Z-Wave적용 무선 센서 네트워크 노드 구현에 관한 연구

Abstract

WSN(Wireless Sensor Network) is an essential technology for USN(Ubiquitous Sensor Network) and it consists of process treating collected information, transmitting and receiving devices and sink nodes. The Sink node roles sending the collected data by sensors. WSN is not designed for communication means, but for automated remote data collecting. And it can be utilized at scientific, military and commercial application.

There are many technologies such as Z-Wave, Zigbee, Bluetooth, UWB(Ultra-Wideband), NFC(Near Field Communication) for USN. Recently, Zigbee has been in the spotlight among low-power and low-rate technologies. Z-wave technology is similar to Zigbee technology. Z-Wave, a proprietary technology developed by Zensys of Denmark, is competing with Zigbee to become the standard for automated home controls. About 50 companies in USA or Europe adopt Z-wave technology and they are making several products. Comparing with other technologies, Z-Wave has an advantage of low power consumption, two-way RF communication and mesh network. Its merits are available to control a sensor and device. Z-wave is possible to make it lighter, more energy efficient. With this special features, Z-Wave is expected to be a available solution in USN area.

In this thesis, the platform of automated home sensor network with Z-Wave is studied and implemented. The Z-Wave chipset, the ZW0201, is used at each sensor board. The 8-bit microcontroller interrelated 8051 is adopted to synchronize and control a sensor node. The 8051 functions at 16MHz includes 2kbyte RAM memory and 32kbyte flash ROM memory.

Using the microprocessor, it receives or transmits digital data. Master sensor board is connected with a computer and RS-232c through UGI(User Graphic Interface).

SHT11 developed by SENSIRION is used for humidity and temperature sensor. The Z-Wave chipset, the ZW0201, and GUI is controled by C language. The compiler offered by developers kit of Zensys is used for implementing this system.

Realized sensor nodes are activated for the line of sight range 13m at hight 0m, 35m at hight 0.75m and 65m at hight 2m.

Output power is -3.619dBm at center frequency 868.42MHz. The system is stably operated over input power 3.3V and its current consumption is 6.8mA at standby mode, 30.3mA at active mode.