摘要
为缩短数字视频广播卫星标准(DVB-S)接收系统中内码信息的估计时间,提出了两套解决方案.方案一:根据维持比译码过程中,从当前时刻回溯到译码深度以前时刻的各条幸存路径基本重合的原理进行判定;方案二:利用"二次编码"的特性,对译码数据进行再编码,并采用置信度结合有限状态机构成的判定机制,加快了估计过程.经过仿真发现,方案一虽然能在很大程度上缩短估计时间,但可靠性受到信道条件和译码深度的限制;而方案二不仅缩短了估计时间,而且避免了方案一所受到的限制,保证了估计过程的可靠性,因此方案二具有可行性.
In order to reduce the estimate-time of the inner-code information in DVB-S receive systems,two solutions were put forward.Solution I:According to the principle that the survival-paths tracing back to the decode-depth beforetime are almost converged in the viterbi decoding process,the estimation deci-sion was made;Solution II:Taking advantage of the property of'Secondary Encode',the decision mecha-nism with confidence levels was applied and Finite State Machine structure was adopted.The simulation results showed that the estimate-time of Solution I was reduced remarkably,but the reliability of estima-tion was limited by the channel condition and the decode-depth;Solution II not only reduced the estimate- time,but also avoided the limitations met in Solution I.So the reliability of the estimating process is guar-anteed in Solution II and Solution II is feasible.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2004年第5期549-553,共5页
Journal of Zhejiang University：Engineering Science
