The Generation of all q - Markov Covers

Abshocr-ReeenHy developed model reduction pmcedurer lead (for the lower order model with the same Mo,. . . , M,-, and single input-ontput ease) to 9th degree systems * fa P M ~ V R,,. . ., R ~ ~ . such apprO-ation~ have been ;Ged qparametes and first q covariance parameters ( M d o v parameters of the causal paR of the power rpecbum) taking prerribed valWe paraMarkov covers (COVER = Covariance Equivalent Realimeterize the e l a s of 811 such swtems. par contimowiitm %stem the zation) in [71. Similar approximations appear in [91 for c las indudes an infinite set, &merear for discrete-time the d i s has only single input-output systems and in [lo] for the multitwo members. The result is i m w t in *hat it iUuJtrates the freedom input-output case. These derivations are much less direct available in a model reduction procedure. than ours and there is no attemDt in 191, I101 to char-