Characteristics of the readback signal in digital magnetic recording

Author

Nishikawa, Masaaki

Author_Institution

Nippon Telegraph and Telephone Public Corporation, Musashinoshi, Tokyo, Japan.

Volume

6

Issue

4

fYear

1970

fDate

12/1/1970 12:00:00 AM

Firstpage

811

Lastpage

817

Abstract

A theoretical treatment for the readback process in digital magnetic recording is presented. Three major factors, namely, the medium constant $s$ which defines the extent of the surface charge density, the head-to-medium spacing $d$ , and the read head gap $2 g,$ are taken into consideration. A general solution giving the characteristics of pulse readback signal is shown as a function of $s,d$ and $g$ . Both amplitude and pulse width of the readback signal are arranged as a product of the medium loss, spacing loss, and gap loss, making it easy to describe the influence of each factor separately. The final value of the amplitude and the pulse width is proportional to that of the recorded surface charge density. Spacing loss simply depends on the ratio of $d/s$ ; gap loss depends on the ratio of $g/(s + d)$ . Theoretical results are compared with experiments which show good agreement for a wide combination of $s,d$ , and $g$ .

Keywords

Digital magnetic recording; Digital magnetic recording; Equations; Magnetic heads; Magnetization; Shape; Signal processing; Space vector pulse width modulation; Surface treatment; Telegraphy; Telephony;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.1970.1066986

Filename

1066986