MAGNETIC ARRAYS AND THEIR RESONANT FREQUENCIES FOR THE PRODUCTION OF BINARY-CODES

An array of cantilevers of varying lengths containing at least a layer of magnetic material has been fabricated to produce oscillations at t he resonant frequencies of the cantilevers,ia magneto-mechanical coupl ing. The acoustic or magnetic fields resulting from the oscillations w ere detected using microphones or detection coils. The presence or abs ence of an oscillation at a given frequency of a preselected set of fr equencies was used to represent a ''1'' or a ''0,'' respectively, to c reate a binary code. The array can be designed and assembled to serve as a multibit magnetic tag.