Describe why modulation is necessary for communication.
Antenna Size:
We know that
Multiplexing:
Multiplexing is the technique use for transmitting several information bearing signals over the same physical channel simultaneously. It is possible; if different type of base band signal is modulate by the different high ranges carrier frequency. So, for multiplexing modulation is required.
For long distance communication:
The message signal is contain very low frequency component. The low frequencies component cannot coverage long distance when they are transmitted from the source. The low frequency component can be easily attenuated compare to the high frequency component when it is transmitted over the communication channel. By modulation low frequency components of the signal is converted in to high frequency signal. So, this high frequency signal is covered a long distance communication.
Hardware problem:
The modulation process enables us to avoid many hardware problems which would be encountered if there were to be no modulation.