The word “Base” means root, origin and “Band ” means a specific frequency range in term of signal processing. So we can see the BASEBAND signal means original signal or we can say that the signal which carries actual information and has the original frequency range without any change in amplitude ,frequency and phase. That means baseband signal is the signal before any modulation process is started. Baseband signals usually have low frequency. Another name of baseband signal is narrow band signal.
So, from the discussion above we got some characteristics of baseband signal:
1. Original signal
2. Low frequency
3. Narrow band signals
4. Low power
5. Short distance communication
Example of analog baseband signal is an audio signal may have a baseband range from 20 to 20,000 Hertz.
Examples of a digital baseband signal may be Ethernet signals operating over a Local Area Network (LAN).
Now the question is that can we still transmit baseband signal with its default low frequency and low power? the answer is NO !!
Because of having low frequencies, baseband signals don’t have enough power to travel long distance over either in wired or wireless medium.
Due to successful transmission of a baseband signal in a long distance, we have to provide it enough power so that it can travels long distance without being distorted by noise in the electromagnetic or wired medium.
Therefore ,we have to convert the baseband signal to PASSBAND signal.
What is Passband signal?
Passband signal is signal which has a specific range of frequency typically high frequency. Passband signal is the converted or modulated version of baseband signal. Passband signal is the combination of carrier signal and original message signal or baseband signal.
1. Modified signal
2. High frequency
3. Wide band signals
4. High power
5. Long distance communication