Transmitter for electronic article surveillance system

摘要

An EAS transmitter for generating an EAS transmission with a preselected guardband, comprises an oscillator for generating a fundamental frequency pulsed waveform and circuitry for effecting spectral window shaping of the fundamental frequency waveform on a time basis corresponding with the guardband for reducing sidelobe energy in the guardband. The transmitter may further include circuitry operative on the spectral window-shaped fundamental frequency waveform for further reducing sidelobe energy of the spectral window-shaped fundamental frequency waveform in frequency correspondence with the guardband. Another EAS transmitter comprises a storage unit having stored therein the sidelobe energy-reduced spectral window-shaped fundamental frequency waveform and obtaining EAS transmissions by use of the stored contents of the storage unit.