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  • 學位論文

基於適應性網路模糊推論系統應用於區域多點分配服務系統之相容碼率打孔渦輪碼

ANFIS-based rate compatible punctured turbo codes for LMDS system

指導教授 : 蔡木金
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摘要


LMDS系統可以滿足大部分的都市、小家庭以及大型企業用戶中所需求之語音、多媒體及數據傳輸等多樣化寬頻服務。然而,最主要影響LMDS系統的服務品質因素為雨衰及細胞內干擾。 為了減少LMDS系統中雨衰和細胞內干擾的問題,我們提出新的標準由雨衰之影響來選擇打孔模式,進而改善LMDS系統的效能。根據系統的環境,使用關於雨衰的參數來調整碼率減少冗餘位元和改進傳送率。模擬結果顯示出,在區域多點分配服務系統中,使用適應性網路模糊推論系統之相容碼率打孔渦輪碼,相較於沒有打孔的渦輪碼傳送模式中,在相似的位元錯誤率之下提升了較高的傳送率。

並列摘要


LMDS systems to meet most of the city, family and large enterprise customers by the demand of diversification of broadband services, such as voice, multimedia and data transmission. However, rain attenuation and inter cell interference (ICI) influence are the main factors affecting the Quality of Service (QoS) in LMDS system. In order to reduce the impact of rain attenuation and inter cell interference in LMDS system, we propose a new criterion that can choice the puncturing patterns from the impact of rain fade, lead to improve the performance of LMDS system. According to the channel condition, we can use the parameter about rain fade to adjust the code rate which reducing the redundancy bit and improve the throughput. Simulation results show the performance with and without ANFIS (adaptive network fuzzy inference system) based rate compatible punctured turbo code in a similar BER conditions, the former upgrade a higher throughput.

參考文獻


[5] B Papazian Peter., George A. Hufford, Robert J. Achatz and Randy Hoffman, “Study of the Local Multipoint Distribution Service Radio Channel,” IEEE Transactions on Broadcasting, Vol. 43, No. 2, June 1997.
[6] Chih-Yuan Chu and K.S. Chen, "Effects of Rain Fading on the Efficiency of the Ka-band LMDS System in the Taiwan Area," IEEE Transactions on vehicular technology, January 2005.
[7] Joachim Hagenauer, Peter Hoeher, "A Viterbi Algorithm with Soft-Decision Output and its Applications," IEEE 1989.
[9] R. Bose, G. Bauer, A. Hayn, R. Jakoby” LOS and NLOS interference investigations for LMDS network,” Dept. of EE., IIT Delhi, Hauz Khas, 110016.
[10] C.H. Lee, B.Y. Chung, and S.H. Lee, Dynamic modulation scheme in consideration of cell interference for LMDS, Proc. Int. Conf. Commun. Tech., (1998), S38-8-1 – S38-8-5.

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