SDR stands for Software Defined Radio in which RF communication is done using software or firmware, in order to carry out signal processing tasks which are normally processed by hardware. This hardware includes mixers, filters, amplifiers, modulators, demodulators, etc. Therefore, SDR only uses an ADC and DAC to do Analog to Digital and Digital to Analog signal conversion along with antennas, without needing many hardware components. This, in turn, makes SDR much flexible and makes it easy to fix issues if a problem arises since most of the processing is done on the software rather than on the hardware. The software can be run either on a personal computer or an embedded system.
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