Patents Represented by Attorney The Small Patent Law Firm
  • Patent number: 7495565
    Abstract: A method for controlling electronic article surveillance (EAS) transmissions is described. The method includes calculating system parameters associated with one or more of a desired frequency, a desired duty cycle, and a desired phase difference between antennas for a transmitter, and initializing a counter with a value based on the system parameters. The method also includes comparing a count from the counter to the system parameters, and modulating EAS transmission signals based on the comparison between the count and the system parameters. An EAS transmitter and an EAS system are also described.
    Type: Grant
    Filed: May 4, 2005
    Date of Patent: February 24, 2009
    Assignee: Sensomatic Electronics Corporation
    Inventors: Jeffrey T. Oakes, Thomas J. Frederick, Richard L. Herring
  • Patent number: 7444120
    Abstract: A method for controlling signal decay of a transmitted signal within a transmitter is described. The method includes measuring an amount of current induced back into the transmitter by the decaying signal, and using the current measurement to control the decay of the signal after the signal is transmitted from the load. A transmitter for an electronic article surveillance (EAS) system is also described which includes a current sensing circuit configured to at least sense an amount of current induced back into the transmitter by the load after transmission of the signal, and a transmitter control circuit configured to utilize the sensed current to determine an amount and a polarity of current to be applied to the load to reduce the induced current to a desired value.
    Type: Grant
    Filed: May 4, 2005
    Date of Patent: October 28, 2008
    Assignee: Sensormatic Electronics Corporation
    Inventors: Richard L. Herring, Jeffrey T. Oakes, Thomas J. Frederick