서지주요정보
전송률 변환이 고려된 AMR과 13kbps Qcelp의 tandem없는 상호 부호화기 = Tandemless transcoder between AMR and 13kbps Qcelp with rate adaptation
서명 / 저자 전송률 변환이 고려된 AMR과 13kbps Qcelp의 tandem없는 상호 부호화기 = Tandemless transcoder between AMR and 13kbps Qcelp with rate adaptation / 김희만.
저자명 김희만 ; Kim, Hee-Man
발행사항 [대전 : 한국과학기술원, 2004].
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소장정보

등록번호

8015153

소장위치/청구기호

학술문화관(문화관) 보존서고

MEE 04001

SMS전송

도서상태

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반납예정일

초록정보

This thesis gives the description of transcoder for Tandemless Operation between AMR and 13kbps Qcelp which are the standard speech coder of IMT-2000 services. A simple solution for the compatibility problem between two different coding standards is obtained by the Tandem Operation (TO). The tandem operation generates a speech signal by using a decoder from one standard and then encodes again the signal by the other standard. Therefore the speech signal undergoes encoding decoding process twice and these results in quality loss and extra delay. To avoid these degradations, Tandem Free Operation (TFO) is used in some mobile networks. TFO passes speech-encoded packet from one Mobile station (MS) to Another MS without generating intermediate PCM through a gateway. But, TFO properly works only when two MS has a same speech coder. These problems can be reduced by the Transcoder for Tandemless Operation (TLO). Transcoder for TLO directly converts the speech packet from one to the other coder. Whereas the packet conversions are performed in parameter domain, we can get less degraded speech with TLO than speech with TO. The proposed transcoding algorithm for TLO is composed of two main parts: (1) speech parameter conversions of LSP, Pitch, Codebook, (2) rate adaptation from one to another coder. The proposed algorithm reduces total delay and loss of quality in end-to-end mobile communication. Objective quality evaluation confirmed that the proposed algorithm introduces less degraded speech compared to TO.

서지기타정보

서지기타정보
청구기호 {MEE 04001
형태사항 vi, 48 p. : 삽도 ; 26 cm
언어 한국어
일반주기 저자명의 영문표기 : Hee-Man Kim
지도교수의 한글표기 : 이황수
지도교수의 영문표기 : Hwang-Soo Lee
학위논문 학위논문(석사) - 한국과학기술원 : 전기및전자공학전공,
서지주기 참고문헌 : p. 47-48
주제 상호부호화기
전송률 변환
TRANSCODER
RATE ADAPTATION
QCELP
AMR
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