WO2014098409A1

WO2014098409A1 - Method and apparatus for supporting power preference of user equipment in consideration of qos

Info

Publication number: WO2014098409A1
Application number: PCT/KR2013/011487
Authority: WO
Inventors: 정명철; 권기범; 안재현
Original assignee: 주식회사 팬택
Priority date: 2012-12-20
Filing date: 2013-12-11
Publication date: 2014-06-26
Also published as: KR20140080200A

Abstract

The present invention relates to a method for supporting a power preference of user equipment in consideration of a quality of service (QoS) and an apparatus for same, and when the user equipment transmits to the base station a power preference indication (PPI) indicating a power preference state and a QoS preference indication (QPI) indicating a quality of service (QoS) preference state, the base station can reconfigure an RRC-related parameter with respect to the user equipment based on the power preference indication and the QoS preference indication. According to the present invention, the base station and the user equipment take into consideration the QoS preference of the user equipment and adaptively reconfigure the RRC-related parameter.

Description

Method and apparatus for supporting power preference of UE considering QOS

The present invention relates to wireless communication, and more particularly, to a method and apparatus for supporting power preference of a terminal in consideration of quality of service (QoS).

Due to the development of wireless communication technology, various terminals such as smart phones, tablets, and personal computers (PCs), which can use various applications and the like, are becoming popular. Accordingly, various applications used in the past over a wired network through a PC or the like are currently used in the same manner as a wired wired on a wireless network instead of a wired line, thereby generating various and a lot of traffic. However, in the case of a wireless network such as LTE (long term evolution), it is designed without sufficiently considering the traffic generation situation due to the use of the application in the current various terminals, the radio resources in the terminal performs wireless communication to the base station, An inefficient use of is occurring.

In addition, the terminal should be operated in consideration of power saving due to resource conditions such as limited battery. For this purpose, the terminal may use a discontinuous reception (DRX) method. In the case of using the DRX method, the terminal may be alternately operated by dividing into a non-active time and an active time. Therefore, the terminal or the base station may reduce the battery consumption of the terminal by a method such as longer inactivity time of the DRX method, depending on the type of application or traffic, or the battery saving needs of the terminal. On the other hand, depending on the type of application or traffic, the terminal or the base station may be required to maintain the maximum wireless data communication efficiency of the terminal by a method such as shortening the inactivity time of the DRX scheme. As such, a method for allowing the terminal and the base station to support the power preference of the terminal is required in order to adaptively set radio resources according to the situation of the terminal such as traffic type or battery state. In particular, there is a need for a method in which a terminal and a base station can support power preferences of a terminal in consideration of QoS required according to a service provided by the base station to the terminal.

An object of the present invention is to provide a method and apparatus for supporting power preference of a terminal.

Another technical problem of the present invention is to provide a method and apparatus for supporting a power preference of a terminal in consideration of QoS.

Another technical problem of the present invention is to provide a method and apparatus for performing radio resource configuration / reconfiguration based on whether to guarantee QoS in supporting power preference of a terminal.

Another technical problem of the present invention is to provide a structure of a UE Assistant Information (UE Assistant Information) message for supporting the power preference of the terminal in consideration of QoS.

Another technical problem of the present invention is to provide an information element (IE) for supporting power preference of a terminal in consideration of QoS.

Another technical problem of the present invention is to provide a method and apparatus for configuring radio resource control (RRC) parameters in consideration of QoS in supporting power preference of a terminal.

According to an aspect of the present invention, there is provided a method for supporting power preference of the terminal performed by the terminal. The method comprises receiving from the base station a first Radio Resource Control (RRC) Connection Reconfiguration message that includes power preference indicator-enabled information that allows the power preference indicator to be transmitted to the base station. Terminal assistance information including a power preference indicator (PPI) indicating a power preference state of the terminal and a QoS preference indicator (QPI) indicating a quality of service (QoS) preference state of the terminal; Generating and transmitting a message to the base station, and receiving a second RRC connection reconfiguration message from the base station, the second RRC connection reconfiguration message including an RRC related parameter reconfigured by the base station based on the power preference indicator and the QoS preference indicator; Characterized in that it comprises a step.

According to another aspect of the present invention, a method for supporting power preference of a terminal performed by a base station is provided. The method includes transmitting to the terminal a first RRC connection reconfiguration message including power preference indicator-enabled information allowing the transmission of a power preference indicator to a base station, the power preference indicator indicating a power preference state of the terminal; Receiving a terminal assistance information message including a QoS preference indicator indicating a QoS preference state of the terminal from the terminal, reconfiguring RRC related parameters based on the power preference indicator and the QoS preference indicator, and reconfiguring And transmitting a second RRC connection reconfiguration message including RRC related parameters to the terminal.

According to another aspect of the present invention, a terminal supporting power preference is provided. The terminal receives a first RRC connection reconfiguration message including power preference indicator-enabled information allowing the transmission of a power preference indicator to the base station from the base station, and determines the power preference state and QoS preference state of the terminal. A message processing unit for generating a terminal assistance information message including a preference determination unit, the power preference indicator indicating the power preference state and a QoS preference indicator indicating the QoS preference state, and transmitting the generated terminal assistance information message to the base station And a transmitting unit configured to receive a second RRC connection reconfiguration message including the RRC related parameters reconfigured by the base station based on the power preference indicator and the QoS preference indicator.

According to another aspect of the present invention, a base station supporting power preference of a terminal is provided. The base station transmits a first RRC connection reconfiguration message including power preference indicator-enabled information allowing the base station to transmit a power preference indicator to the base station, the power preference indicating a power preference state of the terminal. A parameter change unit configured to reconfigure RRC related parameters based on a receiver for receiving a terminal assistance information message from the terminal, the terminal assistance information message including an indicator and a QoS preference indicator indicating a QoS preference state of the terminal; And a message processing unit for generating a second RRC connection reconfiguration message including the reconfigured RRC related parameters, wherein the transmitter transmits the generated second RRC connection reconfiguration message to the terminal.

According to the present invention, the base station can not only inform the terminal by reconfiguring the RRC-related parameters based on the power preference of the terminal, the terminal can inform the base station of the preference for its QoS, the base station is the QoS of the terminal Check the preference for, and adaptively perform RRC-related parameter reconstruction. That is, the base station may support the terminal power preference in consideration of the terminal's preference for QoS guarantee.

In addition, when the need for power saving is large from the viewpoint of the terminal and the need for QoS is not large, by limiting or not supporting the QoS support for the service provided by the base station to the terminal for power saving, The efficiency can be improved.

1 shows a wireless communication system to which the present invention is applied.

2 shows a structure of a subframe to which the present invention is applied.

3 is a flowchart illustrating a procedure of transmitting a power preference indicator of a terminal according to an embodiment of the present invention.

4 is a flowchart illustrating a procedure of supporting power preference of a terminal according to an embodiment of the present invention.

5 is a conceptual diagram illustrating a DRX operation according to an embodiment of the present invention.

6 shows a structure of a bearer service in a wireless communication system to which the present invention is applied.

7 is a flowchart illustrating a power preference support procedure of a terminal considering QoS according to the present invention.

8 is a flowchart illustrating a method for supporting power preference of a terminal by a terminal according to an embodiment of the present invention.

9 is a flowchart illustrating a method for supporting power preference of a terminal by a base station according to an embodiment of the present invention.

FIG. 10 is a block diagram illustrating a terminal and a base station supporting power preference of another terminal according to an example of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In addition, in the following description of the embodiments of the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the subject matter of the present specification, the detailed description thereof will be omitted.

In addition, the present specification describes a wireless communication network, the operation performed in the wireless communication network is performed in the process of controlling the network and transmitting data in the system (for example, the base station) that is in charge of the wireless communication network, or the corresponding wireless Work may be done at the terminal coupled to the network.

Referring to FIG. 1, the wireless communication system 10 is widely deployed to provide various communication services such as voice and packet data. The wireless communication system 10 includes at least one base station 11 (evolved-NodeB, eNB). Each base station 11 provides a communication service for

specific cells

15a, 15b, and 15c. The cell can in turn be divided into a number of regions (called sectors). The base station 11 may be called by other terms such as a base station (BS), a base transceiver system (BTS), an access point, an femto base station, a home node B, a relay, and the like. A cell is meant to encompass all of the various coverage areas such as megacell, macrocell, microcell, picocell, femtocell, and the like.

The UE 12 may be fixed or mobile and may have a mobile station (MS), a mobile terminal (MS), a mobile terminal (MT), a user terminal (UT), a subscriber station (SS), a wireless device, or a PDA. (personal digital assistant), wireless modem (wireless modem), a handheld device (handheld device) may be called other terms.

Hereinafter, downlink refers to a transmission link from the base station 11 to the terminal 12, and uplink refers to a transmission link from the terminal 12 to the base station 11. it means. In downlink, the transmitter may be part of the base station 11 and the receiver may be part of the terminal 12. In uplink, the transmitter may be part of the terminal 12 and the receiver may be part of the base station 11. There is no limitation on the multiple access scheme applied to the wireless communication system. Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier-FDMA (SC-FDMA), OFDM-FDMA, OFDM-TDMA For example, various multiple access schemes such as OFDM-CDMA may be used. The uplink transmission and the downlink transmission may use a time division duplex (TDD) scheme that is transmitted using different times, or may use a frequency division duplex (FDD) scheme that is transmitted using different frequencies.

2 shows a structure of a subframe to which the present invention is applied.

Referring to FIG. 2, one radio frame includes 10 subframes, and one subframe includes two consecutive slots. The preceding 1, 2, 3 or 4 OFDM symbols of the first slot in the subframe are the control region to which the PDCCH is mapped, and the remaining OFDM symbols are mapped to the physical downlink shared channel (PDSCH). To become a data region. In addition to the PDCCH, the control region may be allocated a control channel such as PCFICH and PHICH. The UE may read data information transmitted through the PDSCH by decoding the PDCCH.

The UE is based on the PDCCH based on a cell-radio network temporary identifier (C-RNTI), transmission power control (TPC) -PUCCH-RNTI, TPC-PUSCH-RNTI and Semi Persistent Scheduling (RNS) -RNTI. Monitoring can be performed. Monitoring of the PDCCH may be controlled by a discontinuous reception (DRX) operation, the parameters for the DRX is transmitted by the base station to the terminal by the RRC message. In addition to the RNTIs, the terminal should always receive system information (SI) -RNTI, p (paging) -RNTI and the like regardless of the DRX operation configured by the RRC message. Here, the remaining PDCCHs except the PDCCH scrambled with C-RNTI are always received through a common search space of the main serving cell.

If the terminal has a DRX parameter configured in the RRC connected state, the terminal performs discontinuous monitoring on the PDCCH based on the DRX operation. On the other hand, if the DRX parameter is not configured, the UE monitors the continuous PDCCH. Discontinuous PDCCH monitoring may mean that the UE monitors the PDCCH only in a specific subframe, and continuous PDCCH monitoring may mean that the UE monitors the PDCCH in all subframes. On the other hand, if PDCCH monitoring is required in a DRX independent operation such as a random access procedure, the UE monitors the PDCCH according to the requirements of the corresponding operation.

The terminal should operate in consideration of power saving due to a limited battery such as a battery, and for this purpose, the terminal may use the DRX scheme or the like. In the case of using the DRX scheme, the terminal may be alternately operated by dividing into a non-active time and an active time. Therefore, the terminal or the base station may reduce the battery consumption of the terminal by a method such as longer inactivity time of the DRX method, depending on the type of application or traffic, or the battery saving needs of the terminal. On the other hand, depending on the type of application or traffic, the terminal or the base station may be required to maintain the maximum wireless data communication efficiency of the terminal by a method such as shortening the inactivity time of the DRX scheme. In order to adaptively set radio resources according to the situation of the terminal such as traffic type or battery state, a method capable of reflecting information on a preferred mode of the terminal between the terminal and the base station is required.

Referring to FIG. 3, the base station transmits an RRC connection reconfiguration message to the terminal (S300). The RRC connection reconfiguration message includes power PrefIndication-Enabled information and powerFrefIndication-Timer information. The power preference indicator-enabled information is information for allowing or instructing a terminal capable of transmitting a power preference indicator (PPI) to transmit the power preference indicator to a base station. The power preference indicator-timer information includes time information regarding a PPI prohibit timer. The PPI prohibit timer may indicate a minimum time interval (MTI) for the UE to transmit the power preference indicator. For example, the terminal sets the PPI prohibit timer based on the power preference indicator-timer, and when the terminal transmits a power preference indicator to the base station, operates the PPI prohibit timer, and again during the time that the PPI prohibit timer operates. It does not transmit power preference information of the terminal.

The terminal transmits a UE assistant information message to the base station (S310). The terminal assistance information message includes the power preference indicator. The terminal assistance information message is an RRC dedicated message.

The terminal may receive the power preference indicator-enabled information and transmit the power preference indicator to the base station by including the power preference indicator in the terminal assistance information. For example, the terminal may receive the power preference indicator-enabled information from the base station and transmit the power preference indicator to the base station when the PPI prohibit timer is not running. For example, the terminal may transmit the power preference indicator to the base station if the power preference indicator has not been transmitted to the base station even after being connected to the current serving cell. As another example, when the power preference state information finally transmitted to the base station is changed, the terminal may transmit a power preference indicator to the base station. As another example, the terminal may transmit a power preference indicator to the base station immediately when the PPI prohibit timer expires.

Here, the power preference indicator indicates the power preference state of the terminal. The power preference state of the terminal indicated by the power preference indicator includes, for example, a normal state (or a default state) and a low power consumption state.

The normal state (or default state) indicates that the terminal has no special preference. The normal state may indicate a state in which a terminal basically maintains a resource, a radio resource, a power consumption state, or a DRX state set in a network. In addition, the normal state may represent a state in which the current setting is maintained without considering specially the characteristics of the traffic. That is, the terminal in the normal state may be regarded as a state in which the basic state is maintained without a particularly preferred configuration. In addition, the normal state may be a state having a relatively high transmission efficiency compared to the low power consumption state described later. For example, even if the battery consumption is somewhat increased depending on the application used by the terminal, it may be regarded as a state requiring setting related to the base station in consideration of transmission efficiency.

The low power consumption state indicates that the terminal prefers low battery consumption. In other words, the low power consumption state may be regarded as a state in which the UE requires a related setting to reduce the battery consumption more than the current battery consumption state in order to minimize battery consumption. In this case, the base station may reconfigure the related configuration so that the terminal can reduce the battery consumption based on the information on the low power consumption state.

The base station may perform RRC related parameter reconfiguration by reflecting the power preference state of the terminal indicated by the power preference indicator of the terminal. Of course, the power preference of the terminal is a reference that the base station considers in configuring the radio resource, and the base station may perform RRC related parameter reconfiguration unlike the power preference of the terminal. The RRC related parameter to be reconfigured mainly corresponds to radio resource allocation and the like, but may include DRX parameters and the like, but is not limited thereto.

Referring to FIG. 4, since S400 and S410 are the same as those in S300 and S310 of FIG. 3, a detailed description thereof will be omitted.

The base station reconfigures an RRC related parameter, for example, a DRX related parameter, based on a power preference indicator of the terminal included in the terminal assistance information message received in S410, and transmits an RRC connection reconfiguration message including the same to the terminal (S420). ). Changing or reconfiguring RRC related parameters includes radio resource configuration or radio resource reconfiguration.

Here, DRX refers to a function that allows a UE to stop monitoring a downlink physical downlink control channel (PDCCH) for a predetermined period (eg, non-active time). In the DRX mode, the UE repeats an active time and a non-active time with a certain periodicity. Activity means that the UE monitors the PDCCH. Inactivity means that the UE stops monitoring the PDCCH.

The DRX may be configured by radio resource control / media access control (RRC / MAC). Related DRX parameters may include a long DRX cycle, a DRX Inactivity Timer, and a DRX Retransmission Timer. Also optionally, the DRX includes a short DRX cycle and a DRX Short Cycle Timer (drxShortCycleTimer). The long term DRX cycle provides longer inactivity time for the terminal than the short term DRX cycle.

Referring to FIG. 5, the DRX operation is repeated in units of DRX cycles 500. The DRX cycle 500 is a periodic repetition of an DRX opportunity (DR 510) and a duration (On Duration 505). Is defined. That is, one cycle of DRX cycle 500 includes a duration 505 and a DRX opportunity (DR) 510. The DRX cycle 500 includes, for example, a long DRX cycle applied in a range between 10 subframes and 2560 subframes, and another example is a short DRX cycle applied in a range of 2 subframes to 640 subframes. DRX cycle). At this time, the short term DRX cycle is applied only while the DRX short cycle timer (drxShortCycleTimer) is operating, and the long term DRX cycle is applied outside the DRX short cycle timer. Here, in the DRX short cycle timer, one short DRX cycle becomes a basic unit. At this time, the length of the short-term DRX cycle timer may be 1 to 16, for example. When the terminal is operating in the short-term DRX cycle may be referred to as a short-term DRX mode, when the terminal is operating in the long-term DRX cycle.

The RRC layer manages several timers to control the DRX operation. Timers controlling the DRX operation include a duration timer (onDurationTimer), a DRX inactivity timer (DRxInactivity Timer), a DRX retransmission timer (drxRetransmission Timer).

The duration timer is started by the start of the DRX cycle. In other words, the start of the duration timer coincides with the start of the DRX cycle. The duration timer increases by 1 for every PDCCH subframe. The duration timer expires when the duration timer value becomes equal to a preconfigured expiration value. The duration timer is valid until the duration timer value is equal to the expiration value.

The DRX inactivity timer may be defined as the number of consecutive PDCCH subframes from the time point of successfully decoding the PDCCH for uplink or downlink user data transmission. Since continuous data reception may occur, it is time for the UE to continuously monitor the PDCCH. The DRX Inactivity Timer is started or restarted when the UE successfully decodes the PDCCH for HARQ initial transmission in the PDCCH subframe.

The DRX retransmission timer is a timer that operates based on the maximum number of consecutive numbers of PDCCH subframes for which downlink retransmission is expected by the terminal soon. The DRX retransmission timer is a timer that is started when the retransmission data is not received even though the HARQ RTT timer has expired. The terminal may monitor the reception of data retransmitted in the HARQ process while the DRX retransmission timer is in progress. The configuration of the DRX retransmission timer is defined by the MAC-MainConfig message of the RRC layer.

The time that the duration timer, the DRX inactivity timer, or the DRX retransmission timer is in progress is called an active time. Alternatively, the activity time may mean all sections in which the terminal is awake. The non-active time of the DRX cycle 500 may be referred to as non-active time. The inactivity time may be called a wake up interval, and the inactivity time may be called a sleep interval. The UE monitors the PDCCH for the PDCCH subframe during the active time. Here, the PDCCH subframe means a subframe including the PDCCH. For example, in TDD configuration, downlink subframes and downlink pilot time slot (DwPTS) subframes correspond to PDCCH subframes. The timer unit of a DRX timer, such as a duration timer, a DRX inactivity timer, or a DRX retransmission timer, is a PDCCH subframe (psf). That is, DRX timers are counted based on the number of PDCCH subframes.

Other parameters to control DRX operation include long DRX cycle (longDRX-Cycle) and DRX start offset (drxStartOffset), and the base station optionally sets DRX short cycle timer (drxShortCycleTimer) and short DRX-cycle (shortDRX-Cycle). Can be. In addition, a HARQ round trip time (RTT) timer is defined for each downlink HARQ process.

The DRX start offset is a value that defines the subframe where the DRX cycle 500 begins. The DRX short cycle timer is a timer that defines the number of consecutive subframes that the UE must follow in the short DRX cycle. The HARQ RTT timer is a timer that defines the minimum number of subframes before the interval in which downlink HARQ retransmission is expected by the UE.

Meanwhile, the DRX configuration information may be received by being included in a MAC-MainConfig message, which is an RRC message used to specify a main configuration of a MAC layer for a signaling radio bearer (SRB) and a data radio bearer (DRB). DRX configuration information may be configured, for example, as shown in the table below.

Table 1

Referring to Table 1, the DRX configuration information includes an onDurationTimer field defining a value of a duration timer, a drx-InactivityTimer field indicating a value of a DRX inactivity timer, and a drx-RetransmissionTimer field indicating a value of a DRX retransmission timer. do. In addition, the DRX configuration information includes a longDRX-CycleStartOffset field indicating a length of a long DRX cycle and a starting subframe, and a shortDRX field regarding a short DRX that may be configured as optional. The shortDRX field specifically includes a shortDRX-Cycle subfield indicating the length of a short DRX cycle and a drxShortCycleTimer subfield indicating a value of a short term DRX cycle timer in which the UE is continuous.

The onDurationTimer field may be set to any one of {psf1, psf2, psf3, ... psf200}. psf means a PDCCH subframe, and the number after psf indicates the number of PDCCH subframes. That is, psf represents the expiration value of the timer as the number of PDCCH subframes. For example, if the onDurationTimer field = psf1, the duration timer expires after progressing up to one PDCCH subframe cumulatively including the subframe in which the DRX cycle is started. Or if the onDurationTimer field = psf4, the duration timer expires after progressing up to four PDCCH subframes cumulatively from the start of the DRX cycle. The drx-InactivityTimer field may be set to any one of {psf1, psf2, psf3, ... psf2560}. For example, if the drx-InactivityTimer field = psf3, the DRX Inactivity Timer progresses up to three PDCCH subframes cumulatively including the subframe at the time when it is driven and then expires. The drx-RetransmissionTimer field may be set to any one of {psf1, psf2, psf4, ... psf33}. For example, if the drx-RetransmissionTimer field = psf4, the DRX retransmission timer expires after progressing up to four PDCCH subframes including the subframe at the time when it is driven.

The longDRX-CycleStartOffset field may be set to any one of values of {sf10, sf20, sf32, sf40, ... sf2560} as the length of a long DRX cycle, and the subframe where the long DRX cycle starts is the length of the long DRX cycle. The value may be set to any one of {INTEGER (0..9), INTEGER (0..19), INTEGER (0..31), ... INTEGER (0..2559)}. For example, if the longDRX-CycleStartOffset field = sf20, INTEGER (0..19), one long DRX cycle includes 20 subframes, and the long DRX cycle includes any subframe of subframe indexes 0 to 19. This long term DRX cycle start subframe may be selected. The shortDRX-Cycle subfield constituting the shortDRX field may be set to any one of {sf2, sf5, sf8, ... sf640}. For example, if the shortDRX-Cycle subfield = sf5, one short DRX cycle includes 5 subframes. In addition, the drxShortCycleTimer subfield constituting the shortDRX field may indicate any one of integers 1 to 16. For example, if the drxShortCycleTimer subfield = 3, the short DRX cycle has gone through three times and then expires.

Referring back to FIG. 4, in step S420, the base station reconfigures the RRC related parameters, particularly the DRX related parameters based on the terminal preference information, and transmits them to the terminal. For example, the reconfiguration of the RRC related parameters may be performed as follows. have.

For example, when the power preference indicator indicates a normal state, the base station may maintain the RRC related parameter that has been previously configured. Therefore, in this case, S420 may be omitted. Alternatively, when the power preference indicator indicates a normal state, the base station may reconfigure RRC related parameters to increase transmission efficiency. For example, when the base station is configured only with long-term DRX, and the short-term DRX is not configured, the base station may perform DRX reconfiguration to add a short-term DRX configuration to the terminal to reflect the normal state. Alternatively, the base station determines the number of subframes (n) applied to one cycle of a long-term DRX or a short-term DRX (n) or less (x) (n = x or n <x: n is the number of DRX subframes and x is a subframe or more) Can be reconstructed. Alternatively, the base station may reconfigure the duration timer to a predetermined time or more (onDurationTimer = y or onDurationTimer> y). In addition, the base station may also reconfigure the DRX inactivity timer and DRX retransmission timer and the like for a predetermined time or more. Alternatively, the base station may reconfigure the number n of subframes applied to one cycle of the DRX by one step shorter than the conventional one, and may reconfigure the duration timer by one step longer than the conventional one. The base station may also reconfigure the DRX inactivity timer and the DRX retransmission timer to one step longer than before. In this case, the active time for the UE to monitor the PDCCH subframe occurs more frequently or longer, and the downlink transmission efficiency may be improved as compared with the case of the low power consumption state described later.

Specifically, in Table 1, when the onDurationTimer field = psf10 and the longDRX-CycleStartOffset field = sf40 and INTEGER (0..39), the base station powers the terminal based on the power preference indicator of the terminal. If it is found that the preference state is normal, the base station may reconfigure the onDurationTimer field = psf20. In addition, the base station may reconfigure the longDRX-CycleStartOffset field = sf32 and INTEGER (0..31). In addition, the base station may simultaneously reconfigure the onDurationTimer field = psf20, the longDRX-CycleStartOffset field = sf32, and INTEGER (0..31). In the above method, since the UE may operate more frequently in the active time due to the decrease in the DRX cycle length, and the UE may operate in the active time for a longer time due to the increase in the duration timer time. In this case, the transmission efficiency may be improved than in the case of the low power consumption state described later.

In general, when the power preference indicator indicates a normal state, the base station can give more scheduling opportunities in a relatively unit time for the terminal, thereby ensuring sufficient QoS to the terminal. Alternatively, the base station may support QoS for the terminal having a relatively short packet delay budget. This will be described later.

As another example, when the power preference indicator indicates a low power consumption state, the base station may perform RRC related parameter reconfiguration with a configuration that may reduce battery consumption of the terminal. For example, the base station reconfigures (or configures) DRX so that the terminal operates in a long-term DRX mode. Alternatively, the DRX may be reconfigured to maintain a longer inactivity time of the terminal. In this case, the base station may perform DRX reconfiguration so that the terminal does not operate in the short-term DRX mode, but operates in the long-term DRX mode. That is, when both the short term DRX and the long term DRX are configured in the DRX configuration, and the base station receives a power preference indicator indicating a low power consumption state from the terminal, the base station may remove the short term DRX configuration. Alternatively, the base station determines the number of subframes (n) applied to one cycle of the long-term DRX or the short-term DRX by more than a certain number (x) (n = x or n> x: n is the number of DRX subframes and x is a subframe or more) Can be reconstructed. In addition, the base station may reconfigure the duration timer to a predetermined time (y) or less (onDurationTimer = y or onDurationTimer <y). In addition, the base station may also reconfigure the DRX inactivity timer and DRX retransmission timer and the like to a predetermined time or less. Alternatively, the base station may reconfigure the number n of subframes applied to one cycle of the DRX to a value one step longer than before and may reconfigure the duration timer to one step shorter than before. The base station may also reconfigure the DRX inactivity timer and the DRX retransmission timer to one step shorter than before. In this case, when the number of subframes applied to one DRX cycle increases, the cycle for monitoring the PDCCH by the UE becomes long, thereby reducing power consumption of the UE. In addition, since the duration timer, the DRX inactivity timer, and the DRX retransmission timer are related to the number of times of reception of the PDCCH subframe, reconfiguring them into less time may have an effect in terms of power saving of the UE. Can be.

Specifically, in Table 1, when the onDurationTimer field = psf10, and the longDRX-CycleStartOffset field = sf40, INTEGER (0..39), the base station is low on the basis of the power preference information of the terminal If it is found that the power consumption state, the base station may reconfigure the onDurationTimer field = psf8. In addition, the base station may reconfigure the longDRX-CycleStartOffset field = sf64 and INTEGER (0..63). In addition, the base station may simultaneously reconfigure the onDurationTimer field = psf8 and the longDRX-CycleStartOffset field = sf64 and INTEGER (0..63). In the above method, since the terminal may operate in an intermittent more active time due to an increase in the DRX cycle length, and the terminal may operate in an active time for a shorter time due to a decrease in duration timer time. The terminal may reduce power consumption.

As described above, the terminal may transmit power preference information of the terminal to the base station, and the base station may reconfigure the RRC related parameters in the terminal in consideration of the power preference state of the terminal based on the power preference information. However, in terms of the base station, when the terminal performs the RRC related parameter reconfiguration according to the transmitted power preference information, the base station may not satisfy the QoS required by the service provided to the terminal. For example, when the power preference state of the terminal is a low power consumption state, or when the base station reconfigures the RRC related parameters based on the low power consumption state, the base station reconfigures (or configures) DRX to operate in a long-term DRX mode. do or. Alternatively, because the DRX is reconfigured so that the inactivity time of the terminal is maintained longer, it may be difficult to satisfy the QoS for the service provided by the base station to the terminal due to a scheduling delay.

In general, the base station manages QoS through QCI mapping to bearers, and in the wireless communication system to which the present invention is applied, the bearers may be configured as follows.

Referring to FIG. 6, bearers provided by the wireless communication system are collectively referred to as EPS (Evolved Packet System) bearers. The EPS bearer is a transmission path generated between the UE and the P-GW.

EPS bearer types include a default bearer and a dedicated bearer. When the terminal accesses the wireless communication network, an IP address is assigned and a default EPS bearer is created while creating a PDN connection. That is, a default bearer is first created when a new PDN connection is created. The default bearer remains until the PDN connection is terminated. When a user uses a service (for example, the Internet, etc.) through a default bearer, and uses a service (for example, VoD, etc.) that the default bearer cannot provide QoS properly, the user may be on-demand. A dedicated bearer is created. In this case, the dedicated bearer may be set to a different QoS from the bearer that is already set. QoS parameters applied to the dedicated bearer are provided by a Policy and Charging Rule Function (PCRF). Upon creation of the dedicated bearer, the PCRF may receive the subscription information of the user from the Subscriber Profile Repository (SPR) to determine the QoS parameter. Up to 15 dedicated bearers may be created, for example, and four of the 15 are not currently used in LTE systems. Therefore, up to 11 dedicated bearers can be created.

The EPS bearer includes a QoS Class Identifier (QCI) and an Allocation and Retention Priority (ARP) as basic QoS parameters. QCI is a scalar that is used as a reference to access node-specific parameters that control bearer level packet forwarding treatment, and the scalar value is assigned to an operator owning a base station. Pre-configured by For example, the scalar may be preconfigured with any one of integer values 1 to 9. The main purpose of ARP is to determine whether a bearer's establishment / modification request is accepted or needs to be rejected in case of resource limitations. ARP can also be used to determine which bearer (s) to drop by the base station during exceptional resource limitations, for example at handover.

EPS bearers are divided into GBR (Guaranteed Bit Rate) bearers and non-GBR bearers. The default bearer is always a non-GBR type bearer, and the dedicated bearer may be a GBR type or non-GBR type bearer.

In addition to QCI and ARP, the GBR bearer is further associated with a guaranteed bit rate (GBR) and a maximum bit rate (MBR) as QoS parameters. The GBR notes a bit rate that can be expected to be provided by the EPS bearer. The MBR limits the bit rate that can be expected to be provided by the EPS bearer. In other words, the GBR may indicate information about a bit rate that should be guaranteed at least, and the MBR may indicate information about a maximum bit rate allowance in order to prevent excessive use of resources when the bit rate guaranteed by the GBR is acceptable. That is, the GBR bearer may mean that fixed resources are allocated for each bearer (bandwidth guarantee).

On the other hand, non-GBR bearers are associated with Aggregated Maximum Bit Rate (AMBR) as a QoS parameter in addition to QCI and ARP, which means that the maximum number that can be used with other non-GBR bearers instead of being allocated resources per bearer. This means that bandwidth is allocated. In other words, AMBR may define an aggregate bit rate that can be expected to be provided for a non-GBR bearer. That is, the AMBR may indicate information on the maximum bandwidth that can be allocated for the non-GBR bearer.

P-GW (Packet Gateway) is a network node connecting between a wireless communication network (for example, LTE network) and another network according to the present invention. EPS bearer is defined between the terminal and the P-GW. EPS bearer is further subdivided between nodes, defined as RB between UE and BS, S1 bearer between BS and S-GW, and S5 / S8 bearer between S-GW and P-GW in EPC. do. Each bearer is defined through QoS. QoS is defined through data rate, error rate, delay, and the like.

Therefore, once the QoS that the wireless communication system should provide as a whole is defined as an EPS bearer, each QoS is determined for each interface. Each interface establishes a bearer according to the QoS that it must provide.

Since bearers of each interface provide QoS of all EPS bearers by interface, EPS bearers, RBs, and S1 bearers are all in a one-to-one relationship.

Table 2 shows the QCI table representing the characteristics of QoS classes. The base station may allocate a QCI in a bearer establishment or modification procedure and check the same.

TABLE 2

Referring to Table 2, the Packet Delay Budget (PDB) represents the upper bound of the allowable delay time for the corresponding QCI, and the PELR represents the allowable Packet Error Loss Rate of the corresponding QCI. The upper limit is shown.

QoS assigned to the bearer is managed by QCI and managed according to each characteristic of QCI index 1 to 9. For example, bearers with QoS corresponding to QCI indexes 6, 8, and 9 have a packet delay budget of 300 ms, which is used for a relatively large service, and a resource type of non-GBR. Bearers having QoS corresponding to QCI index 4 have a packet delay budget of 300 ms and a relatively large value, but have a resource type of GBR.

In the current wireless communication system as described above, in providing a service to a terminal, the base station should be able to support QoS required by the corresponding service. This is generally the case even when the base station receives power preference information from the terminal and performs RRC related parameter reconfiguration based on the power preference state of the terminal. Therefore, when the power preference state of the terminal is a low power consumption state, when the necessity of battery saving is large from the viewpoint of the terminal, or when the packet delay budget is relatively small, such as when the QCI index for the service provided to the terminal is 5, the base station From the standpoint, the RRC-related parameter reconstruction may not be performed by reflecting a low power consumption state of the terminal. This is because the base station needs to provide and maintain the QoS provided to the terminal. However, in certain cases, for example, when the necessity of power saving is large from the standpoint of the terminal and the necessity of QoS satisfaction is not large, the terminal does not limit or support QoS support for a service provided by the base station to the terminal for power saving. There is a need to allow not to. For example, the terminal may be in a temporary battery problem or a limited power situation, and the terminal may identify the situation and allow continuous or temporary limitation of QoS for power saving. However, in the current wireless communication system, the base station can only check the power preference state of the terminal through the power preference information provided by the terminal, and further, if the terminal allows a certain degree of QoS, or in certain cases, further power saving. Priority information cannot be confirmed by the base station whether the base station requests to ignore the QoS required by the corresponding QCI. Therefore, in supporting terminal power preferences in a base station and a terminal, a method of considering a terminal's preference for QoS for a service provided by the base station to the terminal is required.

Hereinafter, the UE power preference support procedure considering QoS according to the present invention may be performed as follows.

7 is a flowchart illustrating a power preference support procedure of a terminal considering QoS according to an embodiment of the present invention.

Referring to FIG. 7, the base station transmits an RRC connection reconfiguration message to the terminal (S700). The RRC connection reconfiguration message includes power preference indicator-enabled information and power preference indicator-timer information. The power preference indicator-enabled information is information for allowing or instructing a terminal capable of transmitting a power preference indicator to transmit the power preference indicator to a base station. The power preference indicator-timer information includes time information regarding a power preference indicator prohibit timer. The PPI prohibit timer may indicate a minimum time interval for the terminal to transmit the power preference indicator.

The terminal transmits a terminal assistance information message to the base station (S710). The terminal assistance information message includes a power preference indicator. The terminal assistance information message is an RRC only message. In addition, the terminal assistance information message may include a QoS Preference Indication (QPI). The QoS preference indicator may be included with the power preference indicator when the terminal assistance information message includes the power preference indicator, or the QoS preference indicator may be low in the power preference state of the terminal indicated by the power preference indicator. It may optionally be included only when it is in a power consumption state. The QoS preference indicator indicates a terminal's preference for QoS, and the base station may reconfigure RRC related parameters in the terminal in consideration of both the power preference indicator and the QoS preference indicator. The QoS preference indicator may be referred to as QoS information (QoSinfo), QoS priority information (QoSPriorityInfo), or QoS hold (QoSHold).

For example, the QoS preference indicator may instruct the packet delay budget to guarantee the QoS of the bearer corresponding to the QCI below or below a certain level. In other words, if the packet delay budget of the QCI for the bearer is below (or below) a certain level, even if the UE's power preference state is low power consumption, the base station is based on the QoS preference indicator to provide a low QoS guarantee. RRC-related parameter reconfiguration according to the power consumption may not be performed. Specifically, for example, if the QoS affinity indicator indicates support or value 1, QCI index 1 that does not correspond to QCI indexes 4, 6, 8, and 9 with a packet delay budget of 300 ms or more for the bearer. , 2, 3, 5, and 7 can be seen that the packet delay budget is less than 300ms, the base station does not reconstruct the RRC-related parameters based on the low power consumption state to guarantee QoS to the terminal, or Performs RRC related parameter reconstruction based. In addition, when the QoS preference indicator indicates no support or a value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state regardless of the packet delay budget of the QCI for the bearer. For example, even when there is a bearer corresponding to

QCI indexes

1, 2, 3, 5, and 7 having a packet delay of 300 ms or less, RRC-related parameter reconstruction based on a low power consumption state may be performed. At this time, if the base station performs reconfiguration of the RRC parameter based on the low power consumption state, it may not be able to guarantee QoS for the

QCI indexes

1,2,3,5,7. However, in this case, the UE may determine that low power consumption is given priority over whether QoS is guaranteed and may perform the RRC parameter reconfiguration.

As another example, the QoS preference indicator may indicate to guarantee the QoS of the bearer corresponding to the QCI whose resource type is GBR. In other words, when the resource type of the QCI for the bearer is GBR, the base station may guarantee QoS and may not perform RRC related parameter reconfiguration or RRC related parameter reconfiguration. Specifically, for example, if the QoS affinity indicator indicates support or a value of 1, when the QCI for the bearer is a GBR type bearer with 1, 2, 3, or 4, the base station guarantees QoS for the bearer, and for the bearer In the case of a non-GBR bearer having a QCI of 5, 6, 7, 8, or 9, RRC-related parameter reconfiguration based on low power consumption may be performed regardless of QoS. In addition, when the QoS preference indicator indicates no support or a value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state without guaranteeing QoS for the bearer. That is, even for a GBR bearer, radio resource reconfiguration may be performed based on a low power consumption state without guaranteeing QoS. Or it may be set to the opposite case by the appointment between the terminal and the base station.

As another example, the QoS preference indicator may indicate whether a QoS guarantee is reserved (or violated). In other words, the QoS preference indicator may indicate whether or not the base station guarantees QoS in providing a service to the terminal. Specifically, for example, if the QoS preference indicator indicates no support or a value of 0, the base station may ignore the QoS for the bearer and perform RRC related parameter reconfiguration based on a low power consumption state. In addition, if the QoS preference indicator indicates support or a value of 1, the base station performs RRC related parameter reconfiguration based on low power consumption state or does not perform RRC related parameter reconfiguration based on low power consumption state while guaranteeing QoS for the bearer. Or RRC related parameter reconstruction based on the normal state.

Of course, the above-described

values

0 and 1 mean that the QoS preference state of the UE can be represented by setting the opposite direction by the base station and the UE.

The terminal assistance information message including the power preference indicator and the QoS preference indicator may be configured as a syntax as shown in Table 3, for example.

TABLE 3

Referring to Table 3, the terminal assistance information message includes a powerPrefIndication-r11 information element (IE). The powerPrefIndication-r11 information element is used to provide information related to the power preference of the terminal, that is, the power saving preference of the terminal. The powerPrefIndication-r11 information element may be configured as shown in Table 4, for example.

Table 4

Referring to Table 4, the powerPrefIndication-r11 information element includes a PowerConsumptionPref field and a QoSInfoindication field. The PowerConsumptionPref field is a power preference indicator of the terminal, which indicates a power preference state of the terminal, and may indicate a normal state and a low power consumption state. The QoSInfoindication field is a QoS preference indicator of the terminal, and may indicate a preference state of the terminal with respect to QoS guarantee (or QoS violation) according to a setup value.

For example, the packet delay budget may be instructed to guarantee the QoS of the bearer corresponding to the QCI below (or below) a certain level. Specifically, for example, if the QoS preference indicator indicates a setup value of 1,

QCI indexes

1, 2, and 3 that do not correspond to QCI indexes 4, 6, 8, and 9 whose packet delay budget for the bearer is 300 ms or more. If the packet delay budget is less than 300ms, the base station does not reconfigure the RRC related parameters based on the low power consumption state to guarantee QoS to the UE or reconfigure the RRC related parameters based on the normal state. Do this. In addition, when the QoS preference indicator indicates a setup value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state regardless of the packet delay budget of the QCI for the bearer.

As another example, it may be indicated to guarantee QoS of a bearer corresponding to QCI whose resource type is GBR. Specifically, for example, when the QoS preference indicator indicates a setup value of 1, when the QCI for the bearer is a GBR type bearer having 1, 2, 3, or 4, the base station guarantees QoS for the bearer, and the QCI for the bearer. Is a non-GBR type bearer having 5, 6, 7, 8 or 9, RRC related parameter reconfiguration based on low power consumption may be performed regardless of QoS. In addition, when the QoS preference indicator indicates a setup value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state without guaranteeing QoS for the bearer. That is, even for a GBR bearer, radio resource reconfiguration may be performed based on a low power consumption state without guaranteeing QoS.

As another example, the QoS guarantee may be indicated. Specifically, for example, if the QoS preference indicator indicates a setup value of 0, the base station may ignore the QoS for the bearer and perform RRC related parameter reconfiguration based on a low power consumption state. In addition, if the QoS preference indicator indicates a setup value of 1, the base station performs RRC related parameter reconfiguration based on low power consumption state or no RRC related parameter reconfiguration based on low power consumption state while guaranteeing QoS for the bearer. RRC related parameter reconstruction based on the normal state may be performed.

The above-mentioned QoSInfoindication field may indicate a preference state of the UE for QoS guarantee only when the PowerConsumptionPref field is in a low power consumption state. The QoSInfoindication field may be replaced with another term such as QoSInfoPref, QoSGuaranteePref, or QoSSupportPref by an appointment between the terminal and the base station. Same as below.

Meanwhile, the terminal assistance information message including the power preference indicator and the QoS preference indicator may be configured as a syntax of Table 5 as another example.

Table 5

Referring to Table 5, the terminal assistance information message includes a powerPrefIndication-r11 information element and a qosInfoindication-r11 information element. The powerPrefIndication-r11 information element is used to provide information related to the power preference of the terminal, that is, the power saving preference of the terminal. The qosInfoindication-r11 information element may always be present if the powerPrefIndication-r11 information element is present, and the qosInfoindication-r11 information element may be optionally present only when the PowerConsumptionPref field included in the powerPrefIndication-r11 information element indicates low power consumption. It may be.

The powerPrefIndication-r11 information element may be configured as shown in Table 6, for example.

Table 6

Referring to Table 6, the powerPrefIndication-r11 information element includes a PowerConsumptionPref field. The PowerConsumptionPref field is a power preference indicator of the terminal, which indicates a power preference state of the terminal, and may indicate a normal state and a low power consumption state.

In addition, the qosInfoindication-r11 information element may be configured as shown in Table 7, for example.

TABLE 7

Referring to Table 7, the qosInfoindication-r11 information element includes a QoSInfoindication field. The QoSInfoindication field is a QoS preference indicator of the UE and indicates the UE's preference state for QoS guarantee according to the setup value. The QoSInfoindication field may indicate a preference state of the terminal for QoS guarantee only when the PowerConsumptionPref field is in a low power consumption state. As described above, the QoSInfoindication field is a QoS preference indicator of the UE. For example, the QoSInfoindication field may indicate that a packet delay budget guarantees QoS of a bearer corresponding to a QCI of a predetermined level or less (or less). As another example, it may be indicated to guarantee QoS of a bearer corresponding to QCI whose resource type is GBR. As another example, the QoS guarantee may be indicated.

Referring to FIG. 7 again, the base station reconfigures an RRC related parameter, for example, a DRX related parameter, based on the terminal assistance information message received in S710, and transmits an RRC connection reconfiguration message including the same to the terminal (S720). .

The terminal assistance information message includes a power preference indicator. Based on the power preference indicator, the base station reconfigures RRC related parameters including DRX related parameters and the like corresponding to the power preference state of the terminal indicated by the power preference indicator of the terminal, and reconfigures the RRC connection transmitted by the base station to the terminal. It can be transmitted to the terminal through a message. In this case, the DRX related parameter reconstruction includes the contents described in S420.

In addition, the terminal assistance information message may include a QoS Preference Indication (QPI). The QoS preference indicator may be included together with the power preference indicator when the terminal assistance information message includes the power preference indicator as described above, or the QoS preference indicator is the power of the terminal indicated by the power preference indicator. It may be selectively included only when the preference state is a low power consumption state. The base station may reconfigure the RRC related parameters in the terminal in consideration of both the power preference indicator and the QoS preference indicator.

For example, when only the power preference indicator is included in the terminal assistance information message and the QoS preference indicator is not included, the base station determines an RRC related parameter including a DRX related parameter based on the power preference indicator. The power preference indicator of the terminal may be reconfigured according to the power preference state indicated by the terminal, and may be transmitted to the terminal through an RRC connection reconfiguration message transmitted by the base station to the terminal. However, when the power preference indicator is not included as described above, the QoS guarantee may be set to be prioritized by an appointment of the terminal and the base station, and the base station may reconfigure the RRC related parameters only within the scope of the QoS guarantee. Alternatively, when the power preference indicator is not included as described above, QoS guarantee may be ignored by appointment of the terminal and the base station, and the power preference state of the terminal indicated by the power preference indicator may be set to take priority. RRC related parameters may be reconfigured according to the preference state.

Further, for example, when the terminal assistance information message includes both the power preference indicator and the QoS preference indicator, and the power preference indicator indicates a low power consumption state, the base station is in a state indicated by the QoS preference indicator. RRC-related parameters may be reconfigured correspondingly.

For example, when the state indicated by the QoS preference indicator indicates the guarantee of QoS of the bearer corresponding to the QCI whose packet delay budget is below (or below) a certain level, the base station determines that the power preference state of the terminal is low power consumption. Nevertheless, based on the QoS preference indicator, RRC-related parameter reconfiguration according to the low power consumption state may not be performed to guarantee QoS. Specifically, for example, when the QoS preference indicator indicates 1,

QCI indexes

1, 2, 3, 5, and 7 that do not correspond to QCI indexes 4, 6, 8, and 9 whose packet delay budgets for the bearer are 300 ms or more. If it is determined that the packet delay budget is less than 300ms, the base station does not perform RRC related parameter reconfiguration based on the low power consumption state or performs RRC related parameter reconfiguration based on the normal state to guarantee QoS to the UE. In addition, when the QoS preference indicator indicates 0, the base station may perform RRC related parameter reconfiguration based on the low power consumption state regardless of the packet delay budget of the QCI for the bearer.

As another example, when the state indicated by the QoS preference indicator indicates to guarantee the QoS of the bearer corresponding to the QCI whose resource type is GBR, the base station guarantees the QoS to perform RRC related parameter reconfiguration or RRC related parameter reconfiguration. You can't. Specifically, for example, when the QoS preference indicator indicates 1, when the QBR for the bearer is a GBR type bearer having 1, 2, 3, or 4, the base station guarantees QoS for the bearer, and the QCI for the bearer is 5 In the case of a non-GBR bearer of 6, 7, 8, or 9, RRC related parameter reconfiguration based on low power consumption may be performed regardless of QoS. In addition, when the QoS preference indicator indicates 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state without guaranteeing QoS for the bearer. That is, even for a GBR bearer, radio resource reconfiguration may be performed based on a low power consumption state without guaranteeing QoS. Or it may be set to the opposite case by the appointment between the terminal and the base station.

As another example, when the status indicated by the QoS preference indicator indicates whether the QoS guarantee is reserved (or violated), that is, the status indicated by the QoS preference indicator indicates that the base station provides the service to the terminal. Or base station does not perform RRC related parameter reconstruction based on the low power consumption state, prioritizing the QoS guarantee, or ignores the QoS guarantee, and performs RRC related based on low power consumption state. Parameter reconstruction can be performed. Specifically, for example, if the QoS preference indicator indicates 1, the base station may ignore the QoS for the bearer and perform RRC related parameter reconfiguration based on the low power consumption state. In addition, if the QoS preference indicator indicates 0, the base station performs RRC related parameter reconfiguration based on low power consumption state or does not perform RRC related parameter reconfiguration based on low power consumption state or normal state while guaranteeing QoS for bearer. RRC-related parameter reconstruction based on may be performed.

The base station transmits the reconfigured RRC related parameters to the terminal through an RRC connection reconfiguration message.

According to the present invention as described above, the base station can not only inform the terminal by reconfiguring the RRC-related parameters based on the power preference of the terminal, the terminal can inform the base station of the preference for its QoS, the base station is The preference of the QoS of the UE may be checked, and RRC-related parameter reconfiguration may be adaptively performed. That is, the base station may support the terminal power preference in consideration of the terminal's preference for QoS guarantee. In particular, when the necessity of power saving is large from the viewpoint of the terminal and the necessity of QoS is not large, the efficiency of power saving is allowed by limiting or not supporting QoS support for the service provided by the base station to the terminal for power saving. Can increase.

Referring to FIG. 8, the terminal receives an RRC connection reconfiguration message from the base station (S800). The RRC connection reconfiguration message includes power preference indicator-enabled information and power preference indicator-timer information. The power preference indicator-enabled information is information for allowing or instructing a terminal capable of transmitting a power preference indicator to transmit the power preference indicator to a base station. The power preference indicator-timer information includes time information regarding a power preference indicator prohibit timer. The PPI prohibit timer may indicate a minimum time interval for the terminal to transmit the power preference indicator. For example, when the PPI prohibit timer is set to 5 minutes based on the power preference indicator-timer, the terminal may transmit the power preference indicator at least 5 minutes. In other words, after transmitting the power preference indicator, the terminal sets and operates the PPI prohibit timer based on the power preference indicator-timer and cannot transmit the power preference information of the terminal again during the operation of the PPI prohibit timer. This may be the same even when the power preference state of the terminal is changed.

The terminal transmits a terminal assistance information message to the base station (S810). The terminal assistance information message includes a power preference indicator. The terminal assistance information message may be an RRC dedicated message. In addition, the terminal assistance information message may include a QoS preference indicator. The QoS preference indicator may be included with the power preference indicator when the terminal assistance information message includes the power preference indicator, or the QoS preference indicator may be low in the power preference state of the terminal indicated by the power preference indicator. It may optionally be included only when it is in a power consumption state. The QoS preference indicator indicates the terminal's preference for QoS. The terminal assistance information message may be configured by, for example, a syntax as shown in Table 3 below. In this case, the power preference indicator and QoS preference indicator may be configured as shown in Table 4. In addition, the terminal assistance information message may be configured as a syntax of Table 5 as another example. In this case, the power preference indicator may be configured as shown in Table 6, and the QoS preference indicator may be configured as shown in Table 7.

The terminal receives an RRC connection reconfiguration message from the base station (S820). The RRC connection message may include an RRC related parameter reconfigured by the base station based on the terminal assistance information, for example, a DRX related parameter. The DRX related parameter reconstruction includes the contents described in S420. The terminal may reconfigure the RRC related parameters received through the RRC connection reconfiguration message to the terminal.

9, the base station transmits an RRC connection reconfiguration message to the terminal (S900). The RRC connection reconfiguration message includes power preference indicator-enabled information and power preference indicator-timer information. The power preference indicator-enabled information is information for allowing or instructing a terminal capable of transmitting a power preference indicator to transmit the power preference indicator to a base station. The power preference indicator-timer information includes time information regarding a power preference indicator prohibit timer. The PPI prohibit timer may indicate a minimum time interval for the terminal to transmit the power preference indicator.

The base station receives a terminal assistance information message from the terminal (S910). The terminal assistance information message includes a power preference indicator. The terminal assistance information message is an RRC only message. In addition, the terminal assistance information message may include a QoS preference indicator. The QoS preference indicator may be included with the power preference indicator when the terminal assistance information message includes the power preference indicator, or the QoS preference indicator may be low in the power preference state of the terminal indicated by the power preference indicator. It may optionally be included only when it is in a power consumption state. The QoS preference indicator indicates the terminal's preference for QoS. The terminal assistance information message may be configured by, for example, a syntax as shown in Table 3 below. In this case, the power preference indicator and QoS preference indicator may be configured as shown in Table 4. In addition, the terminal assistance information message may be configured as a syntax of Table 5 as another example. In this case, the power preference indicator may be configured as shown in Table 6, and the QoS preference indicator may be configured as shown in Table 7.

The base station reconfigures an RRC related parameter, for example, a DRX related parameter, based on the terminal assistance information message received in S910, and transmits an RRC connection reconfiguration message including the same to the terminal (S920).

For example, when only the power preference indicator is included in the terminal assistance information message and the QoS preference indicator is not included, the base station determines an RRC related parameter including a DRX related parameter based on the power preference indicator. The power preference indicator of the terminal may be reconfigured according to the power preference state indicated by the terminal, and may be transmitted to the terminal through an RRC connection reconfiguration message transmitted by the base station to the terminal. However, when the power preference indicator is not included as described above, the QoS guarantee may be set to be prioritized by an appointment of the terminal and the base station, and the base station may reconfigure the RRC related parameters only within the scope of the QoS guarantee. Alternatively, when the power preference indicator is not included as described above, QoS guarantee may be ignored by appointment of the terminal and the base station, and the power preference state of the terminal indicated by the power preference indicator may be set to take priority, and the base station may set the power. RRC related parameters may be reconfigured according to the preference state.

For example, when the state indicated by the QoS preference indicator indicates the guarantee of QoS of the bearer corresponding to the QCI whose packet delay budget is below (or below) a certain level, the base station determines that the power preference state of the terminal is low power consumption. Nevertheless, based on the QoS preference indicator, RRC-related parameter reconfiguration according to the low power consumption state may not be performed to guarantee QoS. Specifically, for example, if the QoS affinity indicator indicates support or a value of 1,

QCI indexes

1, 2, 3, 5 that do not correspond to QCI indexes 4, 6, 8, and 9 with a packet delay budget of 300 ms or more for the bearer. If the packet delay budget is less than 300ms, the base station does not reconfigure the RRC related parameters based on the low power consumption state or performs the RRC related parameters reconfigured based on the normal state in order to guarantee QoS to the UE. do. In addition, when the QoS preference indicator indicates no support or a value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state regardless of the packet delay budget of the QCI for the bearer.

As another example, when the state indicated by the QoS preference indicator indicates to guarantee the QoS of the bearer corresponding to the QCI whose resource type is GBR, the base station guarantees the QoS to perform RRC related parameter reconfiguration or RRC related parameter reconfiguration. You can't. Specifically, for example, if the QoS affinity indicator indicates support or a value of 1, when the QCI for the bearer is a GBR type bearer with 1, 2, 3, or 4, the base station guarantees QoS for the bearer, and for the bearer In the case of a non-GBR bearer having a QCI of 5, 6, 7, 8, or 9, RRC-related parameter reconfiguration based on low power consumption may be performed regardless of QoS. In addition, when the QoS preference indicator indicates no support or a value of 0, the base station may perform RRC related parameter reconfiguration based on a low power consumption state without guaranteeing QoS for the bearer. That is, even for a GBR bearer, RRC-related parameter reconfiguration may be performed based on a low power consumption state without guaranteeing QoS. Or it may be set to the opposite case by the appointment between the terminal and the base station.

As another example, when the status indicated by the QoS preference indicator indicates whether the QoS guarantee is reserved (or violated), that is, the status indicated by the QoS preference indicator indicates that the base station provides the service to the terminal. Or base station does not perform RRC related parameter reconstruction based on the low power consumption state, prioritizing the QoS guarantee, or ignores the QoS guarantee, and performs RRC related based on low power consumption state. Parameter reconstruction can be performed. Specifically, for example, if the QoS preference indicator indicates no support or a value of 0, the base station may ignore the QoS for the bearer and perform RRC related parameter reconfiguration based on a low power consumption state. In addition, if the QoS preference indicator indicates support or a value of 1, the base station performs RRC related parameter reconfiguration based on low power consumption state or does not perform RRC related parameter reconfiguration based on low power consumption state while guaranteeing QoS for the bearer. Or RRC related parameter reconstruction based on the normal state.

The base station transmits the reconfigured RRC related parameters to the terminal through an RRC connection reconfiguration message. In this case, the base station may reconfigure the RRC-related parameters in consideration of the power preference of the terminal as well as the QoS preference of the terminal, and may transmit it to the terminal through an RRC connection reconfiguration message.

Referring to FIG. 10, the terminal 1000 includes a terminal receiver 1005, a terminal processor 1010, and a terminal transmitter 1015. The terminal processor 1010 includes a terminal message processor 1011 and a preference determiner 1012.

The terminal receiving unit 1005 receives power preference indicator-enabled information, power preference indicator-timer information, and RRC related parameters from the base station 1050 from the base station.

The power preference indicator-enabled information is information for allowing or instructing a terminal capable of transmitting a power preference indicator (PPI) to transmit the power preference indicator to a base station. The power preference indicator-timer information includes time information regarding a PPI prohibit timer. The PPI prohibit timer may indicate a minimum time interval for the terminal to transmit the power preference indicator. The power preference indicator-enabled information and the power preference indicator-timer information may be included in an RRC connection reconfiguration message and transmitted from the base station 1050 to the terminal 1000.

The RRC-related parameter may be a parameter reconfigured by the base station 1050 based on the power preference indicator of the terminal 1000. The RRC related parameter may include a DRX related parameter. The RRC related parameter may be included in an RRC connection reconfiguration message and transmitted from the base station 1050 to the terminal 1000.

The terminal message processing unit 1011 analyzes or interprets the syntax of the information or the message received from the terminal receiving unit 1005. The terminal message processing unit 1011 may interpret the syntax of Table 1.

The terminal message processing unit 1011 interprets the received RRC connection reconfiguration message and confirms that the power preference indicator transmission of the terminal 1000 is allowed or commanded based on the power preference indicator-enabled information included in the message. In addition, the message processing unit 1011 sets the time of the PPI prohibit timer of the terminal based on the power preference indicator-timer information included in the message. In addition, the terminal message processing unit 1011 may interpret the RRC connection reconfiguration message and obtain RRC related parameters. The RRC related parameter may be a parameter reconfigured by the base station 1050 based on a power preference indicator of the terminal. The RRC related parameter may include a DRX related parameter, and the DRX related parameter may include the content described in S420 and the content described in S720. The terminal message processing unit 1011 may reconfigure (or apply) the RRC related parameters to the terminal.

In addition, the terminal message processing unit 1011 generates a terminal assistance information message. The terminal message processing unit 1011 may generate the terminal assistance information message including at least one of a power preference indicator and a QoS preference indicator. The terminal message processing unit 1011 may generate the terminal assistance information message including at least one of the power preference indicator and the QoS preference indicator based on the power preference state and / or the QoS preference state of the terminal.

The preference determiner 1012 determines the power preference state of the terminal 1000. For example, the preference determiner 1012 may determine one of the normal state and the low power consumption state as the power preference state of the terminal 1000. The meanings of the normal state and the low power consumption state include the content described in S310.

In addition, the preference determiner 1012 determines the QoS preference state of the terminal 1000. The preference determiner 1012 may determine, for example, the QoS preference state according to whether a packet delay budget does not guarantee QoS of a bearer corresponding to a QCI below or below a predetermined level. As another example, the preference determiner 1012 determines the QoS preference state according to whether the 1000 QoS preference state of the UE guarantees QoS of a bearer corresponding to the QCI whose resource type is GBR. can do. As another example, the preference determiner 1012 may determine the QoS preference state according to whether the terminal 1000 guarantees QoS. The meaning and classification of the QoS preference state include the content described in S710.

The terminal transmitter 1020 may transmit the terminal assistance information message generated by the terminal message processor 1011 to the base station 1050.

The base station includes a base station transmitter 1055, a base station receiver 1060, and a base station processor 1070. The base station processor 1070 includes a terminal message processing unit 1011 and a parameter changing unit 1072.

The base station transmitter 1055 may transmit power preference indicator-enabled information, power preference indicator-timer information, and RRC related parameters to the terminal 1000. The power preference indicator-enabled information, power preference indicator-timer information, and RRC related parameters may be transmitted to the terminal 1000 through an RRC connection reconfiguration message.

The base station receiver 1060 receives the terminal assistance information message from the terminal 1000. The terminal assistance information message includes the power preference indicator. The terminal assistance information message may include the QoS preference indicator.

The base station message processing unit 1071 generates an RRC message. For example, the base station message processor 1071 may generate an RRC connection reconfiguration message including the power preference indicator-enabled information and the power preference indicator-timer information. In addition, the base station message processor 1071 may generate an RRC connection reconfiguration message including the RRC related parameters received from the parameter changer 1072. For example, the base station message processing unit 1071 may generate a message having a syntax as shown in Table 2 above.

In addition, the base station message processing unit 1071 analyzes or interprets the syntax of the information or the message received from the base station receiving unit 1060. For example, the base station message processing unit 1071 may analyze or interpret a message having a syntax as shown in Tables 3 to 7.

The base station message processing unit 1071 analyzes or interprets the terminal assistance information message and checks the power preference state of the terminal 1000 indicated by the power preference indicator of the terminal 1000 included in the terminal assistance information message. For example, the power preference state of the terminal 1000 may be a normal state or a low power consumption state.

In addition, the base station message processing unit 1071 analyzes or interprets the terminal assistance information message and checks the QoS preference state of the terminal 1000 indicated by the QoS preference indicator of the terminal 1000 included in the terminal assistance information message. . As an example, the QoS preference state may indicate whether a packet delay budget guarantees QoS of a bearer corresponding to a QCI below a certain level (or below). As another example, the QoS preference state may determine whether to guarantee the QoS of a bearer corresponding to the QCI whose resource type is GBR. As another example, the QoS preference state may indicate whether the QoS guarantee is reserved.

The parameter changing unit 1072 may change or reconfigure RRC related parameters based on the power preference state and / or QoS preference state. The parameter changing unit 1072 may change or reconfigure RRC related parameters by reflecting the power preference state. For example, the parameter changing unit 1072 may reconfigure DRX related parameters, in which case the DRX related parameter reconstruction includes the contents described in S420.

As an example, when the power preference state of the terminal 1000 is the low power consumption state, the parameter change unit 1072 performs RRC related parameter reconfiguration in a direction to reduce battery consumption of the terminal. Specifically, for example, the parameter changing unit 1072 configures or reconfigures the DRX so that the terminal 1000 operates in the long-term DRX mode, or the DRX such that the inactivity time for which the terminal does not monitor the PDCCH subframe is maintained longer. Can be reconstructed.

As another example, when the power preference state is the normal state, the parameter change unit 1072 may perform the RRC related parameter reconstruction in a direction that can increase the transmission efficiency relatively compared to the low power consumption state. Specifically, for example, the parameter changer 1472 may configure the length of the DRX cycle shorter or reconfigure the DRX so that the inactivity time of the terminal 1400 is shorter to increase downlink transmission efficiency. have.

In addition, the parameter changing unit 1072 may change or reconfigure RRC related parameters by reflecting the QoS preference state as well as the power preference state.

For example, when the QoS preference state indicates the guarantee of the QoS of the bearer corresponding to the QCI whose packet delay budget is below (or below) a certain level, the parameter changing unit 1072 may determine that the power preference state of the terminal 1000 is set. Despite the low power consumption state, based on the QoS preference state, RRC-related parameter reconfiguration according to the low power consumption state may not be performed to guarantee QoS. Specifically, for example, if the QoS affinity indicator indicates support or a value of 1,

QCI indexes

1, 2, 3, 5 that do not correspond to QCI indexes 4, 6, 8, and 9 with a packet delay budget of 300 ms or more for the bearer. If the packet delay budget is found to be less than 300ms, the parameter change unit 1072 does not reconfigure the RRC-related parameters based on the low power consumption state in order to guarantee the QoS to the terminal 1000 or the normal state. Based on RRC-related parameter reconstruction can be performed. In addition, when the QoS preference indicator indicates no support or a value of 0, the parameter change unit 1072 may perform RRC related parameter reconstruction based on a low power consumption state regardless of the packet delay budget of the QCI for the bearer.

As another example, when the QoS preference state indicates to guarantee the QoS of the bearer corresponding to the QCI whose resource type is GBR, the parameter changing unit 1072 may guarantee the QoS to perform RRC related parameter reconfiguration or to perform RRC related parameter reconfiguration. May not be performed. Specifically, for example, when the QoS preference indicator indicates support or value 1, when the QCI for the bearer is a GBR type bearer having 1, 2, 3, or 4, the parameter changing unit 1072 may guarantee the QoS for the bearer. In addition, in the case of a non-GBR bearer having a QCI of 5, 6, 7, 8, or 9 for a bearer, RRC related parameter reconfiguration based on a low power consumption state may be performed regardless of QoS. In addition, when the QoS preference indicator indicates no support or a value of 0, the parameter change unit 1072 may perform RRC related parameter reconstruction based on a low power consumption state without guaranteeing QoS for the bearer. That is, even for a GBR bearer, RRC-related parameter reconfiguration may be performed based on a low power consumption state without guaranteeing QoS. Or it may be set to the opposite case by the appointment between the terminal and the base station.

As another example, when the status indicated by the QoS preference indicator indicates whether the QoS guarantee is reserved (or violated), that is, the status indicated by the QoS preference indicator indicates that the base station provides the service to the terminal. In this case, the parameter changing unit 1072 does not perform the RRC related parameter reconstruction based on the low power consumption state by giving priority to the QoS guarantee, or ignores the QoS guarantee and low power consumption. RRC-related parameter reconstruction based on state may be performed. Specifically, for example, if the QoS preference indicator indicates no support or a value of 0, the parameter changing unit 1072 may ignore the QoS for the bearer and perform RRC related parameter reconstruction based on a low power consumption state. . In addition, when the QoS preference indicator indicates support or a value of 1, the parameter changing unit 1072 may perform RRC related parameter reconstruction based on the low power consumption state while guaranteeing QoS for the bearer or at least the RRC related based on the low power consumption state. RRC-related parameter reconstruction may be performed without performing parameter reconstruction.

The parameter changing unit 1072 transmits the changed or reconfigured RRC related parameter to the base station message processing unit 1071. The base station message processing unit 1071 generates an RRC connection reconfiguration message including the reconfigured RRC related parameters. When the DRX related parameter is included in the RRC connection reconfiguration message, the RRC connection reconfiguration message may include a syntax as shown in Table 1 above.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims

A method for supporting power preference of the terminal performed by a terminal,

Receiving, from the base station, a first Radio Resource Control (RRC) Connection Reconfiguration message including power preference indicator-enabled information for allowing a power preference indicator to be transmitted to the base station;

Terminal assistance information message including a power preference indicator (PPI) indicating a power preference state of the terminal and a QoS preference indicator (QPI) indicating a quality of service (QoS) preference state of the terminal Generating and transmitting to the base station; And

Receiving a second RRC connection reconfiguration message from the base station, the second RRC connection reconfiguration message including the RRC related parameters reconfigured by the base station based on the power preference indicator and the QoS preference indicator.
The method of claim 1,

The power preference state of the terminal represents a normal state or a low power consumption state.

The QoS preference state of the UE includes whether a packet delay budget (PDB) guarantees QoS of a bearer corresponding to a QoS Class Identifier (QCI) of less than a certain level, and a resource type of a guaranteed bit rate (GBR). And whether or not to guarantee QoS of the bearer corresponding to the QCI.
The method of claim 2,

The QoS preference indicator of the terminal is included in the terminal assistance information message, when the power preference state of the terminal indicates a low power consumption state, power preference support method.
The method of claim 2,

The terminal assistance information message includes a power preference indicator (PowerPrefIndication) information element (IE),

And the power preference indicator information element indicates a power preference state of the terminal and a QoS preference state of the terminal.
The method of claim 2,

The terminal assistance information message includes a power preference indicator information element and a QoS information indicator (QoSInfoIndication) information element.

And the power preference indicator information element indicates the power preference state of the terminal and the QoS information indicator information element indicates the QoS preference state of the terminal.
A method for supporting power preference of a terminal performed by a base station,

Sending a first RRC connection reconfiguration message to the terminal, the power preference indicator-enabled information allowing the transmission of a power preference indicator to the base station;

Receiving, from the terminal, a terminal assistance information message including the power preference indicator indicating the power preference state of the terminal and a QoS preference indicator indicating the QoS preference state of the terminal;

Reconfiguring RRC related parameters based on the power preference indicator and the QoS preference indicator; And

And transmitting a second RRC connection reconfiguration message including the reconfigured RRC related parameters to the terminal.
The method of claim 6,

The power preference state is characterized in that the normal state or low power consumption state, power preference support method.
The method of claim 7, wherein

The reconfiguring of the RRC related parameter may include reserving the RRC related parameter reconfiguration according to the low power consumption state based on the QoS preference state, even though the power preference state is the low power consumption state. How to support power affinity.
The method of claim 7, wherein

The terminal assistance information message includes a power preference indicator information element,

And the power preference indicator information element indicates a power preference state of the terminal and a QoS preference state of the terminal.
The method of claim 7, wherein

The terminal assistance information message includes a power preference indicator information element and a QoS information indicator information element,

And the power preference indicator information element indicates the power preference state of the terminal and the QoS information indicator information element indicates the QoS preference state of the terminal.
As a terminal that supports power preferences,

A receiving unit for receiving a first RRC connection reconfiguration message from the base station, the power preference indicator-enabled information allowing the transmission of a power preference indicator to a base station;

A preference determination unit for determining a power preference state and a QoS preference state of the terminal;

A message processing unit for generating a terminal assistance information message including the power preference indicator indicating the power preference state and a QoS preference indicator indicating the QoS preference state; And

Including a transmitter for transmitting the generated terminal assistance information message to the base station,

And the receiving unit receives a second RRC connection reconfiguration message from the base station, the second RRC connection reconfiguration message including the RRC related parameters reconfigured by the base station based on the power preference indicator and the QoS preference indicator.
The method of claim 11,

The preference determination unit determines the power preference state of the terminal as a normal state or a low power consumption state,

The preference determination unit determines whether the QoS delay status of the terminal guarantees the QoS of a bearer corresponding to a QCI of less than a certain level, whether the QoS of a bearer corresponding to a QCI whose resource type is GBR, or QoS is determined. The terminal, characterized in that determined according to the guarantee.
The method of claim 12,

In generating the terminal assistance information message, the message processing unit selectively includes the QoS preference information in the terminal assistance information message when the power preference state of the terminal indicates a low power consumption state. Terminal.
The method of claim 12,

The message processing unit generates the terminal assistance information message including a power preference indicator information element,

And the message processing unit indicates the power preference state of the terminal and the QoS preference state of the terminal in the power preference indicator information element.
The method of claim 12,

The message processor generates the terminal assistance information message including a power preference indicator information element and a QoS information indicator information element,

And the message processing unit indicates the power preference state of the terminal in the power preference indicator information element and indicates the QoS preference state of the terminal in the QoS information indicator information element.
As a base station supporting the power preference of the terminal,

A transmitter for transmitting a first RRC connection reconfiguration message including power preference indicator-enabled information to allow transmission of a power preference indicator to the base station;

A receiving unit for receiving a terminal assistance information message including the power preference indicator indicating the power preference state of the terminal and a QoS preference indicator indicating the QoS preference state of the terminal from the terminal;

A parameter changer reconfiguring RRC related parameters based on the power preference indicator and the QoS preference indicator; And

A message processing unit for generating a second RRC connection reconfiguration message including the reconfigured RRC related parameters;

The transmitter, the base station, characterized in that for transmitting the generated second RRC connection reconfiguration message to the terminal.
The method of claim 16,

The parameter changing unit, when the power preference state is a low power consumption state, characterized in that to reconfigure the RRC-related parameters including the DRX-related parameters in a direction of reducing the power consumption of the terminal.
The method of claim 17,

The parameter changing unit, even though the power preference state is the low power consumption state, on the basis of the QoS preference state, characterized in that the RRC-related parameter reconstruction according to the low power consumption state, characterized in that the base station.
According to claim 17,

Although the power preference state is the low power consumption state, the parameter changing unit may perform the low power consumption state only when the packet delay budget of the QCI for the bearer configured in the terminal is less than a certain limit based on the QoS preference state. And perform the RRC related parameter reconfiguration according to the present invention.
The method of claim 17,

Although the power preference state is the low power consumption state, the parameter changing unit may determine whether the resource type of the QCI for the bearer configured in the UE is GBR based on the QoS preference state. And perform the RRC related parameter reconfiguration according to the present invention.