On impulse response measurement techniques for linear tape recording channels

Abstract

We apply Golay (1961) complementary sequences for measuring the impulse response and the amplitude and phase transfer functions of a linear magnetic tape recording channel. Our experimental channel suffers from nonlinear distortion caused by a magnetoresistive sensor. The measured characteristics, in particular the amplitude transfer function, show a better performance than the same characteristics obtained with the de facto standard impulse response measurement technique using feedback shift register sequences. Based on a practical nonlinear Volterra model of our experimental tape recording channel, we analyze the artefacts due to second and third order nonlinear distortion which can occur in the Golay impulse responses and transfer functions.