Baseband modulation

1. What is baseband modulation?
2. What is baseband and passband modulation?
3. Does baseband use modulation?
4. Why are baseband signals modulated?

What is baseband modulation?

In baseband modulation the information is formated so that it is represented by digital symbols. Then pulse waveforms are assigned that represent these symbols. These waveform can then be transmitted over a cable. Baseband signals are not appropriate for propagation through many transmission media.

What is baseband and passband modulation?

Baseband transmission sends the information signal as it is without modulation (without frequency shifting) while passband transmission shifts the signal to be transmitted in frequency to a higher frequency and then transmits it, where at the receiver the signal is shifted back to its original frequency.

Does baseband use modulation?

Analog baseband FM modulates using frequency modulation. The output is a baseband representation of the modulated signal. The output signal's frequency varies with the input signal's amplitude.

Why are baseband signals modulated?

But a baseband signal cannot be transmitted over a radio link or a satellite because this would require a large antenna to radiate the low-frequency spectrum of the signal. Hence the baseband signal spectrum must be shifted to a higher frequency by modulating a carrier with the baseband signal.