A reconfigurable FPGA-based readback signal generator for hard-drive read channel simulator

A hard disk readback signal generator designed to provide noise-corrupted signals to a channel simulator has been implemented on a Xilinx Virtex™E FPGA device. The generator simulates pulses sensed by read heads in hard drives. All major distortion and noise processes, such as intersymbol interference, transition noise, electronics noise, head and media nonlinearity, intertrack interference, and write timing error, can be generated according to the statistics and parameters defined by the user. Reconfigurable implementation enables an update of the signal characteristics in runtime. The user also has the flexibility to choose from a set of bitstreams to simulate particular combinations of noise and distortion. Such customized restructuring helps reduce the area consumption and hence virtually increase the capacity of the FPGA device. The time to generate the readback signals has been reduced by four orders compared to its software counterpart.