CN102740443B

CN102740443B - The acquisition methods of auxiliary timing lead and equipment

Info

Publication number: CN102740443B
Application number: CN201110084167.7A
Authority: CN
Inventors: 曾清海; 黄曲芳
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Filing date: 2011-04-02
Publication date: 2016-12-14
Anticipated expiration: 2031-04-02

Abstract

The embodiment of the present invention provides acquisition methods and the equipment of a kind of auxiliary timing lead.Method includes: terminal is after receiving assisted cell activation command, or, after described assisted cell is activated, if the non-cutting time of described assisted cell aligns, intervalometer TAT does not run, initiating random access procedure, the auxiliary timing lead TA of described assisted cell is different from the main TA of main plot；Described terminal obtains described auxiliary TA according to the TA received in described random access procedure.The acquisition methods of the auxiliary timing lead that the embodiment of the present invention provides and equipment, terminal is receiving the activation assisted cell order that base station sends, or after assisted cell is activated, initiating random access procedure is to obtain auxiliary timing lead, thus saving signaling expense and system resource.

Description

Method and device for acquiring secondary timing advance

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and a device for acquiring a secondary timing advance.

Background

The Long Term Evolution (LTE) system is The next-Generation wireless communication standard developed and established by The 3GPP (The3rd Generation Partnership Project), and has The advantages of high spectrum utilization rate and transmission speed, low transmission delay and The like. The terminal of the LTE system realizes synchronization of uplink transmission with the base station by Timing Advance (TA), and maintains uplink synchronization by a Time Alignment Timer (TAT). The introduction of TA enables the uplink transmission of all terminals to be achieved at the time expected by the base station, thereby avoiding the uplink transmission conflict among the terminals and realizing time division multiplexing.

In order to provide a higher data rate, the base station may further configure one or more Secondary cells (scells) for the terminal to perform data transmission, where the Primary Cell and each Secondary Cell correspond to an uplink carrier, and transmission on different uplink carriers may need to use different TAs. The TA corresponding to the primary cell is called primary TA, the TAT corresponding to the primary cell is called primary TAT, the TA of the secondary cell is called secondary TA, and the TAT of the secondary cell is called secondary TAT.

In the prior art, after configuring the secondary cell, if the secondary cell does not use the existing TA of the primary cell, the terminal initiates random access in the secondary cell to acquire the secondary TA of the secondary cell, which may increase signaling overhead in the random access process and the TA maintenance process and waste system resources.

Disclosure of Invention

The embodiment of the invention provides a method and equipment for acquiring auxiliary Timing Advance (TA), which can reduce signaling overhead and save system resources when acquiring the auxiliary TA.

The embodiment of the invention provides a method for acquiring a secondary timing advance, which comprises the following steps:

after receiving a secondary cell activation command or after the secondary cell activation, if a secondary Time Alignment Timer (TAT) of the secondary cell is not running, a terminal initiates a random access process, wherein a secondary Timing Advance (TA) of the secondary cell is different from a primary TA of a primary cell;

and the terminal acquires the auxiliary TA according to the TA received in the random access process.

The embodiment of the invention also provides another method for acquiring the auxiliary timing advance, which comprises the following steps:

sending an auxiliary cell activation command to a terminal; according to the random access initiated by the terminal, sending TA to the terminal in the random access process; the random access is initiated by the terminal after receiving the auxiliary cell activation command or after confirming the activation of the auxiliary cell according to the auxiliary cell activation command, if the auxiliary TAT of the auxiliary cell is not operated, the auxiliary TA of the auxiliary cell is different from the primary TA of the primary cell.

The embodiment of the invention also provides an uplink out-of-step processing method, which comprises the following steps: the terminal starts an auxiliary TAT of the configured auxiliary cell; if the TAT of the auxiliary cell is overtime, the terminal informs a base station, and/or stops uplink transmission on the auxiliary cell, and/or activates the auxiliary cell.

An embodiment of the present invention further provides a terminal, including:

a receiving unit, configured to receive a secondary cell activation command, where a secondary timing advance TA of the secondary cell is different from a primary TA of a primary cell;

a random access unit, configured to initiate a random access process if a secondary time alignment timer TAT of the secondary cell is not running after the receiving unit receives the secondary cell random access command or after the secondary cell is activated;

an obtaining unit, configured to obtain the auxiliary TA according to the TA received in the random access procedure. An embodiment of the present invention further provides a base station, including:

and the first sending unit is used for sending the auxiliary cell activation command to the terminal.

A second sending unit, configured to send a TA to the terminal in the random access process according to random access initiated by the terminal; the random access is initiated by the terminal after receiving the auxiliary cell activation command or after confirming the activation of the auxiliary cell according to the auxiliary cell activation command, if the auxiliary TAT of the auxiliary cell is not operated, the auxiliary TA of the auxiliary cell is different from the primary TA of the primary cell.

An embodiment of the present invention further provides a terminal, including: a starting unit, configured to start an auxiliary TAT according to the acquired auxiliary TA; and the processing unit is used for informing the base station that the auxiliary TAT is overtime if the auxiliary TAT is overtime, and/or stopping uplink transmission in an auxiliary cell corresponding to the auxiliary TAT, and/or deactivating the auxiliary cell corresponding to the auxiliary TAT.

According to the method and the device for acquiring the auxiliary timing advance, the terminal initiates a random access process to acquire the auxiliary timing advance after receiving the command of activating the auxiliary cell or after the auxiliary cell is activated, so that signaling overhead and system resources are saved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a flowchart of an embodiment of a method for acquiring a secondary timing advance according to the present invention;

fig. 2 is a flowchart of another embodiment of a method for acquiring a secondary timing advance according to the present invention;

fig. 3 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention;

fig. 4 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention;

fig. 5 is a flowchart of a method for acquiring a secondary timing advance according to still another embodiment of the present invention;

fig. 6 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention;

FIG. 7 is a schematic diagram of acquiring an assisted TA in the embodiment provided in FIG. 6;

FIG. 8 is a flowchart illustrating a method for acquiring a secondary timing advance according to another embodiment of the present invention

FIG. 9 is a schematic diagram of acquisition assistance TA in the embodiment provided in FIG. 8;

fig. 10 is a flowchart of an uplink out-of-step processing method provided in the embodiment of the present invention;

FIG. 11 is a schematic structural diagram of one embodiment of a terminal provided by the present invention;

fig. 12 is a schematic structural diagram of another embodiment of the terminal provided by the present invention;

fig. 13 is a schematic structural diagram of an embodiment of a base station provided in the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the embodiment of the present invention, the Base Station may be an evolved Node B (eNB), a Base Station (BS), a Node B, an access point (access point), and the like. The base station may be a macro base station, a medium base station, or a micro base station, such as a home base station. Each base station may provide communication coverage for a particular geographic area. The term "cell" can be a coverage area of a base station, and/or a coverage area serviced by a base station subsystem, depending on the context in which the term is used. A base station may provide communication coverage for a macrocell, a picocell (pico cell), a femtocell (femto cell), and/or other types of cells.

In embodiments of the present invention, the terminals may be distributed throughout the wireless network, and each terminal may be static or mobile. A terminal (terminal) may be a user equipment (user equipment; U E), a Mobile Station (MS), a subscriber unit (subscriber unit), a station (station), etc. The terminal may also be a cellular telephone (cellular phone), a Personal Digital Assistant (PDA), a wireless modem (modem), a wireless communication device, a handheld device (hand held), a laptop computer (laptop computer), a cordless telephone (cordless phone), a Wireless Local Loop (WLL) station, or the like. The terminal can communicate with base stations such as macro base stations, pico base stations, femto base stations and the like. The terminal may further include a communication device communicating with the base station and having a similar terminal role, for example, a Relay Node (RN) initially accesses the network, and the RN and the base station access the network as one terminal when communicating.

Fig. 1 is a flowchart of an embodiment of a method for acquiring a secondary timing advance provided by the present invention, as shown in fig. 1, the method includes:

s101, after receiving an auxiliary cell activation command or after the auxiliary cell is activated, if an auxiliary TAT of the auxiliary cell is not operated, a terminal initiates a random access process, wherein an auxiliary TA of the auxiliary cell is different from a main TA of a main cell;

s102, the terminal acquires the auxiliary TA according to the TA received in the random access process.

The base station may carry the TA in message 2 of the random access procedure sent to the terminal. The terminal may start the TAT after acquiring the TA. And during the operation of the TAT, the terminal is in an uplink synchronization state. In the embodiment of the present invention, the base station may further calibrate the TA by sending a Medium Access Control (MAC) layer Timing Advance Command (Timing Advance Command), so as to synchronize uplink transmission of the terminal with the base station. And the terminal restarts the TAT according to the TA calibration value received from the TA command so as to always keep the uplink transmission synchronous with the base station.

In the embodiment of the present invention, the terminal receives the auxiliary cell activation command, and the auxiliary cell may be already activated or may not be activated, and after receiving the auxiliary cell activation command, the terminal may initiate a random access procedure if the auxiliary TAT of the auxiliary cell is not running regardless of whether the auxiliary cell is already activated. Or after receiving the auxiliary cell activation command, the terminal may wait for the confirmation of the activation of the auxiliary cell, and then initiate a random access procedure if the auxiliary TAT of the auxiliary cell is not running.

In this embodiment, the secondary TA of the secondary cell may be different from the primary TA of the primary cell, i.e. not belong to the same TA Group (TAG). When there are multiple secondary cells, the secondary TAs of the multiple secondary cells may be different from the primary TA of the primary cell, and the secondary TAs of the secondary cells may be the same. For example, if a secondary cell having a Physical Random Access Channel (PRACH) resource is different from a primary TA of a primary cell, a terminal may initiate a Random Access procedure on the secondary cell with the PRACH resource as a reference cell. When there are multiple secondary cells with different secondary TAs from the primary TA of the primary cell, and the secondary TAs of the multiple secondary cells are the same, if at least one of the multiple secondary cells has PRACH resources, the terminal may initiate a random access procedure on the secondary cell with the secondary cell having PRACH resources as a reference cell. The reference cell is used for referencing a downlink carrier of the reference cell when the terminal sends a preamble (preamble) in a process of initiating the random access.

In the embodiment provided by the invention, after the terminal receives the auxiliary cell activation command or after the auxiliary cell is activated, if the auxiliary TAT of the auxiliary cell is not running, the terminal may initiate a random access procedure to acquire the auxiliary TA of the auxiliary cell. The terminal may initiate the random access immediately after receiving the auxiliary cell activation command or after the auxiliary cell activation if the auxiliary TAT of the auxiliary cell is not running, or the terminal may not initiate the random access actively but may initiate the random access triggered by the base station, for example, the terminal may initiate the random access process according to the random access command after receiving the auxiliary cell activation command or after the auxiliary cell activation if the auxiliary TAT of the auxiliary cell is not running. If the reference cell is indicated in the random access command sent by the base station, the terminal may initiate a random access procedure on an auxiliary cell having PRACH resources according to the indicated reference cell (that is, in the process of initiating the random access by the terminal, the terminal sends a preamble with reference to a downlink carrier of the reference cell indicated by the base station); if the reference cell is not indicated in the random access command, the terminal may initiate a random access procedure on the cell carrying the random access command by using the cell carrying the random access command as the reference cell. In the embodiment of the invention, the terminal can also set a random access timer, after receiving the activation command of the auxiliary cell or after the activation of the auxiliary cell, the auxiliary TAT of the auxiliary cell does not run, if the random access command is received within the time length set by the random access timer, the terminal can initiate random access according to the reference cell indicated by the random access command or initiate a random access process on the cell bearing the random access command; if the random access command is not received after the set duration of the random access timer is exceeded, the terminal may initiate a random access procedure on the supplementary cell with the supplementary cell as a reference cell. The random access method comprises the steps that through a random access timer, the time set by the random access timer is waited, if a random access command is received in the set time, a random access process is initiated according to the random access command, otherwise, if the random access command is not received in the set time, the random access is initiated after the set time is overtime.

When the terminal initiates random access on the secondary cell to obtain the secondary TA, the secondary TA may be a TA received by the terminal in a random access procedure. For example, the base station may send a message 2(message 2) of the random access procedure to the terminal in the random access procedure, that is, a response message of the random access procedure, where the TA is carried in the message 2. It can be understood that, in the embodiment of the present invention, the TA may also be carried in other messages sent by the base station to the terminal in the random access procedure.

In addition, in the embodiment of the present invention, the terminal may further initiate a random access procedure on the secondary cell by using the primary cell as a reference cell, and in this case, the secondary TA acquired by the terminal may not be a TA sent in the random access procedure, and the secondary TA acquired by the terminal may be a sum of a difference between a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell and a sum of a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell, where the secondary TA sent by the base station is a TA acquired secondary TA received in the random access procedure. Or, the secondary TA acquired by the terminal may be a difference value between 2 times of the TA received in the random access procedure and the primary cell TA. Similarly, the base station may also carry the TA in the message 2 of the random access procedure sent to the terminal in the random access procedure, or carry the TA in another message sent to the terminal in the random access procedure.

In the embodiment of the present invention, when all the secondary cells of the terminal do not have PRACH resources, the terminal may further initiate a random access procedure on the primary cell with the secondary cell as a reference cell. In this case, the auxiliary TA acquired by the terminal may be a sum of a difference between a timing value of the auxiliary cell downlink carrier and a timing value of the main cell downlink carrier and a TA sent by the base station in the random access process; or the secondary TA acquired by the terminal may be a difference value between 2 times of the TA received in the random access procedure and the primary cell TA.

In the method for acquiring the secondary timing advance provided in this embodiment, when the secondary TA of the secondary cell needs to be acquired, the terminal may not initiate the random access process arbitrarily, and the terminal may receive a command to activate the secondary cell, or, after the secondary cell is activated, initiate the random access process to acquire the secondary timing advance, so that unnecessary signaling overhead and waste of system resources in the random access process and the TA maintenance process when the secondary cell is in a deactivated state may be avoided, thereby saving the signaling overhead and the system resources.

Fig. 2 is a flowchart of another embodiment of a method for acquiring a secondary timing advance provided by the present invention, as shown in fig. 2, the method includes:

s201, sending a secondary cell activation command to the terminal.

S202, according to the random access initiated by the terminal, sending TA to the terminal in the process of random access; the random access is initiated by the terminal after receiving the auxiliary cell activation command or after confirming the activation of the auxiliary cell according to the auxiliary cell activation command, if the auxiliary TAT of the auxiliary cell is not operated, the auxiliary TA of the auxiliary cell is different from the primary TA of the primary cell.

In this embodiment, after sending the TA to the terminal through the random access procedure, the terminal may acquire the supplementary TA.

The main body of the above steps can be the base station.

In the embodiment provided by the present invention, the base station sends the auxiliary cell activation command to the terminal, and the terminal may initiate a random access procedure to acquire the auxiliary TA of the auxiliary cell after receiving the auxiliary cell activation command or after the auxiliary cell activation if the auxiliary TAT of the auxiliary cell is not running.

In this embodiment, the terminal may use the auxiliary cell with the PRACH resource as a reference cell, initiate a random access procedure on the auxiliary cell, and the auxiliary TA acquired by the terminal may be a TA that is sent to the terminal by the base station in the random access procedure. Or, the terminal may also initiate a random access procedure on the secondary cell with the primary cell as a reference cell. Or, when all the secondary cells of the terminal do not have PRACH resources, the terminal may also initiate a random access procedure on the primary cell with the secondary cell as a reference cell. In this embodiment, the process of the terminal initiating the random access may refer to the method in the embodiment shown in fig. 1.

Fig. 3 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention, as shown in fig. 3, after receiving a secondary cell activation command, or after a secondary cell is activated, if an auxiliary TAT of the secondary cell is not running, the secondary cell is used as a reference cell, and a terminal initiates a random access procedure on the secondary cell to acquire a secondary TA of the secondary cell. It should be noted that, for multiple secondary cells with the same secondary TA, at least one of the secondary cells needs to have PRACH resources, so that the terminal may initiate a random access procedure on the secondary cell with PRACH resources.

S301, the base station configures a plurality of auxiliary cells for the terminal.

In this embodiment, for example, two secondary cells, SCell1 and SCell2, respectively, and indicate that SCell1 and the primary cell belong to the same TA group, i.e., TAG 1; SCell2 belongs to another TA group, i.e., TAG 2. Since SCell2 does not employ a primary TA, the terminal needs to acquire a secondary TA corresponding to SCell2, i.e., TA 2. Additionally, the base station may indicate that there is PRACH resource on SCell 2.

S302, the terminal receives an auxiliary cell activation command sent by the base station.

For example: the base station may carry an auxiliary cell Activation command in an Activation/Deactivation media Control Element (Activation/Deactivation MAC Control Element). The secondary cell activation command may be used to simultaneously activate secondary cell SCell1 and SCell 2.

And S303, the terminal initiates a random access process on the PRACH of the SCell2 by taking the SCell2 as a reference cell.

After activating SCell2, the terminal may initiate a random access procedure to acquire a secondary TA of SCell, TA2, if it finds that a secondary TAT for SCell2, TAT2, is not running. The terminal uses SCell2 as a reference cell, that is, the terminal uses a downlink carrier of SCell2 as a reference, when the terminal selects PRACH of an uplink subframe n of SCell2 to transmit a preamble, a start transmission time of the preamble is a start reception time of the downlink subframe n corresponding to SCell2, where n may be a non-negative integer identifying a subframe or a symbol or character identifying a subframe.

S304, the terminal acquires the auxiliary TA according to the information in the random access process.

The terminal receives a message 2 of a random access process sent by the base station, where the message 2 of the random access process carries a TA, and TA2 acquired by the terminal can be the TA carried in the message 2, so that the terminal can start a TAT 2.

In this embodiment, a secondary TA acquisition procedure of the secondary cell SCell2 that does not use the primary TA is provided, and if the base station further configures another secondary cell belonging to the same TA group as the SCell2 for the terminal, the TA acquisition procedures of the other secondary cells may use the method provided in this embodiment. If the base station also configures other secondary cells which do not belong to the same TA group as SCell2 for the terminal, the terminal also needs to initiate a random access procedure on the secondary cell with PRACH resource to acquire the secondary TAs corresponding to other secondary cells, when the corresponding secondary TAT is not running after the other secondary cells are activated.

It should be noted that, in this embodiment, when the terminal actively initiates the random access procedure, it needs to compete with other terminals for PRACH resources, so the random access procedure may fail. If the terminal fails to initiate the random access procedure, the terminal may continue to initiate the random access procedure on the PRACH of the SCell2 with the SCell2 as a reference cell until the random access is successful or the number of times of initiating the random access exceeds a maximum value.

Fig. 4 is a flowchart of a method for acquiring a secondary timing advance according to still another embodiment of the present invention, as shown in fig. 4, in this embodiment, after receiving an auxiliary cell activation command or after activating an auxiliary cell, an auxiliary TAT of the auxiliary cell is not run, a terminal does not immediately initiate random access, but after receiving a random access command sent by a base station, the terminal may use a cell bearing the random access command as a reference cell, and initiate a random access procedure on the reference cell to acquire an auxiliary TA of the auxiliary cell. It should be noted that the secondary cell carrying the random access command has PRACH resource, so that the terminal may initiate a random access procedure on the secondary cell.

S401, the base station configures an auxiliary cell for the terminal.

In this embodiment, the base station may configure secondary cell SCell1 for the terminal and indicate that SCell1 and primary cell PCell do not belong to the same TA group, and SCell1 belongs to another TA group, i.e., TAG 2. In addition, the base station indicates that there is PRACH resource on SCell 1.

S402, the terminal receives an auxiliary cell activation command sent by the base station.

This command is used to activate the secondary cell SCell 1.

S403, the terminal receives the random access command on SCell 1.

The random access command received by the terminal may be, for example, a physical downlink Control Channel Order (PDCCH Order).

Since the base station indicates that there is PRACH resource on SCell1, the base station may employ a random access command to trigger the terminal to initiate a random access procedure on SCell 1.

S404, the terminal initiates a random access procedure on SCell1 with SCell1 as a reference cell.

S405, the terminal acquires the auxiliary TA according to the information in the random access process.

The terminal receives a message 2 of a random access process sent by the base station, the message 2 of the random access process carries a TA, and an auxiliary TA of the Scell acquired by the terminal is the TA carried in the message 2, so that the terminal can start an auxiliary TAT corresponding to the SCell.

Fig. 5 is a flowchart of a method for acquiring a secondary timing advance according to still another embodiment of the present invention, as shown in fig. 5, in this embodiment, after receiving a secondary cell activation command or after activating a secondary cell, if an auxiliary TAT of the secondary cell is not running, a terminal starts a random access timer. If the terminal receives a random access command which is sent by the base station and used for acquiring the TA of the auxiliary cell before the random access timer is overtime, the terminal stops the timer and initiates random access on the auxiliary cell bearing the command or a cell indicated by the random access command according to the random access command sent by the base station; if the terminal does not receive the random access command sent by the base station before the random access timer times out, the terminal may initiate a random access procedure to acquire a corresponding TA with the auxiliary cell as a reference cell, but the premise is that the auxiliary cell initiating the random access procedure needs to have PRACH resources.

S501, the base station configures an auxiliary cell for the terminal.

S502, the terminal receives an auxiliary cell activation command sent by the base station, or after the auxiliary cell is activated, the terminal starts a random access timer.

Wherein the secondary cell activation command is used to activate the secondary cell SCell 1.

S503, before the random access timer expires, the terminal does not receive the random access command sent by the base station on SCell1, and then the terminal initiates a random access procedure on SCell1 with SCell1 as a reference cell.

S504, the terminal receives the message of the random access process sent by the base station and acquires the auxiliary TA.

The terminal receives a message 2 of a random access process sent by the base station, the message 2 of the random access process carries a TA, and an auxiliary TA of the Scell acquired by the terminal can be the TA carried in the message 2, so that the terminal can start an auxiliary TAT corresponding to the Scell.

It should be noted that, if the terminal receives the random access command sent by the base station for the TAG2 before the random access timer expires, if the random access command explicitly indicates the reference cell or the TA to be acquired, the terminal may initiate a random access procedure on an auxiliary cell of the auxiliary TA to be acquired to acquire the TA by using the cell indicated in the random access command as the reference cell, provided that the auxiliary cell initiating the random access procedure has PRACH resources. If the reference cell is not explicitly indicated in the random access command, the terminal may initiate a random access procedure on the reference cell to acquire the secondary TA with the cell carrying the random access command as the reference cell.

Fig. 6 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention, as shown in fig. 6, in this embodiment, after receiving an auxiliary cell activation command or after an auxiliary cell is activated, the auxiliary cell does not have PRACH resources. If the auxiliary TAT of the secondary cell is not running, the terminal may initiate a random access procedure on the primary cell to acquire the TA with the secondary cell as a reference cell. Wherein auxiliary TA _ msg2+ delta, or 2^＊TA _ msg2-TA _ pcell. Wherein, TA _ msg2 is a TA carried in message 2 of the random access process, delta is a difference between a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell, and TA _ pcell is a TA of the primary cell.

S601, the base station configures an auxiliary cell for the terminal.

In this embodiment, the base station configures a secondary cell SCell1 for the terminal, and indicates that SCell1 and primary cell PCell do not belong to the same TA group, and SCell1 belongs to another TA group, i.e., TAG 2.

S602, the terminal receives an auxiliary cell activation command sent by the base station.

The secondary cell activation command may be used to activate the secondary cell SCell 1.

S603, the terminal takes the SCell1 as a reference cell and initiates a random access process on a primary cell PCell.

After receiving the secondary cell activation command sent by the base station or after activating the SCell1, the terminal may initiate a random access procedure to acquire a secondary TA of the SCell if the terminal finds that the secondary TAT of the SCell1 is not running. The terminal uses the Scell1 as a reference cell, that is, the terminal uses the downlink carrier of the Scell1 as a reference, when the terminal selects the PRACH of the PCell uplink subframe n to transmit the preamble, the transmission start time of the preamble is the reception start time of the downlink subframe n corresponding to the Scell1, and n may be a non-negative integer identifying a subframe or a symbol or character identifying a subframe.

S604, the terminal receives the message of the random access process sent by the base station and acquires the auxiliary TA.

And the terminal receives the message 2 of the random access process sent by the base station, and calculates the auxiliary TA of the Scell1 according to the TA carried in the message 2 of the random access process, so that the auxiliary TAT of the Scell can be started.

Fig. 7 is a schematic diagram of acquisition assistance TA in the embodiment provided in fig. 6, and a calculation method of TA2 is shown in fig. 7:

in fig. 7, Msg1 is message 1(message 1) in the random access procedure, which may include a preamble, and the eNB is an evolved NodeB (evolved NodeB).

TA2 TA _ msg2+ delta or TA 22 × TA _ msg2-TA _ pcell. The TA _ msg2 is a TA carried in message 2 of the random access process, the delta is a difference between timing values of a downlink carrier of the secondary cell and a downlink carrier of the primary cell, and the TA _ pcell is a TA of the primary cell.

Fig. 8 is a flowchart of a method for acquiring a secondary timing advance according to another embodiment of the present invention, as shown in fig. 8, in this embodiment, after receiving a secondary cell activation command or after a secondary cell activation, if a secondary TAT of the secondary cell is not running, a terminal may use a primary cell as a reference cell and use the primary cell as a reference cell on the secondary cellA random access procedure is initiated to acquire the TA. The auxiliary TA _ msg2+ delta or 2^＊TA _ msg2-TA _ pcell. Wherein, TA _ msg2 is a TA carried in message 2 of the random access process, delta is a difference between a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell, and TA _ pcell is a TA of the primary cell.

S701, the base station configures an auxiliary cell for the terminal.

In this embodiment, the base station may configure secondary cell SCell1 for the terminal and indicate that SCell1 and primary cell PCell do not belong to the same TA group, and SCell1 belongs to another TA group, i.e., TAG 2.

S702, the terminal receives an auxiliary cell activation command sent by the base station.

This command is used to activate the secondary cell SCell 1.

And S703, the terminal takes the primary cell PCell as a reference cell and initiates a random access process on the SCell 1.

After receiving a secondary cell activation command sent by a base station or activating the SCell1, if the terminal finds that the secondary TAT of the SCell1 is not running, the terminal may initiate a random access procedure to acquire the secondary TA of the SCell. The terminal uses the PCell as a reference cell, that is, the terminal uses the downlink carrier of the PCell as a reference, when the terminal selects the PRACH (preamble) of the SCell1 uplink subframe n to transmit the preamble, the transmission start time of the preamble is the reception start time of the downlink subframe n corresponding to the PCell, and n may be a non-negative integer for identifying a subframe or a symbol or character for identifying a subframe.

S704, the terminal receives the message of the random access process sent by the base station and acquires the auxiliary TA.

And the terminal receives the message 2 of the random access process sent by the base station, and acquires the auxiliary TA2 of the Scell1 according to the TA carried in the message 2 of the random access process, so that the auxiliary TAT of the Scell can be started.

Fig. 9 is a schematic diagram of acquiring an auxiliary TA in the embodiment provided in fig. 8, and a calculation method of TA2 is shown in fig. 9:

in fig. 9, Msg1 is a message 1 in a random access procedure, which may include a preamble, and the eNB is an evolved NodeB (evolved NodeB).

TA2 ═ TA _ msg2+ delta or TA2 ═ 2 × TA _ msg2-TA _ pcell or TA2 ═ TA _ pcell +2 × delta. Wherein, TA _ msg2 is the TA indicated by message 2 of the random access procedure, delta is the difference between the timing values of the downlink carrier of the secondary cell and the downlink carrier of the primary cell, and TA _ pcell is the TA of the primary cell.

In the prior art, if the auxiliary TAT times out, the terminal will flush all buffers (buffers) of the uplink Hybrid Automatic Repeat Request (HARQ), empty resources of the uplink and downlink semi-persistent scheduling, and notify a Radio Resource Control (RRC) layer to release Physical Uplink Control Channel (PUCCH) and/or Sounding Reference Signal (SRS) resources. But this will cause PUCCH, SRS and semi-persistent scheduling resources to be released erroneously, thereby affecting data transmission. Moreover, before the base station knows that the uplink of the secondary cell is out of synchronization, the base station may continue to schedule the out-of-synchronization secondary cell, thereby causing resource waste, and may cause uplink collision due to the application of an invalid secondary TA.

The embodiment of the invention also provides a method for solving the problems of resource waste and uplink conflict caused by that PUCCH, SRS and semi-static scheduling resources are released by mistake to influence data transmission and the base station schedules out-of-step auxiliary cells in the prior art. Fig. 10 is a flowchart of an uplink out-of-step processing method provided by the present invention, and as shown in fig. 10, the method specifically includes:

s801, the terminal starts an auxiliary TAT of the configured auxiliary cell.

S802, if the auxiliary TAT of the auxiliary cell is overtime, the terminal informs the base station, and/or stops uplink transmission on the auxiliary cell, and/or activates the auxiliary cell.

In this embodiment of the present invention, for example, the terminal may obtain the secondary TA of the secondary cell according to the method provided in the above method for obtaining the secondary timing advance, so as to start the secondary TAT of the secondary cell.

For example, the base station configures secondary cell1 and SCell2 for the terminal and activates SCell1 and SCell2, the base station indicates in the configuration message that SCell1 and SCell2 belong to TAG2, and the terminal starts the secondary TATs, i.e., TAT2, for SCell1 and SCell 2. If TAT2 times out, the terminal informs the base station, and/or stops all uplink transmissions on SCell1 and SCell2, and/or deactivates SCell1 and SCell 2.

The terminal can inform the base station of uplink desynchronization caused by the timeout of TAT2 on the primary cell or other uplink synchronized secondary cells through RRC signaling (which can be newly defined RRC signaling) or Media Access Control Component Element (MAC CE) or Physical layer (PHY) signaling. The terminal may also stop all uplink transmissions, and specifically may stop transmissions including a physical uplink shared channel PUSCH, a physical uplink control channel PUCCH, and a Sounding reference signal SRS. Thereby avoiding resource waste and possible uplink collision.

It should be noted that the method may be used in cooperation with the method for acquiring the secondary timing advance provided by the embodiment of the present invention, so as to save signaling overhead and system resources, and avoid resource waste and possible uplink collision.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above may be implemented by a computer program instructing associated hardware, or may be implemented by a chip or a processor, and the program may be stored in a computer readable storage medium, and when executed, may include the processes of the embodiments of the methods described above. The storage medium may be a magnetic disk, an optical disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), or the like.

Fig. 11 is a schematic structural diagram of an embodiment of a terminal provided by the present invention, where the terminal provided by the embodiment of the present invention may be applied to the method embodiment provided by the foregoing embodiment of the present invention, as shown in fig. 11, the terminal includes: a receiving unit 11, a random access unit 12 and an acquisition unit 13;

a receiving unit 11, configured to receive a secondary cell activation command, where a secondary timing advance TA of the secondary cell is different from a primary TA of a primary cell;

a random access unit 12, configured to initiate a random access process after the receiving unit 11 receives the random access command of the secondary cell, or after the secondary cell is activated, if the secondary time alignment timer TAT of the secondary cell is not running;

an obtaining unit 13, configured to obtain the auxiliary TA according to the TA received in the random access procedure.

After the receiving unit 11 receives the auxiliary cell activation command sent by the base station, or after the auxiliary cell is activated, if the auxiliary TAT of the auxiliary cell is not running, the random access unit 12 may initiate a random access procedure to obtain the auxiliary TA of the auxiliary cell. The random access unit 12 may initiate a random access immediately after the receiving unit 11 receives an auxiliary cell activation command sent by the base station, or after the auxiliary cell is activated, if the auxiliary TAT of the auxiliary cell is not running, or the random access unit 12 may initiate the random access not actively but triggered by the receiving station, for example, after the terminal receives the random access command, initiate a random access process according to the random access command. Or, the random access unit 12 may also determine random access according to a duration set by a set random access timer, and if the terminal receives a random access command within the duration set by the random access timer, the random access unit 12 may initiate random access according to a reference cell indicated by the random access command, or initiate random access on a cell carrying the random access command; if the random access command is not received for a period longer than the time set by the random access timer, the random access unit 12 may initiate random access on the secondary cell with the secondary cell as a reference cell.

If the secondary cell that the secondary cell and the primary cell do not belong to the same TA group has PRACH resources, or at least one of the plurality of secondary cells that the secondary TA and the primary TA of the primary cell do not belong to the same TA group has PRACH resources, the random access unit 12 may initiate a random access procedure on the secondary cell with the secondary cell having PRACH resources as a reference cell.

The random access process initiated by the random access unit 12 may be initiated actively, or may also be initiated under the trigger of the base station, and the receiving unit 11 may also receive a random access command sent by the base station, for example, the random access unit 12 initiates the random access process according to the received random access command sent by the base station. The random access unit 12 may initiate a random access procedure on the auxiliary cell having the PRACH resource according to the indicated reference cell; or the cell carrying the random access command can be used as a reference cell, and the random access process is initiated on the cell carrying the random access command. In addition, the terminal may include a random access timer, and if the random access command sent by the base station is not received after the duration set by the random access timer unit exceeds the duration set by the random access timer unit, the random access unit 12 may still initiate a random access procedure on the auxiliary cell with the auxiliary cell as a reference cell. When initiating a random access in the secondary cell, the secondary TA obtained by the obtaining unit 13 may be a TA received in a random access procedure.

In addition, the random access unit 12 may also initiate a random access procedure on the secondary cell with the primary cell as a reference cell, in this case, the secondary TA acquired by the acquisition unit 13 may not be a TA sent by the base station in the random access procedure, and the secondary TA acquired by the terminal may be a difference between a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell, and a sum of a timing value of a downlink carrier of the secondary cell and a timing value of a downlink carrier of the primary cell and a timing value of a secondary TA received by the TA sent by the base station in the random access procedure. Alternatively, the secondary TA acquired by the acquiring unit 13 may be a difference value between 2 times of the TA received in the random access procedure and the primary cell TA.

When all the secondary cells of the terminal do not have PRACH resources, the random access unit 12 may also initiate a random access procedure on the primary cell with the secondary cell as a reference cell. In this case, the auxiliary TA acquired by the acquiring unit 13 may be a sum of a difference between a timing value of the auxiliary cell downlink carrier and a timing value of the main cell downlink carrier and a TA sent by the base station in the random access process; or the secondary TA acquired by the acquiring unit 13 may be a difference value between 2 times of the TA received in the random access procedure and the primary cell TA.

In the terminal provided by this embodiment, the terminal initiates a random access procedure to acquire the secondary timing advance after receiving the command for activating the secondary cell sent by the base station or after the secondary cell is activated, so as to save signaling overhead and system resources.

Fig. 12 is a schematic structural diagram of another embodiment of a terminal provided by the present invention, and the terminal provided by the embodiment of the present invention may be applied to the method embodiment provided by the above-mentioned embodiment of the present invention, as shown in fig. 12, the terminal includes: a receiving unit 11, a random access unit 12 and an acquisition unit 13;

further, the random access unit 12 is specifically configured to: and initiating a random access process on the auxiliary cell by taking the auxiliary cell as a reference cell.

The receiving unit 11 may also be configured to: and receiving a random access command sent by the base station.

If the receiving unit 11 receives the random access command indicating the reference cell;

accordingly, the random access unit 12 may be configured to: and initiating a random access process on the auxiliary cell according to the reference cell indicated in the random access command.

The random access unit 12 may also be configured to: and initiating a random access process on the cell carrying the random access command by taking the cell carrying the random access command as a reference cell.

The terminal provided in this embodiment may further include: a random access timer 14, configured to start after the receiving unit receives 11 an auxiliary cell activation command sent by the base station, or after the auxiliary cell is activated;

the random access unit 12 is specifically configured to: if the random access command sent by the base station is not received after the set time length of the random access timer 14 is exceeded, the random access process is initiated on the auxiliary cell by taking the auxiliary cell as a reference cell.

The auxiliary TA acquired by the acquiring unit 13 is a TA received in the random access process.

The random access unit 12 may also be configured to: initiating a random access process on the auxiliary cell by taking the main cell as a reference cell; or, the auxiliary cell is taken as a reference cell, and the random access process is initiated on the main cell.

Correspondingly, the auxiliary TA acquired by the acquiring unit 13 is the sum of the difference values of the timing values of the receiving TA, the auxiliary cell downlink carrier and the main cell downlink carrier in the random access process; or the difference between twice the received TA in the random access procedure and the TA of the primary cell.

The random access unit 12 is further configured to: and in the process of initiating the random access, the downlink carrier of the reference cell is used as a reference when the lead code is sent.

The terminal provided by the embodiment of the invention can also comprise: a starting unit 15;

a starting unit 15, configured to start the auxiliary TAT according to the auxiliary TA acquired by the acquiring unit 13

The processing unit 16 is configured to notify the base station that the auxiliary TAT is overtime if the auxiliary TAT is overtime, and/or stop performing uplink transmission in an auxiliary cell corresponding to the auxiliary TAT, and/or deactivate the auxiliary cell corresponding to the auxiliary TAT.

Embodiments of the present invention may also provide a terminal, which may include the starting unit 15 and the processing unit 16 shown in fig. 12. The terminal may obtain the supplementary TA of the supplementary cell through the method embodiment for obtaining the TA provided in the embodiment of the present invention.

On the basis of the previous embodiment, a random access timer 14 may be set, and if the receiving unit 11 does not receive the random access command sent by the base station when the set duration of the random access timer 14 is exceeded, the random access unit 12 may still initiate a random access procedure on the secondary cell, or on other secondary cells that share the same secondary TA and have PRACH resources, with the secondary cell being a reference cell. In this case, the TA sent by the base station and received by the acquiring unit 13 in the random access process is the auxiliary TA.

The terminal provided in the embodiment of the present invention is an execution device of the method for acquiring secondary timing advance provided in the embodiment of the present invention, and corresponds to the method for acquiring secondary timing advance provided in the embodiment of the present invention, and specific processes for executing the method for acquiring secondary timing advance may refer to method embodiments, which are not described herein again.

The terminal provided by the embodiment of the invention initiates a random access process to acquire the auxiliary timing advance after receiving the auxiliary cell activating command or the auxiliary cell activation sent by the base station, thereby saving signaling overhead and system resources.

Fig. 13 is a schematic structural diagram of an embodiment of a base station provided in the present invention, where the base station provided in the embodiment of the present invention may be applied to the method embodiment provided in the foregoing embodiment of the present invention, and as shown in fig. 13, the base station includes: a first transmission unit 21 and a second transmission unit 22;

a first sending unit 21, configured to send a secondary cell activation command to the terminal.

A second sending unit 22, configured to send a TA to the terminal in the random access process according to the random access initiated by the terminal; the random access is initiated by the terminal after receiving the auxiliary cell activation command or after confirming the activation of the auxiliary cell according to the auxiliary cell activation command, if the auxiliary TAT of the auxiliary cell is not operated, the auxiliary TA of the auxiliary cell is different from the primary TA of the primary cell.

In this embodiment, after the second transmitting unit 22 transmits the TA to the terminal, the terminal may acquire the supplementary TA.

The first sending unit 21 may be further configured to: before the terminal initiates a random access process, sending a random access command to the terminal so that the terminal initiates the random access process on a cell bearing the random access command by taking the cell bearing the random access command as a reference cell; and if the reference cell is indicated in the random access command, the terminal initiates a random access process on the auxiliary cell according to the reference cell indicated in the random access command.

And sending the TA to the terminal as the auxiliary TA in the random access process.

The first sending unit 21 may be further configured to: before the terminal initiates a random access process, sending a random access command to the terminal so that the terminal initiates the random access process on the auxiliary cell by taking the main cell as a reference cell; or the terminal initiates a random access process on the primary cell by taking the secondary cell as a reference cell.

In this embodiment, the terminal may be the terminal in the embodiment shown in fig. 11 and 12.

The base station provided in the embodiment of the present invention is an apparatus for executing the method for acquiring secondary timing advance provided in the embodiment of the present invention, and corresponds to the method for acquiring secondary timing advance provided in the embodiment of the present invention, and specific processes for executing the method for acquiring secondary timing advance may be referred to in the method embodiment, and are not described herein again.

The base station provided by the embodiment of the invention initiates a random access process to acquire the auxiliary timing advance after receiving the auxiliary cell activating command or the auxiliary cell activation sent by the base station, thereby saving signaling overhead and system resources.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for acquiring a secondary Timing Advance (TA) is characterized by comprising the following steps:

after a secondary cell is activated, if a secondary Time Alignment Timer (TAT) of the secondary cell is not operated, if a terminal receives a random access command, the terminal initiates a random access process according to the random access command, wherein a secondary TA of the secondary cell is different from a primary TA of a primary cell;

2. The method of claim 1, wherein the initiating a random access procedure according to the random access command comprises:

initiating a random access process on the auxiliary cell according to the reference cell indicated in the random access command; or,

and the terminal initiates a random access process on the cell bearing the random access command by taking the cell bearing the random access command as a reference cell.

3. The method of claim 1, wherein the auxiliary TA is a TA received in the random access procedure.

4. The method according to claim 1, wherein the initiating the random access procedure specifically is:

initiating a random access process on the auxiliary cell by taking the main cell as a reference cell; or,

and initiating a random access process on the main cell by taking the auxiliary cell as a reference cell.

5. The method according to claim 4, wherein the auxiliary TA is a sum of a difference value between a timing value of the downlink carrier of the auxiliary cell and a timing value of the downlink carrier of the primary cell and a TA received in the random access procedure; or,

the auxiliary TA is a difference value between two times of the TA received in the random access process and the TA of the primary cell.

6. The method of claim 1, further comprising:

starting an auxiliary TAT of the auxiliary cell according to the auxiliary TA;

and if the auxiliary TAT is overtime, stopping uplink transmission in an auxiliary cell corresponding to the auxiliary TAT.

7. A communication terminal, comprising:

a random access unit, configured to, after an auxiliary cell is activated, if an auxiliary time alignment timer TAT of the auxiliary cell is not running, if a receiving unit receives a random access command, initiate a random access process according to the random access command;

an obtaining unit, configured to obtain the auxiliary TA according to a timing advance TA received in the random access process;

a receiving unit, configured to receive a random access command sent by a base station;

wherein the secondary timing advance TA of the secondary cell is different from the primary TA of the primary cell.

8. The terminal of claim 7, wherein the random access unit is further configured to: initiating a random access process on the auxiliary cell according to the reference cell indicated in the random access command; or, taking the cell carrying the random access command as a reference cell, and initiating a random access process on the cell carrying the random access command.

9. The terminal of claim 7, wherein the auxiliary TA acquired by the acquiring unit is a TA received in the random access procedure.

10. The terminal of claim 7, wherein the random access unit is further configured to: initiating a random access process on the auxiliary cell by taking the main cell as a reference cell; or, initiating a random access procedure on the primary cell by taking the secondary cell as a reference cell.

11. The terminal according to claim 10, wherein the auxiliary TA obtained by the obtaining unit is a sum of a difference between a timing value of the downlink carrier of the auxiliary cell and a timing value of the downlink carrier of the primary cell and a received TA in the random access procedure; or the auxiliary TA acquired by the acquiring unit is a difference between twice the TA received in the random access procedure and the TA of the primary cell.

12. The terminal of claim 7, further comprising:

a starting unit, configured to start the auxiliary TAT according to the auxiliary TA acquired by the acquiring unit;

and the processing unit is used for stopping uplink transmission in the auxiliary cell corresponding to the auxiliary TAT if the auxiliary TAT is overtime.