Wireless Sensor Network

• Initial Requirement:

  Standalone data acquisition and control system reading physical parameters and transmitting the same through ISM band or GSM/GPRS services to a master control center and upload on internet using GPRS.

• Technology:

  Wireless sensor comprises of a group of sensor modules called Motes. These motes are slave devices which can be controlled, configured and programmed through a Master device placed at a short distance with in a local area. . The motes have capability to convert various physical quantities like temperature, pressure, humidity, light intensity, motion of object, etc. into electrical signals. These electrical signals are then processed by signal conditioner and converted to digital signals by ADC. This data is encrypted and relayed to Master device either through Zigbee, WiFi, ISM band or UWB short range communication. In this manner one master device communicates with several salves which are identified by their unique Id number in the network. Both mote and master device are battery operated. Intelligent power management within these devices makes them possible to work unattended for months.

  
  

  The master device possesses GSM-GPRS/ CDMA connectivity making it accessible from anywhere round the globe. The master device can upload data through GPRS to any internet website or can send SMS to any cellphone. Similarly, the master can be controlled and configured through a SMS send from authorized cellphone.

  
  

  Transducers for temperature, humidity, pressure, motion, proximity, acceleration, light, sound, pH, gas concentration, magnetic field, etc. have been integrated.

• Novel Features:

  • A wireless data acquisition system with long & short range capabilities
  • Round the globe connectivity
  • Fully automated, no manual intervention
  • Configuration and control of sensors through PC or cellphone
  • Zigbee, WiFi, ISM band for short range communication
  • GSM, GPRS and CDMA used for long range connectivity
  • Internet connectivity: Data acquired can be directly uploaded to website
  • Secure data transfer: Encryption algorithms used
  • Intelligent power management
  • Firmware upgrade can be performed through wireless
  • The various sensors that are integrated includes temperature, humidity, pressure, light, sound, motion, acceleration, magnetic field, pH, gas concentration (O2 , CO), proximity sensors, etc.
  • Can even be used to control any device through internet or cellphone

• Development Platforms & tools used:

  • Development Toolkit and Application environment (Proprietary of GSM chipset manufacturer).

• Specification:

  • GSM Quad Band 900/1800/850/1900 MHz and ISM band
  • ARM7 Core
  • Sensors include Temperature, Acceleration, Light, magnetism, pH, motion, sound, humidity, etc.
  • Improved RF performance
  • Reduced Power consumption
  • 3.6V Li-ion rechargeable battery
  • Longer battery life
  • Intelligent power management for better performance and battery energy conservation under weak GSM network regions.
  • User configurable for reporting time interval, Master number configuration, status reports, battery level monitor, power-down and sleep modes all through simple SMS commands

• Block Diagram of the System:

  

• Customizations possible:

  A further development includes development of Multi MACs for Zigbee, Wifi and Certified Wireless USB (CWUSB) into single chip called as Base Band processor.

• Areas of Application:

  Metrological calculations and forecast, remote monitoring of temperature, light, and other physical parameters, appliance control, etc.