FS-FHSS
Frequency selection and frequency hopping communication technology is a unique spread spectrum communication technology.

FS-FHSS is developed to be applied in various wireless communication fields. It is innovated by GONSIN, a Chinese company. It has developed the unique FS-FHSS based on the spread spectrum communication technology. The new technology can monitor and select the undisturbed frequency band. FS-FHSS makes sure the stability of the communication. It is applied to GONSIN wireless conference system, which implements the discussion、simultaneous interpretation、voting and others comprehensive conference application functions. 

The feature of FS-FHSS: it uses the 2.4 GHz global frequency band, it does not require certificate. The wireless frequency points are abundant, 80 frequency points could be used; 2.4 GHz has high frequency carrier, the signal diffractivity is relatively weak so that other 2.4 GHz signal could not interfere the conference signal. Adopt FS-FHSS technology, it detect the wireless environment and select the usable frequency point before the conference, during the conference, it hops between the backup frequency points, which can avoid the interference source. It utilizes the efficient digital audio encode and decode technology, one frequency point can transmit 4 channels, it just need two frequency points to transmit 8 channels simultaneous interpretation signals. Because the system occupies relatively less frequency points resource and utilizes the FS-FHSS technology to operate, it can co-work with WIFI and other 2.4 GHz system. It applies the digital audio encryption and digital modulation to avoid any interception and malicious interference; the signal transmitting power could be modified in according with the application occasion, the adjusting range is from 50 meters to 500 meters( the customized system can cover 2,000 meters).

SPREAD SPECTRUM The idea of spread-spectrum radio transmission was proposed by the military who was seeking ways to prevent radio signals from being monitored or blocked by hostile parties. The two inventors came up with the notion of changing the frequency of a transmission at regular intervals faster than the enemy could retune.  A special receiver that knew the frequency-hopping pattern could follow it and pick up the entire transmission. The hopping patterns were controlled by the
punched holes in piano rolls became known as frequency-hopping spread spectrum(FHSS).

References

Telecommunications
Wireless