State analysis and optimization of time-varying systems via Haar wavelets a
re proposed in this paper. Based upon some useful properties of Haar functi
ons, a special product matrix and a related coefficient matrix are applied
to solve the time-varying systems first. Then the backward integration is i
ntroduced to solve the adjoint equation of optimization. The unknown Haar c
oefficient matrix will be in generalized Lyapunov equation form, which is s
olved via a single-term algorithm. The local property of Haar wavelets is f
ully applied to shorten the calculation process. A brief comparison between
Haar wavelet and other orthogonal functions is also given. Copyright (C) 1
998 John Wiley & Sons, Ltd.