Digi's unique XII™ Interference Immunity technology is a proprietary hardware and software feature set that allows product designers using Digi products to create wireless systems that are immune to most RF interferers (cell phones, pagers, other wireless systems, etc.).
When operating within the 900 MHz and 2.4 GHz frequency bands, cell phones, pagers and other wireless systems can dramatically interfere with wireless links.
Digi's XII™ technology can block 60 dB of interference. Interference just 1 MHz away can be 1 million times stronger than the Digi signal and only degrade the receiver sensitivity by 3 dB. This interfering device would have to output more than 100,000 Watts to significantly affect the transmission of Digi products.
Digi products utilize frequency hopping spread spectrum communication that, by design, delivers additional protection against interference.
This article describes how Digi RF products are designed to have good out-of-band interference rejection from other sources of RF emissions 1MHz or more away from the frequency in which the Digi RF product is designed to operate. An out-of-band interfering radio is one that is intended to broadcast in one frequency but has RF energy that bleeds-over to affect a second radio operating on a different frequency. Final performance can still vary at any particular installation site dependent on both the physical environment in which the radio is installed and the amount of in-band and out-of-band interference sources broadcasting in that same localized area.