RTLS Series - All RTLS systems are not created equal. (Part 1)
Real-time Locating Systems (RTLS) have been on the market for over a decade. Although they have many similar components due to utilization of active RFID technology, and a common goal to provide asset location identification (whether it is a pallet, vehicle or a person) in a real-time; the way the systems actually achieve this is often fundamentally different. While many RTLS systems use active RFID, others may utilize WiFi or Ultra Wide Band (UWB) technology, and can be found operating on various frequencies, from 128 kHz all the way to 5.8 GHz. There are basically three main types of RTLS positioning techniques: 1. Time of Arrival (TOA) 2. Received Signal Strength Indicator (RSSI) 3. Angle of Arrival (AOA)
The Time of Arrival technique includes; Time of Flight, Time of Arrival or One Way Ranging, Time Difference of Arrival (TDOA) and Symmetrical Double Sided-Two Way Ranging (SDS-TWR). The Time of Arrival RTLS systems measure the amount of time required for a signal to travel from the transmitter (tag) to the receiver (reader). A main advantage of the TOA system over RSSI system is that it achieves a higher accuracy of location identification and better performance in non-line of sight environments.
IDENTEC SOLUTIONS recently introduced a new product to their portfolio - an RTLS system, which uses one of the most sophisticated methods based on time of arrival, called double sided two way ranging. The system utilizes components such as i-Q350 RTLS tags, i-SATs (ranging nodes) and RTLS readers i-Port M350 RTLS. So, how does this system work? When the tag enters into the i-SAT and reader field, it initiates ranging with all the available i-SATs and broadcasts consolidating ranging information to the reader. The reader is connected to the position engine which further processes the collected data and produces the tag location.
The advantages of this system far exceed beyond the 1 meter accuracy location identification. Because only the readers require a host connection, the system is exceptionally easy to deploy and requires very minimal infrastructure support. In fact, the system can stand totally independent of main electric lines, as the i-SATs and readers can be also powered by a solar installation kit. And, the system does not require synchronization which is common with other positioning techniques which also reduce the complexity of installations. IDENTEC SOLUTIONS‘ RTLS system demonstrates an ideal combination of high accuracy, high speed and low cost infrastructure, which is of considerable value in today’s market.
By Eva Zeisel