Do RFID Systems Read In Real Time?

April 8, 2021
What's the difference for RFID?

When considering an RFID system, one of the most attractive features is its ability to provide data in real-time. But what is real-time, since whenever we read RFID data - or any data for that matter - its immediacy is, by its very nature, past time. As good as antennas are, they cannot solve the time delay problem in a passive tag, active tag or BAP tag systems because a time delay always exists - albeit a very small time delay.

Real-Time Reads Vary For RFID Systems

Real-time should not be confused with continuous time. Active RFID systems give data continuously if they are programmed to do so. Passive RFID systems and BAP systems also can be configured to give continuous information, often more economically than active RFID systems deliver it.

More readers would be utilized in such a system. However, continuous reads on any of the platforms still have a "real time" time delay factor even at the point of direct data input in software and even more so when subjected to human reads and interpretation.

Because of this delay, it may be prudent when designing a system to eliminate the human component and build into the RFID system automatic responses triggered by software. Where high-speed manufacturing is taking place or in scientific experimentation, closer real-time reads may be necessary for accuracy.

Consider Frequency Of RFID System

The frequency of a radio wave affects how fast tags can be read (as well as how far they can be read from and the surroundings in which they can or cannot operate). When purchasers consider tag speed, frequencies are considered: a hertz being a unit of frequency of one radio wave cycle per second.

Low-frequency tags (LF) have a frequency of cycle measured in kilohertz (kHz), high-frequency tags (HF and UHF) have frequency measured in megahertz (MHz) and microwave tags are measured in thousands of megahertz to gigahertz (Hz) levels. These tag frequencies are provided in tag descriptions in the literature distributed by tag manufacturers.

request a quote

Manufacturing Decisions Affect Speed Of Read

Antennas catch and broadcast these frequencies sometimes efficiently and sometimes not. Inlay manufacturers must pair antenna design to chip type when creating inlays, converters must use appropriate encapsulation materials to facilitate wave penetration and RFID system installers must consider variables such as antenna positioning and polarity to guarantee fast, accurate reads.

Therefore, when data is transferred between tag and reader, RFID frequencies affect the speed of the transfer. Although modifications can be made, usually, the higher the frequency, the faster the read and the closer to true real-time the read will be.

Ask Questions When Choosing RFID System

Selecting RFID Tags requires you to ask questions.

Phrases like “faster than a speeding bullet” and “in the blink of an eye” are obsolete because, ironically, in some scenarios they are slow. Real-time readings of anything, including RFID readings, are impossible to achieve, but readings are close, very close to happenings especially with the use of technologies such as RFID, which reads in milliseconds.

The questions for you, the one implementing an RFID system, are

  • What is your definition of real-time?
  • What is your need for real-time?
  • Is real-time more important than other variables associated with frequency: read range, tag size, legal restrictions, cost

Upon answering these questions, you are closer to the design of your ideal RFID system. Experts in the field, including representatives from Metalcraft, will help guide you through all the peculiarities of RFID tagging. In real-time?  No, but promptly.

Colynn Black, Metalcraft's RFID Business Development Director spacer

About the Author: Colynn Black
Colynn is Metalcraft's RFID Business Development Director. He started his Metalcraft journey as an RFID Technician, moving onto being an RFID Lead/Technician, an RFID Engineer and then his current role. He enjoys being able to utilize his technical skills and experiences to aid Metalcraft in acquiring new partnerships and customers. He's married to his wife, Allie and he has two children named Cruze and Ella. He enjoys being outside, working with his hands to build things, working on his car/boat, golfing, ice fishing, reading and wrestling with his son. 



Innovation and insight delivered to your inbox

Subscribe to our Newsletter ►

Recent Posts

Posts By Topic

Recent Posts

  • May 10, 2023

    Asset Tracking for Restoration Companies

  • May 4, 2023

    Understanding 2D Barcodes

  • April 27, 2023

    What are the Components of an Asset Tracking System?