1. 3GPP. Presence Service: architecture and functional description—TS 23.141 v9.0.0. 3rd Generation Partnership Project, 2009.
2. ABI Research. Short range wireless ICs: bluetooth, NFC, UWB, 802.15.4, and Wi-Fi Market Forecasts, 2010.
3. Wireless sensor networks: a survey;Akyildiz;Computer Networks.,2002
4. The 3G IP multimedia subsystem (IMS);Camarillo,2006
5. CC2420 Datasheet. 〈http://www.ti.com/lit/gpn/cc2420〉.