That’s a great question, and one a lot of people struggle with. Here are a few things to consider when selecting an RFID system:
1. Determine the potential applications and their business benefits. There are many things you can do with an RFID system, but not all will deliver a return on investment, and the ROI can differ dramatically for different applications. Let’s say you can track people, tools, assets, parts bins and paperwork with parts’ histories in a manufacturing facility. Tracking tools and assets might deliver the biggest ROI, so those applications are the ones that should determine your selection criteria. You can later determine whether you can track the other things with the same system.
2. Consider the read range required. Read range is a critical factor in choosing the right system, because it is one of the biggest factors differentiating low-frequency (LF), high-frequency (HF), ultrahigh-frequency (UHF) and active RFID systems. If you need to locate specific objects over long distances, you will almost certainly want to use an active RFID system (the lines are blurring a bit, however, with new phased-array antenna systems). If you want to identify vials of biological samples in a vial holder, for instance, you will want to use an LF or HF system that can read tags at close range.
3. Consider when and where you need to collect data regarding the movement of goods or assets. In some cases, you just want to know a container moved from one room to another. A passive system will be fine in such a scenario, because you can set up a portal and read the tags as each object moves through the portal to the other room. In other cases, you need to know the location of objects within a facility or yard at all times. If that’s the situation, you will want an active RFID real-time locating system.
4. Consider the environment. Are you reading tags indoors or outdoors. Are you trying to locate objects in open spaces, or are there a lot of aisles with metal shelving and or metal bins or products that can deflect reader signals and inhibit performance?
5. Consider the object’s size. This might or might not be a factor, but clearly it is hard to put an active tag on a wristwatch. Smaller, less expensive objects are usually tracked with passive systems.
These are some of the major factors to consider, but I would encourage anyone serious about deploying an RFID system to work with a skilled integrator who has experience deploying both active and passive systems. I’ve provided some general rules of thumb, but there are exceptions to all of these. A good systems integrator will be able to determine the proper technology that will enable you to achieve your business objectives most cost-effectively.
—Mark Roberti, Editor, RFID Journal
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