Patent ID: 7139142

Claim:
A magnetic tape drive comprising: at least one read head; a drive system for moving a magnetic tape with respect to said at least one read head such that said at least one read head may detect magnetic signals on said magnetic tape; a signal sampler for digitally sampling magnetic signals detected by said at least one read head, providing digital samples of said magnetic signals; and a signal quality system for extracting from said digital samples of a format required signal of said magnetic signals, an estimated amplitude of write equalization transitions of said format required signal; and for comparing said extracted estimated amplitude to acceptable amplitude; wherein said signal quality system for extracting said estimated amplitude, additionally for constructing a synthetic pulse representing a least squares fit to said digital samples, where one of the fitting criteria is the amplitude of said write equalization transitions; wherein said signal quality system additionally for constructing said synthetic pulse conducting a multi-dimensional minimization of mean squared error between said synthetic pulse and said digital samples. one of said multi-dimensions comprising said amplitude of said write equalization transitions; wherein said signal quality system additionally for constructing said synthetic pulse convolving a quasi-Lorentizian pulse of pulsewidth “a” and exponent “e”, with a sequence of signed NRZI transitions corresponding to a binary sequence of said format required signal having write equalization transitions.