通信技术
通信技術
통신기술
COMMUNICATIONS TECHNOLOGY
2014年
1期
29-32
,共4页
Turbo码%不等保护%已知比特%关键比特
Turbo碼%不等保護%已知比特%關鍵比特
Turbo마%불등보호%이지비특%관건비특
turbo code%unequal protection%known bits%key bits
交织器的引入使Turbo码对不同信息位具有明显的不等保护特性，从而对其性能产生影响。为了提高Turbo码译码性能，在给定的S距离伪随机交织器下，首先通过对多组随机输入信息序列的位误比特率仿真分析，找到对Turbo码性能影响较大的关键比特位置，然后在对Turbo码不等保护特性和已知比特Turbo码进行理论分析和研究的基础上，提出了关键比特不等保护和结合已知比特的Turbo码不等保护两种方案。最后，对提出的方案进行了仿真验证，结果表明在交织长度分别为200和400两种条件下，两种保护方案在高信噪比时与未保护相比均有0.2 dB以上增益，且结合已知比特的Turbo码不等保护方案比关键比特保护方案性能更优。
交織器的引入使Turbo碼對不同信息位具有明顯的不等保護特性，從而對其性能產生影響。為瞭提高Turbo碼譯碼性能，在給定的S距離偽隨機交織器下，首先通過對多組隨機輸入信息序列的位誤比特率倣真分析，找到對Turbo碼性能影響較大的關鍵比特位置，然後在對Turbo碼不等保護特性和已知比特Turbo碼進行理論分析和研究的基礎上，提齣瞭關鍵比特不等保護和結閤已知比特的Turbo碼不等保護兩種方案。最後，對提齣的方案進行瞭倣真驗證，結果錶明在交織長度分彆為200和400兩種條件下，兩種保護方案在高信譟比時與未保護相比均有0.2 dB以上增益，且結閤已知比特的Turbo碼不等保護方案比關鍵比特保護方案性能更優。
교직기적인입사Turbo마대불동신식위구유명현적불등보호특성，종이대기성능산생영향。위료제고Turbo마역마성능，재급정적S거리위수궤교직기하，수선통과대다조수궤수입신식서렬적위오비특솔방진분석，조도대Turbo마성능영향교대적관건비특위치，연후재대Turbo마불등보호특성화이지비특Turbo마진행이론분석화연구적기출상，제출료관건비특불등보호화결합이지비특적Turbo마불등보호량충방안。최후，대제출적방안진행료방진험증，결과표명재교직장도분별위200화400량충조건하，량충보호방안재고신조비시여미보호상비균유0.2 dB이상증익，차결합이지비특적Turbo마불등보호방안비관건비특보호방안성능경우。
The introduction of interleaver makes the Turbo code have the obvious unequal protection of differ-ent information bits,thus limiting the performance of turbo code. In order to improve the performance of Tur-bo code,and under certain condition of given S-random interleaver,the key bits which may seriously impact the performance of Turbo code could be searched out through simulation and analysis on the bit error rate of input information sequences. Based on analysis and research of the unequal protection and KB ( known-bits) turbo code,the two protection schemes,including the key-bit protection and the known-bit protection, are proposed. Finally,the simulation indicates that with the different interleaving lengths of 200 and 400,the proposed schemes both could have more than 0. 2dB SNR gain under the condition of high SNR,while the known-bit protection scheme could acquire even better performance than the key-bit protection scheme.
