3.9 Time-Division Multiplexing At the receiver the decommutator has to be synchronized with the incoming waveform so that the PAM Samples corresponding to source l will appear on the channel l output. This is called frame synchronization, which is very important for TDM system Low-pass filters are used to reconstruct the analog signals from the Pam samples Because of isi resulting from poor channel filtering, PCM samples from one channel may appear on another channel. often called crosstalk, even though perfect bit and frame synchronization were maintained4 3.9 Time-Division Multiplexing • At the receiver the decommutator has to be synchronized with the incoming waveform so that the PAM samples corresponding to source 1 will appear on the channel 1 output. This is called frame synchronization, which is very important for TDM system. • Low-pass filters are used to reconstruct the analog signals from the PAM samples. • Because of ISI resulting from poor channel filtering, PCM samples from one channel may appear on another channel, often called crosstalk, even though perfect bit and frame synchronization were maintained