TW201603622A - Drx coordination mechanism in dual connectivity system - Google Patents

Abstract

The invention provides a mechanism of coordinating DRX information in a dual connectivity system. A method of coordinating DRX information of a UE in a master e NB of a dual connectivity system includes: A. receiving first information characterizing a DRX state of the UE for a secondary e NB or transmitting second information, determined by the master e NB, indicating a DRX state of the UE for the master e NB to the secondary e NB; and B. the master e NB exchanging DRX configuration information for the UE with the secondary e NB. With the mechanism of coordinating DRX information according to the invention, dynamic power management of the UE can be enabled to thereby save power consumption of the UE and also improve the transmission efficiency of information.

Description

DRX coordination mechanism in dual connectivity systems

The present invention relates generally to the field of wireless communications, and more particularly to DRX coordination mechanisms for use in dual connectivity systems.

The DRX can be used to save the power of the UE in the RRC connected state. The DRX configuration is a compromise between power consumption and Quality of Service (QoS). In a dual connectivity system, the UE is connected to a primary base station (MeNB) and a secondary base station (SeNB), respectively, and may transmit different services through different base stations. Therefore, there is a need to define a DRX mechanism in a dual connectivity system.

In the current DRX mechanism, the DRX function can be configured and controlled for the UE in the Radio Resource Control (RRC) connection state, so that the UE does not need to always detect the downlink channel, that is, the PDCCH. The DRX cycle consists of two parts, (1) "On Duration" during which the UE monitors the PDCCH; (2) "DRX Period" during which the user can skip the monitoring of the downstream channel to save power. . The RRC controls the operation of the DRX by configuring multiple parameters, such as the length of the short DRX cycle, the length of the long DRX cycle, or the timing. number. The transition between the short DRX cycle, the long DRX cycle, and the continuous reception is controlled by a timer or by a determination command by the base station. During the "working period" of the long DRX cycle and the short DRX cycle, the UE detects the PDCCH. If the scheduling command of the base station is received at this time, the UE starts the "inactivity timer" and during the "inactive timer" operation Each subframe monitors the PDCCH. In the meantime, the UE can be considered to be in continuous reception mode. When the "inactivity timer" is running, the UE will re-time the timer once it receives the scheduling information on the PDCCH. When the timer expires, the UE enters the short DRX cycle and starts the "short DRX cycle timer". When the timer expires, the UE enters a long DRX cycle and accordingly begins a long DRX cycle count. The short DRX cycle is also initiated by the MAC Control element.

Based on the above process, most of the startup time is controlled by the scheduling instructions. Since the connection between the MeNB and the SeNB is a non-ideal backhaul, the MeNB and the SeNB support distributed scheduling, and the MeNB and the SeNB do not know each other about the scheduling situation, so it is difficult to predict the transmission of the scheduling command and how each timer works, thereby making it difficult to make two The base station's DRX is aligned, which in turn saves UE power consumption.

In a dual connectivity system, power management of the uplink is an urgent problem to be solved. For users supporting dual connectivity, simultaneous uplink transmission to the MeNB and the SeNB is supported. That is, the user's uplink power will be shared between the two base stations. It is currently discussed in 3GPP RAN1 whether to support users to dynamically share uplink transmit power between two base stations and how to support them. Since the MeNB and the SeNB support distributed scheduling, if the delay of the non-ideal backhaul between the MeNB and the SeNB is high, it is impossible to perform the exchange. Scheduling information, it is difficult to know the scheduling status of each other between the two base stations, and thus it is impossible to coordinate each other's power usage so that the total transmission power of the user does not exceed the maximum allowable power. If the interaction between the MeNB and the SeNB corresponds to the information of one base station (MeNB or/and SeNB) entering the DRX period, then one base station will know that the user will not perform uplink transmission on another base station, so The maximum power of the UE can be used for uplink transmission to a base station, so that the dynamic power sharing mechanism can be better supported to improve the efficiency of the system.

However, how to coordinate the DRX configuration between the MeNB and the SeNB and the interactive DRX related information are still in the blank.

In view of the above problems, the present invention provides a DRX coordination mechanism by which a base station can perform effective dynamic power on a UE.

A first aspect of the present invention provides a method for coordinating DRX information of a user equipment in a base station of a dual connectivity system, including: A: a primary base station and a secondary base station acquire DRX status information of the user equipment; The primary base station and the secondary base station exchange DRX configuration information for the user equipment.

Preferably, the step A further includes: when one of the primary base station and the secondary base station determines that the user equipment enters the DRX state corresponding to the base station, the base station Sending the DRX status information of the user equipment to another base station in the primary base station and the secondary base station; the user equipment will correspond to the primary base station and The DRX status information of one of the base stations in the secondary base station is transmitted to the other base station.

Preferably, one of the primary base station and the secondary base station is capable of being based on the DRX status of the user equipment corresponding to another base station and/or the DRX configuration information of the user equipment corresponding to another base station. Determining a time at which the user equipment corresponds to the other base station entering discontinuous reception and/or ending a discontinuous reception into a continuous reception.

Preferably, the DRX state is that the user equipment enters a discontinuous reception state corresponding to the another base station and/or ends a discontinuous reception state and/or enters a continuous reception state.

Preferably, the primary base station sends its DRX configuration information to the secondary base station through an add secondary base station message sent to the secondary base station, and/or the primary base station receives the secondary base The secondary base station cell modification information of the station receives the DRX configuration information or the DRX reconfiguration information of the secondary base station; and/or when one of the primary base station or the secondary base station reconfigures its DRX configuration And one of the primary base station or the secondary base station transmits its reconfigured DRX configuration information and/or the user equipment DRX status information to another base station in the primary base station or the secondary base station.

A method for coordinating DRX information of a user equipment in a primary base station of a dual connectivity system according to the second aspect of the present invention includes: A: receiving first information indicating that the user equipment is in a DRX state of the secondary base station Or sending the determined second information indicating the DRX status of the user equipment for the primary base station to the secondary base station; B: The primary base station interacts with the secondary base station for DRX configuration information of the user equipment.

Preferably, the primary base station receives the first information from the user equipment or the secondary base station; or the primary base station receives the first information sent by the secondary base station together The DRX configuration information reconfigured with the secondary base station.

Preferably, when the primary base station reconfigures its DRX configuration, the primary base station transmits its reconfigured DRX configuration information to the secondary base station; or the primary base station reconfigures it The DRX configuration information is sent to the secondary base station along with the second information.

A third aspect of the present invention provides a method for coordinating DRX information of a user equipment in a secondary base station of a dual connectivity system, comprising: A: receiving a DRX for indicating that the user equipment enters a primary base station Third information of the status, or sending the determined fourth information for indicating the DRX status of the user equipment for the secondary base station to the primary base station; B: the secondary base station and the primary base station Interacting DRX configuration information for the user device.

Preferably, the secondary base station receives the third information from the user equipment or the primary base station; or the secondary base station receives the primary base station sent by the primary base station together The reconfigured DRX configuration information and the third information.

Preferably, the step B further includes: the secondary base station receiving the DRX configuration information of the primary base station by receiving information from the secondary base station of the secondary base station of the primary base station; and/ Auxiliary base station Sending, by the primary base station, the secondary base station cell modification information of the secondary base station to transmit DRX configuration information of the secondary base station or DRX configuration information of the secondary base station reconfiguration.

Preferably, when the secondary base station reconfigures its DRX configuration, the secondary base station sends its reconfigured DRX configuration information to the primary base station along with the fourth information.

Preferably, the step B further includes: the secondary base station receiving the DRX configuration information reconfigured by the primary base station.

A fourth aspect of the present invention provides a method for coordinating DRX information in a user equipment of a dual connectivity system, including: when the user equipment enters a DRX state corresponding to a first base station, the use The device sends a first information indicating that the user equipment enters the DRX state to the second base station.

Through the configuration method of the discovery resource and the discovery cycle proposed by the present invention, the communication system can avoid resource conflicts, improve resource utilization, and ensure communication reliability.

The invention will be better understood, and the other objects, details, features and advantages of the invention will become more apparent from the Detailed Description. In the drawings: FIG. 1 is a flow chart of DRX status notification in a dual connectivity system in accordance with an embodiment of the present invention.

Preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While the preferred embodiment of the present invention has been shown in the drawings, it is understood that Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Embodiments of the invention are set forth in conjunction with the drawings.

1 is a flow chart of DRX status notification in a dual connectivity system in accordance with an embodiment of the present invention.

In the DRX mechanism, the DRX control function is performed by the UE based on the configuration of the current eNB. Since the eNB can acquire the DRX parameter configuration of the UE and scheduling information such as the PDCCH, the eNB can also obtain an operation related to the DRX state of the UE by using the above parameters and information.

When the UE enters the DRX period corresponding to the MeNB, the time point of the UE entering the startup state corresponding to the MeNB can also be determined, and the length of the DRX period is controlled by corresponding parameters corresponding to the DRX state. Obviously, when the UE enters the DRX period, the MeNB connected thereto can determine that the UE enters the DRX period, and correspondingly, in conjunction with the DRX configuration parameter, the MeNB can also know the time when the UE enters the startup state.

It can be seen from the background that during the DRX period, the UE will not receive the downlink scheduling information from the MeNB and will not perform the uplink transmission. Therefore, during the time period, the UE can fully utilize the power of the UE for the uplink transmission of the SeNB, thereby implementing dynamic Power management. Obviously, before this, the SeNB needs It is necessary to know the related information of the DRX period corresponding to the MeNB. For the information about how the SeNB obtains the DRX period in which the UE enters the MeNB, the present embodiment proposes two notification schemes:

Scheme A: The SeNB is notified by the MeNB.

In this solution, for the DRX state of the UE corresponding to the MeNB, the MeNB can determine the DRX state of the UE side according to the DRX configuration information and the scheduling information. The MeNB can transmit information indicating the DRX state of the UE to the SeNB, thereby enabling the SeNB to acquire the current DRX state of the UE corresponding to the MeNB.

Scheme B: The SeNB is directly notified by the UE.

In this scheme, the UE directly transmits information indicating the DRX state corresponding to the MeNB to the SeNB. Thereby, the SeNB can acquire the current DRX state of the UE corresponding to the MeNB.

It can be understood that, because there is a certain delay in the transmission between the MeNB and the SeNB, in the scheme A, the time point at which the SeNB receives the first information is not a certain value. Different from the scheme A, since the transmission delay between the UE and the SeNB can be estimated, the time point at which the SeNB receives the DRX state information corresponding to the UE and the MeNB can be estimated.

After the SeNB learns the current DRX status information corresponding to the MeNB, the SeNB can directly determine that the UE enters the discontinuous reception state (ie, the DRX period) and/or ends the discontinuous reception state (ie, the DRX period) into the continuous reception state ( Startup state). Or, in combination with the DRX configuration information of the MeNB to the UE, it can be determined that the UE enters the non-connected mode for the MeNB. The time at which the reception is continued (ie, the DRX period) and/or the end of the discontinuous reception (ie, the DRX period) enters the moment of continuous reception (starting state).

In this embodiment, the MeNB transmits the DRX configuration information of the UE corresponding to the MeNB to the SeNB through the SCG Addition/Modification Indication of the SeNB transmitted to the SeNB.

If the type of the service is changed for some reasons, the MeNB needs to reconfigure the DRX information for the UE. Therefore, the MeNB needs to send the reconfigured DRX configuration information to the SeNB.

Optionally, the MeNB may send the reconfigured DRX configuration information to the SeNB along with the DRX status information corresponding to the MeNB.

After the SeNB acquires the DRX configuration information of the MeNB from the MeNB, the DRX status information corresponding to the MeNB obtained in combination with the obtained MeNB can more accurately know the time (ie, the DRX period) and/or the end of the UE for the MeNB to enter the discontinuous reception. The discontinuous reception (ie, the DRX period) enters the moment of continuous reception (starting state).

Similarly, the SeNB needs to send the DRX status information corresponding to the SeNB of the UE and the DRX configuration information corresponding to the SeNB to the MeNB or the UE to send the DRX status information corresponding to the SeNB to the MeNB. In order to enable the MeNB to learn information about the UE entering the DRX state corresponding to the SeNB, and in combination with the obtained configuration information of the DRX corresponding to the SeNB, it can be more accurately known that the UE enters the discontinuous reception (ie, the DRX period) and/or for the SeNB. Ending the discontinuous reception (ie, the DRX period) enters the moment of continuous reception (starting state).

In this embodiment, the SeNB sends the UE by using the secondary cell group modification message. The DRX configuration information corresponding to the SeNB is sent to the MeNB.

Similarly, if the SeNB reconfigures the current DRX configuration information, the SeNB needs to send the modified DRX configuration information to the MeNB. In this embodiment, the SeNB may also send the reconfigured DRX configuration information to the MeNB by using the foregoing SCG modification information.

It can be seen from the above that the SeNB can further determine that the UE enters the time (initial state) corresponding to the discontinuity of the MeNB (ie, the DRX period) and/or the end of the discontinuous reception (ie, the DRX time) into the continuous reception (the startup state). Consider the delay introduced due to the non-ideal backhaul between the MeNB and the SeNB. That is, since there is a certain delay in the transmission between the MeNB and the SeNB, the time point at which the SeNB receives the first information is not a certain value, but it can be roughly estimated that the UE enters the discontinuous reception (ie, the DRX period) and / or end the discontinuous reception (ie DRX time) into the moment of continuous reception (starting state).

Therefore, through the above process, the MeNB/SeNB can know that the UE enters a discontinuous reception state (for example, a DRX period) and/or ends a discontinuous reception state (for example, a DRX period) corresponding to another base station (SeNB/MeNB). Continuously receiving the state (initiating state), thereby implementing dynamic power management. For example, when the UE is in the DRX period of the MeNB, the uplink transmission of the UE corresponding to the SeNB may use the entire power of the UE to transmit data.

The following is exemplarily illustrated for a plurality of non-limiting DRX state information of the UE, and those skilled in the art can understand that the DRX state of the UE may also include other states.

State 1: The UE starts to use the long DRX cycle; specifically, if the UE configures the short DRX cycle, when the DRX short cycle timer (drx-ShortCycleTimer) count expires; or if the UE does not configure the short DRX cycle, only the long DRX cycle is configured. The DRX inactivity timer expires or receives the DRX Command MAC control element.

State 2: The UE uses a long DRX cycle, and the working period timer (OnDurationTimer) expires, and the DRX-InactivityTimer does not run; since the OnDurationTimer specifies the number of subframes of the PDCCH to be monitored from the subframe of the DRX cycle, Therefore, this scenario corresponds to the UE not successfully decoding the PDCCH during operation.

Therefore, this state indicates that the UE will enter the DRX period.

State 3: The UE uses a long DRX cycle, and drx-InactivityTimer starts running; contrary to State 2, this state means that the UE successfully decodes the PDCCH during operation, ie does not enter the DRX period and enters the continuous reception state.

State 4: The UE starts to use the long DRX cycle and the system frame number (SFN) at that time and the corresponding subframe. Through this state, it can be inferred which subframe or which time the UE starts working.

State 5: The UE starts to use the short DRX cycle; Corresponding to state 1, if the UE configures a short DRX cycle, the drx-InactivityTimer count expires or the DRX Command MAC control element is received, the UE will start using the short cycle.

State 6: The UE uses a short DRX cycle, and the onDurationTimer expires during operation, and the drx-InactivityTimer does not run, that is, the PDCCH is not successfully decoded during operation.

State 7: The UE uses the short DRX cycle, and the drx-InactivityTimer starts running. Similarly, this state means that the UE successfully decodes the PDCCH during the work, that is, it does not enter the DRX period and enters the continuous reception state.

State 8: The UE uses the short DRX cycle and the SFN and subframe at that time. From this state, it can be inferred which subframe of the UE or which time is in operation, and is in an ON state.

State 9: The UE uses a long DRX cycle. When the onDurationTimer expires, the drx-InactivityTimer does not run. This state means that the UE did not successfully decode the PDCCH during On, ie the UE will enter the DRX period. If the HARQ loop timer, that is, the HARQ RTT Timer or the DRX retransmission timer, that is, the drx-Retransmission Timer is running, the HARQ RTT Time and the drx-RetransmissionTimer are transmitted. This will determine when the user will start the state to receive HARQ retransmissions.

State 10: The UE uses a short DRX cycle. When the onDurationTimer expires, the drx-InactivityTimer does not run. This state means that the UE does not successfully decode the PDCCH during On, ie the UE will enter the DRX. Time period. If the HARQ RTT Timer or drx-RetransmissionTimer is running, the HARQ RTT Time and the drx-RetransmissionTimer are transmitted. This will determine when the user will start the state to receive HARQ retransmissions.

Through the above state information, it can be directly determined that the UE enters the continuous reception state (starting state) for a base station to enter a discontinuous reception state (ie, a DRX period) and/or to end a discontinuous reception state (ie, a DRX period). For example, the state 2 or the state 6 can directly know that the user enters the long DRX period and the short DRX period.

It is known by state 3 or state 7 that the user directly enters the continuous reception state. If combined with the base station's DRX configuration information for the UE, it can determine the moment when the UE enters the discontinuous reception (ie, the DRX period) and/or the end discontinuous reception (ie, the DRX period) enters the continuous reception (starting state). ). For example, by receiving state 4, it is determined that the on-duration period (ie, on duration), then enters the DRX period after the OnDurationTimer expires, and combines the long DRX cycle obtained by the interaction, if there is no Upon receipt of state 3, then enters the working period (i.e., on duration) after the end of the long DRX cycle, and if state 3 is received, then the continuous reception state is entered.

Through the foregoing one status information or multiple status information, it is possible to directly determine or infer that the UE enters a continuous reception state for a base station to enter a discontinuous reception state (ie, a DRX period) and/or to end a discontinuous reception state (ie, a DRX period) ( Startup state). The process can be done by the base The algorithm design of the station is completed, and the present invention aims to provide a method for a base station to acquire the DRX status information of the user to another base station.

The present invention proposes a coordination mechanism for DRX information between a UE, a MeNB, and an SeNB in a dual connectivity system. Based on the mechanism, one base station in the dual connectivity system can determine that another base station is in a discontinuous reception state and continuously receives. The state, thus scheduling, causes the non-continuous reception states of the two base stations to be aligned to achieve power saving. At the same time, dynamic management of the power of the UE can be realized, and the transmission efficiency of the system can be improved.

It is to be understood by those skilled in the art that the above-described state is for illustrative purposes only and is not intended to limit the scope of application of the present invention. Those of ordinary skill in the art will also appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments of the present application can be implemented as an electronic hardware, a computer software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described in terms of their functionality. Whether this function is implemented as a hardware or as a software depends on the particular application and design constraints imposed on the overall system. A person skilled in the art can implement the described functions in a modified manner for each specific application, but such implementation decisions should not be construed as departing from the scope of the invention.

Claims (15)

A method for coordinating DRX information of a user equipment in a dual connectivity system includes: A: a primary base station and a secondary base station acquire DRX status information of the user equipment; B: the primary base station interacts with the secondary base station The DRX configuration information of the user equipment. The method of claim 1, wherein the step A further comprises: when a base station of the primary base station and the secondary base station determines that the user equipment enters the DRX state corresponding to the base station, The base station transmits the DRX status information of the user equipment to another base station of the primary base station and the secondary base station; or the user equipment corresponds to one of the primary base station and the secondary base station The DRX status information is sent to the other base station. The method of claim 1, wherein one of the primary base station and the secondary base station is based on a DRX state of the user equipment corresponding to another base station and/or the user equipment corresponds to another base station. The DRX configuration information can determine when the user equipment corresponds to another base station entering a discontinuous reception and/or ending a discontinuous reception into a continuous reception. The method of claim 3, wherein the DRX state is that the user equipment enters a discontinuous reception state corresponding to another base station and/or ends a discontinuous reception state and/or enters a continuous reception state. The method of claim 1, wherein the primary base station transmits its DRX configuration information to the secondary base station through the added secondary base station message sent to the secondary base station, and/or the primary base station Receiving DRX configuration information or DRX reconfiguration information of the secondary base station by receiving the secondary base station cell modification information of the secondary base station; and/or when one of the primary base station or the secondary base station performs its DRX configuration During reconfiguration, one of the primary base station or the secondary base station transmits its reconfigured DRX configuration information and/or the DRX status information of the user equipment to another base in the primary base station or secondary base station. station. A method for coordinating DRX information of a user equipment in a primary base station of a dual connectivity system, comprising: A: receiving first information indicating that the user equipment is in a DRX state of the secondary base station, or transmitting the determined information The second information indicating the DRX status of the user equipment for the primary base station to the secondary base station; B: the primary base station interacts with the secondary base station for DRX configuration information of the user equipment. The method of claim 6, wherein the method further comprises: the primary base station receiving the first information from the user equipment or the secondary base station; or the primary base station receiving the secondary base The first information sent by the station together with the DRX configuration information reconfigured by the secondary base station. As in the method described in claim 6, the step B is also The method includes: the primary base station sends the DRX configuration information to the secondary base station through the supplementary secondary base station message of the secondary base station; and/or the primary base station modifies the information by receiving the secondary base station cell of the secondary base station Receiving DRX configuration information of the secondary base station or DRX configuration information of the secondary base station reconfiguration. The method of claim 6, wherein when the primary base station reconfigures its DRX configuration, the primary base station transmits its reconfigured DRX configuration information to the secondary base station; or the primary The base station transmits its reconfigured DRX configuration information to the secondary base station along with the second information. A method for coordinating DRX information of a user equipment in a secondary base station of a dual connectivity system, comprising: A: receiving third information indicating that the user equipment enters a DRX state for a primary base station, or transmitting the determination thereof The fourth information indicating the DRX status of the user equipment for the secondary base station to the primary base station; B: the secondary base station interacts with the primary base station for DRX configuration information of the user equipment. The method of claim 10, wherein the method further comprises: the secondary base station receiving the third information from the user equipment or the primary base station; or The secondary base station receives the DRX configuration information and the third information that are reconfigured by the primary base station and sent by the primary base station. The method of claim 10, wherein the step B further comprises: the secondary base station receiving the DRX of the primary base station by adding information from the secondary base station receiving the secondary base station of the primary base station And configuring the information; and/or the secondary base station sends the DRX configuration information of the secondary base station or the DRX configuration information of the secondary base station reconfiguration by sending the secondary base station cell modification information of the secondary base station to the primary base station. The method of claim 10, wherein when the secondary base station reconfigures its DRX configuration, the secondary base station transmits its reconfigured DRX configuration information to the primary together with the fourth information. Base station. The method of claim 10, wherein the step B further comprises: the secondary base station receiving the DRX configuration information of the primary base station reconfiguration. A method for coordinating DRX information in a user equipment of a dual connectivity system includes: when the user equipment enters a DRX state corresponding to the first base station, the user equipment sends a user equipment to indicate the user equipment Enter the first information of the DRX state to the second base station.