The XBee 802.15.4 from Digi is a RF Module with Frequency 2.4 GHz (ISM), Supply Voltage 2.8 to 3.4 VDC, Output Power 1 mW (+0 dBm), Sensitivity -92 dBm, Data Rate 250 kbps. More details for XBee 802.15.4 can be seen below.
Compact and Powerful Bluetooth Smart SoC
2.4 GHz Random Phase Multiple Access (RPMA) Module
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