KR100912710B1 - Mobile communication system and radio resource control setup method thereof - Google Patents

Abstract

The present invention relates to a mobile communication system and a method for establishing a radio resource control (RRC) connection thereof, the method comprising: receiving an RRC connection request message from a terminal; And transmitting an RRC connection establishment message to the terminal, and if the RRC establishment complete message is not received until a predetermined time elapses, increasing the transmission power level to retransmit the RRC connection establishment message. Regardless of the changes in the wireless environment, the RRC connection establishment process can be performed stably, and since the RRC connection establishment message is retransmitted at a power level increased from the previous transmission power level, the reception success rate of the RRC connection establishment message at the terminal can be greatly improved. It has an effect.

In addition, before the RRC connection establishment message is transmitted by increasing the transmission power level, the RRC connection establishment message may be repeatedly transmitted to the UE faster by transmitting the RRC connection establishment message in a shorter period. Accordingly, the RRC connection establishment is completed. By receiving messages faster, you can avoid unnecessary consumption of transmit power and have the advantage of completing the RRC connection process quickly.

Terminal, UTRAN, RNC, RRC, connection, configuration, power

Description

Mobile communication system and radio resource control setup method

1 is a simplified diagram showing the configuration of a mobile communication system according to an embodiment of the present invention;

2 is a flowchart illustrating a method of establishing an RRC connection according to an embodiment of the present invention;

3 is a diagram illustrating a data flow in an RRC connection establishment method according to an embodiment of the present invention;

4 is a graph illustrating a transmission power level according to RRC connection establishment message retransmission in the RRC connection establishment method according to an embodiment of the present invention;

5 is a flowchart illustrating a method of establishing an RRC connection according to another embodiment of the present invention;

6 is a diagram illustrating a data flow in an RRC connection establishment method according to another embodiment of the present invention; and

7 is a graph illustrating a transmission power level according to RRC connection establishment message retransmission in the RRC connection establishment method according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

UE: mobile communication terminal RNC: wireless network controller

M1 to M3: RRC connection establishment message

The present invention relates to a mobile communication system and a method for establishing a radio resource control connection thereof, and in particular, when the system performs an RRC connection establishment process with a terminal, an RRC connection establishment message is repeatedly transmitted to the terminal over and over again, thereby stably RRC. The present invention relates to a mobile communication system capable of performing a connection process and a method for establishing a radio resource control connection thereof.

Based on the 3GPP radio access network standard, a radio interface protocol between a terminal and a UTRAN (UMTS Terrestrial Radio Access Network) is composed of a physical layer, a data link layer, and a network layer horizontally and vertically for data information transmission. It is divided into a user plane and a control plane for transmitting control signals. In addition, such protocol layers may be divided into first, second, and third layers based on the lower three layers of the OSI seven layers.

The radio resource control (RRC) layer located at the bottom of the third layer is defined only in the control plane and controls the control of transport channels and physical channels in connection with setting, resetting, and releasing radio bearers (RBs). In charge. In this case, the RB refers to a service provided by the second layer for data transmission between the UE and the UTRAN. In general, the RB is configured to define characteristics of a protocol layer and a channel necessary to provide a specific service. The process of setting specific parameters and operation methods.

The RRC state indicates whether or not the RRC of the UE is connected to the RRC of the UTRAN. If the RRC state is connected, the RRC connection state is called. When the user first turns on the terminal, the terminal first searches for a suitable cell to which it can connect, and then stays idle in the cell. When it is necessary to establish an RRC connection, the terminal staying in the dormant state is connected to the RRC of the UTRAN through the RRC connection process and then transitions to the RRC connected state.

In this RRC connection process, the UE transmits an RRC connection request message to the UTRAN, and in response, the UTRAN transmits an RRC connection setup message to the UE, and the UE again transmits an RRC connection to the UTRAN. There are three steps to sending a RRC connection setup complete message.

However, in the general RRC connection process as described above, since the RRC connection configuration message transmitted from the UTRAN to the terminal is transmitted only once, the RRC connection configuration fails if the terminal does not successfully receive the RRC connection configuration message. The user cannot use the desired mobile communication service.

In particular, since a message is transmitted and received between the terminal and the UTRAN in a wireless environment, and the wireless environment changes from time to time, if the wireless environment temporarily worsens when the RUT connection setting message is transmitted from the UTRAN to the terminal, the RRC connection setting message is not normally transmitted to the terminal. Since the wireless environment improves again, there is a problem in that the mobile communication service cannot be used unless the RRC connection process is newly performed.

The present invention is to solve the above-mentioned problems, an object of the present invention in the RRC connection process, the mobile communication system and the RRC connection setup process can be made more stable since the RRC connection setup message is repeatedly transmitted to the terminal To provide an RRC connection method.

Another object of the present invention is an RRC connection establishment message in a terminal by transmitting an RRC connection establishment message at a power level increased from a previous transmit power level when the RRC connection establishment message is repeatedly retransmitted in the RRC connection process. The present invention provides a mobile communication system and a method for establishing an RRC connection thereof that can further increase the reception success rate of the RRC.

In addition, another object of the present invention, in the RRC connection process, by repeatedly transmitting the RRC connection establishment message in a shorter period, before transmitting the RRC connection establishment message by increasing the transmission power level, the RRC connection establishment message of the terminal The present invention provides a mobile communication system and a method for establishing an RRC connection thereof that can not only increase a reception success rate but also complete an RRC connection process more quickly.

RRC connection setting method of a mobile communication system according to a first aspect of the present invention for achieving the above object of the present invention comprises the steps of: receiving an RRC connection request message from the terminal; And transmitting an RRC connection establishment message to the terminal, and if the RRC establishment complete message is not received until a predetermined time elapses, increasing the transmission power level to retransmit the RRC connection establishment message.

In addition, RRC connection setting method of a mobile communication system according to a second aspect of the present invention for achieving the above object comprises the steps of: receiving an RRC connection request message from the terminal; Transmitting an RRC connection establishment message to the terminal and repeatedly transmitting the RRC connection establishment message at a first set time interval; And retransmitting the RRC connection establishment message by increasing the transmission power level if the RRC establishment completion message is not received until the second establishment time elapses.

In addition, in a mobile communication system including a mobile communication terminal according to a third aspect of the present invention for achieving the above object, and an RNC for transmitting and receiving data with the terminal, the RNC is to establish an RRC connection to the terminal A first timer for checking a time interval for resending the RRC connection establishment message after transmitting the message; And an RRC connection controller for increasing the level of transmission power and retransmitting the RRC connection configuration message to the terminal when the RRC configuration completion message is not received until the time according to the first timer elapses.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a simplified diagram showing the configuration of a mobile communication system according to an embodiment of the present invention, a diagram illustrating a network structure of a UMTS applied to a WCDMA system.

Referring to FIG. 1, a universal mobile telecommunication system (UMTS) according to a preferred embodiment of the present invention is composed of a user equipment (UE), a UTRAN, and a core network (CN). The UTRAN consists of one or more Radio Network Sub-systems (RNS), each RNS controlling a radio resource in the RNS and delivering a data transmitted through the UTRAN to an appropriate node (RNC; Radio Network Controller) and one or more node-Bs managed by the RNC and responsible for data transmission and reception through a radio interface (Uu) between the UE and the UTRAN. In addition, one or more cells exist in one node-B.

Core Network (CN) is a network that handles subscriber's call processing, mobility control, and switches within the network. Networks such as Mobile Switching Center (MSC), GPRS Gateway Support Node (GGSN), and Home Location Register (HLR) It contains management nodes and the interface between the core network and UTRAN is called Iu.

The air interface protocol between the UE and the UTRAN includes a Radio Resource Control (RRC) layer that transfers and controls all parameters necessary for using radio resources between the UE and the UTRAN. The RRC layer is responsible for setting up and releasing a radio bearer (RB) between the terminal and the UTRAN, and defines various RRC procedures for exchanging configuration information necessary for radio resource management, thereby exchanging control information between the terminal and the UTRAN. To do this, an RRC connection must be established at the beginning of the connection.

RRC connection may be made by transmitting and receiving data to and from the terminal in the RNC managing radio resources, in particular the RNC according to a preferred embodiment of the present invention RRC connection control unit for repeating or retransmitting the RRC connection configuration message at a predetermined time interval, and At least one timer may be included to check this time interval. Accordingly, the RNC increases a transmission power to determine a first time interval for transmitting an RRC connection establishment message, and a second time interval for repeatedly transmitting the RRC connection establishment message regardless of increase or decrease of transmission power. It may include a timer, the second timer may be set to a time shorter than the time set in the first timer.

2 is a flowchart illustrating a method of setting an RRC according to an exemplary embodiment of the present invention.

First, in step S10, the RNC receives the RRC connection request message sent from the terminal to establish the RRC connection. The RRC connection request message may include an initial terminal identifier of the terminal and an RRC connection reason, and the like. The initial terminal identifier refers to a terminal unique identifier capable of identifying the terminal in any region of the world. There may be various reasons for the RRC connection. For example, there may be a response to a call attempt or paging.

In response to the received RRC connection request message, the RNC determines a quality of service (QoS) for a required service in step S20, and then an RRC connection establishment message including basic information, physical channel information, etc. of the terminal according to the expected transmission capacity. Create and send to the terminal. In this case, the RRC connection configuration message may include an initial terminal identifier, a radio network temporary identifier, and radio bearer configuration information. The radio network temporary identifier is a terminal identifier allocated by the UTRAN to identify a connection state terminal and can be used only when an RRC connection exists. Therefore, after the RRC connection is established, the RNC communicates with the terminal using the radio network temporary identifier instead of the initial terminal identifier.

When the terminal successfully receives the RRC connection setup message, after completing the connection setup according to the command included in the received message, generates an RRC connection setup complete message indicating this and transmits to the RNC. In this case, the RRC connection setup complete message may include performance information of the terminal. Therefore, in step S30, it is determined whether the RRC connection establishment complete message has been received from the terminal for a predetermined time, and if it is not received as a result of the determination, in step S40, the transmission power level of data is increased, and in step S50, the RRC connection establishment message Resend

In this case, a predetermined time for determining whether to receive the RRC connection setup complete message may be set in the RNC, which will be described with reference to Table 1 below.

Parameter Range Unit Comment T_RRCRe {100, 150, 200, ,,, 900, 950, 1000} msec When adjusted in 50ms step

Referring to Table 1, a predetermined time for retransmission of the RRC connection setup message can be set at intervals of 50 ms in a range of 100 ms to 1000 ms, and since such time interval is not limited to 50 ms, the RNC is considered in consideration of changes in the wireless environment. Can be adjusted appropriately. In addition, in general, since it takes about 300 ms to 400 ms to receive the RRC connection setup complete message in response to the RRC connection setup message to the terminal can be set in consideration of this. For example, if the T_RRCRe value is set to 100 ms, the RRC connection setup message can be retransmitted about 3 to 4 times. If the T_RRCRe value is set to 120 ms when the 20 ms interval can be set, the RRC connection setup message is weak. You can resend three times.

When the process of steps S30 to S50 is repeatedly performed several times, in step S60, it is determined whether the number of times of execution has reached a preset number of repetitions in the RNC, and if it is retransmitted as many times as the determination result, it is determined that the RRC connection has failed.

In this case, the number of retransmissions of the RRC connection configuration message may be set in the RNC, which will be described with reference to Table 2 below.

Parameter Range Value Comment N_RRCRe 0 to 4 0 Resend RRC Connection Setup Message One Up to one resend of the RRC connection establishment message 2 Up to 2 resends of RRC connection establishment message 3 Up to 3 times of RRC connection establishment message retransmission 4 Up to 4 resend RRC connection establishment messages

As described above, the number of retransmissions of the RRC connection establishment message may be determined with reference to the time taken from when the RRC connection establishment message is transmitted to when the RRC connection establishment completion message is received. As shown in Table 2, The RRC connection establishment message may be retransmitted, and various values may be set within a range that does not exactly match the values in Table 2.

The RRC connection setup message determines whether an RRC connection setup complete message has been received from the UE at a T_RRCRe time interval, and if not received, retransmits the message. For example, if the number of retransmissions is set to two, the RRC connection setup message is RRC twice in a T_RRCRe time interval. If the RRC connection establishment complete message is not received until the T_RRCRe time elapses after retransmitting the connection establishment message and the second retransmission of the message, it is determined that the connection establishment has failed.

In addition, in repeating the process of steps S30 to S50, when the RRC connection setup complete message is received from the terminal, it is determined that the RRC connection setup is successfully performed to provide the mobile communication service requested from the terminal.

3 is a diagram illustrating a data flow in the RRC configuration method according to an embodiment of the present invention.

Referring to FIG. 3, upon receiving an RRC connection request message from a terminal, the RNC transmits an RRC connection establishment message. Next, if the RRC connection setup complete message is not received from the UE within a predetermined time (T_RRCRe), the transmission power level is increased by one step to transmit the RRC connection setup message. In addition, if the RRC connection setup complete message is not received from the UE within a predetermined time (T_RRCRe), the transmission power level is increased by one step again to transmit the RRC connection setup message, and the process is repeated to the number (N_RRCRe) set by the RNC. Resend the RRC connection establishment message.

In addition, if the RRC connection setup completion message is not received from the time of first transmission of the RRC connection setup message by repeating the set number of times until the predetermined time (T_RRCSetupComplete), the RNC determines that the RRC connection setup with the UE has failed and establishes the RRC connection setup. End the process.

Meanwhile, an increased transmission power level in retransmitting the RRC connection establishment message may be set in the RNC, which will be described with reference to Table 3 below.

Parameter Range Unit RRCStepup {0, 1, 2, 3, 4, 5} dB

Referring to Table 3, the transmission power level may be increased step by step according to the value set in the RRCStepup parameter. For example, when the RRC connection setup message is 1dB, the transmit power value is 1dB, and when the value of the RRCStepup parameter is set to 1dB, the RRC connection setup message is 2dB, which is 1dB more than the transmit power value that originally transmitted the RRC connection setup message. And RRC connection setup message again at 3dB.

In this case, dB, which is a unit of the transmission power level, is a relative value, so that it can be transmitted by increasing the transmission power to the set dB compared to the previous transmission power. It may be set. In addition, when the transmission power is increased step by step and reaches the maximum transmit power value that can be transmitted, a subsequent RRC connection establishment message may be continuously transmitted at the maximum transmit power value.

4 is a graph illustrating a transmission power level according to retransmission of an RRC connection configuration message in an RRC configuration method according to an embodiment of the present invention.

In the RRC connection establishment method according to the preferred embodiment of the present invention, when the RRC connection establishment message is retransmitted, the transmission power level is also increased and transmitted. Referring to FIG. 4, the power level when the RRC connection establishment message M1 is transmitted for the first time is P1. When the RRC connection establishment message M2 is transmitted next, the RRCStepup value is larger than P1. Transmit at P2 value which is the increased power level. In addition, when the RRC connection establishment message is to be transmitted after the T_RRCRe time elapses, the RRC connection establishment message M3 is transmitted at a P3 value that is a power level that is increased by an RRCStepup value from the P2 value.

5 is a flowchart illustrating a RRC setting method according to another embodiment of the present invention.

As described above with reference to FIG. 2, in step S100, an RRC connection request message is received.

In step S110, the RNC generates and transmits an RRC connection establishment message corresponding to the received RRC connection request message to the terminal.

In step S120, the RNC determines whether the repetitive transmission function is set in itself, and if the repetitive transmission function is set as a result of determination, in step S130, the RRC connection setting message is repeatedly transmitted several times at a predetermined time interval.

In this case, the time interval may be set by the RNC. If any one of the RRC connection establishment messages repeatedly transmitted after the RRC connection establishment message arrives at the terminal even though the RRC connection establishment message initially transmitted to the terminal does not arrive normally according to a drastic change in the wireless environment. It can be seen that the object is achieved.

At this time, each parameter that can be set in relation to the repetitive transmission function that can be set in the RNC will be described with reference to Table 4 below.

Parameter Value Comment RRC-Setup-Quick-Repetition off In all cases operation off All In all cases operation on Ec / lo based It operates when measured Ec / lo value is below RRCQuickRepet_Ec / lo Threshold value RSCP based It is operated when measured RSCP value is below RRCQuickRepet_RSCP Threshold value.

Referring to Table 4, the RRC connection setup message repetitive transmission function can be selectively operated according to the configuration of the RNC, that is, the system. Can be determined.

In more detail, for example, if the parameter value is set to 'on', the repeated transmission function is executed unconditionally regardless of which wireless environment the terminal is in. In addition, if it is set to 'Ec / lo based', the repeat transmission function may be executed only when the Ec / lo value included and received when the UE transmits the RRC connection request message to the RNC is less than a predetermined range. If a certain range, that is, less than the RRCQuickRepet_Ec / lo_Threshold value, the wireless channel environment is predicted to be bad, and the message may be repeatedly transmitted to increase the reception success rate of the RRC connection establishment message.

In addition, if it is set to 'RSCP based', the received signal code power (RSCP) value measured by measuring the transmission power value of the received message when the message transmitted from the terminal is received is a predetermined range, that is, the RRCQuickRepet_RSCP_Threshold value In the following case, it may be determined that the radio channel environment is deteriorated, and the message may be repeatedly transmitted to increase the reception success rate of the RRC connection establishment message.

The specific range and setting unit for the RRCQuickRepet_Ec / lo_Threshold and RRCQuickRepet_RSCP_Threshold values may be set as shown in Table 5 below, but are not limited thereto.

Parameter Range Unit RRCQuickRept_Ec / lo_Threshold -20 dB to 0 dB 1 dB RRCQuickRept_RSCP_Threshold -120 dBm to -50 dBm 1 dBm

Next, in step S140, it is determined whether the RRC connection setup complete message has been received from the terminal for a predetermined time since the first time the RRC connection setup message is sent, if the RRC connection setup complete message is not received in step S150 Increasing the transmit power level transmits the RRC connection establishment message back to the terminal.

If the process of steps S140 to S150 is repeatedly performed several times, in step S160, it is determined whether the number of times of execution has reached the set number of repetitions set in the RNC. The RRC connection operation is terminated by determining that the RRC connection has failed.

In addition, in repeating the processes of steps S140 to S150, when the RRC connection setup complete message is received from the terminal, it is determined that the RRC connection setup is successfully performed to provide the mobile communication service requested from the terminal.

6 is a diagram illustrating a data flow in an RRC setting method according to another embodiment of the present invention.

Referring to FIG. 6, upon receiving an RRC connection request message from a terminal, the RNC transmits an RRC connection establishment message. Next, the RRC connection establishment message is repeatedly transmitted for a predetermined number N_RRCQuick at a predetermined time interval T_RRCQuick. Next, when the RRC connection setup complete message is not received from the UE within another predetermined time T_RRCRe, the RRC connection setup message is transmitted by raising the transmission power level by one step. In addition, the RRC connection establishment message is repeatedly transmitted by the set number N_RRCQuick at the predetermined time T_RRCQuick interval. In this case, the RRC connection establishment message repeatedly transmitted is transmitted to the UE at a transmission power level that is increased by one step in the previous process.

At this time, the time interval and the set number of times that the RRC connection configuration message is repeatedly transmitted may be set among the values shown in Table 6 below.

Parameter Range Unit Comment T_RRCQuick {10, 30, 50, ,,, 500} msec 20ms step adjustable N_RRCQuick {0, 1, 2, 3, 4, 5} Count

Referring to Table 6, the RNC repeatedly transmits the RRC connection establishment message at the same transmit power level within the T_RRCRe time. The parameter T_RRCQuick, which is a parameter for the time interval for repeatedly transmitting the RRC connection establishment message, is in a 20 ms unit in a range of 10 ms to 500 ms. It can have a value set to. The value of T_RRCQuick is preferably smaller than the value of T_RRCRe. In general, since the time transfer interval (TTI), which is a data transmission / reception period, is 10 ms in the mobile communication system, the T_RRCQuick value may be set to the minimum value.

The number of repetitions transmitted within the T_RRCRe time may be set to any one of values shown in Table 6, and may be determined by the parameter value because data should be transmitted at T_RRCQuick interval within the T_RRCRe time.

In addition, if the RRC connection establishment complete message is not received from the UE within another predetermined time T_RRCRe, the RRC connection establishment message is transmitted by increasing the transmission power level by one step, and the process is repeated to set the number N_RRCRe. Resend the RRC connection establishment message by).

In addition, if the RRC connection setup complete message is not received until the time (T_RRCSetupComplete) of retransmitting the RRC connection setup message for the set number from the time of first sending the RRC connection setup message, the RNC determines that the connection setup with the UE has failed and the RRC connection has failed. Complete the setup process.

7 is a graph illustrating a transmission power level according to RRC connection establishment message retransmission in the RRC connection establishment method according to another embodiment of the present invention.

In the RRC connection establishment method according to an embodiment of the present invention, when the RRC connection establishment message is retransmitted, the transmission power level is also increased and transmitted. However, the RRC connection establishment message repeatedly transmitted to the UE for a time until the transmission power level is increased until retransmission is transmitted without increasing or decreasing the set transmission power level.

In more detail with reference to FIG. 7, after the first RRC connection establishment message is sent at the P1 power level, when a predetermined time T1 (T_RRCQuick) elapses, P1, which is the transmission power level at which the RRC connection establishment message is first transmitted, At the same value, the RRC connection establishment message is repeatedly transmitted a set number of times N_RRCQuick. Next, if the RRC connection establishment complete message is not received such that T_RRCRe time elapses after the first RRC connection establishment message is transmitted, the RRC connection establishment message is transmitted with a P2 value in which the transmission power level is increased by RRCStepup as described above.

After that, the RRC connection establishment message repeatedly transmitted at the interval T1 is transmitted to the UE at the transmit power level of P2 value. If the RRC connection establishment complete message is not received until the T_RRCRe time elapses, the transmit power level set to P2 value is transmitted. Set to P3 increased by RRCStepup to transmit the RRC connection setup message. As described above, the RRC connection establishment message repeatedly transmitted at the T1 interval is repeatedly transmitted to the UE as many times as the number N_RRCQuick set to the transmit power level of the P3 value.

As described above, the mobile communication system and its RRC connection establishment method according to the present invention have been described with reference to the illustrated drawings, but the present invention is not limited to the embodiments and drawings disclosed herein, and after the transmission of the RRC connection establishment message. The technical concept of the present invention, which improves the reception success rate of the RRC connection establishment message to the terminal by increasing the transmission power and retransmitting the RRC connection establishment message after a certain time, can be easily applied by those skilled in the art within the scope of the claims. It can be obvious.

As described above, the mobile communication system and its RRC connection setting method according to the present invention repeatedly transmits the RRC connection setting message to the terminal so that the RRC connection setting process can be stably performed regardless of the change in the wireless environment. When retransmitting the connection establishment message, the RRC connection establishment message is retransmitted at a power level increased from the previous transmission power level, thereby greatly improving the reception success rate of the RRC connection establishment message at the terminal.

In addition, before the RRC connection establishment message is transmitted by increasing the transmission power level, the RRC connection establishment message may be repeatedly transmitted to the UE faster by transmitting the RRC connection establishment message in a shorter period. Accordingly, the RRC connection establishment is completed. By receiving messages faster, you can avoid unnecessary consumption of transmit power and have the advantage of completing the RRC connection process quickly.

Claims (9)

delete delete delete Receiving an RRC connection request message from a terminal; Repeatedly transmitting the RRC connection configuration message to the terminal at a first configuration time interval; And If the RRC setup complete message is not received from the terminal until a second setup time has elapsed, repeating the step of repeatedly transmitting the RRC connection setup message by increasing a transmission power level; In the step of repeatedly transmitting the RRC connection setup message, The number of repetitive transmissions of the RRC connection setup message is determined according to the first setup time and the second setup time. When a parameter value is set for repetitive transmission as many times as the repetitive transmission, and when the signal-to-noise ratio power (Eb / lo) value is lower than or equal to a predetermined value according to the set parameter value, when the received signal code power (RSCP) value is lower than or equal to a predetermined value, Or a case in which the repetitive transmission is performed in a case of always operating irrespective of a wireless channel environment. delete delete delete In the mobile communication system comprising a mobile communication terminal, and the RNC for transmitting and receiving data with the terminal, the RNC is A first timer for checking a first set time; A second timer for checking a second set time; And In response to the RRC connection request message received from the terminal, the RRC connection setting message is repeatedly transmitted to the terminal at the first setting time interval, and an RRC setting completion message is received from the terminal until the second setting time elapses. Otherwise, an RRC connection controller for re-transmitting the RRC connection establishment message at an increased transmission power level. Determine the number of repetitive transmissions of the RRC connection setup message according to the first setup time and the second setup time, When the signal-to-noise ratio power (Eb / lo) value is less than or equal to a predetermined value according to the parameter value set for repeated transmission by the number of times of repeated transmission, or when the received signal code power (RSCP) value is less than or equal to a predetermined value, or regardless of a wireless channel environment Mobile communication system, characterized in that to perform the repeated transmission to the case of always operating. delete

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