How different audio frequency at the same time modulate single carrier frequency?

[Code Warrior]

One thing still confuse me. How different audio frequency at a same time modulate single carrier frequency. I mean a 100MHz FM transmitter is broadcasting Music, music contains audio frequency from 1KHz to 18KHz, so my question is how a multiple audio frequency modulate single RF carrier at a same time.

 

[vfone]

Re: RF & Modulation

https://cnyack.homestead.com/files/modulation/modfm.htm

 

[Bhanumurthy]

Re: RF & Modulation

Hi,
Itz possible for no.of modulating frequencies to modulate a single carrier.However, the time domain and freq.domain descriptions would be a bit complex.
The modulation index is defined separately for this case and also the power and current requirements.Lotz of books in literature explain these concepts.
Regards
Bhanumurthy.

 

[mwmmboy]

Re: RF & Modulation

In my opinion the better way to "see" the modulation process is in the time domain: so a signal (audio) modulates FM the carrier i.e.. instat for instant the phase of the carrier is changed from the modulating signal.

I hope this can help.

Bye

 

[mbyoussef]

Re: RF & Modulation

What's wrong with having a composite signal modulating an RF carrier. An FM modulator can work quite well with a composite signal as with a single tone signal.

 

[Code Warrior]

RF & Modulation

I given FM for example. It may be any type of modulation FM, AM, SSB, PM or any other. How a different audio frequency modulates a single carrier frequency at a same time. Suppose when a carrier frequency is busy with 1KHz audio how it also dance with other audio frequency on the same time.

 

[madengr]

Re: RF & Modulation

One thing still confuse me. How different audio frequency at a same time modulate single carrier frequency. I mean a 100MHz FM transmitter is broadcasting Music, music contains audio frequency from 1KHz to 18KHz, so my question is how a multiple audio frequency modulate single RF carrier at a same time.

The same way your ears hear all the frequencies at the same time. Look at 1 kHz, 3 kHz, and 5 kHz on a oscilloscope. It will look like a square wave (assuming you have the proper phasing). That waveform is simply as summation of the tones. The waveform is modulating the carrier. The modulation with subsequent demodulation is a linear process so you get the same shaped waveform out.

 

[Code Warrior]

RF & Modulation

Yes, speaker, mic, our ears response to different audio frequency at a same time thats what I want to know how it is possible.