WO2010060261A1

WO2010060261A1 - Controlling method for mobile communication terminal receiving downlink data and mobile communication terminal

Info

Publication number: WO2010060261A1
Application number: PCT/CN2009/001170
Authority: WO
Inventors: 谢芳; 胡臻平; 崔春风
Original assignee: 中国移动通信集团公司
Priority date: 2008-11-03
Filing date: 2009-10-22
Publication date: 2010-06-03
Also published as: CN101730206A

Abstract

A mobile communication technology, specially a receiving downlink data technology for discontinuous reception of a mobile terminal is provided, and a downlink data receiving controlling method and a mobile communication terminal to reduce the electricity consume of the mobile communication terminal are provided. Only after the downlink data is received and judged not to be received correctly, the controlling method for receiving the downlink data and the mobile communication terminal start the timer for detecting the receiving time of the retransmission data, the start of the timer is avoided when the data is received correctly, then the number of times of starting the timer is reduced largely, and the extra electricity consume is avoided. Furthermore, because the starting time of the timer is the time of sending NACK, so the set time length of the timer could be reduced, then the running time of the timer is reduced further, and the electricity consume of eUE is reduced further too.

Description

Control method for mobile communication terminal receiving downlink data and mobile communication terminal

The present invention relates to mobile communication technologies, and in particular, to a technique for a mobile terminal that receives discontinuous reception to receive downlink data. Background technique

The Discontinuous Reception (DRX) function allows the user equipment (User Equipment: UE) to shut down the receiver under certain conditions without constantly listening to the Physical Downlink Control Channel (PDCCH). The purpose of the electricity.

The basic principle of DRX is shown in Figure 1. The DRX period consists of the continuous PDCCH listening phase (On Duration) and the possible sleep phase (Opportunity for DRX). The units of the On Duration phase and the Opportunity for DRX phase are all subframes. number. In the On Duration phase, the UE must continuously listen to the PDCCH to obtain the resource allocation indication of the uplink and downlink transmission of each subframe, and determine the uplink and downlink allocated by the base station to the base station according to the obtained resource allocation indication of the uplink and downlink transmission of each subframe. Time-frequency resources, and data processing on the allocated time-frequency resources. The UE may not need to continuously listen to the PDCCH during the Opportunity for DRX phase.

In the E-UTRAN (Evolved Universal Terrestrial Radio Access Network) system, in order to save the battery consumption of the UE when there is no data to be transmitted and received, the UE can perform a DRX operation, that is, temporarily turn off the receiver. Awakening at the time agreed with the base station to listen to the corresponding PDCCH, so as to know whether the base station needs to send data to the UE during the sleep phase. The DRX operation includes some set parameters and some control timers. For example, the included parameters include a DRX cycle, and the included timers include an On Duration Timer and a DR inactivity timer. DRX Inactivity Timer) and so on. The UE listens to the PDCCH during the On Duration phase. If the data indication sent by the base station to the base station is not detected, the UE enters the dormant phase after the On Duration Timer expires; if the UE listens during the On Duration phase The PDCCH learns that there is a data indication sent to itself, and then starts the DRX Inactivity Timer. If the PDCCH again indicates that data is transmitted to the UE before the DRX Inactivity Timer expires, the DRX Inactivity Timer is restarted; only when the DRX Inactivity Timer and the On Duration are When the Timer expires, the UE can enter the sleep phase. Therefore, the UE remains in the Active state during the On Duration phase of the DRX cycle, and may be active or may be in the Sleep state during the Opportunity for DRX phase.

In the E-UTRAN system, the DR control and the hybrid automatic repeat request (HARQ) are respectively operated independently, that is, the evolved user equipment (eUE) in the LTE system is required when downlink data retransmission is required in the HARQ. Regardless of the state of the current DR operation, the receiver must be started to listen to the PDCCH according to the set HARQ RTT (Round Trip Time) Timer in preparation for receiving the downlink retransmission data. In addition, HARQ does not further affect normal DRX operation. And because the LTE downlink adopts asynchronous HARQ, the existing LTE Release 8 (Release 8, R8) also defines a DRX Retransmission Timer related to the downlink HARQ data transmission control, so that the eUE is in a certain time. When the retransmitted data is not received, the receiver can be turned off and restored to the sleep state.

The following is an example of determining, by using the resource allocation indication of the PDCCH, that the evolved base station (eNB) in the LTE system allocates downlink data transmission resources for the eUE in the subframe, as described in the following example. The eUE performs the cooperation control process between the DR and the downlink HARQ in the LTE R8.

As shown in Figure 2, taking a DR cycle as an example, the DRX cycle is 20 subframes, where: the On Duration phase is two subframes, and the DRX Inactivity Timer is two subframes. The existing standard specifies one subframe. The length is lms. If the eUE detects the downlink data sent to itself in the first subframe of the On Duration phase, the receiving control process of the downlink data specifically includes the following steps:

S201: The eUE starts a first timer, that is, a HARQ RTT Timer, in the first subframe of the current DRX cycle, and processes the downlink data; and the eUE starts the DRX Inactivity Timer; 5202, the eUE determines whether the downlink data is correctly received. If the eNB receives the ACK (Acknowledgement), if the downlink data is not received correctly, the eUE feeds back the NACK (Negative Acknowledgement) to the eNB;

The purpose of the HARQ RTT Timer is to determine the minimum time interval before the possible retransmission data arrives. The timing of the HARQ RTT Timer can only be less than or equal to the minimum time interval to ensure that the eUE receives the retransmission data when the receiver is in the receiving state. In the prior art, the eUE receives and processes the downlink data, which generally takes 4 ms, that is, the 4th subframe after the first subframe of the current DR period may feed back ACK or NACK to the eNB, and the ACK or NACK arrives at the eNB for transmission delay and the eNB. The sum of time for demodulating ACK or NACK is generally 4ms. Thus, even if the eNB demodulates the NACK and immediately schedules retransmission of data, the retransmitted data will be sent to the eUE in the 8th subframe after the first subframe. Therefore, when setting the timing duration of the HARQ RTT Timer, the minimum time interval is generally set to 8 ms, thereby ensuring that the receiver is turned on before the retransmission data arrives to ensure that the retransmission data can be received.

5203. When the timing of the HARQ RTT timer arrives and the downlink data is not correctly received, that is, when the eUE feeds back the NACK to the eNB, the eUE turns on the receiver, ends the sleep state, enters the receiving state, and starts another timer DRX Retransmission Timer.

The DRX Retransmission Timer is started to monitor the waiting time for receiving retransmission data. When the eNB prevents the eNB from demodulating the NACK into an ACK and then does not retransmit the data, the eUE waits indefinitely. The timing length is determined according to the required maximum waiting duration. The eNB is configured to the eUE through an adio Resource Control (RRC) procedure. During the operation of the DRX Retransmission Timer, if the eUE correctly receives the retransmitted data, the receiver turns off the receiver and enters the sleep state after receiving the data. When the DRX Retransmission Timer is set to receive no retransmission data, the eUE does not. Wait again, turn off the receiver, and go to sleep.

If the eUE does not detect the downlink data indication sent to itself on the PDCCH during the On Duration phase, the eUE turns off the receiver and enters the dormant phase after the On Duration phase ends; if the eUE listens to the PDCCH in the On Duration phase, the PDCCH is informed that there is a transmission. When the data is indicated to itself, the DRX Inactivity Timer is started. If the PDCCH again indicates that data is transmitted to the eUE before the DRX Inactivity Timer expires, the DRX Inactivity Timer is restarted; only when DRX When the Inactivity Timer and the On Duration Timer both expire, the eUE can enter the sleep phase. When the eUE fails to correctly receive downlink data, the eUE also needs to open the receiver after the HARQ RTT Timer expires, and the maximum time that is turned on is equal to the duration of the DRX Retransmission Timer.

However, the inventors have found that, in the current cooperation mechanism between DRX and downlink HARQ, the PDCCH refers to

Timer, in fact, when the eUE correctly receives the downlink data and feeds back the ACK to the eNB, it does not cause retransmission of the downlink data. Therefore, the eUE does not make any sense to start the HARQ RTT Timer in this case, but causes unnecessary power. waste. Summary of the invention

Embodiments of the present invention provide a downlink data receiving control method and a mobile communication terminal, which are used to reduce power consumption of a mobile communication terminal.

A method for controlling downlink data reception by a mobile communication terminal according to an embodiment of the present invention includes: receiving downlink data and determining that downlink data is not correctly received, returning incorrect reception indication information to a base station, and starting to control receiving the downlink a timer for restarting data retransmission data;

When the timing of the timer arrives, if the mobile communication terminal is in the sleep state, the receiver is turned on to wait for reception of the retransmission data.

The timing duration of the timer is determined according to a minimum time interval between the start time of the start timer and the retransmission data arrival time of the downlink data. Preferably, the start time according to the start timer is The minimum time interval between the arrival times of the retransmission data of the downlink data determines the timing duration of the timer, including: the timing duration is less than or equal to the minimum time interval.

The minimum time interval is: the transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station when the start time of the start timer is the same as the time of the incorrect reception indication information. And adding a sum obtained after the base station processes the time required to correctly receive the indication information;

When the start time of the start timer is earlier than the time when the indication information is not correctly received, The minimum time interval is: the transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station, plus the time required by the base station to process the incorrectly received indication information, the timer start time, and the incorrect Receiving the sum obtained after the time difference between the transmission times of the indication information;

When the start time of the start timer is later than the time when the indication information is not correctly received, the minimum time interval is: a transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station, plus The value obtained by the upper base station processing the sum obtained by the time required to correctly receive the indication information, and subtracting the time difference between the timer start time and the time when the indication information transmission time is not correctly received.

Preferably, the transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station, plus the time required by the base station to process the incorrect reception of the indication information, is: 4 milliseconds.

A mobile communication terminal, including a transmitter, further comprising:

a timer, configured to control a startup time of receiving retransmission data;

a receiver, configured to receive downlink data, and determine that the downlink information is not correctly received, and output the first indication information;

a control unit, configured to return, according to the first indication information output by the receiver, the incorrect reception indication information to the base station by using the transmitter, and start the timer, and if the timing duration of the timer arrives, if When the mobile communication terminal is in the dormant state, the receiver is turned on to wait for receiving the retransmission data of the downlink data.

The downlink data receiving control method and the mobile communication terminal provided by the embodiments of the present invention start a timer for monitoring a minimum time interval before the arrival of the possible retransmission data, after receiving the downlink data and determining that the data is not correctly received, to avoid The timer is started when the data has been correctly received, thereby greatly reducing the number of timer starts and avoiding additional power consumption. Further, since the start time of the timer is the time for transmitting the NACK, the set duration of the timer can be reduced, thereby further reducing the running time of the timer, thereby further reducing the power loss of the eUE. DRAWINGS 1 is a schematic diagram of a DRX control mechanism of a mobile communication terminal in the prior art; FIG. 2 is a schematic diagram of a downlink data reception control principle of a mobile communication terminal in the prior art; FIG. 3 is a schematic diagram of a downlink data reception control principle of a mobile communication terminal according to an embodiment of the present invention; FIG. 4 is a schematic structural diagram of a mobile communication terminal according to an embodiment of the present invention. detailed description

In order to reduce the power loss of the eUE, the embodiment of the present invention provides the following technical solution: The eUE starts the timer for controlling the retransmission data reception only after the NACK is fed back to the eNB, thereby avoiding the timer start after receiving the downlink data correctly, thereby saving The power consumption of the eUE.

As shown in Figure 3, the DRX cycle is set to 20 subframes. The On Duration phase is two subframes. If the eUE detects the downlink data in the first subframe of the On Duration phase, the receiving control process of the downlink data specifically includes the following steps:

The S30K eUE receives the downlink data, and determines whether the downlink data is correctly received. If the data is correctly received, the eUE feeds back the ACK to the eNB; if the downlink data is not received correctly, the eUE feeds back the NACK to the eNB;

It should be noted that, after determining that the downlink data is correctly received, the eUE may not feed back any information to the eNB, and only feed back the NACK to the eNB when the eNB does not receive the correct information, so that the default data has been correctly received when the eNB does not receive any feedback information of the eUE. And retransmit the data when the NACK is received.

S302, the eUE starts a timer for the corresponding HARQ process when the NACK is fed back to the eNB, and is used by the eNB to process an eNB Processing Timer according to an embodiment of the present invention;

The role of the eNB processing delay timer is still to monitor the minimum time interval before the retransmission data arrives. The eNB processing delay timer must be less than or equal to the minimum time interval to ensure that the receiver is turned on before the retransmission data arrives. When the eNB processes the timing duration of the delay timer, if the eUE is in the dormant state, the eUE needs to turn on the receiver to end the sleep state, and wait to receive the retransmission data.

The eUE starts the timer at the same time as the NACK, for example, the same subframe or the same millisecond (ms), or different, as long as the timer is less than or equal to the timer: The start time and the time interval between the earliest possible arrival time of the retransmission data of the downlink data. The time interval between the earliest possible arrival time of the retransmission data and the start time of the timer is the minimum time interval before the retransmission data arrives. The timer must expire before the retransmission data arrives or just arrives, thereby triggering the eUE to open the reception. machine.

When the start time of the timer and the transmission time of the NACK are the same, the minimum time interval is exactly: the transmission delay of the incorrect reception indication information NACK between the mobile communication terminal and the base station, plus the time required for the base station to process the NACK After the sum obtained. When the start time of the timer is earlier than the transmission time of the NACK, the minimum time interval should be correspondingly added to the time difference between the timer start time and the NACK transmission time. Otherwise, when the timer start time is later than the NACK transmission time, The minimum time interval should be the value obtained by subtracting the time difference between the timer start time and the NACK transmission time.

The following is a detailed description of the preferred embodiment with the same timer start time and NACK transmission time.

S303. When the eNB processes the delay time of the delay timer, if the eUE is in the dormant state, the eUE turns on the receiver to end the sleep state, enters the receiving state of the retransmission data, and starts another timer DRX Retransmission Timer.

If the eUE receives the retransmitted data during the DRX Retransmission Timer, the receiver is turned off and then enters the sleep state after receiving the retransmitted data; if the eUE does not receive the retransmitted data during the DRX Retransmission Timer, the DRX Retransmission Timer When the set time is reached, the receiver is turned off and goes to sleep again. Of course, if the DRX Inactivity Timer has not expired when the DRX Retransmission Timer expires, the eUE needs to shut down the receiver and enter the sleep state again when the DRX Inactivity Timer expires.

In this way, after the eUE receives the downlink data and determines that the data is correctly received, since the later data retransmission does not occur, the eNB does not start the delay timer, thereby reducing the number of timer starts and avoiding additional power. Consumption. Especially in an environment with good communication conditions, the probability of data retransmission is very low, and the power consumption of the eUE is greatly saved.

Referring further to FIG. 2, when the prior art sets the timing duration of the first timer, it needs to be tested. Considering the minimum time interval before the possible retransmission data arrives, the minimum time interval includes the sum of the following three parts: eUE receives the time required to process the downlink data, the transmission delay of the ACK or NACK sent by the eUE to the eNB, and the eNB solution The time required to process and process the ACK or NACK, and the maximum duration of the first timer can only be the minimum time interval. Otherwise, it is possible to miss the retransmission data when the receiver is turned on. In the prior art, the minimum time interval is generally 8 ms, so the maximum duration of the first timer is set to 8 ms. As shown in FIG. 3, after the technical solution provided by the embodiment of the present invention is used, the start time of the eNB processing the delay timer is the time for sending the NACK. Therefore, when the eNB processes the maximum duration of the delay timer, only the eUE needs to be considered. The transmission delay of the NACK sent to the eNB and the time required for the eNB to demodulate the NACK. Generally, the sum of the two parts of time is substantially equal to the time required for the eUE to receive the processed downlink data, so the transmission delay of the ACK or NACK and the eNB The sum of the time required to demodulate the ACK or the NACK is set to be 4 ms when the eNB processes the delay timer, for example, 4 ms, thereby further reducing the running time of the timer, thereby further saving the power loss of the eUE. Of course, the maximum duration of the eNB processing delay timer may also be set to 3 ms or 2 ms.

The above analysis of the prior art is based on the fact that the eUE can obtain the uplink resource that sends the NACK feedback information to the eNB after determining that the downlink data is not correctly received, so that the NACK feedback information is successfully sent, according to the duplex mode of the FDD system, in the FDD. There is no problem in the system, but in the TDD system, there are 7 different uplink and downlink time slot ratios. After the eUE determines that the downlink number is not correctly received, there may be no uplink resources available immediately for feedback NACK. This causes the length of the DRX Retransmission Timer to be set long enough to ensure that the eNB schedules retransmission of eUE during the DRX Retransmission Timer. Therefore, in the prior art, for the TDD system, it must be considered that the eUE may not receive the retransmitted data in the thousands of hours after the receiver is turned on, which causes unnecessary power consumption. At the same time, this also means that the eNB must schedule the downlink retransmission data sent to the eUE within the remaining time of the DRX Retransmission Timer, which will reduce the flexibility of the eNB scheduling and cause the eUE to not use the smaller DRX Retransmission Timer duration. Such as lms, 2ms, etc., and must use larger values such as 16ms, 24ms, 33ms, etc., which further reduces the power saving function of the DRX mechanism. After the technical solution provided by the embodiment of the present invention is used, in the TDD system, the start time of the eNB processing delay timer is The time when the NACK is sent. Therefore, when the eNB processes the maximum duration of the delay timer, it does not need to consider the downlink transmission and the corresponding uplink ACK or NACK feedback information caused by the difference between the TDD uplink and downlink slot ratio and the used downlink subframe. The difference between the delays only needs to consider the transmission delay of the NACK sent by the eUE to the eNB and the time required for the eNB to demodulate the NACK, thereby further reducing the running time of the timer in the TDD system and improving the scheduling retransmission of the eNB. The flexibility of the data.

In the embodiment of the present invention, the technical solution is described in detail by taking the receiving control of one downlink data as an example. In fact, the receiving control process of each downlink data is completely the same.

As shown in FIG. 4, an embodiment of the present invention further provides a mobile communication terminal, including a transmitter 403, and further includes:

a timer 401, configured to control a start time of receiving retransmission data, where a timing of the timer 401 is determined according to a minimum time interval between a start time of the start timer 401 and a retransmission data arrival time of the downlink data;

The receiver 402 is configured to receive downlink data, and determine that the downlink information is not correctly received, and output the first indication information;

The control unit 404 is configured to: according to the first indication information output by the receiver 402, return the incorrect reception indication information to the base station by the transmitter 403 and start the timer 401, and when the timing duration of the timer 401 arrives, if the mobile communication terminal arrives When in the sleep state, the receiver 402 is turned on to wait for receiving retransmission data of the downlink data.

Further, the receiver 402 is further configured to output the second indication information when the downlink data is correctly received. The control unit 404 is further configured to return the correct reception indication information to the base station by using the transmitter 403 according to the second indication information output by the receiver.

According to the foregoing, the timer duration of the timer 401 is less than or equal to the minimum time interval before the retransmission data arrives.

When the start time of the start timer is the same as the start time of the incorrect reception indication information, the minimum time interval is: the transmission delay of the indication information transmitted between the mobile communication terminal and the base station is not correctly received, and the base station is added. The sum obtained after processing the time required to receive the indication information correctly.

Preferably, the transmission of the indication information between the mobile communication terminal and the base station is not correctly received. The delay, plus the time taken by the base station to process the time when the indication information is not correctly received, is: 4 milliseconds. In summary, the downlink data receiving control method and the mobile communication terminal provided by the embodiments of the present invention start a timer for monitoring the retransmission data receiving time only after receiving the downlink data and determining that the number is not correctly received. The timer is started when the data has been correctly received, thereby greatly reducing the number of timer starts and avoiding additional power consumption. Further, since the start time of the timer is the time for transmitting the NACK, the set duration of the timer can be reduced, thereby further reducing the running time of the timer, thereby further reducing the power loss of the eUE. In the TDD system, the eUE is prevented from opening the receiver in advance to wait for receiving retransmission data, and the flexibility of the eNB to schedule retransmission data is improved.

It is apparent that those skilled in the art can make various modifications and variations to the embodiments of the invention without departing from the spirit and scope of the invention. Therefore, it is intended that the present invention cover the modifications and modifications of the invention as claimed.

Claims

Rights request

A control method for receiving downlink data by a mobile communication terminal, comprising: receiving downlink data and determining that a downlink number is not correctly received, returning an incorrect reception indication information to a base station, and starting to control reception a timer for starting the retransmission data of the downlink data;

The control method according to claim 1, wherein the timing duration of the timer is determined according to a minimum time interval between a start time of the start timer and a retransmission data arrival time of the downlink data.

The control method according to claim 2, wherein the determining the timing duration of the timer according to the minimum time interval between the start time of the start timer and the retransmission data arrival time of the downlink data includes: The timing duration is less than or equal to the minimum time interval.

The control method according to claim 3, wherein when the start time of the start timer and the send time of the incorrect reception indication information are the same, the minimum time interval is: the incorrect reception indication information a transmission delay transmitted between the mobile communication terminal and the base station, plus a sum obtained after the base station processes the time required for the water to correctly receive the indication information;

When the start time of the start timer is earlier than the time when the indication information is not correctly received, the minimum time interval is: a transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station, plus a sum obtained by the upper base station after processing the time difference between the time required to correctly receive the indication information, the timer start time, and the time when the indication information is not correctly received;

The control method according to claim 4, wherein the transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station is added, and the base station needs to process the incorrect reception of the indication information. The sum obtained after time is: 4 ms.

A mobile communication terminal, comprising a transmitter, further comprising:

a timer, used to control the start time of receiving retransmissions;

The mobile communication terminal according to claim 6, wherein the timing duration of the timer is determined according to a minimum time interval between a start time of the start timer and a retransmission data arrival time of the downlink data. .

The mobile communication terminal according to claim 7, wherein the timer has a timing of less than or equal to the minimum time interval.

The mobile communication terminal according to claim 8, wherein when the start time of the start timer and the send time of the incorrect reception indication information are the same, the minimum time interval is: the incorrect reception And indicating a transmission delay between the mobile communication terminal and the base station, and a sum obtained after the base station processes the time required to correctly receive the indication information;

When the start time of the start timer is later than the time when the indication information is not correctly received, the minimum time interval is: a transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station, plus a sum obtained by the upper base station processing the time required to correctly receive the indication information, The value obtained after subtracting the time difference between the timer start time and the time when the instruction information is not correctly received is subtracted.

The mobile communication terminal according to claim 9, wherein the transmission delay of the incorrectly received indication information transmitted between the mobile communication terminal and the base station is added, and the base station processes the incorrectly received indication information. The sum obtained after the time is required: 4 ms.