Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1986-07-31
1988-02-23
Swann, III, Glen R.
Communications: electrical
Condition responsive indicating system
Specific condition
3072191, 342 27, G08B 1324
Patent
active
047273607
ABSTRACT:
A batteryless, portable, transponder useful in a tag for a presence detection system. The transponder detects electromagnetic radiation at a first predetermined frequency and responds to said detection by transmitting electromagnetic radiation at a second frequency that is a subharmonic of the first frequency. The transponder includes an amorphous magnetic material component for storing energy from the electromagnetic radiation detected at the first frequency for transmission as the electromagnetic radiation transmitted at the second frequency. In one embodiment the transponder includes a thin, flat ribbon of low coercivity magnetostrictive amorphous magnetic material having a transverse uniaxial magnetic anisotropy defining a magnetomechanical resonant frequency "f" in accordance with the dimensions of the ribbon, when in the presence of a magnetic bias field of a predetermined intensity, wherein the ribbon responds to the detection of electromagnetic radiation having a frequency "2f" by transmitting electromagnetic radiation at a subharmonic of the frequency "2f"; and means for biasing the ribbon with the predetermined magnetic bias field. In another embodiment, the transponder consists of a single resonant circuit including a nonlinear inductor having a core made of amorphous magnetic material; and a capacitance connected in series with the inductor to define the resonant circuit. The core of the nonlinear inductor includes an elongated thin, flat ribbon of low coercivity amorphous mangetic material. It has been observed that this resonant circuit exhibits a bifurcated frequency-division characteristic in relation to the amplitude of the detected electromagnetic radiation at the first predetermined frequency, whereby additional frequency divisions occur as the amplitude is increased. A coded tag includes two amorphous magnetic material transponders that detect electromagnetic radiation at different frequencies.
REFERENCES:
patent: 4298862 (1981-11-01), Gregor et al.
patent: 4314373 (1982-02-01), Sellers
patent: 4481428 (1984-11-01), Charlot, Jr.
patent: 4484184 (1984-11-01), Gregor et al.
patent: 4495487 (1985-01-01), Kavesh et al.
patent: 4510489 (1985-04-01), Anderson, III et al.
patent: 4510490 (1985-04-01), Anderson, III et al.
patent: 4553136 (1985-11-01), Anderson, III et al.
Mitchell et al., "Magnetoelastic Effects in Fe.sub.71 Co.sub.9 B.sub.20 Glassy Ribbons", J. Appl. Phys. 50 (3), Mar. 1979, p. 1627.
Modzelewski et al., "Magnetomechanical Coupling and Permeability in Transversely Annealed Metglas 2605 Alloys", IEEE Transactions on Magnetics, vol. MAG-17, No. 6, Nov. 1981, p. 2837.
M. J. Feigenbaum, J. Stat. Phys., 19, p. 25, 1978.
P. S. Linsay, Physical Review Letters, vol. 47, No. 19, pp. 1349-1352, Nov. 1981.
Feigenbaum, J. Stat. Phys., 21, p. 669, 1979.
Charlot, Jr. Lincoln H.
Ferguson Lucian G.
Callan Edward W.
Security Tag Systems, Inc.
Swann III Glen R.
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