The fast growing business of RFID smart shelves
Smart shelves and cabinets have long been considered one of the most promising opportunities for the RFID industry. Perpetual inventory and location of all products in a store, hospital, library or manufacturing plant opens up a host of business cases with demonstrable ROI's.
Preventing stock outs, identifying misplaced items, helping customers finding the products they want, controlling who checks out valuable items, or ensuring availability of critical parts are just a few examples.
However, deploying smart shelves and cabinets on a large scale is faced with several important challenges.
Many shelves and cabinets are made of metal, a material which reflects radio waves. In many cases, items are densely packed, and often include liquids or metallic parts, making it difficult to achieve high read rates. Different applications require different resolutions in time and space (e.g. inventory every 30 s, and 50 cm location precision). To top it off, smart shelves and cabinets are usually deployed in environments extremely sensitive to cost.
Despite all these challenges, smart shelves and cabinets with versatile, reliable and cost-effective architectures are a reality today. After 5 years of research and development and on-the-field experience, we have verified that the best approach for developing high performance shelves and cabinets is to use a fairly large number of low-cost RFID antennas interconnected by multiplexers. This architecture provides high reliability through redundancy, minimizing usual problems like multi-path. In addition, this approach allows locating the tagged items with high accuracy and resolution.
Different antennas need to be used for metallic and non-metallic furniture. In both cases, it is essential that the antennas have a very low profile in order to facilitate retrofitting and occupy as less space as possible. In a typical installation antennas will be placed 25 to 50 cm apart, so that a typical gondola 130 cm wide and 200 cm tall can be equipped with 16 to 32 antennas, depending on the number of shelves.
The rest of the installation consists on the connection of all the antennas to a reader or a set of readers. For this it is important to have a wide set of available multiplexers (4 ports, 8 ports, 12 ports, 16 ports) and power splitters (x2, x4, x8) that allow all the combinations needed to tailor each installation to its particular requirements of shelf material, product type and density, time, and location resolution, at a minimum cost.
The final component of this architecture are readers, which play a key role. It is important that the readers allow two levels of multiplexing in order to share the same reader between different gondolas. Typically, the two levels of multiplexing are used to decouple horizontal and vertical multiplexing, making the installation simpler, cleaner, easier and cheaper to install and maintain. Two-level multiplexing allows the connection of up to 1.024 antennas to a single reader, bringing down the cost per installed shelf meter.
In summary, smart shelves and cabinets have finally come of age, and are ready for large scale deployment in retail, healthcare, manufacturing and other environments in which precise control over the location and inventory of products, tools, supplies, manufacturing parts or any other items is needed.
if you want to know more about Keonn technology for smart shelves.