Improving multipulse coding for low bit-rate speech communications

Multipulse excited linear predictive coding (MPELPC) is a good medium bit-rate speech coding technique. However, due to the enormous processing required for searching the pulse information (pulse positions and amplitudes), many practical implementations of multipulse coders actually utilize some simplified pulse search algorithms such as dropping the amplitude optimization during the search for the pulse positions. Also, for ease of coding the pulse positions, small search frame sizes are usually used. These simplifications would degrade the speech quality significantly.