Patent Publication Number: US-9838972-B2

Title: Method for controlling power of uplink channel, user equipment and communication system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of International Application PCT/CN2014/077055 filed on May 8, 2014, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the field of communications, and in particular to a method for controlling power of an uplink channel, a user equipment (UE) and a communication system. 
     BACKGROUND 
     In a long-term evolution (LTE) system, methods for controlling power in transmitting a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), an uplink sounding reference signal (SRS) and a physical random access channel (PRACH) by a UE are defined. When the UE is configured with multiple carriers, independent power control of uplink transmission signal is performed in each serving cell; 
     when the PUSCH and the PUCCH cannot be transmitted at the same time, a power control formula of the PUSCH is: 
     
       
         
           
             
               
                 
                   
                     
                       
                         P 
                         
                           PUSCH 
                           , 
                           c 
                         
                       
                       ⁡ 
                       
                         ( 
                         i 
                         ) 
                       
                     
                     = 
                     
                         
                     
                     ⁢ 
                     
                       min 
                       ⁢ 
                       
                         
                           { 
                           
                             
                               
                                 
                                   
                                     
                                       P 
                                       
                                         CMAX 
                                         , 
                                         c 
                                       
                                     
                                     ⁡ 
                                     
                                       ( 
                                       i 
                                       ) 
                                     
                                   
                                   , 
                                 
                               
                             
                             
                               
                                 
                                   
                                     
                                       
                                         
                                           10 
                                           ⁢ 
                                           
                                             
                                               log 
                                               10 
                                             
                                             ⁡ 
                                             
                                               ( 
                                               
                                                 
                                                   M 
                                                   
                                                     PUSCH 
                                                     , 
                                                     c 
                                                   
                                                 
                                                 ⁡ 
                                                 
                                                   ( 
                                                   i 
                                                   ) 
                                                 
                                               
                                               ) 
                                             
                                           
                                         
                                         + 
                                         
                                           
                                             P 
                                             
                                               
                                                 O 
                                                 ⁢ 
                                                 _ 
                                                 ⁢ 
                                                 PUSCH 
                                               
                                               , 
                                               c 
                                             
                                           
                                           ⁡ 
                                           
                                             ( 
                                             j 
                                             ) 
                                           
                                         
                                         + 
                                       
                                     
                                   
                                   
                                     
                                       
                                         
                                           
                                             
                                               α 
                                               c 
                                             
                                             ⁡ 
                                             
                                               ( 
                                               j 
                                               ) 
                                             
                                           
                                           · 
                                           
                                             PL 
                                             c 
                                           
                                         
                                         + 
                                         
                                           
                                             Δ 
                                             
                                               TF 
                                               , 
                                               c 
                                             
                                           
                                           ⁡ 
                                           
                                             ( 
                                             i 
                                             ) 
                                           
                                         
                                         + 
                                         
                                           
                                             f 
                                             c 
                                           
                                           ⁡ 
                                           
                                             ( 
                                             i 
                                             ) 
                                           
                                         
                                       
                                     
                                   
                                 
                               
                             
                           
                           } 
                         
                         ⁢ 
                         
                             
                         
                         [ 
                         dBm 
                         ] 
                       
                     
                   
                   ; 
                 
               
               
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
     
     and when the PUSCH and the PUCCH can be transmitted at the same time, the power control formula of the PUSCH is: 
     
       
         
           
             
               
                 
                   
                     
                       
                         P 
                         
                           PUSCH 
                           , 
                           c 
                         
                       
                       ⁡ 
                       
                         ( 
                         i 
                         ) 
                       
                     
                     = 
                     
                         
                     
                     ⁢ 
                     
                       min 
                       ⁢ 
                       
                         
                           { 
                           
                             
                               
                                 
                                   
                                     10 
                                     ⁢ 
                                     
                                       
                                         log 
                                         10 
                                       
                                       ⁡ 
                                       
                                         ( 
                                         
                                           
                                             
                                               
                                                 P 
                                                 ^ 
                                               
                                               
                                                 CMAX 
                                                 , 
                                                 c 
                                               
                                             
                                             ⁡ 
                                             
                                               ( 
                                               i 
                                               ) 
                                             
                                           
                                           - 
                                           
                                             
                                               
                                                 P 
                                                 ^ 
                                               
                                               PUSCCH 
                                             
                                             ⁡ 
                                             
                                               ( 
                                               i 
                                               ) 
                                             
                                           
                                         
                                         ) 
                                       
                                     
                                   
                                   , 
                                 
                               
                             
                             
                               
                                 
                                   
                                     
                                       
                                         
                                           10 
                                           ⁢ 
                                           
                                             
                                               log 
                                               10 
                                             
                                             ⁡ 
                                             
                                               ( 
                                               
                                                 
                                                   M 
                                                   
                                                     PUSCH 
                                                     , 
                                                     c 
                                                   
                                                 
                                                 ⁡ 
                                                 
                                                   ( 
                                                   i 
                                                   ) 
                                                 
                                               
                                               ) 
                                             
                                           
                                         
                                         + 
                                         
                                           
                                             P 
                                             
                                               
                                                 O 
                                                 ⁢ 
                                                 _ 
                                                 ⁢ 
                                                 PUSCH 
                                               
                                               , 
                                               c 
                                             
                                           
                                           ⁡ 
                                           
                                             ( 
                                             j 
                                             ) 
                                           
                                         
                                         + 
                                       
                                     
                                   
                                   
                                     
                                       
                                         
                                           
                                             
                                               α 
                                               c 
                                             
                                             ⁡ 
                                             
                                               ( 
                                               j 
                                               ) 
                                             
                                           
                                           · 
                                           
                                             PL 
                                             c 
                                           
                                         
                                         + 
                                         
                                           
                                             Δ 
                                             
                                               TF 
                                               , 
                                               c 
                                             
                                           
                                           ⁡ 
                                           
                                             ( 
                                             i 
                                             ) 
                                           
                                         
                                         + 
                                         
                                           
                                             f 
                                             c 
                                           
                                           ⁡ 
                                           
                                             ( 
                                             i 
                                             ) 
                                           
                                         
                                       
                                     
                                   
                                 
                               
                             
                           
                           } 
                         
                         ⁢ 
                         
                             
                         
                         [ 
                         dBm 
                         ] 
                       
                     
                   
                   ; 
                 
               
               
                 
                   ( 
                   2 
                   ) 
                 
               
             
           
         
       
     
     and a power control formula of the PUCCH is: 
     
       
         
           
             
               
                 
                   
                     
                       P 
                       PUCCH 
                     
                     ⁡ 
                     
                       ( 
                       i 
                       ) 
                     
                   
                   = 
                   
                       
                   
                   ⁢ 
                   
                     min 
                     ⁢ 
                     
                       
                         
                           { 
                           
                             
                               
                                 
                                   
                                     
                                       P 
                                       
                                         CMAX 
                                         , 
                                         c 
                                       
                                     
                                     ⁡ 
                                     
                                       ( 
                                       i 
                                       ) 
                                     
                                   
                                   , 
                                 
                               
                             
                             
                               
                                 
                                   
                                     
                                       
                                         
                                           P 
                                           
                                             0 
                                             ⁢ 
                                             
                                               _ 
                                               ⁢ 
                                               PUCCH 
                                             
                                           
                                         
                                         + 
                                         
                                           PL 
                                           c 
                                         
                                         + 
                                         
                                           h 
                                           ⁡ 
                                           
                                             ( 
                                             
                                               
                                                 n 
                                                 CQI 
                                               
                                               , 
                                               
                                                 n 
                                                 HARQ 
                                               
                                               , 
                                               
                                                 n 
                                                 SR 
                                               
                                             
                                             ) 
                                           
                                         
                                         + 
                                       
                                     
                                   
                                   
                                     
                                       
                                         
                                           
                                             Δ 
                                             
                                               
                                                 F 
                                                 ⁢ 
                                                 _ 
                                                 ⁢ 
                                                 PUCCH 
                                               
                                               , 
                                               c 
                                             
                                           
                                           ⁡ 
                                           
                                             ( 
                                             F 
                                             ) 
                                           
                                         
                                         + 
                                         
                                           
                                             Δ 
                                             TxD 
                                           
                                           ⁡ 
                                           
                                             ( 
                                             
                                               F 
                                               ′ 
                                             
                                             ) 
                                           
                                         
                                         + 
                                         
                                           g 
                                           ⁡ 
                                           
                                             ( 
                                             i 
                                             ) 
                                           
                                         
                                       
                                     
                                   
                                 
                               
                             
                           
                           } 
                         
                         ⁢ 
                         
                             
                         
                         [ 
                         dBm 
                         ] 
                       
                       . 
                     
                   
                 
               
               
                 
                   ( 
                   3 
                   ) 
                 
               
             
           
         
       
     
     In the LTE system, if the UE is configured to be unable to transmit the PUSCH and the PUCCH at the same time, the same UE will not transmit the PUSCH and the PUCCH in the same one or more carriers in the same subframe at the same time. And when the UE is configured to be able to transmit the PUSCH and the PUCCH at the same time, the same UE may transmit the PUSCH and the PUCCH in the same one or more carriers in the same subframe at the same time. However, the PUCCH is only transmitted in a primary component carrier (PCC). Uplink control information (UCI) carried by the PUSCH contains UCI of all corresponding carriers, and the uplink information can only be transmitted in a PUSCH in a carrier. That is, the UCI of all the corresponding carriers is either combined, or partially dropped according to a predetermined criterion, and is finally transmitted via a PUCCH and/or a PUSCH in a CC only. 
     When transmission power of the uplink signal exceeds configured maximum output power (PCMAX) of the UE, that is, outflow of the output power of the UE occurs, transmission power used by the UE in transmitting the above uplink signal will be equal to the PCMAX of the UE. And the UE will adjust power of a corresponding uplink channel. 
       FIG. 1  is a schematic diagram of simultaneously transmitting multiple PUCCHs by a UE in an LTE-A system at different cells in the same subframe,  FIG. 2  is a schematic diagram of simultaneously transmitting multiple PUSCHs by a UE in an LTE-A system at different cells in the same subframe,  FIG. 3  is a schematic diagram of simultaneously transmitting PUCCHs and PUSCHs by a UE in an LTE-A system at different cells in the same subframe, and  FIG. 4  is a schematic diagram of simultaneously transmitting PUCCHs and PUSCHs by a UE in an LTE-A system at a primary serving cell in the same subframe. 
     As shown in  FIG. 1 , as a carrier aggregation technique is used, when the UE is configured with multiple serving cells, simultaneous transmission of multiple PUCCHs at different serving cells in the same subframe will occur; or as shown in  FIG. 2 , multiple PUSCHs are simultaneously transmitted at different serving cells; or, as shown in  FIG. 3 , the PUCCHs and PUSCHs are simultaneously transmitted. And on the other hand, as abilities of the UE are enhanced, as shown in  FIG. 4 , the UE may simultaneously transmit the PUCCHs and PUSCHs at the primary serving cell in the same subframe. 
     When the above case occurs, that is, the UE needs to simultaneously transmit multiple PUSCHs in the same subframe, or the UE needs to simultaneously transmit PUSCHs and PUCCHs, it will occur that a total sum of transmission power of multiple PUSCHs is greater than the PCMAX of the UE, or a total sum of transmission power of PUSCHs and PUCCHs is greater than the PCMAX of the UE. In order to direct transmission power allocation of the UE in such a case, a power control method in a case where transmission power of a UE is limited is defined in LTE-A standardization, which is as follows: 
     when only multiple PUSCHs with no UCI need to be simultaneously transmitted, if total transmission power obtained at this moment exceeds the PCMAX of the UE, the UE lowers the transmission power by equal share in each PUSCH, until it is ensured that the total transmission power is less than or equal to the PCMAX of the UE; 
     when PUSCHs with no UCI and PUCCHs need to be simultaneously transmitted, if total transmission power obtained at this moment exceeds the PCMAX of the UE, the UE first ensures that the transmission power of the PUCCHs is satisfied, and then lowers the transmission power by equal share in each PUSCH with no UCI, until it is ensured that the total transmission power is less than or equal to the PCMAX of the UE, as shown in formula (4); 
     for example, when the PUSCHs with no UCI and PUCCHs are simultaneously transmitted, the transmission power of the PUCCHs is preferentially ensured: 
     
       
         
           
             
               
                 
                   
                     
                       
                         ∑ 
                         c 
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                         · 
                         
                           
                             
                               P 
                               ^ 
                             
                             
                               PUSCH 
                               , 
                               c 
                             
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                       
                     
                     ≤ 
                     
                       ( 
                       
                         
                           
                             
                               P 
                               ^ 
                             
                             CMAX 
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                         - 
                         
                           
                             
                               P 
                               ^ 
                             
                             PUCCH 
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                       
                       ) 
                     
                   
                   ; 
                 
               
               
                 
                   ( 
                   4 
                   ) 
                 
               
             
           
         
       
     
     when PUSCHs with no UCI and PUSCHs with UCI need to be simultaneously transmitted, if total transmission power obtained at this moment exceeds the PCMAX of the UE, the UE first ensures that the transmission power of the PUSCHs with UCI is satisfied, and then lowers the transmission power by equal share in each PUSCH with no UCI, until it is ensured that the total transmission power is less than or equal to the PCMAX of the UE, as shown in formula (5); 
     for example, when the PUSCHs with no UCI and PUSCHs with UCI are simultaneously transmitted, the transmission power of the PUSCHs with UCI is preferentially ensured: 
     
       
         
           
             
               
                 
                   
                     
                       
                         ∑ 
                         
                           c 
                           ≠ 
                           j 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                         · 
                         
                           
                             
                               P 
                               ^ 
                             
                             
                               PUSCH 
                               , 
                               c 
                             
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                       
                     
                     ≤ 
                     
                       ( 
                       
                         
                           
                             
                               P 
                               ^ 
                             
                             CMAX 
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                         - 
                         
                           
                             
                               P 
                               ^ 
                             
                             
                               PUSCH 
                               , 
                               j 
                             
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                       
                       ) 
                     
                   
                   ; 
                 
               
               
                 
                   ( 
                   5 
                   ) 
                 
               
             
           
         
       
     
     when PUCCHs, PUSCHs with no UCI and PUSCHs with UCI need to be simultaneously transmitted, if total transmission power obtained at this moment exceeds the PCMAX of the UE, the UE first ensures that the transmission power of the PUCCHs is satisfied, then the transmission power of the PUSCHs with UCI is satisfied, and thereafter lowers the transmission power by equal share in each PUSCH with no UCI, until it is ensured that the total transmission power is less than or equal to the PCMAX of the UE, as shown in formula (6); 
     for example, when the PUCCHs, PUSCHs with UCI and PUSCHs with no UCI are simultaneously transmitted, the transmission power of the PUCCHs is ensured first, then the transmission power of the PUSCHs with UCI is ensured, and thereafter the transmission power of the PUSCHs with no UCI is ensured: 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           P 
                           ^ 
                         
                         
                           PUSCH 
                           , 
                           j 
                         
                       
                       ⁡ 
                       
                         ( 
                         i 
                         ) 
                       
                     
                     = 
                     
                       min 
                       ⁡ 
                       
                         ( 
                         
                           
                             
                               
                                 P 
                                 ^ 
                               
                               
                                 PUSCH 
                                 , 
                                 j 
                               
                             
                             ⁡ 
                             
                               ( 
                               i 
                               ) 
                             
                           
                           , 
                           
                             ( 
                             
                               
                                 
                                   
                                     P 
                                     ^ 
                                   
                                   CMAX 
                                 
                                 ⁡ 
                                 
                                   ( 
                                   i 
                                   ) 
                                 
                               
                               - 
                               
                                 
                                   
                                     P 
                                     ^ 
                                   
                                   PUCCH 
                                 
                                 ⁡ 
                                 
                                   ( 
                                   i 
                                   ) 
                                 
                               
                             
                             ) 
                           
                         
                         ) 
                       
                     
                   
                   , 
                   
                     
 
                   
                   ⁢ 
                   
                     
                       
                         ∑ 
                         
                           c 
                           ≠ 
                           j 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                         · 
                         
                           
                             
                               P 
                               ^ 
                             
                             
                               PUSCH 
                               , 
                               c 
                             
                           
                           ⁡ 
                           
                             ( 
                             i 
                             ) 
                           
                         
                       
                     
                     ≤ 
                     
                       
                         ( 
                         
                           
                             
                               
                                 P 
                                 ^ 
                               
                               CMAX 
                             
                             ⁡ 
                             
                               ( 
                               i 
                               ) 
                             
                           
                           - 
                           
                             
                               
                                 P 
                                 ^ 
                               
                               PUCCH 
                             
                             ⁡ 
                             
                               ( 
                               i 
                               ) 
                             
                           
                           - 
                           
                             
                               
                                 P 
                                 ^ 
                               
                               
                                 PUSCH 
                                 , 
                                 j 
                               
                             
                             ⁡ 
                             
                               ( 
                               i 
                               ) 
                             
                           
                         
                         ) 
                       
                       . 
                     
                   
                 
               
               
                 
                   ( 
                   6 
                   ) 
                 
               
             
           
         
       
     
     Power control of an uplink channel for a serving cell, or power control of transmitting an uplink channel by a primary serving cell and a secondary serving cell under a multicarrier technology, is only defined in the current standards. 
     However, as continuous development of small base stations, there will occur a scenario in Rel. 12 where there exist multiple small base stations under coverage of a macro base station (such as an eNB). Coverage of the small base stations is relatively small, and the number of them is relatively large. The small base stations may occupy frequency points different from or identical to those occupied by the macro base station. Backhauls between the small base stations and the macro base station may be ideal, that is, latency is very small or may be completely neglectable, and a transmission ability is powerful. And more typically, the backhauls are non-ideal, that is, transmission latency is relatively large and the transmission ability is limited. The power control of the uplink channel of the UE in such scenarios are not taken into account in the current standards. 
     It should be noted that the above description of the background is merely provided for clear and complete explanation of the present disclosure and for easy understanding by those skilled in the art. And it should not be understood that the above technical solution is known to those skilled in the art as it is described in the background of the present disclosure. 
     SUMMARY 
     When a UE transmits uplink signals to at least two cells in the same subframe, power allocation may be performed on the uplink signals according to a predetermined priority criterion. According to an existing priority criterion, such as PUCCH&gt;PUSCH with UCI&gt;PUSCH, in a case where total uplink power is limited, power of PUCCHs may be allocated first, then power is allocated from the remained power for channels of lower priorities, and if there is no remained power, the channels of lower priorities will not be transmitted. 
     It was found by the inventors that when the UE keeps in connection with two base stations, it is possible that signaling carried by the two base stations and traffic types are different, hence, it is possible that performance required by the two base stations is different. For example, it is possible that a macro base station carries signaling, and a small base station only carries data. Then, in order to ensure performance of control signaling, transmission in the macro base station needs to reach more robust performance. Therefore, when the UE transmits the uplink signals to the two base stations at the same time, it also needs to carry an uplink performance requirement of important information. 
     If power allocation is performed on uplink signals of at least two cells, or uplink channels are selected, a case may possibly occur where an important channel cannot be transmitted due to insufficient of the allocated power. For example, as a priority of a PUSCH with UCI of the macro base station is lower than that of a PUCCH of a small base station, if power of the PUCCH of the small base station is allocated first and then power is allocated from the remained power for the PUSCH with UCI of the macro base station, the power allocated for the PUSCH with UCI of the macro base station may be insufficient, which results in that important information cannot be transmitted in time and hence the whole performance is degraded. 
     Embodiments of the present disclosure provide a method for controlling power of an uplink channel, a UE and a communication system. In a case where power of the UE is limited, by taking power needed by uplink channels of relatively low priorities into account, not only power may be allocated for uplink channels of relatively high priorities, but also the uplink channels of relatively low priorities may be transmitted in time, thereby further improving whole performance of uplink information transmission. 
     According to an aspect of the embodiments of the present disclosure, there is provided a method for controlling power of an uplink channel, applicable to a UE keeping in connection with at least two cells, the method including: 
     sorting, by the UE, priorities of uplink channels of the at least two cells, when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe; and 
     allocating power for the uplink channels of the at least two cells according to a result of priority sorting; wherein when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     According to another aspect of the embodiments of the present disclosure, there is provided a UE, which keeps in connection with at least two cells, the UE including: 
     a priority determining unit configured to sort priorities of uplink channels of the at least two cells when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe; and 
     a power controlling unit configured to allocate power for the uplink channels of the at least two cells according to a result of priority sorting; wherein when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     According to a further aspect of the embodiments of the present disclosure, there is provided a communication system, including: 
     a UE keeping in connection with at least two cells and configured to sort priorities of uplink channels of the at least two cells when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe, and allocate power for the uplink channels of the at least two cells according to a result of priority sorting; wherein when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     According to still another aspect of the embodiments of the present disclosure, there is provided a computer-readable program, wherein when the program is executed in a UE, the program enables the UE to carry out the method for controlling power of an uplink channel as described above. 
     According to yet another aspect of the embodiments of the present disclosure, there is provided a storage medium in which a computer readable program is stored, wherein the computer readable program enables a UE to carry out the method for controlling power of an uplink channel as described above. 
     An advantage of the embodiments of the present disclosure exists in that in a case where power of the UE is limited, by taking power needed by uplink channels of relatively low priorities into account, not only power may be allocated for uplink channels of relatively high priorities, but also the uplink channels of relatively low priorities may be transmitted in time, thereby further improving whole performance of uplink information transmission. 
     With reference to the following description and drawings, the particular embodiments of the present disclosure are disclosed in detail, and the principle of the present disclosure and the manners of use are indicated. It should be understood that the scope of the embodiments of the present disclosure is not limited thereto. The embodiments of the present disclosure contain many alternations, modifications and equivalents within the scope of the terms of the appended claims. 
     Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments. 
     It should be emphasized that the term “comprise/include” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. To facilitate illustrating and describing some parts of the disclosure, corresponding portions of the drawings may be exaggerated in size. 
     Elements and features depicted in one drawing or embodiment of the disclosure may be combined with elements and features depicted in one or more additional drawings or embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views and may be used to designate like or similar parts in more than one embodiments. 
    
    
     
         FIG. 1  is a schematic diagram of simultaneously transmitting multiple PUCCHs by a UE in an LTE-A system at different cells in the same subframe; 
         FIG. 2  is a schematic diagram of simultaneously transmitting multiple PUSCHs by a UE in an LTE-A system at different cells in the same subframe; 
         FIG. 3  is a schematic diagram of simultaneously transmitting PUCCHs and PUSCHs by a UE in an LTE-A system at different cells in the same subframe; 
         FIG. 4  is a schematic diagram of simultaneously transmitting PUCCHs and PUSCHs by a UE in an LTE-A system at a primary serving cell in the same subframe; 
         FIG. 5  is a flowchart of the method for controlling power of an embodiment of the present disclosure; 
         FIG. 6  is a schematic diagram of keeping in connection by the UE with a macro eNB and a small base station; 
         FIG. 7  is another schematic diagram of keeping in connection by the UE with the macro eNB and the small base station; 
         FIG. 8  is a further schematic diagram of keeping in connection by the UE with the macro eNB and the small eNB; 
         FIG. 9  is still another schematic diagram of keeping in connection by the UE with the macro base station and the small base station: 
         FIG. 10  is yet another schematic diagram of keeping in connection by the UE with the macro base station and the small base station; 
         FIG. 11  is a schematic diagram of a structure of the apparatus for controlling power of an embodiment of the present disclosure; 
         FIG. 12  is a schematic diagram of a structure of the UE of an embodiment of the present disclosure; and 
         FIG. 13  is a schematic diagram of a structure of the communication system of an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     These and further aspects and features of the present disclosure will be apparent with reference to the following description and attached drawings. In the description and drawings, particular embodiments of the disclosure have been disclosed in detail as being indicative of some of the ways in which the principles of the disclosure may be employed, but it is understood that the disclosure is not limited correspondingly in scope. Rather, the disclosure includes all changes, modifications and equivalents coming within the terms of the appended claims. 
     Embodiment 1 
     An embodiment of the present disclosure provides a method for controlling power of an uplink channel, applicable to a UE keeping in connection with at least two cells.  FIG. 5  is a flowchart of the method for controlling power of the embodiment of the present disclosure. As shown in  FIG. 5 , the method includes: 
     step  501 : the UE sorts priorities of uplink channels of the at least two cells, when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe; and 
     step  502 : the UE allocates power for the uplink channels of the at least two cells according to a result of priority sorting; wherein when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     In this embodiment, the at least two cells may be formed by a macro base station and a small base station. For example, they may be a macro cell under a macro base station and one or more small cells under a small base station (small cell eNB), may also be a primary cell at a dominant position and one or more secondary cell at subordinate positions, or may also be multiple small cells, and the present disclosure is not limited thereto. Following description is given taking only two cells as an example, cases of more than two cells are similar to this. 
     In this embodiment, taking a case where the power of the UE is limited into account, if the power of the UE is not limited, a solution in the relevant art may be used, which shall not be described herein any further. There may exist a non-ideal backhaul between base stations of the at least two cells; however, the present disclosure is not limited thereto. Multiple cells belonging to the same base station and connected by ideal backhauls may be dealt with by using the relevant art. 
     In this embodiment, in the same subframe may refer to subframes of identical subframe indices; however, the present disclosure is not limited thereto. For example, if the two cells are not synchronized, in the same subframe is not limited to be subframes of identical subframe indices, but may be a period of time of the same length as a subframe in a time dimension. 
     In this embodiment, before step  501 , the UE may generate ACK/NACK feedback according to a received downlink signal, or generate corresponding uplink control information according to a period and an offset configured for periodic CSI (Channel State Information) or according to received aperiodic CSI triggering indication or according to a request for needed resources of an uplink traffic. 
     After step  502 , the UE may transmit a signal of an uplink channel according to a result of power allocation for the uplink channel. The relevant art may be referred to for particular contents of generation of the UCI, and transmission of the uplink channel, etc. 
     In an implementation, taking a PUCCH as an example, uplink channels of the at least two cells may include: a PUCCH for a cell and a PUCCH for another cell. Whether the UE needs to transmit a PUCCH at a serving cell in the same subframe and transmit PUCCHs at other serving cells may be determined first. And the sorting priorities of uplink channels of the at least two cells may particularly include: determining priorities of the PUCCHs according to a type of the UCI contained in the PUCCHs, and/or types or indices of the at least two cells. 
     In another implementation, taking a PUSCH as an example, uplink channels of the at least two cells may include: a PUSCH for a cell and a PUSCH for another cell. And the sorting priorities of uplink channels of the at least two cells may particularly include: determining priorities of the PUSCHs according to a type of the UCI contained in the PUSCHs, and/or types or indices of the at least two cells. 
     In a further implementation, taking a PUCCH and a PUSCH as an example, uplink channels of the at least two cells may include: a PUCCH for a cell and a PUSCH for another cell. And the sorting priorities of uplink channels of the at least two cells may particularly include: determining priorities of the uplink channels according to any one of a type of the UCI contained in the uplink channels, types or indices of the at least two cells, and types of the uplink channels, or a combination thereof. 
     It should be noted that the uplink channels of the at least two cells and the sorting the priorities of the uplink channels of the at least two cells are illustrated only; however, the present disclosure is not limited thereto. Relevant technologies, such as PCT/CN2013/081382, etc., may be referred to for uplink channels of at least two cells and sorting priorities. 
     In this embodiment, the priorities of the uplink channels of the at least two cells may be sorted according to a predetermined priority criterion first. The predetermined priority criterion may be: determining a sort of priorities according to a type of an uplink signal, or a content carried by the uplink signal, and/or a type of a base station. 
     After the priorities are determined, power allocation is performed on the uplink channels in a descending sort of the priorities, that is, power allocation is performed first on an uplink channel of a high priority. Transmission power needed by an uplink channel of a low priority (which may also be referred to as needed power, or lowest transmission power) needs to be taken into account in the allocated power. For example, lowest transmission power of uplink signals in cells or base stations may be set. Then, when the power allocation is performed on the uplink channel of a high priority, it needs to be ensured that sufficient transmission power is reserved for satisfying the lowest transmission power of the uplink channel of a low priority. 
     In this embodiment, power Pi allocated for an i-th uplink channel may be obtained according to a formula as below: 
     
       
         
           
             
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     where, 1, . . . , M are indices of the uplink channels with priorities being sorted descendingly, M is the number of the uplink channels with priorities being sorted, P cmax  is the maximum uplink transmission power (that is PCMAX) of the UE, P de   _   i  refers to transmission power adopted by the UE for the i-th uplink channel expected by a base station, and P min   _   i  is power needed by a j-th uplink channel. 
     The PCMAX (may also be named as Pcmax) of the UE and power needed by the uplink channels need to satisfy a condition as below: 
     
       
         
           
             
               
                 
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     In this embodiment, the power needed by the uplink channels may be predetermined, and may be configured for different base stations; for example, needed power may be configured for each of the different base stations, and power needed by uplink channels under the same base station is identical; or needed power may be configured for different cells; for example, needed power may be configured for each of the different cells, and need power of uplink channels under the same cell is identical; or needed power may be configured for different uplink channels. 
     It should be noted that the above formula is a particular implementation of the present disclosure only; however, the present disclosure is not limited thereto. For example, the above formula may be suitably adjusted. In performing power allocation on an uplink channel of a relatively high priority, needed power of one or more uplink channels of relatively low priorities needs only to be taken into account, and this will fall within the protection scope of the present disclosure. 
     Taking that needed power of different uplink channels is configured for different base stations as an example, assuming that minimum transmission power of the uplink signals at the base stations is P min   _   eNBi  and the minimum transmission power of the base stations may be less than or equal to the PCMAX P cmax  of the UE, when the UE allocates uplink power for an uplink channel of a high priority of a base station i, it may be that P i =min(P des   _   i , P cmax −a sum of actual transmission power P i  of all base stations of priorities higher than that of the current base station—a sum of minimum P min   _   eNBi  of all base stations of priorities lower than that of the current base station); where, P des   _   i  is the transmission power used by the UE that is expected by the base station, such as the power calculated by using formulae (1), (2) and (3). 
     When the UE allocates power for uplink channels of low priorities of a base station j, it needs to ensure that its available power is not less than its minimum transmission power, which may be, for example, P j =max(P cmax −a sum of actual transmission power P i  of all base stations of priorities higher than that of the current base station, P min   _   eNBj ). 
     In this embodiment, assuming that the UE is connected to a macro base station and a small base station at the same time and there is only one cell under each base station keeping in connection with the UE, when the UE transmits uplink signals to the macro base station and the small base station at the same time, if a sum of needed power of two uplink signals exceeds the PCMAX of the UE, priority sorting and power allocation will be performed on the two uplink signals. 
       FIG. 6  is a schematic diagram of keeping in connection by the UE with a macro base station and small base stations. As shown in  FIG. 6 , the UE may keep in connection with the macro base station by using a frequency f 1 , and keep in connection with a small base station by using a frequency f 2 .  FIG. 7  is another schematic diagram of keeping in connection by the UE with a macro base station and small base stations. As shown in  FIG. 7 , the UE may keep in connection with the macro base station by using the frequency f 1 , and keep in connection with a small base station by also using the frequency f 1 . And  FIG. 8  is a further schematic diagram of keeping in connection by the UE with a macro base station and small base stations. As shown in  FIG. 8 , the UE may keep in connection with the macro base station by using the frequency f 1 , keep in connection with a small base station by using the frequency f 2 , and keep in connection with another small base station by also using the frequency f 2 . 
     As shown in  FIGS. 6-8 , the UE may operate under carrier aggregation (inter-eNB) similar to that under different eNBs. As small base stations and a macro base station belong to different eNBs and the backhauls are non-ideal, uplink control signals are more suitable to be transmitted in uplink channels of the eNBs. Then, it may possibly occur that PUCCHs are simultaneously transmitted in the small base stations and the macro base station, or PUSCHs containing UCI are transmitted in the small base stations and PUSCHs containing UCI are also transmitted in the macro base station, or PUSCHs containing UCI are transmitted in the small base stations and PUCCHs are transmitted in the macro base station, or PUCCHs are transmitted in the small base stations and PUSCHs containing UCI are transmitted in the small base stations, or PUCCHs and PUSCHs containing UCI are transmitted in the small base stations and only PUCCHs are transmitted in the macro base station, or PUCCHs and PUSCHs containing UCI are transmitted in the macro base station and only PUCCHs are transmitted in the small base stations, or PUCCHs and PUSCHs containing UCI are transmitted in the small base stations and only PUSCHs containing UCI are transmitted in the macro base station, or PUCCHs and PUSCHs containing UCI are transmitted in the macro base station and only PUSCHs containing UCI are transmitted in the small base stations, or PUCCHs and PUSCHs containing UCI are transmitted in the small base stations and PUCCHs and PUSCHs containing UCI are also transmitted in the macro base station. Combinations of the PUCCHs, PUSCHs containing UCI and PUSCHs containing no UCI shall not be described herein any further. 
     It should be noted that the UE keeping in connection with a macro base station and small base stations is only illustrated above; however, the present disclosure is not limited thereto. The embodiments of the present disclosure shall be described in detail taking the scenarios shown in  FIGS. 6-8  as examples. 
     For example, assuming that the UE transmit PUSCHs to the macro base station and transmit PUCCHs to the small base stations, if a priority criterion is followed, for example, according to a type of information carried by uplink channels, a channel containing physical layer control information is preferential over a channel containing no physical layer control information, that is, priorities of PUCCHs of small base stations are higher than those of PUCCHs of a macro base station, then the UE will allocate power for the PUCCHs of the small base stations, and then allocate power for the PUSCHs of the macro base station. 
     Assuming that in scheduling by the base stations, respectively expected uplink transmission power values are 4 and 8 and maximum uplink transmission power of the UE is 10, a sum of the two pieces of power, 12, exceeds the maximum uplink transmission power of the UE. And assuming that predetermined minimum transmission power of uplink signals of two base stations is 5 for the macro base station and 2 for the small base station, respectively, in allocating power first by the UE for the small base station, it needs to ensure that after the power is allocated for the PUCCHs of the small base station, the remained power is greater than or equal to 5, that is, final transmission power of the PUCCHs of the small base station is P i =min(P des   _   i , Pcmax−P min   _   MeNB )=min(4, 10−5)=4. And final transmission power of the PUSCHs of the macro base station is P j =max(Pcmax−Pi, P min   _   MeNB )=max(10−4, 5)=6. 
     For another example, assuming that the UE transmit PUSCHs to the macro base station and transmit PUCCHs to the small base stations, if a priority criterion is followed, for example, according to a type of information carried by uplink channels, a channel containing physical layer control information is preferential over a channel containing no physical layer control information, that is, priorities of PUCCHs of small base stations are higher than those of PUCCHs of a macro base station, then the UE will allocate power for the PUCCHs of the small base stations, and then allocate power for the PUSCHs of the macro base station. 
     Assuming that in scheduling by the base stations, respectively expected uplink transmission power values are 6 and 8 and maximum uplink transmission power of the UE is 10, a sum of the two pieces of power, 14, exceeds the maximum uplink transmission power of the UE. And assuming that predetermined minimum transmission power of uplink signals of two base stations is 5 for the macro base station and 2 for the small base station, respectively, in allocating power first by the UE for the small base station, it needs to ensure that after the power is allocated for the PUCCHs of the small base station, the remained power is greater than or equal to 5, that is, final transmission power of the PUCCHs of the small base station is P j =min(P des   _   i , Pcmax−P min   _   MeNB )=min(6, 10−5)=5. And final transmission power of the PUSCHs of the macro base station is P j =max(Pcmax−Pi, P min   _   MeNB )=max(10-6, 5)=5. 
     In this embodiment, the UE may receive high-layer configuration information transmitted by the base station, and directly configure needed power of the uplink signals according to the high-layer configuration information; or determine the needed power according to an interval provided by the high-layer configuration information, and configure the needed power of the uplink signals according to the determined needed power. In the above two examples, the minimum transmission power of the base station is configured via a high layer, or is determined by the UE based on an interval provided by high-layer configuration information. 
     In this embodiment, different needed power may be configured according to different types of the uplink channels. For example, different minimum transmission power may be configured for the PUCCHs, PUSCHs with UCI and PUSCHs with no UCI. Or different needed power may be configured according to different carrying contents carried by the uplink channels. For example, different minimum transmission power may be determined according to carrying types carried by the PUSCHs/PUCCHs, and minimum transmission power of PUSCHs carrying control signaling may set to be relatively large. 
     In this embodiment, the needed power of the uplink channels may be configured for different cells. Different needed power may be configured for different cells under the same base station. For example, the UE may keep in connection with multiple cells under a base station; minimum transmission power configured for a primary cell (PCell) of the UE may be greater than that of other cells. And furthermore, when minimum transmission power is configured for each cell, minimum transmission power may not be configured for each base station. 
       FIG. 9  is still another schematic diagram of keeping in connection by the UE with the macro base station and the small base station. As shown in  FIG. 9 , the UE may keep in connection with a cell under the macro base station by using the frequency f 1 , and keep in connection with two cells of a small base station by using frequencies f 2  and f 3 , respectively. The embodiment of the present disclosure shall be described in detail taking the scenario shown in  FIG. 9  as an example. 
     For example, it is assumed that the UE is connected to a macro base station and a small base station at the same time, and a cell under the macro base station and two cell under the small base station keep in connection with the UE. And it is assumed that the macro base station is an MeNB, a cell A under the macro base station is a PCell, and the small base station is an SeNB, a cell B under the small base station is a Pcell, and a cell C under the small base station is an Scell. 
     Then, when the UE transmit uplink signals at the same time to the cell A of the macro base station and the cell B of the small base station, if a sum of needed power of two uplink signals exceeds the PCMAX of the UE, priority sorting and power allocation will be performed on the two uplink signals. Assuming that the UE transmits PUSCHs with ACK/NACK to the macro base station and transmits PUCCHs with CSI to the small base station, if a priority criterion is followed, for example, when physical layer control information is contained, a priority of the ACK/NACK is higher than that periodic CSI, and priorities of the PUSCHs of the macro base station are higher than those of the PUCCHs of the small base station, the UE will allocate power for the PUSCHs of the macro base station, and then for the PUCCHs of the cell B of the small base station. 
     Assuming that in scheduling by the base stations, respectively expected uplink transmission power values are 10 and 4 and maximum uplink transmission power of the UE is 10, a sum of the two pieces of power, 14, exceeds the maximum uplink transmission power of the UE. And assuming that predetermined minimum transmission power of uplink signals of two base stations is 5 for the cell A of the macro base station, 4 for the cell B of the small base station and 2 for the cell C of the small base station, respectively. 
     Then, in allocating power first by the UE for the PUSCHs of the macro base station, it needs to ensure that after the power is allocated for the PUSCHs of the macro base station, the remained power is greater than or equal to the minimum transmission power, 4, of the cell B of the small base station, that is, final transmission power of the PUSCHs of the cell A of the macro base station is P A =min(P des   _   A , Pcmax−P min   _   cellB )=min(10, 10−4)=6, and final transmission power of the PUCCHs of the cell B of the small base station is P B =max(Pcmax−P A , P min   _   cellB )=max(10−7, 4)=4. And when the UE transmit uplink signals at the same time to the cell A of the macro base station and the cell C of the small base station, if the priority of the cell A of the macro base station is still highest according to the priority criterion, the final transmission power of the PUSCHs of the cell A of the macro base station is P A =min(P des   _   A , Pcmax−P min   _   cellC )=min(10, 10−2)=8, and final transmission power of the cell C of the small base station is P C =max(Pcmax−P A , P min   _   cellC )=max(10−8, 2)=2. 
       FIG. 10  is yet another schematic diagram of keeping in connection by the UE with the macro base station and the small base station. As shown in  FIG. 10 , the UE may keep in connection with two cells of the macro base station by using the frequencies f 1  and f 2 , respectively, and keep in connection with a cell of the small base station by using the frequency f 3 . The embodiment of the present disclosure shall be described in detail taking the scenario shown in  FIG. 10  as an example. 
     For example, it is assumed that the UE is connected to the cells A and B of the macro base station and the cell C of the small base station at the same time, and at the same time, transmit uplink signals. And if a sum of needed power of three uplink signals exceeds the PCMAX of the UE, priority sorting and power allocation will be performed on the three uplink signals. 
     It is assumed that the UE transmits PUCCHs with ACK/NACK to the cell A of the macro base station (Pcell), transmits PUSCHs with CSI to the cell B of the macro base station (Scell) and transmits PUSCHs to the cell C of the small base station. If expected power in scheduling by the base stations is 10, 7 and 3, respectively, a sum of three pieces of power exceeds the PCMAX 10 of the UE, hence, priority sorting and power allocation need to be performed on the three pieces of power. 
     It is assumed that minimum transmission power of the three pieces of power is 6, 4 and 1, respectively. According to the priority criterion, the PUCCHs with ACK/NACK of the cell A&gt;the PUSCHs with CSI of the cell B&gt;the PUSCHs of the cell C. Then, power allocation is first performed on the cell A, P A =min(P des   _   A , Pcmax−P min   _   cellB −P min   _   cellC )=min(10, 10−4−1)=5, then power allocation is performed on the cell B, P B =min(P des   _   B , Pcmax−P A −P min   _   cellC )=min(7, 10−5−1)=4, and power allocation is finally performed on the cell C, P C =max(Pcmax−P A −P B , P min   _   cellC )=1. 
     In this embodiment, in allocating transmission power for the uplink channels of the different base stations, power of one or more cells in each base station may only be taken into account, and power of which cell is taken into account may be determined according to priorities of the cells in a base station. For example, priority sorting may be first performed in a base station, and power of a cell in each base station of a highest priority is only taken into account in calculating the transmission power of the uplink signals of the different base stations, that is, if only one cell of a base station is taken into account, this cell is a cell of a highest priority in a single base station. 
     For example, in the above example, within the macro base station, the priority of the cell A is higher than that of the cell B. Hence, power allocation may be first performed on the cell A, P A =min(P des   _   A , Pcmax−P min   _   cellC )=min(10, 10−1)=9, then power allocation is performed on the cell B, P B =min(P des   _   B , Pcmax−P A −P min   _   cellC )=min(7, 10−9−1)=0, and power allocation is finally performed on the cell C, P C =max(Pcmax−P A −P B , P min   _   cellC )=1. 
     It can be seen from the above embodiment that in a case where the power of the UE is limited, by taking the needed power of the uplink channels of relatively low priorities into account, not only power may be allocated for uplink channels of high priorities, but also uplink channels of low priorities may be transmitted punctually, thereby further improving overall performance of uplink information transmission. 
     Embodiment 2 
     An embodiment of the present disclosure provides an apparatus for controlling power of an uplink channel, configured in a UE keeping in connection with at least two cells. This embodiment corresponds to the method for controlling power of an uplink channel described in Embodiment 1, with contents identical to those in Embodiment 1 being not going to be described herein any further. 
       FIG. 11  is a schematic diagram of a structure of the apparatus for controlling power of the embodiment of the present disclosure. As shown in  FIG. 11 , the apparatus  1100  for controlling power includes a priority determining unit  1101  and a power controlling unit  1102 . Other components of the apparatus  1100  for controlling power are not shown in the figure, and the relevant art may be referred to. 
     The priority determining unit  1101  is configured to sort priorities of uplink channels of the at least two cells when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe, and the power controlling unit  1102  is configured to allocate power for the uplink channels of the at least two cells according to a result of priority sorting; when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     In this embodiment, the power controlling unit  1102  is configured to perform the power allocation by using a formula below, power Pi allocated for an i-th uplink channel is: 
     
       
         
           
             
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               ⁢ 
               
                   
                 ; 
               
             
           
         
       
     
     where, 1, . . . , M are serial numbers of uplink channels with priorities being descendingly sorted, M is the number of the uplink channels of which priorities are sorted, P cmax  is maximum uplink transmission power of the UE, P des   _   i  is transmission power used by the UE for the i-th uplink channel that is expected by a base station, and P min   _   j  is needed power of a j-th uplink channel. 
     The maximum uplink transmission power of the UE and needed power of the uplink channels satisfy a condition as below: 
     
       
         
           
             
               
                 
                   P 
                   
                     c 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     max 
                   
                 
                 ≥ 
                 
                   
                     ∑ 
                     
                       
                         i 
                         = 
                         1 
                       
                       , 
                       … 
                       ⁢ 
                       
                           
                       
                       , 
                       M 
                     
                   
                   ⁢ 
                   
                     p 
                     
                       min_ 
                       ⁢ 
                       i 
                     
                   
                 
               
               ) 
             
             . 
           
         
       
     
     In this embodiment, the needed power of the uplink channels is configured for different base stations, or is configured for different cells, or is configured for different uplink channels. 
     In this embodiment, as shown in  FIG. 11 , the apparatus  1100  for controlling power may further include a configuring unit  1103  configured to receive high-layer configuration information transmitted by the base station, and configure directly the needed power of the uplink channels according to the high-layer configuration information; or determine needed power according to an interval provided by the high-layer configuration information, and configure the needed power of the uplink channels according to the determined needed power. 
     An embodiment of the present disclosure further provides a UE, including the apparatus  1100  for controlling power as described above. 
       FIG. 12  is a block diagram of a systematic structure of the UE  1200  of the embodiment of the present disclosure. As shown in  FIG. 5 , the UE  1200  may include a central processing unit  100  and a memory  140 , the memory  140  being coupled to the central processing unit  100 . It should be noted that this figure is illustrative only, and other types of structures may also be used, so as to supplement or replace this structure and achieve telecommunications function or other functions. 
     In an implementation, the functions of the apparatus  1100  for controlling power may be integrated into the central processing unit  100 . The central processing unit  100  may be configured to carry out the method for controlling power as described in Embodiment 1. 
     In another implementation, the apparatus  1100  for controlling power and the central processing unit  100  may be configured separately. For example, the apparatus  1100  for controlling power may be configured as a chip connected to the central processing unit  100 , with its functions being realized under control of the central processing unit  100 . 
     As shown in  FIG. 12 , the UE  1200  may further include a communication module  110 , an input unit  120 , an audio processor  130 , a display  160  and a power supply  170 . It should be noted that the UE  1200  does not necessarily include all the parts shown in  FIG. 12 . And furthermore, the UE  1200  may include components not shown in  FIG. 12 , and the relevant art may be referred to. 
     As shown in  FIG. 12 , the central processing unit  100  is sometimes referred to as a controller or control, and may include a microprocessor or other processor devices and/or logic devices. The central processing unit  100  is configured to receive input and control operations of every components of the UE  1200 . 
     The memory  140  may be, for example, one or more of a buffer memory, a flash memory, a hard drive, a mobile medium, a volatile memory, a nonvolatile memory, or other suitable devices. It may store information on a failure, and may further store programs executing related information. And the central processing unit  100  may execute the programs stored in the memory  140 , so as to realize information storage or processing, etc. Functions of other parts are similar to those of the relevant art, which shall not be described herein any further. The parts of the UE  1200  may be realized by specific hardware, firmware, software, or any combination thereof, without departing from the scope of the present disclosure. 
     It can be seen from the above embodiment that in a case where the power of the UE is limited, by taking the needed power of the uplink channels of relatively low priorities into account, not only power may be allocated for uplink channels of high priorities, but also uplink channels of low priorities may be transmitted punctually, thereby further improving overall performance of uplink information transmission. 
     Embodiment 3 
     An embodiment of the present disclosure provides a communication system.  FIG. 13  is a schematic diagram of a structure of the communication system of The embodiment of the present disclosure. As shown in  FIG. 13 , the communication system  1300  includes a first base station  1301 , a second base station  1302  and a UE  1303 . The first base station or the second base station may be a macro base station, or a small base station, etc., and the present disclosure is not limited thereto. 
     The UE  1303  keeps in connection with at least two cells formed by the first base station  1301  and the second base station  1302 , and is configured to sort priorities of uplink channels of the at least two cells when transmitting signals of the uplink channels containing uplink control information for the at least two cells within the same subframe, and allocate power for the uplink channels of the at least two cells according to a result of priority sorting; when allocating power for an uplink channel, needed power of one or more uplink channels with lower priorities than that of the uplink channel is taken into account. 
     An embodiment of the present disclosure further provides a computer-readable program, when the program is executed in a UE, the program enables the UE to carry out the method for controlling power of an uplink channel as described in Embodiment 1. 
     An embodiment of the present disclosure further provides a storage medium in which a computer-readable program is stored, the computer-readable program enables a UE to carry out the method for controlling power of an uplink channel as described in Embodiment 1. 
     The above apparatuses and methods of the present disclosure may be implemented by hardware, or by hardware in combination with software. The present disclosure relates to such a computer-readable program that when the program is executed by a logic device, the logic device is enabled to carry out the apparatus or components as described above, or to carry out the methods or steps as described above. The present disclosure also relates to a storage medium for storing the above program, such as a hard disk, a floppy disk, a CD, a DVD, and a flash memory, etc. 
     One or more functional blocks and/or one or more combinations of the functional blocks in Figures may be realized as a universal processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware component or any appropriate combinations thereof. And they may also be realized as a combination of computing equipment, such as a combination of a DSP and a microprocessor, multiple processors, one or more microprocessors in communication combination with a DSP, or any other such configuration. 
     The present disclosure is described above with reference to particular embodiments. However, it should be understood by those skilled in the art that such a description is illustrative only, and not intended to limit the protection scope of the present disclosure. Various variants and modifications may be made by those skilled in the art according to the principle of the present disclosure, and such variants and modifications fall within the scope of the present disclosure.