Research Of Hard Disk Drive Channel And Servo Coding Technology In Pattern Generator

People ask for even higher level of storage technology, with the rapid innovation of digital information industry. Hard disk drive is the major media form of current data storage equipment. A blueprint of servo pattern generator is introduced as servo pattern generator being critical during the whole hard disk drive manufacturing progress.Servo information needs encoding progress in servo pattern generator. So the structure of servo information is introduced. And at the meanwhile, a novel servo pattern called tribit encoding method is proposed. The simulation result of the comparison of tribit encoding and the traditional encoding method which called di-bit encoding demonstrates the advantage of the tribit encoding method.In hard disk channel technology, an alternative Viterbi algorithm is proposed here with the simulating comparison result. The result tells that the bit error rate gap between the two encoding pattern is 1-2 magnitude which verifies the possibility and the advantage of the alternative viterbi algorithm.In read channel, filters can lower the bit error rate. Traditional filters, which are based on least mean square algorithm, are used to equalize the wave form and lower the bit error rate. Here we suggest a new sel of filters used in read channel of hard disk drive equipped on vehicles. It eliminates the impulse noise by median filter and the periodic shock by linear prediction filter. Ultimately, the simulation result of the new filter can offer powerful evidence to the proposal.