We have a lot of RFID based customers on the go at the moment and the new website is soon going to be a lot clearer with what’s available in terms of Rugged PDA’s with RFID features.
The most common questions we’ve been asked the past couple of weeks has been about the types of RFID, the distances they read at and why they should use a certain type of RFID at all, so I’m going to cover this off right here in a few blogs.
Today we’ll overview RFID and answer a few of these questions.
Low Frequency (LF) is older technology but has by no means been replaced by other standards. It’s not well supported by Rugged PDA readers but the technology is still current and sound and has its place. You tend to get higher read ranges than HF and the tag prices are typically a little bit more expensive.
High Frequency (HF) is newer technology and is really the cheaper RFID you tend to see on Ebay. For this reason it has been the driving force behind RFID uptake, but comes with its own set of issues. Rugged PDA RFID Readers will always have an HF option, the tags are the cheapest you will find but the read ranges and general accuracy are low, depending on what you’re using.
Ultra High frequency (UHF) These are the bad boy Readers that have large antenna and large batteries and UHF is your best chance of reading at over a metre distances. The tags are very robust, you can even get active powered tags but UHF solutions are the most empirical and costly to implement and use the larger tags and readers so they’re not for everyone.
Why do we have different RFID versions
Partly due to new standards being driven by different industries. For instance there are ISO standards driven by the cattle industry (ISO11784), partly driven by new requirements and partly driven by new technology. Each type has its place and range, security, cost, equipment availability and what kind of data you need to store all play a part in helping you decide the ideal type of RFID you need.
What about standards within each version
Well LF has the least standards and you find that an LF reader/writer will read and write to most non-specialist LF tags, UHF is a little bit different and due to the cost and complexity of UHF kit there are typically different standards as innovative new ways of increasing performance come out. HF is the most complex and where we see the most issues because people see HF as the cheap, easy and quick way to implement an RFID solution. By-an-large this is true for most projects that aren’t too fussed about refining ranges etc but you do have to be very careful of all the different standards in HF as they aren’t all compatible. Most readers will read the common ones, Mifare for instance is one such std within the ISO14443B created by Phillips but not all readers read all tags!
But LF tags are old and ae out performed by HF ones?
This is a myth, and is certainly not our experience here. In fact if anything LF out performs HF in most areas we have worked in. It also doesn’t get affected by “Crosstalk” due to the way it works so if you have many tags in range of a reader LF can often be more robust. Ranges if anything are greater too, now the reader plays a large part in this too but generally where we need 4-5cm or where we’re through a substrate like rubber or wood etc, LF will be the best choice.
Next we’ll go deeper and look at each where you would typically use each technology.
The Rugged and Mobile blog.