Wireless Sensor Network is one of the interesting wireless communication technologies. It is considered to be used both in research and in many applications. This kind of network consists of many wireless transmission nodes. Each node has their own small embedded computer which allows them to automatically build the communication network. This high flexible network capability is supported by lower level mechanism, the IEEE 802.15.4 Standard MAC+PHY layers. The MAC+PHY stacks is a primary mechanism that support the amendments of many higher level protocols such as ZigBee, WirelessHART, or 6LoWPAN etc.