Radio System

The Air-Frame range of products use Frequency Hopping Spread Spectrum (FHSS) radio technology.

Frequency Hopping Spread Spectrum technology is derived from military radio technology where it was designed to be inherently secure and reliable under adverse battle conditions. The alternate technology that is sometimes used in this band is Direct Sequence Spread Spectrum (DHSS) which we have chosen NOT to support. You can read our comparison of the two technologies here.

Spread Spectrum technology divides the available spectrum into a number of separate channels. In the case of the 2.4 GHz ISM (Industrial, Scientific and Medical) band the available spectrum is from 2.4 GHz to 2.4835 GHz in most countries (France, Spain and Japan use a slightly modified band).

In Frequency Hopping technology this band is divided into 79 separate 1 MHz channels (the remainder is unusable 'guard-bands'). The radio cycles through (or 'hops' onto) these channels using a pseudo random sequence such that all the channels are used every 30 seconds or less. Since there are many other users in this band (and many other forms of interference) a frequency hopping system may receive interference on any single channel (for a maximum of 400 ms) but then 'hops' onto another channel where it is unlikely to experience the same interference problems.

Frequency Hopping is a very robust and reliable Spread Spectrum technology and ideal for applications where data reliability is critical.