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Difference in between Time division multiplexing (TDM) and Frequency division multiplexing (FDM)

Difference in between TDM and FDM:

This page on FDM versus TDM describes difference between FDM and TDM multiplexing. FDM is the short form of frequency division multiplexing and TDM is the short form of time division multiplexing.
In FDM each signal is modulated onto different unique RF carrier frequency and all carrier frequencies are separated significantly so that bandwidth of the signals do not overlap in frequency domain.
Difference in between TDM and FDM
Figure: Difference in between TDM and FDM

   "Time-division multiplexinin telecommunications for telegraphy systems in the late 19th century, but found its most common application in digital telephony in the second half of the 20th century."

      In telecommunicationsfrequency-division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping (guard band provided) frequency sub-bands, each of which is used to carry a separate signal. These sub-bands can be used independently with completely different information streams, or used dependently in the case of information sent in a parallel stream. This allows a single transmission medium such as the radio spectrum, a cable or optical fiber to be shared by multiple separate signals.

Wavelength-division multiplexing (WDM) is a method of combining multiple signals on laser beams at various infared (IR) wavelengths for transmission along fiber optic media. Each laser is modulated by an independent set of signals.

Wavelength-division multiplexing (WDM) Video:

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