Method and arrangement in a cellular communications system

Abstract

A method of controlling transmission output power in a cellular telecommunications network includes setting. a pre-defined power mask for at least one of a sub-frame and an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a signal transmission. The power mask is defined by at least one parameter. The method further includes adapting at least one of the at least one power mask parameter of the power mask to a signal transmission characteristic of the signal transmission and applying the adapted power mask to at least one of the sub-frame and the OFDM symbol.

1 . A method of controlling transmission output power in a cellular telecommunications network comprising:
 setting a pre-defined power mask for at least one of a sub-frame and an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a signal transmission, wherein the power mask is defined by at least one parameter associated with any of the following: a starting point of a first power ramp, an ending point of the first power ramp, a starting point of a second power ramp, an ending point of the second power ramp, a first and second duration of the first and second power ramps, respectively, and a first and second power level at a specific time of the first and second power ramps, respectively;   adapting at least one of the at least one power mask parameter of the power mask to a signal transmission characteristic of the signal transmission; and   applying the adapted power mask to at least one of the sub-frame and the OFDM symbol.   
     
     
         2 . The method of  claim 1 , wherein the method is implemented in a user equipment. 
     
     
         3 . The method of  claim 2 , further comprising receiving an instruction indicating how to adapt the at least one of the at least one power mask parameter from a network node. 
     
     
         4 . The method of  claim 3 , wherein the instruction comprises an identity of one out of a plurality of standardized power masks. 
     
     
         5 . The method of  claim 1 , wherein the method is implemented in a network node. 
     
     
         6 . The method according to  claim 1 , wherein adapting the power mask parameter comprises adjusting the ending point parameter of the second power ramp to be placed inside said sub-frame when a successive sub-frame of said sub-frame contains data. 
     
     
         7 . The method of  claim 1 , wherein adapting the power mask parameter comprises adjusting the starting point parameter of the second power ramp to be placed outside said sub-frame when a successive sub-frame of said sub-frame does not contain data. 
     
     
         8 . The method of  claim 1 , wherein adapting the power mask parameter comprises:
 adjusting the starting point parameter of the second power ramp to be placed inside said sub-frame;   adjusting the ending point parameter of the second power ramp to be placed outside said sub-frame; and   shortening the duration of the second power ramp when said sub-frame contains data and a successive sub-frame of said sub-frame contains data.   
     
     
         9 . The method of Clam  1 , wherein adapting the power mask parameter comprises:
 adjusting the ending point parameter of the first power ramp to be placed outside said OFDM symbol; and   adjusting the starting point parameter of the second power ramp to be placed outside said OFDM symbol when said OFDM symbol contains a reference signal.   
     
     
         10 . The method of  claim 1 , wherein:
 the OFDM symbol comprises a first OFDM symbol; and   adapting the power mask parameter comprises adjusting the starting point parameter of the first power ramp to be placed inside the first OFDM symbol when a second OFDM symbol preceding the first OFDM symbol contains a reference signal.   
     
     
         11 . The method of  claim 1 , wherein:
 the OFDM symbol comprises a first OFDM symbol; and   adapting the power mask parameter comprises adjusting the ending point parameter of the second power ramp to be placed inside said first OFDM symbol when a second OFDM symbol succeeding the first OFDM symbol contains a reference signal.   
     
     
         12 . The method of  claim 1 , wherein:
 the sub-frame comprises a first sub-frame; and   adapting the power mask parameter comprises adjusting the ending point parameter of the second power ramp to be placed inside the first sub-frame when a second sub-frame succeeding the first sub-frame contains data with high order modulation.   
     
     
         13 . The method of  claim 1 , wherein:
 the sub-frame comprises a first sub-frame; and   adapting the power mask parameter comprises adjusting the starting point parameter of the second power ramp to be placed outside the first sub-frame when a second sub-frame succeeding the first sub-frame contains data with low order modulation.   
     
     
         14 . The method of  claim 1 , wherein adapting the power mask parameter comprises:
 adjusting the ending point parameter of the first power ramp to be placed outside said sub-frame; and   adjusting the starting point parameter of the second power ramp to be placed outside said sub-frame when a signal disturbance is lower or equal to a pre-determined threshold value.   
     
     
         15 . The method of  claim 1 , wherein adapting the power mask parameter comprises:
 adjusting the starting point parameter of the first power ramp to be placed inside said sub-frame; and   adjusting the ending point parameter of the second power ramp to be placed inside said sub-frame when a signal disturbance is greater than a pre-determined threshold value.   
     
     
         16 . An apparatus for controlling transmission output power in a cellular telecommunications network, the apparatus comprising:
 a processor configured to:
 set a pre-defined power mask for at least one of a sub-frame and an Orthogonal Frequency-Division Multiplexing (OFDM) symbol of a signal transmission, wherein the power mask is defined by at least one parameter associated with any of the following: a starting point of a first power ramp, an ending point of the first power ramp, a starting point of a second power ramp, an ending point of the second power ramp, a first and second duration of the first and second power ramps, respectively, and a first and second power level at a specific time of the first and second power ramps, respectively; 
 adapt at least one of the at least one power mask parameter of the power mask to a signal transmission characteristic of the signal transmission; and 
 apply the adapted power mask to at least one of the sub-frame and the OFDM symbol. 
   
     
     
         17 . The apparatus of  claim 16 , wherein the apparatus comprises a user equipment. 
     
     
         18 . The apparatus of  claim 17 , further comprising a receiver configured to receive an instruction indicating how to adapt the at least one of the at least one power mask parameter from a network node. 
     
     
         19 . The apparatus of  claim 18 , wherein the instruction comprises an identity of one out of a plurality of standardized power masks. 
     
     
         20 . The apparatus of  claim 16 , wherein the apparatus comprises a network node. 
     
     
         21 . The apparatus of  claim 16 , wherein the processor is configured to adapt. the power mask parameter by adjusting the ending point parameter of the second power ramp to be placed inside said sub-frame when a successive sub-frame of said sub-frame contains data. 
     
     
         22 . The apparatus of  claim 16 , wherein the processor is configured to adapt the power mask parameter by adjusting the starting point parameter of the second power ramp to be placed outside said sub-frame when a successive sub-frame of said sub-frame does not contain data. 
     
     
         23 . The apparatus of  claim 16 , wherein the processor is configured to adapt the power mask parameter by:
 adjusting the starting point parameter of the second power ramp to be placed inside said sub-frame;   adjusting the ending point parameter of the second power ramp to be placed outside said sub-frame; and   shortening the duration of the second power ramp when said sub-frame contains data and a successive sub-frame of said sub-frame contains data.   
     
     
         24 . The apparatus of  claim 16 , wherein the processor is configured to adapt the power mask parameter by:
 adjusting the ending point parameter of the first power ramp to be placed outside said OFDM symbol; and   adjusting the starting point parameter of the second power ramp to be placed outside said OFDM symbol when said OFDM symbol contains a reference signal.   
     
     
         25 . The apparatus of  claim 16 , wherein:
 the OFDM symbol comprises a first OFDM symbol, and   the processor is configured to adapt the power mask parameter by adjusting the starting point parameter of the first power ramp to be placed inside the first OFDM symbol when a second OFDM symbol preceding the first OFDM symbol contains a reference signal.   
     
     
         26 . The apparatus of  claim 16 , wherein:
 the OFDM symbol comprises a first OFDM symbol; and   the processor is configured to adapt the power mask parameter by adjusting the ending point parameter of the second power ramp to be placed inside said first OFDM symbol when a second OFDM symbol succeeding the first OFDM symbol contains a reference signal.   
     
     
         27 . The apparatus of  claim 16 , wherein:
 the sub-frame comprises a first sub-frame; and   wherein the processor is configured to adapt the power mask parameter by adjusting the ending point parameter of the second power ramp to be placed inside the first sub-frame when a second sub-frame succeeding the first sub-frame contains data with high order modulation.   
     
     
         28 . The apparatus of  claim 16 , wherein:
 the sub-frame comprises a first sub-frame; and   the processor is configured to adapt the power mask parameter by adjusting the starting point parameter of the second power ramp to be placed outside the first sub-frame when a second sub-frame succeeding the first sub-frame contains data with low order modulation.   
     
     
         29 . The apparatus of  claim 16 , wherein the processor is configured to adapt the power mask parameter by:
 adjusting the ending point parameter of the first power ramp to be placed outside said sub-frame; and   adjusting the starting point parameter of the second power ramp to be placed outside said sub-frame when a signal disturbance is lower or equal to a pre-determined threshold value.   
     
     
         30 . The apparatus of  claim 16 , wherein the processor is configured to adapt the power mask parameter by:
 adjusting the starting point parameter of the first power ramp to be placed inside said sub-frame; and   adjusting the ending point parameter of the second power ramp to be placed inside said sub-frame when a signal disturbance is greater than a pre-determined threshold value.