Cross product enhanced harmonic transposition

Abstract

The present invention relates to audio coding systems which make use of a harmonic transposition method for high frequency reconstruction (HFR). A system and a method for generating (303) a high frequency component of a signal from a low frequency component of the signal is described. The system comprises an analysis filter bank (301) providing a plurality of analysis subband signals of the low frequency component of the signal. It also comprises a non-linear processing unit (302) to generate a synthesis subband signal (803) with a synthesis frequency by modifying the phase of a first (801) and a second (802) of the plurality of analysis subband signals and by combining the phase-modified analysis subband signals. Finally, it comprises a synthesis filter bank (302) for generating the high frequency component of the signal from the synthesis subband signal. (Figure 8)