Optimized loop filters in fixed WiMax PLL using LMI method

Achieving an optimal design of phase-locked loop (PLL) is a major challenge in WiMAX technology in order to improve system behavior against noise and to enhance Quality of Service (QoS). A new loop filter design method for PLL is introduced taking into consideration various design objectives such as small settling time, small overshoot and meeting Fixed WiMAX requirements. Optimizing conflicting objectives is accomplished using semi-Definite programming (especially Linear Matrix Inequality (LMI)) in conjunction with appropriate adjustment of certain design parameters. Infinite Impulse Response (IIR) and Finite Impulse Response (FIR), Digital filters are designed by Semi-Definite Programming (SDP) using SeDuMi (self-dual minimization) toolbox software. Design efficiency and performance of the proposed method are illustrated by simulations and comparisons to other design methods. Simulations showed that the IIR which was designed by SDP is better than the IIR which designed by Linear Programming (LP).Also, the FIR which was designed by SDP using SeDuMi software is better than the FIR which was designed in by SDP using CVX (convex optimization tool) software.

Autorentext

Dr. Hala J. El-Khozondar is an associate professor at EE at IUG of Gaza. She got her B.Sc. from BirZeit University in 1987. She had her Ph.D. from NMSU, USA in 1999. She is a senior member at ICTP. She is an awardee of Fulbright Scholarship, DAAD, AvH and Erasmus Mundus awards. Her interests include Wireless and optical communications.