Assertion: radio's channel | /r/ObjectUse | used for each aircraft
Facets:
value: except for 2.4 ghz band
type: OTHER
Source sentences:
text: Each aircraft needs a way to determine which transmitter to receive communications from, so a specific channel within the frequency band is used for each aircraft (except for 2.4 GHz band, and amateur radio-only 70 cm systems; which use spread spectrum modulation, described below).