摘要
在弱信号、遮挡等恶劣环境下,低载噪比的导航电文中含有大量的误码,常用的编码技术不能有效地纠正子帧中多比特位上的误码。本文提出了一种冗余法误码纠错方法,该方法依据少数服从多数的判别准则,选取不同数目的子帧样本,对同组子帧样本的各帧上相同比特位上的码元逐一进行比对的试验方式进行纠错试验。分析了不同载噪比、不同子帧样本数条件下进行冗余法纠错能够将各子帧中全部误码正确纠正的概率,例如,在子帧样本数为5,载噪比30dBHz时,整个子帧上的误码被全部纠正的概率高达96.64%时,纠错处理后的误码率比理论误码率降低2个数量级。
In weak signal,blocking and other harsh environment,the low SNR navigation message contains a lot of error codes;Normal code technology cannot effectively correct the errors more than one bit in the frame.This paper proposes a redundancy method of error correction.The method that relies on the rule which is the minority obey to the majority chooses different number of frames and compare the code in the same bit of one frame in the frame samples.Under different signal noise rate,this paper analyses the probability of all errors corrected by the redundancy method under different number of frame samples and the effect of depressing the error rate.For example,when the number of frame samples is 5 and the SNR is 30dBHz,the rate of all error codes in one frame corrected is up to 96.64% and the SNR is about 1% of the original one after the redundancy method.
出处
《全球定位系统》
CSCD
2015年第2期31-35,47,共6页
Gnss World of China
关键词
弱信号
低载噪比
误码
冗余纠错
Weak signal
low SNR
error codes
redundancy error correction
