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Multiplexing techniques; analog one explained

Short answer

The three main multiplexing techniques are Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), and Wavelength Division Multiplexing (WDM). FDM divides the link bandwidth into non-overlapping frequency bands; each signal modulates a different carrier and all are transmitted simultaneously with guard bands to prevent interference. At the receiver, band-pass filters and demodulators separate the signals.

List three main multiplexing techniques and briefly explain any one of the analog multiplexing technique.

Three main techniques

  1. Frequency division multiplexing (FDM): analog, each signal has its own frequency band.
  2. Time division multiplexing (TDM): digital, each signal has its own time slot.
  3. Wavelength division multiplexing (WDM): optical, each signal has its own light wavelength.

FDM (analog) explained

In FDM the link bandwidth is divided into non-overlapping bands. Each input signal modulates a different carrier (f1, f2, f3), moving it to its own band. The modulated signals are added and sent together at the same time. Guard bands prevent overlap. At the receiver, band-pass filters separate the bands and demodulators recover the signals.

 m1 -> [Mod f1] m2 -> [Mod f2]-> [ + ] === link === [BPFs + Demods] -> m1,m2,m3
 m3 -> [Mod f3]/

Example: radio and TV broadcast stations; telephone voice channels of 4 kHz each in a group of 12 (60–108 kHz).

✓ Answer checked by Claude Sonnet 5.5

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