The block diagram of general transmitter architecture is shown in the Figure 1.
The data to be transmitted is analog or digital in nature
ADC : The real world data is analog in nature. ADC samples the analog signal and converts it to digital data.
Compression : To reduce the size of data to be transmitted, it is compressed.
Scrambler/Coding : provides a means to correct the data if any errors during transmission
Pulse shaping : reduce the signal bandwidth of data to be transmitted
Modulator : convert the bassband signal to RF for ease of tranmission
Power amplifier : Amplifies the power of the RF signal over long distances
Antenna : convert the voltage/current signal to electromagnetic radiation