0

I've read that ADSL uses frequency-divided multiplexing and only analog signals use FDM. Then why there's the term 'digital' in ADSL(Asymmetric digital subscriber line) if it uses analog signals?

KavG
  • 169
  • 1
  • 12

2 Answers2

2

A simple way to imagine it, digital signal is broken into different frequencies like a piano keys.

Then each tone is sent down the copper wire like a sound, this is then picked up at the far end and then Demodulated back into a digital string of 1s a nd 0s.

A modems name is created from the job it does as a Modulator / Demodulator.

Jay Best
  • 21
  • 3
1

The signal is digital, the line encoding that implements this signal is described in the real macro world with analog.

Andrew
  • 1
  • 4
  • 19
  • Does signal travel through transmission media as an analog signal? – KavG Sep 10 '21 at 16:02
  • Yes, in layman's terms. it's a combo of phase, frequency, and amplitude modulation/"shift-keying", aka "QAM". – Andrew Sep 10 '21 at 23:50