Gaussian Frequency-Shift Keying (GFSK) is a type of Frequency Shift Keying modulation that uses a Gaussian filter to smooth positive/negative frequency deviations, which represent a binary 1 or 0. It is used by DECT, Bluetooth, Cypress WirelessUSB, Nordic Semiconductor, Texas Instruments LPRF, z-wave and Wavenis devices. For basic data rate Bluetooth the minimum deviation is 115 kHz.
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