Tracking what’s happening with sensors today is an intimidating task. If you have US$2700 you can get a big report on Wireless Sensor Networks from Bharat Book Bureau, which appears to be based in India. If you don’t have this amount to spare, you can get a feel for what’s happening by just reading the long ad for the report, including the detailed table of contents. The summary has helpful orientation material:
Many now refer to traditional active RFID as First Generation. Examples of this include the device that opens your car from a distance and the device in your car windshield that uses a battery to incur and record non-stop tolling charges. Another example is the widespread tracking of military supplies and assets by electronically recording when they have been near an electronic device that reads the tag using radio waves. Real Time Location Systems RTLS, that continuously interrogate the tag from a distance, are called Second Generation active RFID and WSN is called Third Generation because it works in yet another completely different manner to provide its unique benefits…
Progress is now rapid and the much smaller size of the latest WSN tags is one indication of this. While the original concept was for billions or even trillions of tags the size of dust, the first ten years of development of USN has more often seen expensive tags, some the size of a videotape or, more recently, palm sized. However, further miniaturisation and cost reduction are now imminent.
The ToC lists many intriguing projects and companies worth a web search. There is a section on Impediments, which includes privacy concerns as the first listing. We can help with that! —Chris Peterson