Patent ID: 8098451

Claim:
A system for determining fly height, the system comprising: a head assembly disposed in relation to a storage medium; a write channel; a read circuit, wherein the read circuit is operable to receive information from both the head assembly and the write channel; a frequency determination circuit, wherein the frequency determination circuit is operable to receive a first signal from the read circuit corresponding to information received from the write channel and to provide a first fundamental frequency and a first higher order frequency based on the first signal, and wherein the frequency determination circuit is operable to receive a second signal from the read circuit corresponding to information received from the head assembly and to provide a second fundamental frequency and a second higher order frequency based on the second signal; a compensation variable calculation module, wherein the compensation variable calculation module is operable to divide the first fundamental frequency by the first higher order harmonic to yield a compensation variable; and a fly height calculation module, wherein the fly height calculation module is operable to divide the second fundamental frequency by the second higher order harmonic and the compensation variable to yield an indication of a distance between the head assembly and the storage medium.