The effect of bandpass filters for thermal asperity suppression in perpendicular recording systems

Thermal asperity (TA) causes a crucial problem in magnetic recording systems because it can distort the readback signal to the extent of causing possible sector read failure. This problem becomes more severe in perpendicular recording channels because these channels contain a d.c. component. This paper presents a novel TA suppression method by use of a bandpass filter. We also investigate the effect of different bandpass filters for TA suppression. Results indicate that the proposed TA suppression method using a bandpass filter polynomial G(D) = (1+D)2(1-D) yields lower bit-error rate than the existing ones, and is robust to large peak TA amplitudes.