RFID? RTLS? Are they the same thing? Sure, each acronym has a distinct root meaning, but I still hear and read RFID and RTLS used interchangeably. So, which should we use when? Fortunately, Zebra Technologies has published a white paper, RTLS 101: What It Is and Why You Need It, that distinguishes RTLS from RFID as the terms are most often used in modern contexts.
The defining characteristic of RTLS, or Real Time Locating Systems, is that they deploy “active” tags, meaning that each tag transponder has its own power source, unlike those of “passive” RFID systems in which the transponder is powered remotely by the sensor that reads it. RTLS encompasses several technologies, including, in the strictest sense, active RFID systems. But because active systems increasingly rely on microwave rather than radio frequencies, the term RTLS has become the catchall for systems that use active transponders.
RFID, or Radio Frequency Identification, describes any locating system, either passive or active, that uses the radio-frequency range of electromagnetic signals (LF, HF and UHF) to transmit identification and location data. But, because its namesake radio frequencies are now used primarily for passive locating systems, the broader term, RFID, is increasingly used as shorthand for passive systems only, ceding labeling of active systems, with their increasing reliance on microwave frequencies, to RTLS.
Given the overlap of these terms, it’s little wonder that they’re often used interchangeably, but RTLS is now more likely to denote an active system and RFID a passive system.
The bands of radio and microwave frequencies most often deployed in RFID and RTLS systems are:
- 120-150 kHz: Unregulated low frequency (LF) radio. It has a range of about 4 inches in RFID systems.
- 13.56 MHz: A high-frequency (HF) radio spectrum dedicated worldwide to industrial, scientific and medical, or ISM, use. Its RFID range is from roughly 4 to 40 inches.
- 433 MHz: An ultra-high frequency (UHF) radio spectrum dedicated to short-range devices with a wide RFID operating range of from approximately 40 inches to 110 yards.
- 902-928 MHz (North America) and 865-868 MHz (Europe): A UHF radio spectrum (also designated ISM) that has a wide RFID operating range of about 40 inches to 40 feet. It is capable of moderate to high data speeds.
- 2450-5800 MHz: A bandwidth of the microwave spectrum that is also dedicated to ISM usage, including WLAN and Bluetooth. Zebra’s WhereNet RTLS technology utilizes the ISO/IEC 24730-2 standard of the 2.4 GHz frequency band to deliver read ranges of up to one mile with location accuracy of within 40 inches.
- 3.1-10 GHz: Bandwidth of the microwave spectrum that is defined as Ultra-wide band, or UWB. Its range extends up to approximately 220 yards, and it has a very fine location accuracy of within one foot. It is also capable of high data-transmission speeds. Zebra’s Dart ultra-wideband RTLS solutions utilize this frequency range.
Unlike GPS-based systems that rely solely on satellite signals that may be blocked by building structures and even dense trees, RTLS systems can be configured to accommodate any indoor or outdoor environment.
RTLS systems also require significantly less power resources than GPS – some can operate up to 7 years on a single battery charge. Better yet, RTLS systems cost considerably less to deploy.
For more information, please visit our website or call our toll free number 800-830-9523.