Block diagram of spread spectrum digital communication

The block diagram of spread spectrum digital communication is shown in above fig. the basic elements of a spread spectrum digital communication system with a binary information sequence at its input at the transmitting end and its output at the receiving end.

Functions of each block:

• Channel encoder : The channel encoder adds some redundant bits to the input bit sequence in properly defined format.
• Pseudorandom generator : It produced a pseudorandom or pseudonoise binary valued sequence.
• Modulator : Pseudonoise (PN) binary valued sequence is impressed on the transmitted signal at modulator.
• Channel : Medium through which signal travels towards receiver.
• Demodulator : The impressed PN sequence removed from the received signal at the demodulator.
• Channel decoder : The decoder at the receiver uses the coded bits to reconstruct error free accurate bit sequence and reduce the effects of channel noise and distortion.