Blind dereverberation of sinusoid signals using PLL-based combined phase and amplitude analysis

In this paper a new `blind´ single-microphone method for the dereverberation of sinusoid signals is presented. A phase-locked-loop is utilized to precisely track the amplitude, frequency and phase offset of a reverberated recording. This information can then be combined to calculate the amplitude and phase offset of single reverberated wavefronts, which allows to subtract them from the original recording. Experimental results have shown that the direct-to-reverberant ratio of recordings can be improved to an extent equal to a delay-and-sum beamformer with 5 microphones. At the end, extensions are outlined which might make the method suitable for dereverberation of real speech.