窄頻MSK雙向通訊利用ILBC語音編碼和非均等錯誤保護通道編碼語音品質分析

An Analysis of Speech Quality of ILBC Vocoder by Using Unequal Error Protection (UEP) Code for Narrow Band MSK Two Way Radio

耿履冰(Lu-Ping Keng)

指導教授 ： 李世凱 ； 高永安

元智大學/電機通訊學院/通訊工程學系/碩士(2007年)

https://doi.org/10.6838/YZU.2007.00235

摘要

為了達到更佳的頻寬使用效率及保護通過有雜訊的通道之語音資料一直是無線傳輸系統重要的課題. iLBC(網際網路低速率語言編解碼器)目前被廣泛使用於在網際網路以傳輸語音. 本篇論文主要討論iLBC應用在北美ISM(industrial, scientific and medical. 工業,科學及醫療)頻帶, 利用MSK(minium shift key, 最小移頻鍵)作為窄頻道雙向無線通訊. 在模擬的系統中, 使用了數種不同的非均等誤碼保護(UEP, unequal error protection)策略來保護不同重要等級, 且通過AWGN (additive white Gaussian noise, 高斯雜訊通道)之iLBC資料. 最後, 利用”知覺語音評價”(PESQ, Perceptual Evaluation of Speech Quality)來量測語音的品質. 本論文顯示, 透過非均等誤碼保護法能夠提高PESQ的得分, 進而証明此系統可以比美傳統的FM雙向無線電.

關鍵字

網際網路低速率語言編解碼器 ； 非均等誤碼保護 ； 知覺語音評價 ； 最小移頻鍵 ； 雙向無線電 ； 迴旋碼 ； 工業及科學及醫療頻帶 ； 即時語音資料

並列摘要

To achieve more efficient usage of channel band width and provide better protection for the speech payload transmitted over lossy wireless transmission is an important topic in wireless communication system design. iLBC (internet low bit rate codec) is widely used in VOIP (voice over IP) application. This paper is concerned with use iLBC in narrow band MSK (minimum shift key) wireless transmission under north America ISM (industrial, scientific and medical) band. Simulation using different strategies of unequal error protection (UEP) scheme to protect different sensitive payload which passing through the AWGN (additive white Gaussian noise) channel. Finally, we utilize PESQ (Perceptual Evaluation of Speech Quality) to evalute the perceptual speech quality. The result is significant of improve PESQ scores in some strategies, and proof this system can compete traditional FM two way radio.

並列關鍵字

iLBC ； UEP ； PESQ ； MSK ； Two Way Radio ； Convolutional coding ； ISM Band ； Real Time Speech Data

參考文獻

[1] Goshi, J.; Ladner, R.; Mohr, A.; Riskin, E.; Lippman, A.; “Unequal loss protection for H.263 compressed video”. Data Compression Conference, 2003. Proceedings. DCC 2003 25-27 March 2003 Page(s):73 – 82.

[3] Yang, X.; Ce Zhu; Zheng Guo Li; Xiao Lin; Nam Ling; “An unequal packet loss resilience scheme for video over the Internet”. Multimedia, IEEE Transactions on

[4] Mohr, A.E.; Riskin, E.A.; Ladner, R.E.; “Unequal loss protection: graceful degradation of image quality over packet erasure channels through forward error correction”. Selected Areas in Communications, IEEE Journal on Volume 18, Issue 6, June 2000 Page(s):819 – 828.

[5] Wenwu Zhu.; Qian Zhang,; Ya-Qin Zhang,; “Network-adaptive rate control with unequal loss protection forscalable video over Internet”. Microsoft Res. China, Beijing; This paper appears in: Circuits and Systems, 2001. ISCAS 2001. The 2001 IEEE International Symposium. Publication Date: 2001. Volume: 5, On page(s): 109-112 vol. 5.

[6] Lianji Cheng; Wenjun Zhang; Li Chen; “Rate-distortion optimized unequal loss protection for FGS compressed video”. Broadcasting, IEEE Transactions on