eingereicht von KrystleLuk 23 days alt (via Www.Econom.Uu.ru)
Frequency modulation is used by radio. To understand frequency modulation, look at a signal with a frequency that is continuous and amplitude.
The frequency of this sign in unchanged or un-modulated, so there is no advice included. But once information has been introduced to this sign, the combination leads to a change to the frequency, which is directly proportional to this info.