HUT Communications Lab. / Timo O. Korhonen
6
Short history of pulse coded modulation
nA problem of PSTN analog
techniques was that transmitting multiple channels was difficult due to
nonlinearities resulting channel cross-talkn1937 Reeves and
Delorane ITT labs. tested TDM-techniques by using electron-tubes
n1948
PCM was tested in Bell Labs
nTDM
was taken into use in 1962 with a 24 channel PCM link
nThe
first 30-channel PCM system installed in Finland 1969