Question

Which of the following codec is used by IS-136?

(a) Residual Excited Linear Predictive Coders

(b) Multipulse Excited LPC

(c) LPC Vocoders

(d) Vector sum excited LPC

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This intriguing question originated from Speech Codecs topic in division Speech Coding of Wireless/Mobile

Answer 1

Right option is (d) Vector sum excited LPC

The explanation: The US digital cellular system, IS-136 uses a vector sum excited linear predictive coder (VSELP). This coder operates at a raw data rate of 7950 bits/s and a total data rate of 13 kbps after channel coding.