bbbking...
The following description from the 4P-Mobile Data Processing
site confirms that RFID can be used underwater:
"RFID enables contactless data communication between a tagged
object or a smart card/label and a host device. Data and
energy to power the tag are transferred through radio waves
at a specific frequency. No line of sight or orientation is
required between the tag/card and the reader. Cards and tags
can be read at high speed through walls and concrete,
underwater and at extreme temperatures. They are reusable
and rewritable also with highly secure encryption."
http://www.4p-mobile-dp.com/en/products/rfid/index_rfid.html
An article on the Modern Materials Handling website also
confirms this, but the full text is available only to
subscribers:
"RFID goes underwater for first time
By Staff
Modern Materials Handling
April 1, 1999
Abstract: To enhance process efficiencies and reduce
contamination concerns, Escort Memory Systems has
introduced the first submersible radio frequency
identification (RFID) passive reader/writer."
http://www.manufacturing.net/mmh/article/CA121388
Note that the article was written in 1999, so there
have no doubt been major developments in this area
since then.
The RFID Journal website offers a wealth of information
on its FAQs page, and says this about range:
"The read range of passive tags depends on many factors:
the frequency of operation, the power of the reader,
interference from metal objects or other RF devices.
In general, low-frequency tags are read from a foot
or less. High frequency tags are read from about three
feet and UHF tags are read from 10 to 20 feet. Where
longer ranges are needed, such as for tracking railway
cars, active tags use batteries to boost read ranges
to 300 feet or more."
http://www.rfidjournal.com/article/articleview/207#anchor#019
You will need to initiate contact with various vendors
in order to determine their ability to accommodate your
specific needs, but I have no doubt that a solution can
be found. The RFID Journal site notes this:
"There are many different RFID vendors with different
areas of expertise. We have compiled a director of
vendors around the world. Click on Find a Vendor in
the left-hand navigation bar to locate the type of
vendor you are looking for."
http://www.rfidjournal.com/article/articleview/207#anchor#021
"You can use our Vendor Search Engine to search by type
of company, technology, application, or product or service."
Their search options start on this page:
http://www.rfidjournal.com/article/findvendor
One of the vendors on their list seems to have the
technology you might require:
"Quelis ID Systems
This Quebec-based company offers RFID products for
harsh environments, such as the ocean floor, military
battlefields, construction sites and the open road.
Quelis? RFID transponders can be encapsulated in
epoxy, polycarbonate, clear PET or FDA-approved
rubber materials with diameters from 5/8 inch to
2 inches. The company?s tags are used on high-pressure
gas cylinders, military ordnance, heavy tools,
underwater marine equipment and other high-stress
applications."
http://www.rfidjournal.com/article/findvendor?region=United+States&function=RFID+transponder+(special+form+factors)
Another company that specializes in underwater technology:
"Sonardyne International is based in Yateley, England. The
company has offices in Aberdeen, Houston, Singapore, Brazil
and Norway. The company is recognised as a world leader in
the design and manufacture of advanced acoustic instruments
and systems for accurate survey, positioning and tracking
in shallow and full ocean depth operations within the
offshore oil and gas industries."
They have a page on their RFID system for cable tracking here:
http://www.sonardyne.co.uk/products/rfid.htm
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Additional information can be gleaned from further exploration
of the links provided above, as well as those resulting from the
Google search, outlined below.
Searches done, via Google:
RFID underwater
://www.google.com/search?q=RFID+underwater |
