Turbo Trellis-Coded Modulation of EVRC Speech Encoder with Unequal Error Protection For Fading Channels
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چکیده
The Enhanced Variable Rate Codec (EVRC) is a standard for the “Speech Service Option 3 for Wideband Spread Spectrum Digital System,” which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigates the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power and bandwidth efficient coding scheme. The results show that UEP system outperforms the Equal Error Protection (EEP) one by 1.45 dB at BER of 5 10 − and the listening tests show that the quality of the decoded speech is better in UEP system compared to the EEP.
منابع مشابه
Turbo-Coded Modulation of EVRC Speech Encoder With Unequal Error Protection For Fading Channels
The Enhanced Variable Rate Codec (EVRC) is a standard for the “Speech Service Option 3 for Wideband Spread Spectrum Digital System,” which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigates the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power ...
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تاریخ انتشار 2003