Software defined radio(SDR) has been with us for a while now with an increasing number of models on the market.
Taking away the hardware that usually decodes radio signals and doing the processing in a software based environment gives a flexibility that will grant any system a longer operational lifespan with today’s ever changing protocols.
For the hobbyist this is a wonderland, no more relying on the hardware limitations that are inherent with any radio that we buy, if we can program the SDR or run it through an already existing interface we have the access to a very powerful RF decoder.
Open Source software
Because any signal processing is done by software the ability to “tweak” or completely write new functions allows continued upgrading of your software radios functionality. As more and more of this software is available as open source there are always information resources to be found on the internet to make the job of altering the software easier.
By using SDR software on any home PC you open up recording facility’s that are only limited by the storage your computer has available along with the ability to monitor and decode signals across large chunks of the radio spectrum at the same time.
The Cost of SDR
The price of SDR technology varies widely at the moment and as with most radios is loosely based on frequency coverage and features. A high sampling rate will produce better results because it gives the decoding software more data to work with over a set time frame and this is also often reflected in the price.
A Cheap Way to Start with SDR
Looking to experiment with software defined radio but don’t want to spend a bundle of money to get started then there are some low cost ways to get going.
Dongle type receivers can be bought for under $20 and will work fine for general use like listening to most of the signals you would pick up on an basic FM VHF/UHF Scanner.
Once you have worked out the whole SDR process and you know its something that you want to invest more time in then maybe move onto more complicated systems. Starting in SDR this way keeps the initial learning curve small and you don’t end up with a expensive piece of kit that you will never use.
The Future of SDR
With this technology taking a firm hold across all sectors of commercial and private radio use and some recognized standards starting to emerge the option to obtain free software functions to run our SDR hardware is getting easier all the time.
Due to the very nature of SDR there will always be enough room for experimentation to keep anybody who likes to develop their own decoding software coming back time after time.
SDR radio photo courtesy Wikipedia