Background technology
One, RRC (Radio Resource Control, Radio Resource control) connection release message and cell selecting brief introduction.
Comprise redirection information and cell reselection priority information in the RRC connection release message.Redirection information is used for specifying a specific frequency to UE (User Equipment, subscriber equipment), after UE discharges the RRC connection, preferentially carries out cell selecting on this frequency.And cell reselection priority information is used for can carrying out the priority of the frequency of sub-district gravity treatment after the UE indicating cell is selected.
Network sends dedicated signaling to UE and discharges connection, UE enters RRC_IDLE (RRC_ idle pulley) state and resides in a certain sub-district through cell selecting (cell selection) from RRC_CONNECTED (RRC_ connection mode) state, UE should attempt residing in last sub-district (implicit expression of RRC_CONNECTED state, when being redirected) or E-UTRAN (Evolved UMTS Terrestrial Radio Access Network, the UMTS Terrestrial radio access network of evolution of in the dedicated signaling of state exchange, indicating; UMTS:Universal Mobile Telecommunication System, universal mobile telecommunications system) sub-district (explicit, as to pass through redirection information) in frequency or other RAT (Radio Access Technology, the wireless access technology) frequency; When residing in a certain sub-district, UE during triggering cell gravity treatment flow process, should attempt gravity treatment to a proper cell (suitable cell).Fig. 1 is idle pulley (RRC_IDLE) cell selecting and gravity treatment implementing procedure schematic diagram, does not have proper cell (suitable cell) in the time of can selecting at UE, and the flow process shown in the dotted line of overstriking among Fig. 1 so is divided into three kinds of situations substantially:
If a) this UE enters connection status from " normally resident " state (camped normally), when it gets back to idle condition so, if the frequency of indicating in dedicated signaling (explicit or implicit expression) does not have proper cell (suitable cell) to select, UE should carry out the cell selecting flow process by the cell information (stored information) of storage and select a proper cell (suitable cell) resident; If can not obtain proper cell in the cell information of storage, enter cell initial search flow process (initial cell selection) so.
B) if this UE enters connection status from " residing in any sub-district " state (camped on any cell), when it gets back to Idle state so, if the frequency of indicating in dedicated signaling (explicit or implicit expression) does not have acceptable sub-district (acceptable cell) to select, UE should enter " any cell selecting " state (any cell selection), continuation acceptable sub-district of search (acceptable cell) in all PLMN (Public Land MobileNetwork, public land mobile network) is carried out resident.
C) but can not choose proper cell (suitable cell) if triggered the sub-district gravity treatment at " normally resident " state (camped normally), perhaps triggered the sub-district gravity treatment and but can not choose acceptable sub-district (acceptable cell) at " residing in any sub-district " state (camped onany cell), UE can enter " any cell selecting " state (any cell selection), and the acceptable sub-district of search (acceptable cell) is carried out resident in all PLMN that UE supports.
Two, based on the different frequency/different technique district gravity treatment brief introduction of priority.
Alien frequencies and different technique district gravity treatment are all judged based on priority and are carried out.UE is when carrying out reselection evaluation to certain different frequency/different technology, need distinguish according to the relation (be higher than, equal, be lower than) of its priority and the resident frequency priority of current UE and treat, detail is seen 5.2.4.5 joint among 3GPP (the 3rd Generation Partnership Project) 36.304.
In addition, when UE judges whether that startup is measured certain different frequency/different technology, also to distinguish and treat according to the relation of its priority and the resident frequency of current UE:
A), be higher than the different frequency/different technology of the resident frequency of current UE, measure according to the requirement of 3GPP (3rdGeneraion Partnership Project) 36.133 agreements for priority;
B), be equal to or less than the different frequency/different technology of the resident frequency of current UE for priority, when the Serving cell quality is lower than certain thresholding (S
Nonintrasearch) time, just start corresponding measurement.
Three, the indicatory device brief introduction of priority.
Between different different technology, do not allow identical priority.And current agreement regulation UE can only provide by system information E-UTRAN frequency or different technology frequency and hereto frequency the assessment of just carrying out the sub-district gravity treatment under the situation of priority is arranged.
The frequency precedence information of sub-district gravity treatment is from following two kinds of means:
A), common signaling (being system information): wherein provide the precedence information of the resident frequency of current UE, the precedence information separately of other frequencies of E-UTRAN, and the precedence information separately of each frequency (section) of other RAT.This is called public precedence information.
B), dedicated signaling: in the RRC connection release message, carry the priority list of E-UTRAN different frequency/different technology frequency alternatively, and corresponding term of validity timer length.This is called special priority information.In dedicated signaling, also carried simultaneously dedicated priority timer effective time T320.
Four, public precedence information and special priority information concerns brief introduction.
Stipulate that in existing LTE (Long Term Evolution, Long Term Evolution) standard when UE did not receive dedicated signaling indication special priority information, the public priority that provides in the using system information was measured and the sub-district gravity treatment; After receiving special priority information, UE will no longer consider any public precedence information, behind the term of validity timer expiry or (because other reasons) termination of special priority information, UE just can abandon special priority information, and restarts to carry out corresponding measurement and sub-district gravity treatment based on public precedence information.
The deficiencies in the prior art are: under some scene, dedicated cell gravity treatment priority and special-purpose timer are effective, and UE can not reside in the sub-district that these have dedicated cell gravity treatment priority, resident sub-district was not the sub-district under (the explicit or implicit expression) frequency of indicating in the connection release message after for example the UE connection discharged, sub-district under the frequency of cell reselection priority is provided in neither connection release message, and connection release message provides the cell reselection priority of other frequencies, and this situation causes this UE can't carry out the measurement and the reuse adoption process of any different frequency/different technology before the dedicated priority timer expiry.
Summary of the invention
The invention provides a kind of definite method and apparatus of cell reselection priority,, can't proceed to the problem of different frequency/different technique district gravity treatment owing to there is not efficient cell gravity treatment precedence information in order to what exist in the solution prior art.
A kind of definite method of cell reselection priority is provided in the embodiment of the invention, has comprised the steps:
Whether the dedicated cell gravity treatment priority timer of judging UE is overtime;
Judge whether UE is resident to the frequency that does not have the configure dedicated cell reselection priority;
Before dedicated cell gravity treatment priority timer expiry, UE is resident when not having the frequency of configure dedicated cell reselection priority, determines the cell reselection priority that UE uses.
Preferably, the cell reselection priority that described definite UE uses comprises:
Determine that subscriber equipment uses default fixedly dedicated cell gravity treatment priority at its resident frequency to this frequency.
Preferably, described default fixedly dedicated cell gravity treatment priority limit is greater than the subscriber equipment cell reselection priority scope of the explicit dispensing of all high-level signalings.
Preferably, the cell reselection priority that described definite subscriber equipment uses comprises:
Determine the cell reselection priority of this frequency that subscriber equipment provides in its resident frequency using system information.
Preferably, the cell reselection priority that described definite subscriber equipment uses comprises:
Determine that cell reselection priority that subscriber equipment uses at its resident frequency is the public priority in the public precedence information.
Preferably, described public precedence information is the public precedence information that is provided by system information.
Preferably, when UE uses public priority, further comprise:
Delete cell reselection priority and dedicated priority timer that all are provided by dedicated signaling.
A kind of subscriber equipment also is provided in the embodiment of the invention, has comprised:
Overtime judge module is used to judge whether the dedicated cell gravity treatment priority timer of UE is overtime;
The priority judge module is used to judge whether UE is resident to the frequency that does not have the configure dedicated cell reselection priority;
The priority determination module was used for before dedicated cell gravity treatment priority timer expiry, and UE is resident when not having the frequency of configure dedicated cell reselection priority, determined the cell reselection priority that UE uses.
Preferably, described priority determination module comprises: one of first priority unit, second priority unit, the 3rd priority unit or its combination:
First priority unit is used to determine at its resident frequency this frequency to be used default fixedly dedicated cell gravity treatment priority;
Second priority unit is used for determining the cell reselection priority of this frequency that UE provides in its resident frequency using system information;
The 3rd priority unit is used for determining cell reselection priority that UE uses at its resident frequency public precedence information as system information.
Preferably, described first priority unit is further used for the subscriber equipment cell reselection priority scope of default fixedly dedicated cell gravity treatment priority limit greater than the explicit dispensing of all high-level signalings of using.
Preferably, described the 3rd priority unit is further used for obtaining public precedence information from system information.
Preferably, described the 3rd priority unit further comprises:
The deletion subelement is used for deleting cell reselection priority and dedicated priority timer that all are provided by dedicated signaling when using public priority.
Beneficial effect of the present invention is as follows:
In the invention process, judge at first whether the dedicated cell gravity treatment priority timer of UE is overtime, and whether UE is resident to the frequency that does not have the configure dedicated cell reselection priority; When before dedicated cell gravity treatment priority timer expiry, UE is resident when not having the frequency of configure dedicated cell reselection priority, just determine the cell reselection priority that UE uses, solved in the prior art before dedicated cell gravity treatment priority timer expiry, UE is resident when not having the frequency of configure dedicated cell reselection priority, can't proceed to the problem of different frequency/different technique district gravity treatment owing to there is not efficient cell gravity treatment precedence information, guaranteed that UE under any circumstance can proceed to the sub-district gravity treatment of alien frequencies or different technology, guaranteed the smooth implementation of subscriber equipment, strengthened sense of experience of users degree of being subjected in follow-up resident and call setup flow process.
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described.
The inventor notices in the invention process, under some scene, dedicated cell gravity treatment priority and special-purpose timer are effective, and UE can not reside in the sub-district that these have dedicated cell gravity treatment priority, resident sub-district was not the sub-district under (the explicit or implicit expression) frequency of indicating in the connection release message after for example the UE connection discharged, sub-district under the frequency of cell reselection priority is provided in neither connection release message, and connection release message provides the cell reselection priority of other frequencies, and this situation causes this UE can't carry out the measurement and the reuse adoption process of any different frequency/different technology before the dedicated priority timer expiry.
Fig. 2 provides available frequency point information schematic diagram after the frequency priority for dedicated signaling, P represents the priority under this frequency among the figure, the typical scene that then can't carry out the measurement of any different frequency/different technology and reuse adoption process as shown in Figure 2, the connection release message that UE receives has been indicated f2, the special priority information of f3 and dedicated cell gravity treatment priority timer, the system information of the frequency f1 that the UE of dedicated signaling indication simultaneously is preferential resident provides f1, f2, the public precedence information of three frequencies of f3, but the condition of proper cell (suitable cell) all can not be satisfied in the sub-district among the f1, so UE is resident to frequency f4 sub-district down, the sub-district frequency f4 under may be by storing proper cell (suitable cell) that cell information (stored information) or initial cell selection (initial cellselection) obtains or the acceptable cell (acceptable cell) that obtains by " any cell selecting " state (any cell selection state).
According to existing protocol, UE is after receiving connection release message, because frequency f1 does not satisfy resident condition, UE is resident to frequency f4, but UE only has the dedicated priority of f2, two frequencies of f3, and the current resident frequency f4 of UE is without any cell reselection priority information.
Under another typical scene, before dedicated cell gravity treatment priority timer expiry, if having triggered the sub-district gravity treatment at " normally resident " state (camped normally), UE but can not choose proper cell (suitable cell), perhaps triggered the sub-district gravity treatment and but can not choose acceptable sub-district (acceptable cell) at " residing in any sub-district " state (camped on any cell), can enter " any cell selecting " state (any cell selection), continue in all PLMN, to search for acceptable sub-district (acceptable cell) and carry out resident.The resident dedicated cell gravity treatment precedence information that can not guarantee to have current resident frequency behind the new sub-district of UE under these situations.
According to the description of front as can be known, in case UE can't determine the precedence information of current resident frequency, it also can't normally carry out the measurement and the reuse adoption process of other any different frequency/different technology so, and then influences follow-up resident and call setup flow process, thereby has worsened user experience.
Based on this, proposed in the invention process before dedicated cell gravity treatment priority timer expiry, when UE resides in the frequency that does not have the configure dedicated cell reselection priority, determine that the cell reselection priority that UE uses solves this problem.
Fig. 3 is definite method implementing procedure schematic diagram of cell reselection priority, as shown in the figure, carrying out cell reselection priority when determining, can comprise the steps:
Step 301, judge whether the dedicated cell gravity treatment priority timer of UE is overtime;
Step 302, judge whether UE is resident to the frequency that does not have the configure dedicated cell reselection priority;
Step 303, before dedicated cell gravity treatment priority timer expiry, UE is resident when not having the frequency of configure dedicated cell reselection priority, determines the cell reselection priority that UE uses.
In the enforcement, step 301 and the uninevitable execution sequential relationship of step 302, it all is the necessary condition of execution in step 303, need only satisfy getting final product.
Below the execution mode of determining the cell reselection priority that UE uses in the step 303 is described.Consider the producing method that priority is possible, clearly decide the execution mode of the cell reselection priority of UE use below the priority that fixedly installs from frequency respectively, the priority of from system information, obtaining and the priority from public precedence information.Obviously, by the description of following execution mode as can be seen, as long as can guarantee UE the cell reselection priority information of resident frequency is arranged on its resident frequency, guarantee that the execution mode that UE under any circumstance can proceed to the sub-district gravity treatment of alien frequencies or different technology can realize the present invention.
One, determines that UE uses default fixedly dedicated cell gravity treatment priority at its resident frequency to this frequency.
In the enforcement, before dedicated cell gravity treatment priority timer expiry, when UE resides in the frequency that does not have the configure dedicated cell reselection priority, this frequency uses fixing cell reselection priority information, to guarantee that UE can have the special priority information of resident frequency all the time, so that the carrying out of follow-up measurement and cell reselection process.
Fig. 4 is for using fixing dedicated cell gravity treatment precedence information schematic diagram, and P represents the priority under this frequency among the figure, and then as shown in the figure, when having indicated dedicated cell gravity treatment priority and timer to be example in connection release message, concrete enforcement can be as follows:
The preferential resident frequency of the UE of connection release message indication is f1, and the public precedence information of some frequency f1, f2 is provided in this system information of subdistricts, has indicated the special priority information P of (at least one) frequency (for example f2 frequency) in the connection release message
F2 *UE does not have proper cell (suitablecell) can be resident the time at frequency f1, selection resides in a certain sub-district under the frequency f3, the public precedence information of some frequency f2, f3 is provided in this system information of subdistricts, and then UE resides in that available dedicated priority is the priority P of f2 behind the frequency f3
F2 *The priority P of (from dedicated signaling), f3
f *(from fixed value) can proceed to alien frequencies or different technique district gravity treatment to guarantee this UE that resides in f3 before the dedicated priority timer expiry.
In concrete the enforcement, the fixedly dedicated cell gravity treatment precedence information of presetting in UE can be set to the UE cell reselection priority scope greater than the explicit dispensing of all high-level signalings.
For example: the UE cell reselection priority scope of the explicit dispensing of all high-level signalings generally is made as 8 grades in the prior art, it is the 0-7 level, default fixed priority scope is greater than the UE cell reselection priority scope of the explicit dispensing of all high-level signalings, that is to say and refer to that this scope is greater than 0-7, both can be less than lowest priority 0, also can certainly in 0-7, select greater than limit priority 7.Adopt the purpose of this mode to be to make the cell reselection process of UE side more flexible.The reason that this mode can be implemented only needs UE to discern and get final product after being that this scope is set, and does not relate to network side because this reuse adoption process also only relates to UE, so need not network improved and just can realize UE is indicated more flexibly.
Two, determine the cell reselection priority of this frequency that UE provides in its resident frequency using system information.
In the enforcement, before dedicated cell gravity treatment priority timer expiry, when UE resides in the frequency that does not have the configure dedicated cell reselection priority, this frequency is provided by the cell reselection priority information of this frequency that provides in the current persistent district system information of UE, to guarantee that UE can have the special priority information of resident frequency all the time, so that the carrying out of follow-up measurement and cell reselection process.
The cell reselection priority information schematic diagram that Fig. 5 provides for using system information, P represents the priority under this frequency among the figure, then as shown in the figure, when having indicated dedicated cell gravity treatment priority and timer to be example in connection release message, concrete enforcement can be as follows:
The preferential resident frequency of the UE of connection release message indication is f1, the public precedence information of some frequency f1, f2, f3 is provided in this system information of subdistricts, has indicated the special priority information P of (at least one) frequency (for example f2 frequency) in the connection release message
F2 *UE does not have the proper cell (suitable cell) can be resident at frequency f1, selection resides in a certain sub-district under the frequency f3, the public precedence information of some frequency f2, f3, f4 is provided in this system information of subdistricts, and then UE resides in that available dedicated priority is the priority P of f2 behind the frequency f3
F2 *The priority P of (from dedicated signaling), f3
F3(from the system information of UE persistent district) can proceed to alien frequencies or different technique district gravity treatment to guarantee this UE that resides in f3 before the dedicated priority timer expiry:
Three, determine that UE when the cell reselection priority that its resident frequency uses, uses the public priority in the public precedence information all.
In the enforcement, public precedence information can be the public precedence information that is provided by system information.
When using public priority all, can further include:
Delete cell reselection priority and dedicated priority timer that all are provided by dedicated signaling.
In the enforcement, before dedicated cell gravity treatment priority timer expiry, when UE resides in the frequency that does not have the configure dedicated cell reselection priority, delete all dedicated cell gravity treatment priority and timers, the public precedence information that provides by system information all is provided, to guarantee that UE can have the precedence information of resident frequency all the time, so that the carrying out of follow-up measurement and cell reselection process describes with example below.
Embodiment (1):
Fig. 6 for the sub-district gravity treatment after whole common cell gravity treatment precedence information embodiment (1) schematic diagrames of providing of using system information, P represents the priority under this frequency among the figure, then as shown in the figure, it is prerequisite when being example that at least one cell reselection priority is provided in connection release message, and concrete enforcement can be as follows:
The preferential resident frequency of the UE of connection release message indication is f1, the public precedence information of some frequency f1, f2, f3 is provided in this system information of subdistricts, has indicated the special priority information P of (at least one) frequency (for example f3 frequency) in the connection release message
F3 *UE does not have the proper cell (suitable cell) can be resident at frequency f1, selection resides in a certain sub-district under the frequency f4, and the public precedence information of some frequency f3, f4, f5 is provided in this system information of subdistricts, then deletes precedence information that whole dedicated signalings provide (as P
F3 *) and dedicated priority timer, UE resides in that available priority is P behind the frequency f4
F3, P
F4, P
F5(all from system information) can proceed to alien frequencies or different technique district gravity treatment to guarantee this UE that resides in f4.
Embodiment (2):
Fig. 7 for the sub-district gravity treatment after whole common cell gravity treatment precedence information embodiment (2) schematic diagrames of providing of using system information, P represents the priority under this frequency among the figure, then as shown in the figure, before with dedicated cell gravity treatment priority timer expiry, the gravity treatment of UE sub-district is to frequency that does not have dedicated cell gravity treatment priority when being example, and concrete enforcement can be as follows:
The sub-district of UE " normally resident " (camped normally) under frequency f1, dedicated cell gravity treatment priority timer moves simultaneously, and the gravity treatment of UE triggering cell is less than choosing proper cell (suitable cell) under the frequency that frequency priority is provided at dedicated signaling; Perhaps UE " resides in any sub-district " at frequency f1 (camped on any cell), dedicated cell gravity treatment priority timer moves simultaneously, and the gravity treatment of UE triggering cell is less than choosing acceptable sub-district (acceptable cell) under the frequency that frequency priority is provided at dedicated signaling; UE should enter " any cell selecting " (any cell selection), select the acceptable cell (acceptable cell) under the frequency f2 to carry out resident, the public precedence information of some frequency f2, f3, f4 is provided in this system information of subdistricts, and whole precedence informations that provided by dedicated signaling of then deleting the UE storage are (as comprising P
F1 *, P
F3 *) and dedicated priority timer, UE resides in that available priority is P behind the frequency f2
F2, P
F3, P
F4(all from system information) can proceed to alien frequencies or different technique district gravity treatment to guarantee this UE that resides in f2.
By above-mentioned execution mode as can be seen, as long as before dedicated cell gravity treatment priority timer expiry, when UE resides in the frequency that does not have the configure dedicated cell reselection priority, can guarantee that UE has the cell reselection priority information of resident frequency on its resident frequency, guarantee that the execution mode that UE under any circumstance can proceed to the sub-district gravity treatment of alien frequencies or different technology can realize the present invention, can solve and normally to carry out the measurement of other any different frequency/different technology and the problem of reuse adoption process, guaranteed the smooth implementation of subscriber equipment, strengthened sense of experience of users degree of being subjected in follow-up resident and call setup flow process.
Based on same inventive concept, a kind of subscriber equipment also is provided in the embodiment of the invention, because the principle that these equipment are dealt with problems is similar to definite method of cell reselection priority, so the enforcement of these equipment can repeat part and not give unnecessary details referring to the enforcement of method.
Fig. 8 is the user device architecture schematic diagram, and the UE in the enforcement can determine cell reselection priority, as shown in the figure, can comprise among the UE:
Overtime judge module 801 is used to judge whether the dedicated cell gravity treatment priority timer of UE is overtime;
Priority judge module 802 is used to judge whether UE is resident to the frequency that does not have the configure dedicated cell reselection priority;
Priority determination module 803 was used for before dedicated cell gravity treatment priority timer expiry, and UE is resident when not having the frequency of configure dedicated cell reselection priority, determined the cell reselection priority that UE uses.
In the enforcement, can comprise in the priority determination module: one of first priority unit, second priority unit, the 3rd priority unit or its combination:
First priority unit is used for determining that UE uses default fixedly dedicated cell gravity treatment priority at its resident frequency to this frequency;
Second priority unit is used for determining the cell reselection priority of this frequency that UE provides in its resident frequency using system information;
The 3rd priority unit is used for determining cell reselection priority that UE uses at its resident frequency public precedence information as system information.
In the enforcement, first priority unit can also be further used for the subscriber equipment cell reselection priority scope of default fixedly dedicated cell gravity treatment priority limit greater than the explicit dispensing of all high-level signalings of using.
In the enforcement, the 3rd priority unit can also be further used for obtaining public precedence information from system information.
The 3rd priority unit may further include:
The deletion subelement is used for deleting cell reselection priority and dedicated priority timer that all are provided by dedicated signaling when using public priority.
By the foregoing description as can be known, definite scheme of cell reselection priority has been proposed in the invention process, solved in the prior art before dedicated cell gravity treatment priority timer expiry, UE is resident when not having the frequency of configure dedicated cell reselection priority, can't proceed to the problem of different frequency/different technique district gravity treatment owing to there is not efficient cell gravity treatment precedence information.
Those skilled in the art should understand that embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt complete hardware embodiment, complete software implementation example or in conjunction with the form of the embodiment of software and hardware aspect.And the present invention can adopt the form that goes up the computer program of implementing in one or more computer-usable storage medium (including but not limited to magnetic disc store, CD-ROM, optical memory etc.) that wherein include computer usable program code.
The present invention is that reference is described according to the flow chart and/or the block diagram of method, equipment (system) and the computer program of the embodiment of the invention.Should understand can be by the flow process in each flow process in computer program instructions realization flow figure and/or the block diagram and/or square frame and flow chart and/or the block diagram and/or the combination of square frame.Can provide these computer program instructions to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, make the instruction of carrying out by the processor of computer or other programmable data processing device produce to be used for the device of the function that is implemented in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame appointments.
These computer program instructions also can be stored in energy vectoring computer or the computer-readable memory of other programmable data processing device with ad hoc fashion work, make the instruction that is stored in this computer-readable memory produce the manufacture that comprises command device, this command device is implemented in the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.
These computer program instructions also can be loaded on computer or other programmable data processing device, make on computer or other programmable devices and to carry out the sequence of operations step producing computer implemented processing, thereby the instruction of carrying out on computer or other programmable devices is provided for being implemented in the step of the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.
Although described the preferred embodiments of the present invention, in a single day those skilled in the art get the basic creative notion of cicada, then can make other change and modification to these embodiment.So claims are intended to all changes and the modification that are interpreted as comprising preferred embodiment and fall into the scope of the invention.
Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.