A 4.2 KB S LOW-DELAY SPEECH CODER WITH MODIFIED CELP/

In this letter, we propose a low-delay speech coder at 4.2 kb/s. In th e proposed coder, we remove short-term prediction and use three-tap lo ng term prediction to exploit the speech redundancy, A ''dual-decision '' pitch estimation algorithm and an adaptive sinusoidal excitation co debook are introduced to improve the performance of the proposed coder , The synthesized speech of this coder has comparable quality to that of conventional CELP coders at similar bit rates, while it has a codin g delay of only 5 ms.