c=phaseunlockreal(c,a,M);
phaseunlockreal(c,a,M) removes phase locking from the Gabor coefficients c. The coefficient must have been obtained from a dgtreal with parameter a and using the 'timeinv' flag.
Phase locking the coefficients modifies them so as if they were obtained from a frequency-invariant Gabor system. A filter bank produces phase locked coefficients.
M. Puckette. Phase-locked vocoder. Applications of Signal Processing to Audio and Acoustics, 1995., IEEE ASSP Workshop on, pages 222 --225, 1995.