What Is an RFID Reader?
An RFID reader is a transmitter/receiver that scans RFID tags and interprets their data. Its range depends on the application; credit cards and ID badges must be held fairly close, while active tags have batteries that boost their signal for greater range.
To mitigate co-channel interference and fading, commodity readers employ channel frequency hopping. This creates a discontinuity in phase values every 0.2 seconds.
How RFID Readers Work
Like your own personal translator, RFID readers capture information from tags with radio waves. When an RFID tag is within range of a reader, the signal activates the chip and transmits a response, such as its EPC number or other data. The reader then uses the resulting information to understand the tag and communicate with it. The type of information a reader conveys depends on the type of RFID system being used.
RFID Readers can communicate with passive or active RFID tags. Passive RFID tags gather energy from incoming radio waves to operate, while active tags have their own internal power source for operation and sending the response to the reader. These two types of RFID tags use different communication methods and operate on a variety of frequencies based on the application they are being used for.
As a result, RFID tags are extremely flexible and can be integrated into almost any object or environment. This enables them to be scanned and tracked remotely, without the need for direct line of sight. Whether you’re tracking inventory at a warehouse, identifying items at a storefront or enabling customers to pay for your products using their prepaid toll account, RFID technology improves speed and accuracy of data collection. That translates into increased productivity and better service for your clients.
Handheld Readers
RFID readers also referred to as interrogators send radio frequencies to and from RFID tags. They can vary in functional frequency ranges, mobility characteristics, connectivity options and external device capabilities.
When a worker waves a handheld RFID reader within the range of multiple assets tagged with RFID, it will automatically detect and read each tag. The resulting data is uploaded to the system in real-time, eliminating manual entry errors and saving time.
A RFID reader can read RFID Reader an RFID tag even if it is not in direct line-of-sight (LOS). However, the reader must have enough power to activate the transponder and transmit a signal. Unlike barcode scanners, RFID tags can store more information and follow instructions/commands.
Advanced RFID systems can automatically track and relay items’ movements throughout the supply chain and into an ERP or financial management system. This helps reduce human error and eliminates the need to manually fill out forms or scan paper documents.
Another benefit of RFID is that it can speed up the in-store checkout process, enabling staff to focus on customer service. Using RFID can cut the amount of time customers spend at the register by up to 40%, giving them more time to browse the store and make additional purchases. It can also help prevent return fraud, which happens when a person returns stolen or worn merchandise for money.
Fixed Readers
As their name implies, fixed readers remain stationary while providing real-time monitoring of assets and inventory. Like handhelds, fixed readers communicate with tags via antennas but are designed to operate in a specific area without the need for line-of-sight.
These readers are typically used in environments that need to track high volumes of items, including manufacturing production lines and warehouses. As a result, they simplify high-volume inventory and material movement and provide visibility into your entire operations.
Unlike a traditional barcode scanner that requires line-of-sight, RFID readers and antennas transmit and receive data in the form of radio frequency signals. These signals activate the RFID tag to record and store information, which is then transmitted back to the reader via the antenna. The reader then processes the data for reporting and alerts, providing businesses with a centralized dashboard with visibility into their assets and inventory.
Fixed readers also have external antenna ports, allowing users to connect anywhere from one additional antenna to up to four different ones. This gives users flexibility on where they place the reader to best meet their needs. For example, if you’re tracking files in and out of a office, you may only need a small area of coverage, so one antenna will work well. Alternatively, for a check-in/check-out solution, you might need multiple antennas to cover a conveyor belt or finish line.
Vehicle-Mounted Readers
A vehicle-mounted reader mounts on the backrest of a forklift or other freight handling equipment to automatically log cargo locations as it moves around a warehouse or distribution center. For example, a fleet of mobile readers mounted on forklifts can “sweep” a laydown yard and provide location updates to thousands of RFID Reader materials all at once. This frees up project staff to work on other tasks and saves labor costs.
The vehicle-mounted readers need a direct line of sight with the RFID tags to read them. In addition to windshield or hang tag applications, these readers are used with license plate tags to monitor vehicle inventory, border crossing identification, and more. The read range depends on the type of RFID tag and the conditions under which it’s being used. A simple set-up with equipment overhead and several antennas angled toward the vehicle can usually net about 20 feet of range.
Choosing an RFID reader that can identify all types of RFID tags is key to getting the right data for your application. Some readers have a built-in software program that can interpret multiple frequency bands and identify all common types of RFID tags, while others use a method called deterministic detection to determine the signal of a particular tag bit by bit. This approach is faster than probabalistic detection but can be affected by environmental factors such as RF interference and the number of nearby tags.