Resolution limits of timing-based servo schemes in magnetic tape drives

In this work, we evaluate a set of experimental TBS patterns servo-formatted on a perpendicular barium-ferrite (BaFe) tape medium and quantify the achievable resolution in the lateral position estimate. We compare closed-loop position error measurements with resolution estimates based on a) the noise floor of the power spectral density of the lateral tape motion measured from the servo pattern during closed-loop track-following, and b) an analytical lower bound which depends on the servo readback signal shape and the signal-to-noise ratio.