Wsn basics
From emboxit
IEEE 802.15.4
- IEEE 802.15.4 at Wikipedia is the basis of many wsn protocols
- TI CC2520 2.4 GHZ IEEE 802.15.4/ZIGBEE® RF TRANSCEIVER DATASHEET
- Freescale MC13192: 2.4 GHz, Low Power Transceiver for 802.15.4 Ref Manual
6LoWPAN
- 6LoWPAN From Wikipedia
- The 6lowpan group has defined encapsulation and header compression mechanisms that allow (internet)IPv6 packets to be sent to and received from over IEEE 802.15.4 based networks
- TI CC1101 Low-Power Sub-1GHz RF Transceiver page
RF Networks
- Wireless ad hoc network at Wikipedia
- Ad hoc http://en.wikipedia.org/wiki/Ad_hoc
- CSMA Carrier Sense Multiple Access http://en.wikipedia.org/wiki/Carrier_Sense_Multiple_Access
- The first implementation of CSMA was Ethernet http://en.wikipedia.org/wiki/Ethernet
- CSMA/CA Carrier sense multiple access with collision avoidance at Wikipedia
- TDMA Time division multiple access http://en.wikipedia.org/wiki/Time_division_multiple_access
- Wireless mesh network at Wikipedia
- The earliest wireless ad hoc networks were the "packet radio" networks (PRNETs) from the 1970s, sponsored by DARPA after the ALOHAnet project.
- ISM bands http://en.wikipedia.org/wiki/ISM_band
Low power wsn
- Example of Total Low Power using low Duty-Cycle
- 0.5sec active time every 300sec(5min) is 1/600
- 30mA with duty-cycle 1/600 is 50uA
- 50 uA with battery 1.2Ah(Alkaline D-cell) is 24000hours = 1000days
- With better battery and more conservative power handling the battery life expectancy of 5 years is possible.
- Sub 1% Duty cycle of operation is considered necessary for Low Power Wireless Sensor Networks (WSN).