Atmel has a 800/900MHz IEEE 802.15.4 RF transceiver for low power wireless applications such as ZigBee.

The AT86RF212 offers a link budget of up to120dB in the 800MHz and 900MHz ISM bands available in Europe and North America, respectively. The link budget is the result of the -110dBm sensitivity offered by the device and the maximum output power of +10dBm.

Designed for low current consumption in both active and in sleep mode, the device’s current consumption in receive mode is 9mA and the consumption in transmit is 17mA at a power output level of 5dBm. The sleep mode current consumption is down to 0.2µA.

The 20/40kbit/s and 100/250kbit/s data rates supported by the device are compliant to IEEE 802.15.4-2006. High speed data rates such as 200/400/1000kbit/s are also supported enabling wireless applications demanding more bandwidth.

Security is handled by an AES 128-bit onboard hardware engine.  

See http://www.atmel.com/avr