Title :
Blind equalization of constant modulus signals using an adaptive observer approach
Author :
White, Langford B.
Author_Institution :
Signal Anal. Discipline, Commun. Div., Defence Sci. & Technol. Organ., Australia
fDate :
2/1/1996 12:00:00 AM
Abstract :
The paper addresses the problem of blind equalization of constant modulus signals which are degraded by frequency selective multipath propagation and additive white noise. An adaptive observer is used to update the weights of an FIR equalizer in order to restore the signal´s constant modulus property. The observer gain is selected using fake algebraic Riccati methods in order to guarantee local stability. The performance of this method is compared to the constant modulus algorithm for simulated FM-FDM signals and exhibits significantly better convergence properties, particularly for heavy-tailed noise
Keywords :
FIR filters; Riccati equations; adaptive equalisers; frequency division multiplexing; frequency modulation; multipath channels; radiofrequency interference; state estimation; FIR equalizer; adaptive observer approach; additive white noise; blind equalization; constant modulus signals; convergence properties; fake algebraic Riccati methods; frequency selective multipath propagation; heavy-tailed noise; local stability; observer gain; performance; simulated FM-FDM signals; Adaptive equalizers; Additive white noise; Blind equalizers; Convergence; Degradation; Finite impulse response filter; Frequency; Riccati equations; Signal restoration; Stability;
Journal_Title :
Communications, IEEE Transactions on