Creating a Close Proximity Read Zone with a Near Field Antenna

By Times 7, Jul 26, 2023

Creating a close proximity read zone in RFID applications can bring numerous benefits, including improved accuracy, reduced interference, and enhanced data capture. RAIN RFID Near-field (NF) antennas can create well-defined read zones, minimizing stray reads. This blog will explain the significance of a close proximity read zone and guide you through creating one.

Why Create a Close Proximity Read Zone?

A close proximity read zone focuses the read field and limits the range at which tags can be read. This allows for more precise and targeted data capture. By confining the read zone to a specific area, the system can avoid interference from nearby tags or objects, improving accuracy and efficiency.

• Enhanced Accuracy: Precise and targeted reads, minimizing the chances of misreads.
• Reduced Interference: Mitigate interference by limiting the read range to the desired area, improving overall system performance and data reliability.
• Improved Efficiency: Unwanted reads outside the intended area can cause unnecessary processing and consume system resources. A close proximity read zone allows for more efficient data collection.

How to Create a Close Proximity Read Zone using a Near-Field antenna:

1. Turn down the reader power.
2. Use a RAIN RFID NF-only tag, such as the Smartrac NF Trap
3. Lower the RSSI threshold setting in the RFID reader.

For those who want a more technical read…

When to use a Near-Field antenna?

RAIN near-field antennas are recommended for tracking metals or liquids (which are usually very tricky to track). Far-field electromagnetic fields get absorbed by liquid assets such as pharmaceutical drugs, shampoos, or soaps, while the near-field’s magnetic field is not subject to RF absorption.

Near-field antennas are also preferred as they create defined read zones to limit stray reads. However, unlike other NF technologies, such as NFC, the RAIN Near-Field zone is not limited to the antenna’s surface and can read at a greater distance.

What is the difference between Near-Field vs. Far-Field antennas?

Near-field and far-field concepts play a significant role in RAIN RFID applications. When an RFID reader energizes a reader antenna, the antenna transmits electromagnetic waves (fields) into the free space. Depending on where the waves move and the distance they travel from the transmitting antenna, they will be classified as near-field or far-field. Far or near-field electromagnetic fields can power RAIN tags.

Electromagnetic waves combine electric (E) and magnetic (H) fields that are orthogonal and in phase with each other. The electromagnetic fields vary as a function of distance from the transmitting antenna. This is broadly classified as the near-field region and the far-field region.

The reach of RAIN near-field zones is relative to the antenna’s gain and will increase or decrease with the reader’s power output. Our True NearField antenna series have a very low gain with only a few far-field components. Thus, a controlled magnetic field provides reliable reads over the antenna’s surface, showing minimal dead zones.

Optimize settings, NF antennas, and tags for a close proximity read zone!

Combining near-field antennas, optimized settings, and suitable tags can ensure reliable data when achieving a close proximity read zone. If you need help creating a close proximity read zone, contact us at sales@times-7.com.