Title :
Interference rejection in DS/SS-systems with an improved RLS-whitening filter
Author :
SAARNISAARI, Harri
Author_Institution :
Telecommun. Lab., Oulu Univ., Finland
Abstract :
The Huber (1964) m-estimation principle is applied, in a simple way, to improve the interference mitigation capability of the recursive least squares (RLS) whitening interpolation filter, implemented either in the basic or linear phase form. The simulation results show that in the code phase estimation the robust linear phase RLS interpolation filter mitigates interference more than the regular RLS and linear phase RLS interpolation filters, especially if the bandwidth of the interference is narrow (<23%) when compared to the bandwidth of the direct sequence signal used. It is also shown that whitening does not significantly decrease the code phase estimation accuracy of the matched filter estimator
Keywords :
delay estimation; filtering theory; interference suppression; interpolation; least squares approximations; linear phase filters; matched filters; parameter estimation; phase estimation; radiofrequency interference; recursive estimation; spread spectrum communication; DS/SS-systems; Huber m-estimation; Huber postconditioning; RLS whitening interpolation filter; RLS-whitening filter; code phase estimation accuracy; delay estimator; direct sequence signal; interference bandwidth; interference rejection; linear phase RLS interpolation filter; linear phase filter; matched filter estimator; recursive least squares; simulation results; Bandwidth; Interference; Interpolation; Kalman filters; Lattices; Matched filters; Nonlinear filters; Phase estimation; Resonance light scattering; Robustness;
Conference_Titel :
Communications, 2001. ICC 2001. IEEE International Conference on
Conference_Location :
Helsinki
Print_ISBN :
0-7803-7097-1
DOI :
10.1109/ICC.2001.937115
