What did Sun learn along the way? The largest lessons were about how to successfully deploy RFID in a manufacturing production environment. Sun uses wireless routers and cell phones in its manufacturing facilities, for instance. But in the internal trial, Sun managed to prevent wireless interference by running RFID equipment at the 915 MHz frequency level. Metal proved more challenging, though. "We use lots of metal in our products and our [factory] carts. Theres metal in the parts. RFID tags are made of metal, too," according to Liu.Through trial and error, Sun discovered that linear RFID antennae worked better in the manufacturing setting than the radial variety, he said. Moreover, RFID tags used in the experiment needed to be carefully aligned, in "predictable locations" so that no tag blocked any of the others. "Each [inventory session] involved several tags, and the reads were happening simultaneously," Liu said. "You also had to leave enough air space, so that none of the tags were surrounded by metal." As another remedy, Sun engineers built their own RFID gateway for the initial pilot, using PVC plastic pipes rather than metal. Under these conditions, results showed a read accuracy of 99.5 percent, with just one missed read. Other hardware and software used in the first test included a single RFID reader with two antennae from Alien Technology; a Sun Enterprise 450 server; a Sun LX50 server; Suns EPC-compliant Java RFID System software; an Oracle relational database; a reporting module from Brio; and a GUI specifically created for production workers. Click here to read about EPCglobal standards for RFID. Now, before deciding whether to move ahead with a more extensive piloteither with or without a partnerSun needs to get a better idea of "exactly what we need to do to comply with the DODs RFID mandate," Liu said. The Defense Department supports both EPC and ISO specifications for RFID, he said. "But its our conception that these specs will converge in the next generation of the EPC standard." Check out eWEEK.coms Supply Chain Management & Logistics Center for the latest news and analysis of enterprise supply chains.
Essentially, the trouble with metal is that it blocks RF waves. "But we found that we could avoid these difficulties through proper selection and placement of the tags and antennae," he said.