To give you an idea of where I’m going to take this, let me ask a few simple questions. Would you buy a mattress without laying down on it to see if it’s comfortable? What about a motor cycle or car? Would you buy one without a test drive? In that same vain, would you want your company to invest in UHF (ultra-high frequency) RFID (radio frequency identification) equipment for a RFID project without anything more than specs if you didn’t have to? I would assume the answers are: “of course not”.
We always want assurances that the RFID technology we buy today will provide a solution that meets or exceeds our expectations, whether that be ROI, performance/through-put, efficiency or all of these. After all, failure is usually not an option, especially with our more costly investments. And when those technology investments can affect other parts of our organizations like IT, purchasing and logistics support like an RFID system can, we especially want to be sure they will work.
UHF based RFID in many cases can be used to provide automated part tracking in a logistics chain between plants, tracking parts moving around a warehouse and even providing tracking and traceability on a production line. In most or all of these cases, the UHF RFID data will need to be used by a MES, ERP or even a control system to provide the greatest use and visibility. When you look into using UHF based RFID, understanding how it works is a good start, but it’s usually not good enough to assure success for industrial applications. In comparison, usually knowing the specs with the more localized or “near field” technologies like HF (high frequency) or LF (low frequency) based RFID can provide most of the answers to succeed. (See Choosing RFID For Industrial Applications whitepaper for more technical information on these technologies.)
UHF’s technology is designed to work for longer distances, in some cases as much as 3 to 6 meters. This also means there can often be interference present of some sort or another. Because of this distance advantage, many times this same interference is transient. It can be people, vehicles, or mobile structures like skids or equipment. Knowing where this interference is or what can cause it can mean the difference between reliable detection or disappointing data “holes”. This is where a “site survey” can not only give you the confidence that your system design will work, but provide the technical recommendations and system design foundation to build your installation with far greater reliability.
A good site survey means bringing a UHF system out to your facility where the system will be used in creating the most realistic as possible simulation of your application in action. For example, let’s say you want to detect and read UHF RFID tags mounted on powertrains or their carriers as they arrive off the truck. For the survey, you might create a temporary gateway around the receiving door and run the parts or carriers through to determine the effectiveness of the positioning of the antennas and tags. This could also determine how many antennas you might need, the tag type needed and what might interfere or create inaccuracies like people walking through or other tagged parts left nearby. This is just an example of what a site survey can tell you. Many companies offer them, but be sure they actually include on-site testing with a documented report including results and recommendations for use. Many times on-site survey services are fee based, but in most cases this fee is a worthwhile investment to help guarantee success and assure higher reliability the first time.
Armed with this information, installing a UHF system is not just guessing what might work best, its knowing. Success and reliability always start with having the right information and a site survey before buying and installing a UHF based RFID system is the “best practices” approach towards a great investment that will meet your expectations.