Adrian,

An SDR is a software defined radio.  In this configuration the radio 
consists of digital to analog converters with appropriate software that 
implements the radio's functions through the software rather than doing 
it in hardware.

This makes modifications and future improvements easy.  All you have to 
do is change the code in the program rather than do a hardware 
redesign.  This approach will in addition give the designers a minimal 
parts count.

Most of the heavy lifting is done with the software rather than the 
hardware.

I hope this helped.




Dave Marthouse N2AAM
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