A basic communication system consists of three fundamental blocks:

1. Transmitter: Processes the incoming message signal (baseband signal) to make it suitable for transmission through a channel.
2. Communication Channel: The physical medium (like wire, optical fiber, or free space) that carries the signal from the transmitter to the receiver.
3. Receiver: Receives the signal from the channel and processes it to reconstruct the original message signal. Without a receiver, the transmission would serve no purpose.