Tracking with GPS, GPRS and RFID
To compare GPS vs. RFID for asset location purposes, you first need to understand the following technology:
- GPS (which stands for Global Positioning System) uses a signal processor to receive low-power satellite signals and calculate positioning. It can then transmits that information either through a cellular network or a long-range system like Symphony Link.
- Passive RFID (radio frequency identification) uses a reader that transmits a very powerful low-frequency RF signal to an RFID sticker. This sticker is made only of metal and silicone (think of the stickers you’ve seen in library books) and has no battery. The electrons in the RFID sticker become excited and begin to flow from the signal, causing the chip to wake up and transmit back to the reader at a much higher frequency.
- Active RFID doesn’t get the power it needs to transmit from an exciter but rather from a battery. (Hence, “active.”) The tag typically contains a Bluetooth chip and a single antenna. Every couple milliseconds, the tag transmits its identity to a reader.