PCM Receiver (Decoder) :

A PCM signal contaminated with noise is available at the receiver i/p

The regenerations circuit at the receiver will separate the PCM pulses from noise and will reconstruct the original PCM signal

The pulse generator has to operate in synchronization with that at the transmitter. Thus at the regeneration circuit o/p we get a “clean” PCM.

The reconstructions of PCM signal is possible due to digital nature of PCM sig. The reconstructed PCM sig is then passed through a serial to parallel converter.

o/p of this block is then applied to a decoder.

The decoder o/p is sequence of a quantized exactly the o./p operation of encoder is thus obtained as quantized PAM signal as quantized multi-level pulses.

This quantized PAM signal is passed through a low pass filter to recover the analog signal, x (t).The low pass filter is called as the reconstruction filter and its cut off frequency is equal to the message bandwidth W.