected from 16 signatures during the initial preset period of the access slot, so that the person can transmit the selected signature.

When the UE transmits the preamble, the eNode-B can transmit a response signal on an acquisition indicator channel (AICH), and this channel is the physical channel of the link. The eNode-B can use a response signal transmitted on the AICH to send a positive response (ACK) or a negative response (NACK) to the UE.

If the UE receives an ACH response signal, the person transmits the message part. If the UE receives a NACK response signal, the MAC layer of the UE instructs the physical layer of the UE to perform PRACH transmission after a preset time. If the UE does not receive a response signal corresponding to the transmitted preamble, after a designated access slot, the UE transmits a new one at a power level higher than a previous preamble. The preceding text.

Although the foregoing description has already disclosed a response signal to the preamble of the RACH, it should be noted that the eNode-B can transmit data or control signals to the UE. Various control signals can be sent from the eNode-B to the UE, such as downlink scheduling information, uplink scheduling permission information, and response information related to the UE's RACH preamble transmission operation.

According to traditional techniques, when the UE transmits data on the RACH, the person transmits the RACH preamble to the eNode-B, and the eNode-B transmits response information related to the RACH preamble to the UE. However, if at least two UEs transmit their RACH preamble at the same or similar time in order to use the RACH, the eNode-B must be aware of the response information related to the individual preamble to each of the two UEs, so it needs to be configured Radio resources are used to transmit response information to each UE, thereby wasting radio resources.

Assuming that the UE uses the HARQ rule when using the radio resources configured on the RACH to transmit data to the eNode-B, the eNode-B not only pre-configures the first radio resource related to the initial transmission data, but also Then, the second radio resource related to data retransmission is configured. Therefore, if the UE successfully transmits data at the first transmission time, the second radio resource for data retransmission is unnecessarily wasted.

An object of the present invention is to provide a method for transmitting response information in a mobile communication system, which can reduce the amount of wasted radio resources and efficiently use radio resources. Another object of the present invention is to provide a mobile communication system, which when two or more UEs have already transmitted the RACH preamble at the same or similar time, the UE-related response information is not transmitted individually, but the RACH The foregoing response information is sent to a specific UE, the related response information is configured in the form of a single data unit on a shared channel, and the configured data unit is sent to the specific UE.

In one feature of the present invention, a method for transmitting a specific preamble and responding to the specific preamble to receive information in a mobile communication system is provided. The method includes transmitting the specific preamble on a random access channel (RACH); receiving response information on a shared channel, the response information including at least one response and identification information corresponding to the at least one response, and the at least one response corresponds to At least one preamble transmitted in a specific time interval; and if the identification information indicates that the at least one response corresponds to the specific preamble, the at least one response is processed.

Considering that the method further includes, if the identification information indicates that the at least one response corresponds to the specific preamble, using the radio resource configured in the at least one response to transmit data. It is further considered that the method further includes receiving a first message containing an indication that the transmitted data was not properly received, and using newly configured radio resources to retransmit the data.

It is considered that the first message contains the newly configured radio resource. It is further considered that the method further includes receiving a second message containing the newly configured radio resource. Preferably, the shared channel is a downlink shared channel (DL-SCH).

In another feature of the present invention, a method for transmitting a preamble and responding to the preamble to receive information in a mobile communication system is provided. The method includes receiving at least one preamble on a random access channel (RACH) during a specific time interval, and transmitting response information on a shared channel, wherein the response information contains a response corresponding to the process during the specific time interval At least one response of the preceding paragraph is received, and identification information for identifying a mobile communication terminal from which the at least one preceding paragraph is received.

Considering that the method further includes configuring radio resources in the response, the radio resources are associated with the data transmission of the mobile communication terminal from which the at least one preceding paragraph is received. It is further considered that the method further includes receiving data from the mobile communication terminal where the at least one preceding paragraph is received, the data being transmitted using the configured radio resources; determining that the data is not properly received; transmitting a data containing and The data retransmits the first message associated with the additional allocated radio resources, and receives the data retransmitted using the radio resources allocated in the message.

It is considered that the method further includes including an indication that the data was not properly received in the first message. It is further considered that the method further includes sending a second message that contains an indication that the data was not received properly. Preferably, the shared channel is a link shared channel (DL-SCH).

In another feature of the present invention, a method for transmitting a specific preamble and responding to the specific preamble to receive information in a mobile communication system is provided. The method includes a specific mobile communication terminal transmitting the specific preamble on a random access channel (RACH); a network transmitting response information on a shared channel, the response information containing a response information corresponding to the process of a specific time interval Received at least one response of the preceding paragraph, and identifying the identification information of a mobile communication terminal from which the at least one preceding paragraph was received; the specific mobile terminal receives the response information; and if the identification information indicates that the at least one response corresponds to the If the preceding text is specific, the specific mobile communication terminal processes the at least one response.

It is considered that the method further includes configuring radio resources in the response in the network, and the radio resources are associated with the data transmission of the mobile communication terminal from which the at least one preceding paragraph is received. It is further considered that the method further includes, if the identification information indicates that the at least one response corresponds to the specific preamble, the specific mobile communication terminal transmits data using the radio resource configured in the at least one response.

Considering that the method further includes receiving data from the mobile communication terminal from which the network receives the at least one preceding paragraph, the data is transmitted using the configured radio resources; the network determines that the data is not properly received ; The network transmits a first message containing additional allocated radio resources associated with data retransmission; and the network receives the data retransmitted using the radio resources allocated in the message. It is further considered that the method further includes the network including an indication that the data was not properly received in the first message.

It is considered that the method further includes the network sending a second message containing an indication that the data has not been received properly. Further consider that the shared channel is the next-chain shared channel (DL-SCH).

Other characteristics and advantages of the present invention will be partly in the following description and partly obvious from the description, or can be stated in a manner known to implement the present invention. It should be understood that the general description of the previous disclosure and the detailed description of the latter are only exemplary and explanatory, and are used to provide further explanation of the present invention.

For those who are familiar with this art, the specific embodiments will be described in detail and refer to the accompanying drawings. These and other specific embodiments will also be obvious, but the present invention is not limited to any disclosed Specific embodiments.

Pursuant to 35 USC § 120, this application claims the rights of U.S. Provisional Application No. 60/771,305 filed on February 7, 2006, and Case No. 60/815,722 filed on June 21, 2006, hereby Incorporate these contents into this case as a whole. Pursuant to 35 USC§ 119(a), this application claims the right and priority of the earlier filing date of Korean Patent Application No. P2006-0107105 filed on November 1, 2006. The content of this case is hereby It is incorporated into this case as a whole.

Now, reference will be made in detail to various preferred embodiments of the present invention, and these examples are described in the accompanying drawings. The same reference numbers will be used as much as possible in the drawings throughout the text to refer to the same or similar parts.

Hereinafter, referring to the accompanying drawings, a method for transmitting response information in a mobile communication system according to the present invention will be described. For ease of description and a better understanding of the present invention, the term "UE" will be used to refer to a transmission entity of an uplink signal, and the term "eNode-B" will be used to refer to a receiving entity of the uplink signal. However, it should be noted that the scope of the terminal and the base station is not limited to the above vocabulary, and the vocabulary "UE" and the vocabulary "eNode-B" can also be used to refer to a terminal and a base station respectively.

FIG. 6 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to an embodiment of the present invention. The following will describe a method for transmitting response information associated with at least one UE previous transmission operation at a time.

The UE uses the RACH to perform RRC connection requests, cell updates, handover operations, uplink radio resource requests, and synchronization maintenance operations related to the eNode-B. The UE will send a preamble before sending data. The foregoing is used to adjust the transmission power necessary for data transmission and to prevent multiple UEs from colliding with each other.

When using RACH, the UE transmits the RACH preamble to the eNode-B, and the eNode-B transmits the RACH preamble response information to the UE. The eNode-B does not independently transmit response information related to other UEs. Each of these transmits the RACH preamble at the same or similar time, but transmits information related to other UEs on a shared channel at the same time. 'S response information.

For example, if a first UE, a second UE, and a third UE transmit their RACH preambles to the eNode-B within a predetermined period of time, the eNode-B will be configured in the form of a single data unit The response information related to the first to third UEs, and the single data unit is transmitted to the first to third UEs on a shared channel, thereby responding to the RACH of the first to third UEs Preamble.

That is, as shown in Figure 6, at step S60, the first UE (UE1) transmits its RACH preamble to the eNode-B, and the second UE (UE2) is the same as the RACH preamble for transmitting the first UE or Transmit its RACH preamble to the eNode-B at a similar time. In other words, the first UE (UE1) and the second UE (UE2) transmit their RACH preamble to the eNode-B at the same or similar time.

Therefore, the eNode-B will have a preset time (<i>t</i>In the process of ), at least one RACH preamble is received from at least two UEs. Although Figure 6 only illustrates the first (UE1) and the second (UE2) UE, those who are familiar with this technique can definitely know that the number of UEs can be "N", and the present invention can also be applied to N UE.

The eNode-B receives the RACH preamble of the first (UE1) and the second (UE2) UE, and transmits the received RACH response information at step S62. The eNode-B transmits the response information on a shared channel, and there is no need to allocate a unique radio resource RF channel to the first (UE1) and the second (UE2) UE to reply to the RACH preambles. The shared channel allows all UEs in a cell to receive or read data from the eNode-B.

FIG. 7 is a conceptual diagram, which illustrates a method for transmitting response information to a UE on a link shared channel (DL-SCH) belonging to a shared channel according to a specific embodiment of the present invention. Generally speaking, the DL-SCH is used to transmit data from the eNode-B to the default UE, or to transmit data to all UEs in a cell. Therefore, different UEs can receive data on the DL-SCH.

Although the Node-B simultaneously transmits response information related to multiple UEs on the DL-SCH, each UE can receive its response information from the Node-B. The eNode-B transmits response information related to the RACH preambles to the UEs on the DL-SCH. The single data unit of the response information contains a plurality of response information related to a plurality of UEs.

That is, as shown in Figure 7, the UE must first read the downlink shared control channel (DL-SCCH) to read the data of the DC-SCH. The location information of the DL-SCH is transmitted on the DL-SCCH.

In other words, after transmitting the RACH preamble, the UE reads the DL-SCCH, thereby receiving response information from the eNode-B, and then identifies the location information of the DL-SCH related to the DL-SCCH. The control signal related to the physical layer and/or the second layer is transmitted from the eNode-B to the UE on the DL-SCCH.

The DL-SCCH payload has various types of information, such as a UEID (identification code) used to indicate which UE will receive the data; location information related to frequency or time, which indicates which DL-SCH data will be read by the UE Obtain; the specific information needed by the UE that intends to read the DL-SCH data; and the decoding information. In this way, the UEID included in the DL-SCCH can be used to identify which UE will receive specific DL-SCH data.

That is, as shown in Figure 6, the DL-SCH payload has first response information for the first UE (UE1) and second response information for the second UE (UE2). In other words, the first UE (UE1) and the second UE (UE2) read the same DL-SCCH and determine the same DL-SCH position.

The first UE (UE1) and the second UE (UE2) read their unique response information on the same DL-SCH. At the second layer of the eNode-B, by multiplexing the response information of each UE, the response information of the RACH preamble from multiple UEs at the same or similar time can be sent to the Wait for the UE.

The eNode-B can configure and set the RACH preamble response information sent by multiple UEs at the same or similar time. The response information is configured in the form of a single MAC "Protocol Data Unit (PDU)".

The following will refer to Tables 1 and 2 to describe a method for multiplexing the response information of the UEs to configure and configure a single MAC PDU and transmit the single MAC PDU.

A representative example of the PDU configured by multiplexing the response information can be shown in Table 1:<tables><img file="TW200746674A_D0001.tif" /></tables>

That is, as shown in Table 1, the eNode-B will configure and set the header of a first UE before the response information of the first UE. The header contains a UE ID indicating which UE read the response information, and also contains specific information indicating the length of the response information.

The eNode-B configures and sets the response information of the first UE after the first UE header. The response information of the first UE includes the uplink radio resource allocated to the first UE, an identification code in a cell, a temporary identification code of the first UE, and a synchronization operation with the eNode-B The relevant compensation value.

After the first UE header and the response information of the first UE are configured, the eNode-B configuration sets the header of the second UE and the response information of the second UE. In this way, the PDU generated by incorporating the response information of multiple UEs into a single response information can be configured.

Another representative example of a single PDU configured by multiplexing the response information can be shown in Table 2.

That is, as shown in Table 2, a header containing the identification code of the first UE and the length of the response information is attached to the MAC PDU. This header provides the same functions as the header described in Table 1.

<tables><img file="TW200746674A_D0002.tif" /></tables>

The header of the second UE is attached to the PDU after the header of the first UE. In this way, the PDU contains the same header as the number (N) of UEs for which the response information should be included in the single response information.

An indication indicating the end of the header is attached to the end of the header. The eNode-B can use this header to identify the beginning of the response information. After that, the MAC PDU is constructed by sequentially attaching the response information of individual UEs.

The response information of each UE includes the information of the uplink radio resources allocated to each UE, an identification code in the cell, a temporary identification code of the UE, and a compensation value related to the synchronization operation of the eNode-B. Each UE recognizes its own response information among multiple response information that has been multiplexed into a single response information and transmitted on the shared channel. Each UE uses the response information related to its RACH channel, which is allocated to each UE's uplink radio resources to transmit data to the eNode-B.

FIG. 8 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to another embodiment of the present invention. In detail, Figure 8 illustrates a scheduling method for a specific situation, in which a HARQ (Hybrid ARQ) rule is used when transmitting data to the eNode-B.

That is, as shown in Figure 8, at step S70, the first UE (UE1) transmits its RACH preamble to the eNode-B, and the second UE (UE2) is similar to that shown in Figure 6, At step S71, the RACH preamble is transmitted to the eNode-B. The first UE (UE1) and the second UE (UE2) receive response information configured in the form of a single data unit on a shared channel like DL-SCH at step S72.

Then, each UE uses the uplink radio resources allocated to each UE in the response information related to each RACH preamble to transmit the data to the eNode-B. It should be noted that Figure 8 only illustrates a data transmission/reception processing procedure between the second UE (UE2) and the eNode-B after receiving the response information. Those who are familiar with this art will know that the above processing procedure can also be applied to the first UE (UE1) in the same way as for the second UE (UE2).

Assuming that the HARQ rule is used when each UE uses the uplink radio resources configured on the RACH to transmit data to the eNode-B, the uplink radio resources for data retransmission will not be pre-configured, and When data needs to be retransmitted due to the eNode-B decoding failure, it is configured by a NACK signal and transmitted to each UE. The uplink radio resources used for data retransmission can be included in the NACK signal. A specific control signal can be used to allocate the uplink radio resources for data retransmission to the UE.

That is, as shown in Figure 8, after receiving the response information from the eNode-B, the second UE (UE2) transmits the data to the eNode-B in step S73. The second UE (UE2) applies a HARQ rule when transmitting the above-mentioned data to the eNode-B. The eNode-B notifies the UEs of the HARQ rule setting operation through system information.

The eNode-B receives data from the second UE (UE2) and decodes the received data. If the eNode-B does not decode the data correctly, the person sends a NACK signal to the second UE (UE2) at step S74, thereby indicating a decoding error.

The eNode-B allocates radio resources necessary for data retransmission to the second UE (UE2), and simultaneously transmits information related to the allocated radio resources together with the NACK signal. In other words, when the eNode-B transmits the response information of the preamble of the RACH to the UE, the uplink radio resource configuration information in the response information is only related to the first transmission of the HARQ.

For example, if the radio resources necessary for data transmission after the RACH preamble have a specific value of 100, and the data needs to be retransmitted due to the HARQ operation, the UE requests 100 radio resources again. If the data is retransmitted and applied to the RACH preamble where the eNode-B allocates uplink radio resources to the UE, the 200 radio resources will be allocated to the UE.

However, when the radio resources are allocated according to the response information such as the RACH preamble of the UE, the eNode-B only allocates 100 radio resources related to the first transmission to the UE according to the present invention. Afterwards, if a UE's data transmission operation fails and data needs to be retransmitted, the eNode-B not only additionally configures the NACK signal, but also allocates 100 additional radio resources to the UE.

The specific control signal containing the radio resource allocation information necessary for data retransmission can be transmitted according to the same format as the response information for the preamble of the RACH. At the same time, a frequency channel used when the eNode-B allocates radio resources to the UE can also be used as an example of the present invention.

At step S75, the second UE (UE2) retransmits the data according to the uplink radio resource configuration information previously transmitted by the NACK signal.

FIG. 9 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to another embodiment of the present invention. In detail, Figure 9 illustrates a scheduling method for a specific situation, in which a HARQ (Hybrid ARQ) rule is used when transmitting data to the eNode-B. One difference from the situation in Fig. 8 is that it is not necessary to include the uplink radio resources used for data retransmission in the NACK signal, but are transmitted separately by the NACK signal at the same or another time.

That is, as shown in Figure 9, at step S80, the first UE (UE1) transmits its RACH preamble to the eNode-B, and the second UE (UE2) is similar to that shown in Figures 6 and 8. In the manner shown, the RACH preamble is sent to the eNode-B at step S81. The first UE (UE1) and the second UE (UE2) receive response information configured in the form of a single data unit on a shared channel like DL-SCH at step S82.

Then, in step S83, each UE uses the uplink radio resources allocated to each UE in the response information related to each RACH preamble to transmit the data to the Node-B. It should also be noted that Figure 9 only illustrates a data transmission/reception processing procedure between the second UE (UE2) and the eNode-B after receiving the response information. Those who are familiar with this art will know that the above processing procedure can also be applied to the first UE (UE1) in the same way as for the second UE (UE2).

The second UE (UE2) applies a HARQ rule when transmitting the above-mentioned data to the eNode-B. The eNode-B preferably informs the UE of the HARQ rule setting operation through system information.

Assuming that the HARQ rule is used when each UE uses the uplink radio resources configured on the RACH to transmit data to the eNode-B, the uplink radio resources for data retransmission will not be pre-configured, and When the eNode-B fails to decode and needs to retransmit data, it is configured by a NACK signal and transmitted to each UE. The uplink radio resources used for data retransmission can be included in the NACK signal. At step S84, when data needs to be retransmitted due to the eNode-B decoding failure, the NACK signal is transmitted. And configure radio resources for data retransmission on the chain. That is, the uplink radio resources for data retransmission will not be pre-configured, but will be configured and transmitted to each UE when retransmission is necessary. A specific control signal can be used to allocate the uplink radio resources for data retransmission to the UE. The specific control signal may be a signal used by the eNode-B for SR ("scheduled resource") at step S85. The specific control signal can also be a signal for scheduling information or any other signal.

The specific control signal containing the radio resource allocation information necessary for data retransmission can be transmitted according to the same format as the response information for the preamble of the RACH. At the same time, a frequency channel used when the eNode-B allocates radio resources to the UE can also be used as an example of the present invention.

At step S86, the second UE (UE2) retransmits the data according to the uplink radio resource configuration information previously transmitted through the specific control signal, such as SR.

That is, as described herein, a method for transmitting response information in a mobile communication system according to the present invention can effectively utilize radio resources, thereby reducing the amount of wasted radio resources.

Those who are familiar with this technique will understand that various modifications and changes can be made in the present invention without departing from the spirit or scope of the present invention. Therefore, what is desired is that the present invention covers various modifications and changes of the present invention, if the attribution is within the scope of the patent application set out later and its equivalent items.

Since the present invention can be implemented in various forms without departing from its spirit or basic characteristics, it should also be understood that the above-mentioned specific embodiments are not limited to any details described in the preceding disclosure, unless otherwise specified. It should be interpreted broadly within the spirit and scope defined in the scope of the patent application set out below. Therefore, all changes and modifications within the domains and limits that belong to the scope of the patent application, or equivalent items of these domains and limits, shall be covered by the scope of the subsequent patent application.

The specific embodiments and advantages disclosed above are only exemplary, and should not be construed as limiting the present invention. This teaching can then be applied to other types of equipment.

The description of the present invention is of an explanatory nature, and is not intended to limit the scope of the patent application. For those who are familiar with this art, numerous alternatives, modifications and changes are indeed obvious. In the scope of the patent application, the device + function statement is used to cover the structure quoted here to perform the function, and at the same time not only each structural equivalent item, but also each equivalent structure.

The accompanying drawings are incorporated for further understanding of the present invention, and are incorporated to form a part of this application. These drawings illustrate the specific embodiment(s) of the present invention and are explained in conjunction with the detailed description. Principles of the invention. In different drawings, the properties, elements, and features of the present invention referenced by the same number represent the same, equivalent or similar properties, elements, and features according to one or more specific embodiments.

Figure 1 is a structural diagram illustrating a "Long Term Evolution (LTE)" system belonging to a mobile communication system.

Figure 2 is a conceptual diagram illustrating the control layers of one of multiple radio interface protocols.

Figure 3 is a conceptual diagram illustrating the user-oriented layers of one of multiple radio interface protocols.

Figure 4 is a conceptual diagram illustrating a hybrid ARQ (HARQ) rule.

Figure 5 is a conceptual diagram illustrating an example of a PRACH ("Physical Random Access Channel") transmission method.

FIG. 6 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to an embodiment of the present invention.

FIG. 7 is a conceptual diagram, which illustrates a method for transmitting response information to a UE on a shared channel according to a specific embodiment of the present invention.

FIG. 8 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to another embodiment of the present invention.

FIG. 9 is a flowchart illustrating a method for transmitting response information in a mobile communication system according to another embodiment of the present invention.