Process for improving the determination of the sir target in an outer loop power control mechanism of umts ue

A process for performing an Outer Loop power control in an User Equipment for a UMTS telecommunication system comprising a first process of:

• applying a first estimation of the Signal to Interference (SIR) target (SIRtarg) in accordance with a value of a Block Error Rate (BLER) target received from a base station comprising:
• receiving the BLER target (BLERtarg) from the base station;
• performing an estimation of the BLER value (BLERest) on a number of N1 blocks;
• comparing the BLERest to the value of the BLERtarg and in response to the comparison, increasing said SIRtarg when BLERest>BLERtarg and decreasing the SIRtarg when BLERest<BLERtarg;
• and
• a second process in parallel with the first process, the second process comprising:
• correcting the value of the SIRtarg issued by the first process, comprising of the steps of:
• computing an estimation of the SIR value;
• counting a number of CRC errors occurring during a predefined sliding window;
• detecting a double condition comprising:
• detecting a burst of CRC errors occurring during the predefined sliding window;
• monitoring for a pre-convergence of the first estimation of the SIRtarg, said pre-convergence being when estimation of the SIR value is substantially close to the SIRtarg value issued by said first estimation of the SIRtarg;
• and
• applying an immediate correction to said SIRtarg.

A receiver for an UMTS telecommunication system comprising an outer loop power control mechanism adapted to:

• apply a first estimation of a Signal To Interference (SIRtarg) in accordance with the value of a Block Error Rate target (BLERtarg) received from a base station;
• receive the BLERtarg from the base station;
• perform an estimation of the BLER value (BLERest) on a number of N1 blocks;
• compare the BLERest to the BLERtarg and increase the SIRtarg when BLERest>BLERtarg and decrease the SIRtarg when the BLERest<BLERtarg;
• the outer loop control mechanism adapted to simultaneously:
• compute an estimation of the SIR value;
• count a number of CRC errors occurring during a predefined sliding window;
• detect a double condition comprising:
• a burst of CRC errors occurring during the predefined sliding window;
• monitor for a pre-convergence of the first estimation of SIRtarg with the estimation of the SIR value;
• and
• apply an immediate correction to SIRtarg.