SYSTEM AND METHOD FOR ENLARGING AMPLITUDE MINIMA IN A LINEAR MODULATION SIGNAL

摘要

A system and a method to enlarge the minimum signal of a linear modulation signal (115) including multi-carrier modulation, such as Scalable advanced Modulation or Orthogonal Frequency Division Multiplexing, are disclosed. A minimum enlarger (120) exploits a simple amplitude limiter (220) so as not to interfere with an existing peak suppression scheme. The amplitude limiter (220) enlarges local minimum amplitude values to a predetermined minimum amplitude threshold if the local minimum amplitude values are less than the predetermined minimum amplitude threshold. While the amplitude limiter (220) adjusts the local minimum amplitude values in the linear modulation signal (115), the phase of the linear modulation signal (115) is maintained. The conditioned linear modulation signal (125) increases the efficiency of a linear power amplifier (130). The spectral change of the linear modulation signal due to the disclosed scheme is negligible because the adjusted signal power is negligible.