Title :
Direct-sequence spread spectrum narrowband interference rejection using property restoration
Author :
Doherty, John F. ; Stark, Henry
Author_Institution :
Dept. of Electr. & Comput. Eng., Iowa State Univ., Ames, IA, USA
fDate :
9/1/1996 12:00:00 AM
Abstract :
A new method of rejecting narrowband interference in direct-sequence spread spectrum (DS/SS) communications is presented. A typical approach is to reject the interference using a filter with large attenuation at the interference frequencies before despreading. The interference rejection method presented incorporates vector space projection techniques to suppress the correlated interference. Several signal characteristics are formulated which lead to constraint surfaces in the vector space of possible solutions. These constraint surfaces describe interference rejection solutions which introduce minimal distortion to the spread spectrum signal and simultaneously remove the interference. The constraint surfaces essentially correspond to spread spectrum signal estimates which, after interference rejection, conform to known characteristics of the transmitted spread spectrum signal. The formulation of the surfaces relies on prior knowledge about the spread spectrum signal correlation and spectral properties
Keywords :
correlation methods; interference suppression; pseudonoise codes; radiofrequency interference; signal restoration; spectral analysis; spread spectrum communication; DS/SS communications; attenuation; constraint surfaces; correlated interference; direct-sequence spread spectrum; filter; interference frequencies; narrowband interference rejection; property restoration; signal characteristics; spectral properties; spread spectrum signal correlation; spread spectrum signal estimates; vector space; vector space projection techniques; Adaptive filters; Distortion; Image restoration; Interference constraints; Interference suppression; Narrowband; Signal processing; Signal processing algorithms; Signal restoration; Spread spectrum communication;
Journal_Title :
Communications, IEEE Transactions on