The present invention is a synthetic speech encoding device that produces
a synthetic speech signal which closely matches an actual speech signal.
The actual speech signal is digitized, and excitation pulses are selected
by minimizing the error between the actual and synthetic speech signals.
The preferred pattern of excitation pulses needed to produce the
synthetic speech signal is obtained by using an excitation pattern
containing a multiplicity of weighted pulses at timed positions. The
selection of the location and amplitude of each excitation pulse is
obtained by minimizing an error criterion between the synthetic speech
signal and the actual speech signal. The error criterion function
incorporates a perceptual weighting filter which shapes the error
spectrum.