JP6500931B2 - Method for maintaining timing advance timer, base station and terminal device - Google Patents

Description

  The present invention relates to the field of communications, and more particularly, to a method of maintaining a timing advance timer, a base station and a terminal device.

  In Rel. 10 LTE-A (LTE-Advanced, Long Term Evolution-Advanced, Long Term Evolution Advanced) system, uplink synchronization must be guaranteed in order to realize uplink communication. The process of achieving uplink synchronization includes the following steps, as shown in FIG.

  S1: The terminal transmits a signal in uplink. This signal may be an uplink random access preamble signal transmitted to a process in which the terminal performs random access, or may be a data signal.

  S2: Based on the received signal, the base station determines whether it is necessary to adjust the uplink signal of the terminal, and if it is necessary to adjust, it is necessary to either advance the time or to delay the time It is necessary to judge further. Based on the determination result, the base station transmits a timing advance command TAC (Timing Advance Command) on the downlink. By the timing advance command, the base station notifies the terminal of the amount (advance amount or delay amount) necessary for advancing time or delaying time. The timing advance command transmitted by the base station is included in different downlink information based on the type of signal (terminal data or random access preamble signal) transmitted by the terminal in uplink. If the terminal transmits on the uplink is a random access preamble signal, the timing advance command is included in random access response information. If it is a data signal that the terminal transmits in uplink, the timing advance command is a control cell of one MAC (Media Access Control) layer.

  S3: After receiving the timing advance command, the terminal advances or delays the uplink transmission time by a corresponding amount based on the instruction of the timing advance command. At the same time, the terminal needs to maintain one timing advance timer. If the timing advance timer is activated, the terminal recognizes that its uplink is in synchronization. If this timing advance timer expires, the terminal recognizes that the uplink has lost synchronization. In this case, the terminal clears all the HARQ (Hybrid Automatic Repeat Request, Hybrid automatic retransmission request) buffer, and in the RRC (Radio Resource Control, Radio Resource Control) layer, the PUCCH (Physical Uplink Control Channel, Physical uplink control channel). And release SRS (Sounding Reference Signal), and clear any configured downlink assignment and uplink grant. There is a need. When it is necessary to transmit new uplink or downlink data after the uplink loses synchronization, the terminal has to perform a random access process, reestablish uplink synchronization, and restart the timing advance timer.

  At the moment, activation of the timing advance timer is divided into the following several cases. The terminal starts or restarts the timing advance timer when it receives the MAC control cell of the timing advance command; the random access preamble is selected by the MAC layer of the terminal when the timing advance command is included in the random access response information Otherwise, start or restart the timing advance timer; if the timing advance command is included in the random access response information but the random access preamble is to be selected by the MAC layer of the terminal, the timing advance timer is activated If not, start the timing advance timer, and if the contention in the random access process is not resolved, stop the timing advance timer; and Another case when grayed advance command is included in the random access response information, ignoring the timing advance command received.

  For a single-band system, uplink carriers in the same band transmitted by the same terminal may be recognized as coincident when their receiving end is in the same position, ie the uplink is adjusted If there is one carrier achieving synchronization, the uplink can also achieve synchronization if other carriers in the same band make the same adjustment as this carrier. Therefore, in such a single band system, uplink measurement may be performed on only one of the uplinks, and similar adjustments may be performed on other carriers based on the measurement results. Thus, uplink synchronization of the entire band can be maintained, so that the terminal need only maintain one timing advance timer.

  However, in a multi-band carrier aggregation system, since there is a relatively large difference in uplink transmission between different bands, there may be a difference in uplink synchronization adjustment for carriers of different bands. In such a case, different time adjustment amounts need to be transmitted for carriers of different bands, and in some cases, there may be simultaneous transmission of multiple timing advance commands for multiple bands. At the same time, the terminal may maintain multiple timing advance timers for multiple bands or may maintain only one timing advance timer.

  Therefore, for a multi-band carrier aggregation system, how to maintain multiple or one timing advance timer by the base station or terminal becomes a problem that needs to be solved.

  FIG. 2 is a diagram showing a plurality of TATs in a multi-band carrier aggregation system. As shown in FIG. 2, in the multi-band carrier aggregation system of this embodiment, the base station allocates three bands to the terminal as an example. Among them, Primary Cell (PCell, Primary Cell) and Secondary Cell 1 (SCell, Secondary Cell) are in Band 0, Secondary Cells 1 and 2 are in Band 1, and Secondary Cell 3 is in Band 2. In this embodiment, it is taken as an example that the terminal corresponds to these three bands by three different TATs.

  As shown in FIG. 2, if maintenance can be completely independent for these three TATs, although TAT 0 is operating, when TAT 1 has expired, based on the uplink maintenance process, the terminal can It is necessary to clear the HARQ buffer in band 1 and release the dedicated resource corresponding to the carrier in band 1 in the PUCCH and the SRS corresponding to the carrier in band 1. These operations relate to communication in this band only and do not affect communication in other bands. Similarly, when TAT2 is expired, the operation of the terminal affects only the communication of Band2. However, although TAT 0 has expired, when both TAT 1 and TAT 2 are operating, the terminal determines that the PCell uplink has lost synchronization, and PUCCH transmits only on the PCell uplink. At this time, since the PUCCH can not perform uplink transmission at this time, the communication of the entire terminal is affected, and effective communication can not be performed. In such a case, the loss of synchronization in one band causes an interruption in the communication of the entire terminal.

  If TAT 0 is working, but TAT 1 or TAT 2 has expired, this may be recognized as a kind of normal phenomenon, because, in some cases, the base station will Based on the determination, it may be determined that one terminal does not need much more bands, and may intentionally cause the uplink synchronization of such bands to be lost and release resources for other terminals. is there. However, if TAT 1 and TAT 2 are both working, but TAT 0 is dead, this is a kind of a case to avoid.

  FIG. 3 is a diagram showing single TAT in a multi-band carrier aggregation system. As shown in FIG. 3, in the multi-band carrier aggregation system of this embodiment, there is only one TAT at the terminal. In such a case, if the timing advance command corresponding to only one certain band can cause TAT to be reset, the terminal can not grasp the uplink synchronization status of all the bands. For example, if the timing advance command corresponding to only band 0 can reset TAT, the terminal can not grasp the synchronization status of band 1. If all the timing advance commands corresponding to any one band can reset the TAT, the following situation may appear: receive multiple timing advance commands in one band at the time set by the timer At the same time, the other bands have not received the timing advance command but the timer is still running. According to the TAT principle, at the time set by the timer, the base station should be able to reasonably set the numerical value and the transmission timing in the timing advance command based on the uplink synchronization status, and maintain the operation of the timer. It is. If the terminal has not received the timing advance command at the set time, it recognizes that the uplink has lost synchronization. Therefore, in such a case, the uplink state obtained by the terminal from TAT is incorrect. For example, in FIG. 3, the numerical value set by TAT 0 is 500 ms. In this 500 ms, the terminal receives the timing advance command corresponding to band 1 twice but does not receive the timing advance command corresponding to band 0. At this time, although TAT is operating, the uplink of band 0 may actually lose synchronization.

  The following is a list of documents useful for understanding the present invention and the prior art, as incorporated by reference in the text and fully described in the text.

  [Non-patent document 1]: 3GPP TS 36.321 V10.1.0 (2011-3) Medium Access Control (MAC) protocol specification.

  The above-mentioned introduction to the background art is only for clearly and completely describing the technical solution of the present invention, and for the person skilled in the art to easily understand the present invention. The above technical solutions should not be considered as known to a person skilled in the art, as these solutions are stated in the background of the invention.

  An object of an embodiment of the present invention is to provide a method of maintaining a timing advance timer, a base station and a terminal. The process performed by the base station or terminal for the timing advance timer causes the timing advance timer corresponding to the band where the primary cell is located to last to expire and the timing advance timer corresponding to the band where the primary cell is located to have expired early. It is possible to avoid interruption of communication of the terminal.

According to an aspect of an embodiment of the present invention, there is provided a method of maintaining a timing advance timer TAT, said method applied to a base station, said method comprising
It is determined whether the band to perform uplink adjustment has only the band in which the primary cell is located; and if it includes only the band in which the primary cell is located, the timing advance command is sent to the band in which the primary cell is located. And transmitting and restarting a timing advance timer corresponding to the band where the primary cell is located.

According to another aspect of an embodiment of the present invention, a base station is provided, said base station comprising
A judgment unit for determining whether a band for uplink adjustment has only the band for the primary cell; and a band for uplink adjustment for the band for the primary cell When included, it includes a first transmission unit for transmitting a timing advance command to the band where the primary cell is located, and reactivating a timing advance timer corresponding to the band where the primary cell is located.

According to another aspect of an embodiment of the present invention, there is provided a method of maintaining a timing advance timer TAT, said method applied to a terminal, said method comprising
It is determined whether the broken TAT is the TAT corresponding to the band where the primary cell is located; and if the broken TAT is not the TAT corresponding to the band where the primary cell is present, it corresponds to the broken TAT. Clear the hybrid automatic retransmission request HARQ buffer in the band, and correspond to the dedicated resource corresponding to the carrier in the band corresponding to the broken TAT in the physical uplink control channel PUCCH and the carrier in the band corresponding to the broken TAT And releasing the measurement reference signal SRS.

According to another aspect of an embodiment of the present invention, a terminal device is provided, the terminal device comprising
A first determination unit for determining whether the expired TAT is a TAT corresponding to a band in which the primary cell is located; and a determination result of the first assessment unit is a band in which the expired TAT is located in the primary cell And clear the HARQ buffer in the band corresponding to the broken TAT, and dedicate the dedicated resource corresponding to the carrier in the band corresponding to the broken TAT in the PUCCH and the broken TAT. And a first processing unit for releasing an SRS corresponding to a carrier in a band corresponding to

  According to another aspect of an embodiment of the present invention, a computer readable program is provided, wherein said program is applied to a computer when executing said program at a base station, to said base station at said base station. Execute the timing advance timer maintenance method.

  According to another aspect of an embodiment of the present invention, there is provided a storage medium storing a computer readable program, wherein the computer readable program is applied to a computer, to a base station at the above mentioned base station at a base station. Run the advance timer maintenance method.

  According to another aspect of an embodiment of the present invention, a computer readable program is provided, wherein the program is applied to a computer when executing the program in a terminal device, and to the terminal device described above in the terminal device. Execute the timing advance timer maintenance method.

  According to another aspect of an embodiment of the present invention, there is provided a storage medium storing a computer readable program, wherein the computer readable program is applied to a computer, to a terminal device and to the above-mentioned terminal device in the terminal device. Run the advance timer maintenance method.

  The beneficial effect of the embodiment of the present invention is that the process performed by the base station or terminal for the timing advance timer causes the timing advance timer corresponding to the band where the primary cell is located to last to expire and the band where the primary cell is located. It is possible to avoid the interruption of the communication of the terminal due to the early expiration of the corresponding timing advance timer.

  With reference to the following description and the drawings, the specific embodiments of the present invention are disclosed in detail, and the manner in which the principles of the present invention may be adopted is clarified, but it should be understood that the embodiments of the present invention , On the range, not limited by them. Within the spirit and scope of the appended claims, embodiments of the present invention include all variations, modifications and alternatives.

  The features described and / or shown for one embodiment may be used in one or more other embodiments in the same or similar manner, in combination with the features in the other embodiments, or in other embodiments. Can replace the features of.

  Also, it should be emphasized that when used in the text, such words as "comprehensive (contains) / includes" refer to the presence of features, whole parts, steps or assemblies, but one or more other features, It does not exclude the presence or addition of whole parts, steps or assemblies.

Many aspects of the invention can be better understood with reference to the following drawings. The components in the drawings are not drawn to scale but merely to illustrate the principles of the present invention. Corresponding parts in the drawings may be enlarged or reduced to facilitate the illustration and explanation of parts of the present invention. The elements and features described in one drawing or one embodiment of the present invention can be combined with the elements and features illustrated in one or more other drawings or embodiments. Also, in the drawings, like numerals indicate corresponding parts in the several views, and can be used to indicate corresponding parts used in multiple embodiments.
5 is a flowchart of uplink synchronization processing of a base station and a terminal. FIG. 7 is a diagram showing a plurality of TATs in a multi-band carrier aggregation system. It is a figure which shows single TAT in the multi-band carrier aggregation system. It is a flowchart of the maintenance method of the timing advance timer by Example 1 of this invention. FIG. 7 is a diagram implicitly showing the format of the timing advance command of a band marker. FIG. 7 is a diagram explicitly showing the format of the timing advance command of a band marker. FIG. 10 is a diagram illustrating timing advance commands by aggregation of band indicators using BIT MAP. FIG. 7 is a diagram explicitly showing timing advance commands by aggregation of band indicators. It is a block diagram of the base station by Example 2 of this invention. It is a flowchart of the maintenance method of the timing advance timer by Example 3 of this invention. It is a block diagram of the terminal device by Example 4 of this invention. FIG. 1 shows a mobile telephone used as an example of a terminal according to an embodiment of the present invention.

  The above and other features of the embodiments of the present invention will become more apparent by the following description based on the drawings. These embodiments are illustrative only and are not intended to limit the present invention. In order for those skilled in the art to easily understand the principles and embodiments of the present invention, embodiments of the present invention will be described by taking the maintenance method of the timing advance timer in a multi-band carrier aggregation system as an example. It should be understood that embodiments of the present invention are not limited to the above-described system, but can be applied to other systems related to multiband.

  FIG. 4 is a flowchart of a method of maintaining a timing advance timer according to Embodiment 1 of the present invention. As shown in FIG. 4, the method includes the following steps.

Step 401: It is judged by the base station whether or not the band for which uplink adjustment is to be performed has only the band in which the primary cell is located; and Step 402: The judgment result of the base station is that “uplink adjustment is performed If the band to be tried includes only the band in which the primary cell is located, the base station transmits a timing advance command to the band in which the primary cell is located, and a timing advance timer corresponding to the band in which the primary cell is located. Restart the

  In the present embodiment, if the determination result of the base station is “including the band in which the band to be adjusted in uplink is not the band where the primary cell is located”, the base station executes the following steps. You may

  Step 403: The base station transmits a timing advance command to a band in which uplink adjustment is to be performed and a band in which the primary cell is located, and a timing advance timer corresponding to the band in which uplink adjustment is to be performed. And restart the timing advance timer corresponding to the band in which the primary cell is located.

  In this embodiment, even when the base station transmits the timing advance command, it is adopted to implicitly indicate the signaling format of the band requiring adjustment based on the different mechanism for transmitting the timing advance command. Well, it may be adopted to explicitly indicate the signaling format of the band that needs adjustment, or both may be adopted simultaneously. The following description is given by taking an example.

  When transmitting a corresponding timing advance command on a carrier in a band requiring adjustment, since the band requiring adjustment is a band carrying the timing advance command, identification information of this band can be expressed implicitly. In such a case, the timing advance command (Timing Advance Command) may not carry band identification information, and may adopt the format in Rel. 10 as shown in FIG.

  When a timing advance command corresponding to a certain band is transmitted to another band, it is necessary to carry band identification information, for example, a band index, to the timing advance command. Thus, a signaling format that explicitly indicates the band index, for example, the format in FIG. 6 may be adopted, and in such a case, in the signaling, the index of the band that needs adjustment is clearly indicated. There is a need.

  In this embodiment, the timing advance command may simultaneously use the signaling formats in FIG. 5 and FIG. 6, or may adopt the signaling format in FIG. 5 or FIG. The format depends on whether the band transmitting the timing advance command and the band corresponding to the command are the same band as described above.

  In this embodiment, since the timing advance command of the band where the PCell is located is always transmitted, the timing advance command of the band where the PCell is located may adopt the format of the timing advance command that represents the band indicator implicitly. . If the timing advance command of the band where PCell is located is not transmitted by the carrier of the band where PCell is located, whether the timing advance command corresponding to another band is transmitted on the carrier of that corresponding band or not. Instead, it is necessary to adopt the format of the timing advance command that explicitly represents the band indicator.

  Also, in the actual signaling transmission process, each timing advance command needs to be transmitted simultaneously with the subheader of one MAC layer, and this subheader mainly indicates the type of each command (in the MAC layer, In addition to timing advance commands, there are also many other types of commands), which allow the terminal to specify the specific meaning of each bit in different commands based on the type of command ( That is, the content of the command can be interpreted (understood). This subheader has a length of 1 byte, and when multiple timing advance commands are transmitted by one carrier, there are multiple subheaders, resulting in wasted resources. Therefore, a format may be employed in which multiple timing advance commands are aggregated and one subheader is shared. In this example, several options are provided as follows.

  1) As shown in FIG. 7, band markers are uniformly represented by Bitmap. Among them, when each bit corresponds to one band and the value of that bit is 1, it indicates that this message includes the timing advance command of the corresponding band; when the value of that bit is 0, This message indicates that the timing advance command of the corresponding band is not included. After the Bitmap, the timing advance commands corresponding to the bit being 1 are arranged in the order in the bitmap. Since the timing advance command of the band where the PCell is located is always transmitted, the band where the PCell is located may not have the corresponding bit in bitmap, and the corresponding timing advance command is placed at the position immediately after bitmap. As such, the timing advance command of the band corresponding to bit 1 in bitmap is immediately after the timing advance command of the PCell's local band.

  2) The band label is expressed in an explicit manner, but since the timing advance command of the band in which the PCell is present is always transmitted, as shown in FIG. 8, the label of the band in which the PCell is located may be omitted. Referring to FIG. 8, an extension for indicating whether the timing advance command TAC 0 of the band in which the PCell is located is at the front, and at the same time there is a timing advance command corresponding to another band at the same time. It has bit E0. For a band that has only SCells, an extension bit (for example, for indicating whether or not there is a timing advance command of another band at the same time, it is necessary to clearly indicate that band label (for example, Band Index 1). Requires E1). In the timing advance command by this kind of aggregation, if the number of timing advance commands reaches the maximum value according to a certain rule (for example, a certain terminal can only aggregate at most k bands), the last one One timing advance command TAC k does not require an extension bit.

  In one embodiment of the present example, all bands may correspond to one timing advance timer, ie, the terminal maintains one timing advance timer. In another embodiment of this example, each band may correspond to one timing advance timer, ie, the terminal maintains multiple timing advance timers, and each timing advance timer corresponds to one band. Do.

  In this embodiment, when the terminal maintains a plurality of timing advance timers, each timing advance timer may correspond to all carriers in one band, and corresponds to a part of carriers in one band. However, this embodiment is not limited to this.

  In this embodiment, it is recognized that the bands are one logical concept, and all carriers in the same band are the same if transmission characteristics are the same or carriers whose difference in transmission characteristics is smaller than a predetermined threshold. It is also good. That is, each band of the present embodiment corresponds to a plurality of carriers, and the transmission characteristics of the plurality of carriers here are the same, or the difference of the transmission characteristics of the plurality of carriers here is smaller than a predetermined threshold.

  According to the method of this embodiment, when the base station discovers that it is necessary to perform uplink adjustment of any one band other than the band where PCell is located, the band that needs adjustment and PCell Send a timing advance command to the existing band. When the base station discovers that it is necessary to perform uplink adjustment of only the band in which the PCell is located, it transmits a timing advance command only to the band in which the PCell is located. If the terminal has one TAT corresponding to each band according to the method of this embodiment, the TAT of the corresponding band is reset when the timing advance command is received, and the terminal has only one TAT. To have this only TAT reset when a timing advance command is received. This makes it possible to guarantee that the TAT corresponding to the band in which the PCell is located will last cut, and can solve the problems at the time of multiple TATs better. However, when there is only one TAT, the terminal may have a problem that all timing advance commands corresponding to any one band as shown in FIG. 3 can reset TAT. . However, since TAT is well reflected by the uplink status of the band where PCell is located, although TAT is working, there is no problem that the uplink of PCell's band has lost synchronization. . In such a case, if the base station determines that the terminal no longer needs a certain band having only SCells, it causes the terminal to release the resource of the band by the process of removing the arrangement for this band from the terminal. be able to.

  Embodiments of the present invention also provide a base station as described in Example 2 below. The principle by which the base station solves the problem is similar to the method for maintaining a timing advance timer based on the base station of the above-mentioned Embodiment 1, and the implementation of the base station can refer to the implementation of the above method, Here, duplicate explanations are omitted.

  FIG. 9 is a block diagram of a base station according to a second embodiment of the present invention. As shown in FIG. 9, the base station includes a determination unit 91 and a first transmission unit 92.

  Among them, the determination unit 91 is used to determine whether the band for which uplink adjustment is to be performed has only the band in which the primary cell is located.

  When the determination result of the determination unit 91 indicates that “the band for which uplink adjustment is to be performed includes only the band in which the primary cell is located”, the first transmission unit 92 sends a timing advance command to the band in which the primary cell is located. And is used to restart the timing advance timer corresponding to the band where the primary cell is located.

  In this embodiment, the base station may further include the following units:

  Second transmission unit 92: A band for performing uplink adjustment when the determination result of the determination unit 91 is “includes a band for which uplink adjustment is to be performed other than the band where the primary cell is located”. And, a timing advance command is sent to the band where the primary cell is located, and a timing advance timer corresponding to the band for which uplink adjustment is to be performed, and a timing avance timer corresponding to the band where the primary cell is restarted. Let

  The base station of this embodiment determines the transmission of the timing advance command by using the determination unit 91 to determine whether the band to be subjected to uplink adjustment has only the band in which the primary cell is located. Thus, at least it can be ensured that the timing advance command is transmitted to the band where the primary cell is located. As a result, regardless of whether the terminal maintains one timing advance timer or multiple timing advance timers, all uplink states of the band where the primary cell is located can be well reflected by TAT, so that the primary is not affected. It is possible to prevent an interruption of communication due to an early expiration of the timing advance timer corresponding to the band in which the cell is located.

  FIG. 10 is a flowchart of a method of maintaining a timing advance timer according to Embodiment 3 of the present invention. As shown in FIG. 10, the method includes the following steps.

Step 1001: The terminal determines whether the disconnected TAT is a TAT corresponding to the band where the primary cell is located; and Step 1002: if the disconnected TAT is not TAT corresponding to the band where the primary cell is located, The terminal clears the hybrid automatic retransmission request HARQ buffer in the band corresponding to the broken TAT, and the dedicated resource corresponding to the carrier in the band corresponding to the broken TAT in the physical uplink control channel PUCCH and the broken Release the measurement reference signal SRS corresponding to the carrier in the band corresponding to TAT.

  In this embodiment of this example, if the terminal determines that TAT corresponding to a band other than the band where PCell is located has expired, it recognizes that this is a normal operation, and clears only the HARQ buffer in this band. Release the dedicated resources corresponding to the carriers in this band in PUCCH and the SRS corresponding to the carriers in this band. Taking the situation shown in FIG. 2 again as an example, TAT 0 is TAT corresponding to the band where PCell is located, and TAT 1 and TAT 2 are TAT corresponding to the band where SCell is located. In some cases, the base station can determine that a certain terminal does not need a large number of bands anymore based on the determination of workload (service volume), and in this case, uplink synchronization in a certain band is intentionally lost. This allows resources to be released for other terminals. Therefore, a situation appears that TAT 0 is operating but TAT 1 or TAT 2 has expired, which is a kind of normal phenomenon.

  In this embodiment, since the broken TAT is not the TAT corresponding to the band in which the primary cell is located, the TAT corresponding to the band in which the primary cell is located is quickly ended, so that the corresponding resource is cleared or released. There is no problem with causing the link interruption.

  In another embodiment of the present embodiment, it is determined that the terminal judgment result is “the TAT which has been cut is the TAT which corresponds to the band where the primary cell is located, and the TAT which corresponds to the band where all the secondary cells are located”. For example, the terminal may perform the following steps.

  Step 1003: Clear HARQ buffers in all bands, release SRS corresponding to PUCCH and carriers in all bands, and clear any downlink assignments and uplink grants that have been placed.

  In this embodiment, if the terminal determines that the TAT corresponding to the band in which the PCell is located and the TAT corresponding to the bands in which all the other SCells are located have simultaneously expired, it clears the HARQ buffer in all bands, Release the SRS corresponding to the PUCCH and carriers in all bands and clear any downlink assignments and uplink grants placed. Thus, when the timer corresponding to the band in which the primary cell is located has expired, the timer corresponding to the band in which the secondary cell is located is also simultaneously ended, and clearing or releasing is simultaneously performed on the resource corresponding to the band in which the primary cell is located. And clear or release the resource corresponding to the band in which the secondary cell is located, and thus, the TAT corresponding to the band in which the primary cell is located is quickly exhausted, and the corresponding resource is cleared or released, and communication is performed. There is no problem with causing the link interruption.

  In another embodiment of this embodiment, the terminal may further perform the following steps if the determination result of the terminal is "the TAT which has been cut is the TAT corresponding to the band where the primary cell is located". .

Step 1004: The terminal determines whether the TAT corresponding to the band in which the secondary cell is located has been cut off; and Step 1005: If the TAT corresponding to the bands in which the secondary cell is located has already been cut, The terminal releases the HARQ buffer in the band in which the primary cell is located, releases the SRS corresponding to the PUCCH and the carrier in the band in which the primary cell is located, and any downlink assignments and uplink grants are placed. Clear

  In this embodiment, if the terminal determines that the TAT corresponding to the band in which the PCell is located has expired, but if the TAT corresponding to the bands in which all the non-PCells are located has already expired, the terminal may detect the location of the PCell. Release the HARQ buffer in the target band, release the SRS corresponding to the carrier in the band in which the PUCCH and PCell are located, and clear any downlink assignment and uplink grant that have been allocated. When the TAT corresponding to the band in which the primary cell is located has expired, if the TAT corresponding to the band in which the secondary cell is located has already expired, a clear or release operation is performed on the resource corresponding to the band in which the primary cell is located. The problem is that the secondary cell does not affect the band in which the secondary cell is located, which causes the corresponding resource to be cleared or released and causes the communication link to be interrupted by the TAT corresponding to the band in which the primary cell is broken. Does not occur.

  In the present embodiment, if the TAT corresponding to the band where all secondary cells are located has already been cut before this time, in other words, when the TAT corresponding to the band where the primary cell is located is still left, If there is a TAT corresponding to the band in which the secondary cell is operating, the terminal may perform processing in the manner of the next step 1006 or step 1007.

  Step 1006: The terminal releases the HARQ buffer in the band in which the primary cell is located, releases the SRS corresponding to the PUCCH and the carrier in the band in which the primary cell is located, and allocates any downlink assignments and Clear the uplink grant and also trigger the random access process.

  In this embodiment, the TAT corresponding to the band in which the PCell is located has expired, but if the TAT corresponding to the band in which the SCell is located is still operating, the terminal may use the HARQ buffer in the band in which the PCell is located. Release, release SRS corresponding to the carrier in the band where PUCCH and PCell are located, and clear any downlink assignments and uplink grants placed. After releasing the above resources, the terminal needs to perform uplink random access process immediately, regardless of whether there is new data of uplink / downlink being reached, which results in resources and uplink The TAT corresponding to the band where the PCell is located is also reset.

  Among them, the above-mentioned random access process may be initiated by a terminal or may be initiated by a base station. If initiated by the terminal, the terminal immediately initiates a random access process to the base station after releasing the above mentioned resources. The advantage of this type of scheme is that it is quick to respond, but because this type of random access is due to contention, it can cause a time delay or access failure when resources are scarce. is there. If originated by the base station, the base station can sound SRS corresponding to the carrier in the band where the primary cell is located, and when the SRS is empty, the resource of this part has already been released by the terminal. And acknowledge that the uplink where the primary cell is located has already lost synchronization, in which case the base station sends the terminal a command to instruct the terminal to perform random access. The advantage of this type of random access is that it is assignment-based and not contention-based, so the advantage is that the access success rate is high. However, the response is relatively slow, as the base station needs to sound the state of SRS.

  According to the method of step 1006, the terminal reacquires synchronization between the resource and the uplink by the random access process, thereby clearing the corresponding resource due to the TAT corresponding to the band where the primary cell is located being expired. Or there is no problem of releasing and causing interruption of communication link.

  Step 1007: The terminal stops TAT corresponding to the band in which the secondary cell is located, clears HARQ buffers in all bands, releases PUCCH and SRS corresponding to carriers in all bands, and arranges them. Clear any downlink assignments and uplink grants that have been made.

  In this embodiment, the TAT corresponding to the band in which the PCell is located has expired, but if the TAT corresponding to the band in which the SCell is located is still operating, the terminal further stops the active TAT. Simultaneously, clear the HARQ buffer in all bands, release the SRS corresponding to the PUCCH and the carriers in all bands, and clear any downlink assignments and uplink grants placed. May be

  According to the method of step 1007, the terminal stops the active TAT corresponding to the band in which the secondary cell is located, and thus the terminal is no longer able to transmit data with the band in which the secondary cell is located, so Since the TAT corresponding to the band in which the cell is located is cut, there is no problem in clearing or releasing the corresponding resource and affecting the band in which the secondary cell is located.

  In another embodiment of the present embodiment, if the disconnected TAT corresponds to the band in which the primary cell is located, the terminal may further perform the following steps.

Step 1008: Determine whether there is uplink data reached; and Step 1009: If there is uplink data reached, start a random access process.

  In this embodiment, when the terminal maintains a plurality of TATs, if there is uplink data reached, it is discovered that the TAT corresponding to the band in which the PCell is located has expired regardless of whether or not the other TATs have expired. Only if this is the case, the terminal initiates a random access process, acquires synchronization of resources and uplink, and simultaneously resets TAT.

  In this embodiment, even if the TAT corresponding to the band in which the primary cell is located has expired, when there is uplink data that has arrived, the terminal starts a random access process using the uplink data. Synchronization with the uplink can be acquired again, and TAT can be reset. Therefore, the TAT corresponding to the band in which the primary cell is located has not expired, and there is no problem of clearing or releasing the corresponding resource and causing a break in the communication link.

  In this embodiment, when the terminal maintains a plurality of timing advance timers, each timing advance timer may correspond to all carriers in one band, and corresponds to a part of carriers in one band. However, this embodiment is not limited to this.

  In the present embodiment, bands are a logical concept, and it may be recognized that all carriers have the same transmission characteristics, or carriers having a difference in transmission characteristics smaller than a predetermined threshold are all in the same band. That is, each band of the present embodiment corresponds to a plurality of carriers, and the transmission characteristics of a plurality of carriers here are the same, or the difference of the transmission characteristics of a plurality of carriers here is smaller than a predetermined threshold. .

  The above shows each step of the method of the present embodiment by the order number, but the present embodiment is not limited to the order before and after the execution of each step, and specifically, based on the result of the judgment, Determine the steps that need to be performed.

  According to the method of this embodiment, the terminal determines a specific processing method based on whether the disconnected TAT is the TAT corresponding to the band where the primary cell is located, and corresponds to the band where the primary cell is located. It can be guaranteed that the TAT last cut, which causes an impact on the band where the secondary cell is located when clearing or releasing the corresponding resource because the TAT corresponding to the band where the primary cell is located is quickly cut off. Since it is possible to prevent occurrence of communication interruption, it is possible to effectively solve the problem of maintaining one TAT or a plurality of TATs in a multi-band carrier aggregation wireless system.

  The embodiment of the present invention also provides a terminal device as described in the following fourth embodiment. The principle by which the terminal solves the problem is similar to the method for maintaining a timing advance timer based on the terminal according to the third embodiment described above, and the implementation of the terminal can refer to the implementation of the above method. Here, duplicate descriptions are omitted.

  FIG. 11 is a block diagram of a terminal according to a fourth embodiment of the present invention. As shown in FIG. 11, the terminal device includes a first determination unit 111 and a first processing unit 112.

  Among them, the first determination unit 111 is used to determine whether the broken TAT corresponds to the band in which the primary cell is located.

  The first processing unit 112 is in the band corresponding to the disconnected TAT when the determination result of the first determination unit 111 is “the disconnected TAT is a TAT corresponding to a band other than the band where the primary cell is located”. And clear the HARQ buffer and release the dedicated resource corresponding to the carrier in the band corresponding to the disconnected TAT in the PUCCH and the SRS corresponding to the carrier in the band corresponding to the disconnected TAT.

  In one embodiment, the terminal device further includes the following unit:

  Second processing unit 113: when the determination result of the first determination unit 111 is “the TAT corresponding to the band in which the primary cell is located is TAT and the TAT corresponding to the band in which all secondary cells are located”, It is used to clear HARQ buffers in all bands, release SRS corresponding to PUCCH and carriers in all bands, and clear any downlink assignments and uplink grants that have been placed.

  In one embodiment, the terminal device further includes the following unit:

  Second determination unit 114: Whether the TAT corresponding to the band in which the secondary cell is located is out when the determination result of the first determination unit 111 is “the TAT which is out corresponds to the band in which the primary cell is located”. It is used to determine whether or not.

  Third processing unit 115: HARQ in the band in which the primary cell is located, when the determination result of the second determination unit 114 is “all the TATs corresponding to the bands in which secondary cells are located have already been cut before this”. It is used to release the buffer, release the SRS corresponding to the carrier in the band in which the PUCCH and the primary cell are located, and clear any downlink assignments and uplink grants that have been placed.

  In one embodiment, the terminal device further includes the following unit:

  Fourth processing unit 116: Release the HARQ buffer in the band in which the primary cell is located, when the determination result of the second determination unit 114 indicates that “the TAT corresponding to the band in which the secondary cell is located is present”. , And release SRS corresponding to the carrier in the band where the PUCCH and the primary cell are located, and used to clear any downlink assignment and uplink grant that have been placed.

  First access unit 117: used to initiate a random access process after the processing of the fourth processing unit 116 is completed.

  In one embodiment, the terminal device further includes the following unit:

  Fifth processing unit 118: stopping the TAT corresponding to the band where the secondary cell is present, when the judgment result of the second judgment unit 114 indicates that "the TAT corresponding to the band where the secondary cell is operating is present". It is used to clear HARQ buffers in all bands, release SRS corresponding to PUCCH and carriers in all bands, and clear any downlink assignments and uplink grants placed.

  In one embodiment, the terminal device further includes the following unit:

  Third determination unit 119: When the determination result of the first determination unit 111 is “the TAT which has been cut is a TAT corresponding to the band where the primary cell is located”, it is determined whether or not there is uplink data reached. Used for

  Second access unit 1110: Used to initiate a random access process when the determination result of the third determination unit 119 is "there is uplink data reached".

  The terminal apparatus of this embodiment determines a specific processing method based on whether or not the disconnected TAT is the TAT corresponding to the band where the primary cell is located, and the TAT corresponding to the band where the primary cell is located is It guarantees that it has been disconnected last, so that the TAT corresponding to the band in which the primary cell is located is early terminated, affecting the band in which the secondary cell is located when clearing or releasing the corresponding resource. In the multi-band carrier aggregation wireless system, the problem of maintaining one TAT or TATs can be effectively solved.

  FIG. 12 shows a mobile telephone used as an example of a terminal according to an embodiment of the present invention. Examples of terminal devices are not limited to mobile phones. The terminal device may be any device having communication capability, such as a game console, a PDA, a notebook PC, etc. As shown in FIG. 12, the mobile telephone 10 may be a foldable telephone having a cover 15 movable between an open position and a closed position. In FIG. 12, the cover 15 is in the open position. It should be understood that the mobile telephone 10 may have other structures, for example, a "long board telephone" or a "sliding telephone" structure.

  Mobile telephone 10 may have a display 14. The display 14 displays, for example, information such as operation status, time, telephone number, telephone directory information, various menus for the user, whereby the user utilizes various features of the mobile telephone 10 Can. The display 14 may further be used to visibly display content received by the mobile telephone 10 and / or retrieved from a storage (not shown) of the mobile telephone 10. The display 14 may further be used to display images, videos and other graphics, such as photos, mobile television content, and videos associated with games, for the user.

  The keyboard 18 is for providing a plurality of types of user input operations. For example, the keyboard 18 may include syllabary and numeric keys that allow the input of alphabetic and numeric information (e.g., telephone numbers, phone lists, phonebook information, notepads, text, etc.). The keyboard 18 may also include certain function keys 17, for example, a "outgoing" key to make or answer a call, and an "end" key to end the call or hang up. The specific function keys may further include a menu navigation key and a selection key for performing navigation in the menu displayed on the display 14. For example, by providing a pointing device and / or a navigation key, directional input from the user is received. The display 14 and the keyboard 18 can also be combined with each other to realize the function of the soft key. The mobile telephone 10 may further include components necessary to realize other functions such as an antenna, a microcontroller, a speaker 50, and a microphone 52.

  The embodiment of the present invention further provides a computer readable program, wherein when executing the program at the base station, the program causes the computer to execute the timing advance timer described in the first embodiment at the base station. Run the maintenance method.

  The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes the computer to maintain the timing advance timer described in the first embodiment at the base station. Run

  The embodiment of the present invention further provides a computer readable program, wherein when executing the program in the terminal device, the program causes the computer to execute the timing advance timer described in the third embodiment in the terminal device. Run the maintenance method.

  The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes the computer to maintain the timing advance timer described in the third embodiment in the terminal device. Run

  The above apparatus and method of the present invention may be realized by hardware or may be realized by a combination of hardware and software. The invention also relates to such a computer readable program, which, when executed by the logic component, can cause the logic component to execute the device or component described above, or the logic component Can perform the various methods or steps described above. The present invention further relates to a recording medium recording the above-mentioned program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory and the like.

  Although the present invention has been described above based on the specific embodiments, it should be understood by those skilled in the art that these descriptions are only exemplary and do not limit the protection scope of the present invention. . Those skilled in the art may make all variations and modifications to the present invention based on the spirit and principle of the present invention, and these variations and modifications are also within the technical scope of the present invention.

Claims (2)

A terminal apparatus maintaining a timer related to uplink synchronization in a carrier aggregation system, comprising:
A timer associated with the band corresponding to the primary cell, wherein the first timer for uplink synchronization has expired, and a timer associated with the band corresponding to the secondary cell, the second timer for uplink synchronization Clear all hybrid automatic repeat request (HARQ) buffers in all bands corresponding to the primary cell and the secondary cell, and in all bands corresponding to the primary cell and the secondary cell. A terminal apparatus comprising control means for releasing a physical uplink control channel (PUCCH) corresponding to a carrier and a measurement reference signal (SRS) and clearing all downlink assignments and uplink grants set. The terminal device according to claim 1, wherein
The terminal device further stops the operation of the timer associated with the band corresponding to the secondary cell, when the first timer has expired and the second timer has been activated. .

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