CN101064681A

CN101064681A - Long term evolvement network and method for executing operation indication of MAC layer therein

Info

Publication number: CN101064681A
Application number: CNA2006100796276A
Authority: CN
Inventors: 胡灏
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2006-04-28
Filing date: 2006-04-28
Publication date: 2007-10-31

Abstract

The invention relates to the field of mobile communication, and discloses a long-term evolution network and a method for performing an operation instruction on a MAC layer, so that user equipment in an uplink asynchronous state can correctly receive information from a network side. In the present invention, on the network side, when the MAC layer receives an operation instruction from the upper layer for the user equipment in the active state, if the user equipment is in the uplink synchronization state, then directly execute the operation instruction; if the user equipment is in the uplink asynchronous state, then The MAC layer paging is initiated to the user equipment, and the MAC layer executes the operation instruction after the user completes the uplink synchronization process according to the MAC layer paging.

Description

Long term evolution network and method for MAC layer to execute operation indication

Technical Field

The present invention relates to the field of mobile communications, and in particular, to a Long Term Evolution (LTE) network.

Background

Mobile communication technology has been rapidly developed since The end of The 20 th century into The Second Generation mobile communication (The Second Generation, abbreviated as "2G"). However, as the number of users increases and the demands for service types and performance increase, 2G gradually shows limitations in terms of data transmission capabilities and the like. Therefore, The Third Generation (3G for short) mobile communication with stronger data transmission capability enters a high-speed development stage, and The mobile communication field presents a gradual transition from 2G to 3G.

While 3G systems are gradually coming into commercial use, the industry has begun research work on new technologies. Some companies refer to these new technologies as Super 3G (Super 3G) technologies, and some refer to them as 3.9G technologies. The data service transmission rate of the 3.9G technology will reach about 100Mbps, and a large number of advanced technologies, such as Orthogonal Frequency Division Multiplexing (OFDM for short) and Multiple Input Multiple Output (MIMO for short), are introduced, and are collectively referred to as 3G evolution technology, that is, E3G technology in China.

In order to standardize the E3G technology, 3rd Generation Partnership Project (3 GPP) and 3GPP2 have begun respective research works in tandem since the end of 2004.

With the introduction of Enhanced technologies such as High Speed Downlink Packet Access (HSDPA), Enhanced Uplink (Enhanced Uplink), and the like, 3GPP radio Access technologies have High competitiveness in the next few years. However, to ensure competitiveness for some longer time (e.g., 10 years or longer), 3GPP started the LTE project from the second half year of 2004.

One of the important matters in the discussion of LTE networks by the standards organization is the state partitioning of the protocols. At present, according to a resource condition used by a User Equipment (UE) in a moving process and a contact degree with a network side, the UE is divided into three states, namely, a separated state (LTE _ detached), an idle state (LTE _ idle), and an active state (LTE _ active), which respectively correspond to three similar states in an existing Wideband Code Division Multiple Access (WCDMA) network: a detached state, an idle state, and a connected state (connected). Since LTE does not currently form a practical standard, there may be different names for the three states, but it is essentially identical. Generally speaking, in the detached state, the network side considers that the UE has left the network, and typically the UE is powered off; in an idle state, the UE logs in the network but is not connected to the network side, and the network side knows the approximate location of the UE and can find the UE through paging, typically, the UE is in a standby state; in the active state, the UE has a connection with the network side, and typically the UE is using a wireless service, such as making a call.

In the conventional WCDMA system, when the UE is in an idle state, a CELL paging channel (CELL _ PCH) state, and a radio access paging channel (URA _ PCH) state, the UE receives data from the network side in a Discontinuous Reception (DRX) manner for power saving. Specifically, the UE in the idle state, the CELL _ PCH state, and the URA _ PCH state monitors a Paging Indicator (PI) on a Paging Indicator Channel (PICH) at one Paging occasion (Paging occasion) in each DRX cycle. The paging time is calculated according to the DRX value, and the PI to be read by the UE at the paging time is calculated according to an International Mobile Station Identity (IMSI) of the UE. And if the PI indicates that the paging information belongs to the UE when the UE monitors the PICH, the UE receives the corresponding paging information through the PCCH. In order to enable the UE to accurately receive the paging message from the network side, the network side and the UE negotiate the DRX parameters in advance, so that the network side can send PI at a proper time, and the UE can find and receive the PI information belonging to the UE on the PICH at a corresponding time.

For the connected UEs, including the UEs in the CELL dedicated channel (CELL _ DCH) and CELL forward access channel (CELL _ FACH) states, the paging message is sent through the Dedicated Control Channel (DCCH), and since the UEs in the CELL _ DCH and CELL _ FACH states continuously receive data on the DCCH channel, the paging message from the network side can be received in time.

In LTE, however, since there is no dedicated channel, in the active state, the UE also receives and transmits data in a DRX/DTX (discontinuous reception/transmission) manner. When data needs to be sent to the UE, the network side needs to initiate a paging command to establish a downlink between the UE and the network side. That is to say, when there is data to be sent to the UE, the network side issues a paging message with the UE at a paging time according to a DRX cycle in an active state negotiated with the UE, as shown in fig. 1, correspondingly, the UE determines and receives the paging message sent to itself by monitoring a Shared Control Channel (SCCH) or a PI on a PICH, and establishes communication with the network side after receiving the paging message.

In practical applications, the above scheme has the following problems: the existing paging method cannot ensure that the UE in an activated state correctly receives the paging message from the network side.

The main reason for this is that in the LTE architecture, if there is no data transmission for the UE in the active state for a period of time or the UE is in a discontinuous reception state for a long time, in order to save power consumption of the UE and save air interface resources, the UE may enter a state that does not maintain uplink synchronization, and the UE in the active state may be further classified into an "uplink synchronization state" and an "uplink asynchronous state" according to whether the uplink synchronization is performed. However, whether the UE is in the uplink synchronous state or the uplink asynchronous state is only known at a Medium Access Control (MAC) layer level, but is not known to a network side RRC layer in the prior art, which is responsible for initiating and constructing a paging message. In this case, when the network side needs to send data to the UE, although the network side still sends the paging message at the paging time according to the DRX cycle in the active state negotiated with the UE, the UE does not monitor the paging indication on the SCCH or PICH at the negotiated fixed paging time, which may cause call loss, and the security of data transmission is not guaranteed.

Disclosure of Invention

In view of the above, the present invention provides a long term evolution network and a method for performing operation indication in a MAC layer thereof, so that a ue in an uplink asynchronous state can correctly receive information from a network side.

In order to achieve the above object, the present invention provides a method for an MAC layer to execute an operation instruction in a long term evolution network, comprising the following steps:

on the network side, when the MAC layer receives the operation instruction to the user equipment in the activated state from the upper layer, the MAC layer judges whether the user equipment is in the uplink synchronization state, if so, the operation instruction is directly executed, otherwise, MAC layer paging is initiated to the user equipment to instruct the user equipment to execute the uplink synchronization process, and the operation instruction is executed after the user equipment completes the uplink synchronization.

And after the network side MAC layer receives a response message for the MAC layer paging from the user equipment, the user equipment is judged to finish uplink synchronization.

In addition, in the method, when initiating the paging, the MAC layer initiates MAC layer paging to the user equipment in a serving cell of the user equipment according to the location information of the user equipment obtained from the upper layer.

In addition, in the method, if the MAC layer of the network side does not receive the response message from the ue within a predetermined time after initiating the MAC layer paging to the ue, the upper layer is notified that the ue cannot execute the operation instruction.

In addition, in the method, the upper layer is a radio resource control layer.

Further in the method, the operation indication is an operation primitive.

Further in the method, the operation indication includes a data transmission indication, an inquiry indication, and a paging indication.

In addition, in the method, after receiving the MAC layer paging, if the ue is in an uplink asynchronous state, the ue first performs an uplink synchronization procedure, and then sends a response message to the MAC layer paging to the network side and establishes communication with the network side.

In addition, the method also comprises the following steps:

for the user equipment in the uplink synchronization state in the activated state, the network side and the MAC layer of the user equipment detect the data transmission and scheduling conditions on the channel between the network side and the user equipment, if the detection result meets the preset condition, the user equipment does not keep the uplink synchronization with the network side any more, and the network side and the MAC layer of the user equipment record that the user equipment is in the uplink asynchronous state.

Further in the method, the preset conditions include:

in a preset length of time, the user equipment does not have uplink data transmission, and the downlink data transmission of the user equipment by a network side is lower than a preset threshold value; or,

and in the time with the preset length, no uplink and downlink data transmission exists between the user equipment and the network side.

The invention also provides a long-term evolution network, and the network side MAC layer comprises:

the judging module is used for judging whether the user equipment is in an uplink synchronous state;

the execution module is used for executing operation instructions from an upper layer to the user equipment;

the paging module is used for initiating MAC layer paging to the user equipment;

the judging module judges whether the user equipment is in an uplink synchronization state or not when receiving an operation instruction of an upper layer to the user equipment in an activated state, if so, the executing module is instructed to directly execute the operation instruction, otherwise, the paging module is instructed to initiate MAC layer paging to the user equipment, the user equipment is triggered to execute an uplink synchronization process, and the executing module is instructed to execute the operation instruction after the user equipment completes the uplink synchronization.

The main difference between the technical solution of the present invention and the prior art can be found by comparing, in the network side, when the MAC layer receives the operation instruction of the upper layer to the user equipment in the active state, if the user equipment is in the uplink synchronization state, the operation instruction is directly executed, if the user equipment is in the uplink asynchronous state, the paging of the MAC layer is initiated to the user equipment, and after the user finishes the uplink synchronization process according to the MAC layer paging, the MAC layer executes the operation instruction again. When the network side needs to send data or page to the user equipment in the uplink asynchronous state, the user equipment can be quickly and accurately found through the paging message of the MAC layer, the uplink synchronous process is executed through the user equipment, communication between the network side and the user equipment is established, and the user equipment in the uplink asynchronous state can also correctly receive information from the network side. Because the maintenance of the uplink synchronous state and the uplink asynchronous state is completed in the MAC layer, an upper layer (e.g., RRC layer) of the MAC layer only needs to know whether the ue is in an active state, and does not need to further know whether the ue belongs to the uplink synchronous state or the uplink asynchronous state.

The MAC layer of the network side initiates paging to the user equipment in the service cell of the user equipment according to the position information of the user equipment obtained from the upper layer, thereby ensuring that the network side can accurately find the user equipment through the paging information.

Drawings

Fig. 1 is a diagram illustrating a network side sending a paging message to a UE in the prior art;

fig. 2 is a flowchart of a method for performing operation indication by a MAC layer in an LTE network according to a first embodiment of the present invention;

fig. 3 is a flowchart of a method for indicating operation performed by a MAC layer in an LTE network according to a second embodiment of the present invention;

fig. 4 is a flowchart of a method for performing operation indication by a MAC layer in an LTE network according to a third embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.

The core of the present invention is that, on the network side, when the MAC layer receives an operation instruction from an upper layer (typically, an RRC layer) to the UE in an active state, different execution modes are adopted according to whether the UE is currently in an uplink synchronization state. If the UE is currently in an uplink synchronization state, the MAC layer directly executes an operation instruction from an upper layer; if the UE is currently in the uplink asynchronous state, the MAC layer firstly initiates paging of the MAC layer to the UE, and after the UE completes an uplink synchronous process according to the paging of the MAC layer, operation instructions are executed. The method avoids the MAC layer directly executing the operation instruction to the UE in the uplink asynchronous state, and effectively prevents the UE from generating unnecessary errors due to the fact that the UE cannot correctly respond to the operation of the MAC layer in the non-uplink synchronous state.

The following describes a method for performing operation instruction by the MAC layer in the LTE network according to the first embodiment of the present invention.

In this embodiment, for a UE in an uplink synchronization state in an active state, a network side and an MAC layer of the UE detect data transmission and scheduling conditions on a channel between the network side and the UE, and if a detection result meets a preset condition, the UE no longer maintains uplink synchronization with the network side and enters the uplink asynchronous state in the active state, and the network side and the MAC layer of the UE respectively record that the UE is in the uplink asynchronous state. The preset condition may be that the UE has no uplink data transmission within a predetermined length of time, and downlink data transmission to the UE by the network side is lower than a preset threshold; or, there is no uplink and downlink data transmission between the UE and the network side within a predetermined length of time. This embodiment mainly describes different execution methods of the MAC layer for the UE in the uplink synchronized state and the uplink asynchronous state when receiving a data transmission instruction from the RRC layer, which is an upper layer.

As shown in fig. 2, after receiving the data transmission instruction from the RRC layer to the active UE, the MAC layer proceeds to step 210, and determines, according to the record of the MAC layer, that the UE is currently in the uplink synchronous state or the uplink asynchronous state of the active UE. If the UE is currently in the uplink asynchronous state, step 220 is entered, otherwise, step 260 is entered directly. Because the maintenance and judgment of the uplink synchronous state and the uplink asynchronous state of the UE are finished in the MAC layer, the RRC layer only needs to know whether the UE is in the activated state, and does not need to further know whether the UE belongs to the uplink synchronous state or the uplink asynchronous state, thereby simplifying the processing of the RRC layer, ensuring that the UE achieves the purposes of power saving and the like by utilizing the uplink asynchronous state and avoiding increasing the burden of the RRC layer.

Since the UE is currently in the uplink asynchronous state, step 220 is entered, and the MAC layer initiates MAC layer paging to the UE in the serving cell of the UE according to the location information of the UE obtained from the RRC layer, which ensures that the MAC layer can accurately find the UE through the paging message to the maximum extent.

If the UE receives the MAC layer paging, the uplink synchronization process is executed according to the prior art, and a response message to the MAC layer paging is returned to the network side.

Then step 230 is entered, the MAC layer on the network side determines whether a response message of the UE to the MAC layer paging has been received currently, if the response message is received, it is determined that the UE has completed uplink synchronization, step 260 is entered, otherwise, step 240 is entered, it is further determined whether the time for receiving the MAC layer response message exceeds a preset time, if the preset time has not been reached, step 230 is returned, the UE continues to wait for receiving the response message of the UE to the MAC layer paging, if the preset time has been reached, and the MAC layer has not received the response message from the UE, it is determined that the UE is lost, step 250 is entered, and the RRC layer is notified that the data transmission instruction cannot be executed to the UE.

When the MAC layer determines that the UE is in the synchronization state, including the case that the UE is originally in the synchronization state, or the UE enters the synchronization state after receiving the MAC layer paging message from the network side and performing the uplink synchronization process, the method proceeds to step 260, and the MAC layer performs a data transmission instruction for the UE and transmits corresponding downlink data to the UE. When receiving the data transmission instruction to the UE in the uplink asynchronous state, the MAC layer does not directly execute the instruction, but transmits the MAC layer paging message to the UE in the uplink asynchronous state, and executes the data transmission instruction after the uplink synchronization is completed. When the network side needs to send data to the UE in the uplink asynchronous state, the UE can be quickly and accurately found through the paging message of the MAC layer, the uplink synchronous process is executed through the UE, communication between the network side and the UE is established, and the UE in the uplink asynchronous state can also be ensured to correctly receive information from the network side.

A second embodiment of the present invention describes a method for performing a paging instruction on a UE in an uplink synchronous state and an uplink asynchronous state when a MAC layer in an LTE network receives a paging instruction from an RRC layer (the instruction instructs the MAC layer to initiate MAC layer paging on a designated UE).

As shown in fig. 3, when a network side needs to initiate paging to a UE in an active state, an RRC layer issues a paging instruction to an MAC layer, and after receiving the paging instruction, the MAC layer enters step 310 to determine, according to a record of the MAC layer, an uplink synchronous state or an uplink asynchronous state of the UE in the active state. If the UE is currently in the uplink asynchronous state, go to step 330, otherwise, if the UE is currently in the uplink synchronous state, go to step 320, where the MAC layer directly executes the paging indication, and initiates MAC layer paging to the UE in the serving cell of the UE according to the location information of the UE obtained from the RRC layer.

Since the UE is currently in the uplink asynchronous state, step 330 is entered, and the MAC layer initiates paging of the MAC layer to the UE in the serving cell of the UE according to the location information of the UE obtained from the RRC layer.

After the UE receives the MAC layer paging from the network side, if the UE is in an uplink asynchronous state, uplink synchronization is completed according to the prior art, a response message for the MAC layer paging is returned to the network side, and communication with the network side is established; otherwise, directly returning a response message to the network side to establish communication with the network side.

After step 320 or step 330, step 340 is then entered, the MAC layer on the network side determines whether a response message of the UE to the MAC layer paging has been received currently, if the response message is received, step 370 is entered, the response of the UE is notified to the RRC layer and the process is ended, if the response message is not received yet, step 350 is entered, it is further determined whether the time for receiving the MAC layer response message exceeds a preset duration, if the preset duration has not been reached, step 340 is returned, the UE continues to wait for receiving the response message of the UE to the MAC layer paging, if the preset duration has been reached, and the MAC layer has not received the response message from the UE, it is determined that the UE is lost, step 360 is entered, and the RRC layer is notified that the UE cannot be paged.

A third embodiment of the present invention describes a method for performing an inquiry instruction on a UE in an uplink synchronous state and an uplink asynchronous state when an MAC layer in an LTE network receives an inquiry instruction from an RRC layer.

As shown in fig. 4, in step 410, before the RRC layer needs to initiate RRC layer paging to the UE in an active state, the RRC layer first sends an inquiry instruction to the MAC layer to inquire the current state of the UE.

Then, step 420 is entered, the MAC layer receives the query instruction from the RRC layer, and determines the uplink synchronous state or uplink asynchronous state of the UE currently in the active state according to the record of the MAC layer. If the UE is currently in the uplink asynchronous state, step 430 is entered, otherwise, step 450 is directly entered, the MAC layer returns a message that the UE is in the normal state to the RRC layer, and the RRC layer initiates RRC layer paging to the UE according to the prior art. Because the RRC layer does not know or should not know the MAC layer state (uplink synchronization state or uplink asynchronous state) of the UE in the active state, the MAC layer returns an inquiry result to the RRC layer when the UE is in the uplink synchronization state, that is, the UE is normal, instead of the UE being in the uplink synchronization state. The RRC layer understands the query result of "normal UE" as that the current state of the UE completely conforms to the active state definition of the RRC layer, wherein the definition of the current state of the UE corresponds to the uplink synchronization state. Of course, the query result of "UE normal" may have other names, which are the same as the meaning of the present invention, and do not necessarily have the same name as the present invention.

Since the UE is currently in the uplink asynchronous state, step 430 is entered, and the MAC layer initiates MAC layer paging to the UE in the serving cell of the UE according to the location information of the UE obtained from the RRC layer.

Step 440 is entered, the MAC layer of the network side determines whether a response message of the UE to the MAC layer paging has been received currently, if the response message has been received, it determines that the UE has completed uplink synchronization, step 450 is entered, the MAC layer returns a message that the UE is in a normal state to the RRC layer, and the RRC layer initiates RRC layer paging to the UE according to the prior art; otherwise, step 460 is entered, and it is further determined whether the time for receiving the MAC layer response message exceeds the preset duration, if the preset duration has not been reached, step 440 is returned, the UE continues to wait for receiving the response message for paging the MAC layer from the UE, and if the preset duration has been reached and the MAC layer has not received the response message from the UE, it is determined that the UE is lost, step 470 is entered, and as an operation result of the query indication, the RRC layer is notified that the UE cannot be found.

The network side MAC layer in the fourth embodiment of the present invention includes a determining module for determining whether the UE is in an uplink synchronization state, an executing module for executing an operation instruction from an upper layer to the UE, and a paging module for initiating MAC layer paging to the UE.

Specifically, when receiving an operation instruction of an upper layer to the UE in an active state, the MAC layer determines, by using the determining module, whether the UE is in an uplink synchronization state, and if so, instructs the executing module to directly execute the operation instruction, otherwise, instructs the paging module to initiate MAC layer paging to the UE, triggers the UE to execute an uplink synchronization process, and instructs the executing module to execute the operation instruction after the UE completes the uplink synchronization.

The determining module, the executing module and the paging module in the fourth embodiment are logical concepts, and may be physically implemented in different modules or implemented in the same module. The determining module, the executing module and the paging module may have various names, but the effect of the present invention can be achieved as long as the functions are provided, and the present invention belongs to the protection scope of the present invention. It can be understood that the functions related in the judging module, the executing module and the paging module are mainly status judgment, execution operation indication and paging initiation, and these functions are all easily realized by the known technology, but the present prior art does not realize the purpose of the present invention by the creative combination of these functions.

The operation instruction referred to in the above embodiments is only for instructing the MAC layer to perform a certain operation, and the operation instruction may be implemented in the form of an operation primitive or the like, and may have other names.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. A method for performing operation indication at a MAC layer in a long term evolution network, comprising the steps of:

2. The method of claim 1, wherein the MAC layer determines that the ue has completed uplink synchronization after the network MAC layer receives a response message from the ue to the MAC layer paging.

3. The method of claim 1, wherein the MAC layer initiates MAC layer paging to the ue in a serving cell of the ue according to the location information of the ue obtained from the upper layer when the MAC layer initiates the paging.

4. The method of claim 1, wherein if the MAC layer of the network side does not receive the response message from the ue within a predetermined time after initiating MAC layer paging to the ue, the MAC layer notifies the upper layer that the ue cannot execute the operation instruction.

5. The method of claim 1, wherein the upper layer is a radio resource control layer.

6. Method for performing operation indication by the MAC layer in a long term evolution network according to any of claims 1 to 5 characterized in that the operation indication is an operation primitive.

7. The method of any of claims 1 to 5, wherein the operation indication comprises a data transmission indication, an inquiry indication, and a paging indication.

8. The method according to any of claims 1 to 5, wherein after receiving the MAC layer page, if the UE is in uplink asynchronous state, the UE performs uplink synchronization process, and then sends a response message to the MAC layer page to the network side and establishes communication with the network side.

9. The method for performing operation indication by the MAC layer in the lte network according to any of claims 1 to 5, further comprising the following steps:

10. The method of claim 9, wherein the preset condition comprises:

11. A long term evolution network, wherein a network side MAC layer comprises: