HUT Communications Lab. / Timo O. Korhonen
41
Comparing TDM and FDM
nTDM and FDM (see the last
lecture) accomplish the same transfer efficiency (dual methods)nTDM:
simpler instrumentation; only commutator switches + LPF
(FDM: subcarrier modulator, bandpass filter and demodulator for every message channel)
(FDM: subcarrier modulator, bandpass filter and demodulator for every message channel)
nTDM
requires good synchronization
nTDM
can be accommodated to different signals and BWs by using different
modulation formatsnWith respect of fading wireless channel both methods
have advantages
and disadvantages
nTDM
is discussed more while discussing SDH later