Perceptual Evaluation of Speech Quality for ILBC Vocoder with Uneven Level Protection Over Narrow Band MSK Radio
Narrow band MSK (Minimum Shift Keying) radio is applied for high receiving sensitive wireless communications like "Walky-talky". iLBC (internet Low Bit-rate Codec) is widely used in VoIP (Voice over IP) applications like "Skype". This paper is concerned with the speech quality by using iLBC in narrow band MSK wireless communication. Several ULP (Uneven Level Protection) strategies to protect different part of iLBC coded payloads are evaluated under AWGN (Additive White Gaussian Noise). The authors utilize PESQ (Perceptual Evaluation of Speech Quality) to evaluate the perceptual speech quality. Simulation results show that significant improvement of PESQ scores are obtained by using appropriate ULP strategies so that their proposed MSK radio system can also achieve high receiving sensitivity.