| 摘要 |
The present invention relates to an apparatus (100), a base station (500) and a method for reducing peak power of an input signal (1) using successive processing stages (10). Each stage (10) comprises a peak finder (11) arranged to find at least one peak of the input signal (1) exceeding a threshold level, and to make a list (LO) comprising information on a number of the highest peaks or information on each peak; a peak selector (12) adapted to receive the list (LO) and to receive, from each preceding stage (10), a list (Li) with information on unreduced peaks and the stage number. The peak selector (12) further selects from all lists a peak (P) to be reduced and determines a fractional sample shift value (FSi) of the stage in which the selected peak was found. Each stage (10) further comprises a kernel selector that selects a kernel signal (Ki) that is fractionally sample shifted with the sum of all fractional shift values, starting from the shift value (FSi) up to the present stage. Each stage (10) also comprises a kernel manipulator (14) that manipulates the selected kernel signal based on information on the selected peak (P). Each stage (10) further comprises a combiner (15) that reduces the selected peak (P) by combining the manipulated kernel signal with a delayed version of the input signal (1). |
