Quasi Baseband Equalization and Detection
Original Publication Date: 1986-Jun-01
Included in the Prior Art Database: 2005-Mar-09
In magnetic recording channel equalization and detection, no equalizer is a perfect match for channel response. To increase recorded data density and to enhance signal-to-noise ratio in a magnetic readback system, quasi baseband equalization, also called quasi-PR1 (QPR1) equalization, is proposed as a better match for overall channel response because the passband of an ideal PR1 equalizer extends to DC. PR1 equalization introduces intersymbol interference (ISI) and bit coding redundancy because actual channel response does not extend to DC. However, such penalties can be overcome with prudent and coding of data and selection of low frequency alteration. In the present configuration, input data is encoded in 4/8 code at rate 3/4.