초록 ▼

A method and system for decoding time-varying, two-frequency, coherent-phase data, such as data from the stripe on a magnetic stripe-bearing medium, includes detecting flux intervals at the beginning of a bit cell of such data; timing with a clock or counter the length of such a bit cell; digitally

A method and system for decoding time-varying, two-frequency, coherent-phase data, such as data from the stripe on a magnetic stripe-bearing medium, includes detecting flux intervals at the beginning of a bit cell of such data; timing with a clock or counter the length of such a bit cell; digitally determining the average length of at least the two bit cells immediately preceding the cell being measured; and digitally determining whether or not another flux reversal lies at or near the midpoint of the bit cell being decoded.

대표청구항 ▼

A system for decoding two-frequency, coherent-phase data encoded as a plurality of bit cells with each bit cell comprising the time between two consecutive clocking transitions and one or no datum transition between said two clocking transitions, said system comprising: means for detecting transitio

A system for decoding two-frequency, coherent-phase data encoded as a plurality of bit cells with each bit cell comprising the time between two consecutive clocking transitions and one or no datum transition between said two clocking transitions, said system comprising: means for detecting transitions; means for measuring the time periods corresponding to the lengths of said bit cells; means for determining the optimum time to test whether a datum transition, if any exists, has occurred within the currently-measured bit cell; and means for determining the probable time length of said currently-measured bit cell and means for determining the optimum testing time for the prior occurence of a datum transition in said currently-measured bit cell from the average time length of at least the next two preceding bit cells; means for detecting the occurrence of a datum transition, if any exists, within said currently-measured bit cell.