Narrow-band interference excision in spread-spectrum systems using new N-sigma algorithm based on fuzzy threshold  

作　　者：Feng Jining Wu Siliang Wang Ju 

机构地区：[1]Dept. of Electronic Engineering, Beijing Inst. of Technology, Beijing 100081, P. R. China [2]Dept. of Electronic Engineering, Hebei Normal Univ., Shijiazhuang 050031, P. R. China

出　　处：《Journal of Systems Engineering and Electronics》2009年第1期20-26,共7页系统工程与电子技术（英文版）

摘　　要：The key to narrow-band interference excision in frequency domain is to determine the excision thresh- old in direct-sequence spread-spectrum （DS-SS） systems. The excision threshold is a non-linear function related to the number and the power of interference, and attempting to get the exact relation of threshold related to the number and the power of interference is almost impossible. The N-sigma algorithm determines the excision threshold using subsection function; however, the excision threshold determined by this method is not exact. A new method to determine the threshold of N-sigma algorithm is proposed. The new method modifies the scale factor N by use of the membership function. The threshold determined by this method is consecutive and smooth, and it is closer to the fact than that of the initial N-sigma algorithm. The GPS signal and single-tone （CW） interference （that is, typical narrow-band interference） are implemented in the simulation, and the results are presented to demonstrate the validity of the new algorithm.The key to narrow-band interference excision in frequency domain is to determine the excision thresh- old in direct-sequence spread-spectrum （DS-SS） systems. The excision threshold is a non-linear function related to the number and the power of interference, and attempting to get the exact relation of threshold related to the number and the power of interference is almost impossible. The N-sigma algorithm determines the excision threshold using subsection function; however, the excision threshold determined by this method is not exact. A new method to determine the threshold of N-sigma algorithm is proposed. The new method modifies the scale factor N by use of the membership function. The threshold determined by this method is consecutive and smooth, and it is closer to the fact than that of the initial N-sigma algorithm. The GPS signal and single-tone （CW） interference （that is, typical narrow-band interference） are implemented in the simulation, and the results are presented to demonstrate the validity of the new algorithm.

关 键 词：direct-sequence spread-spectrum systems adaptive frequency domain interference suppression fuzzyfunction GPS signal. 

分 类 号：TN914.42[电子电信—通信与信息系统] TS255.7[电子电信—信息与通信工程]