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Software-Defined Radio Could Unify Wireless World
mjdroner writes "Technicians in Ireland are testing a device capable of skipping between incompatible wireless standards by tweaking its underlying code. The article states: 'The device can impersonate a multitude of different wireless devices since it uses reconfigurable software to carry out the tasks normally performed by static hardware. The technology promises to let future gadgets jump between frequencies and standards that currently conflict. A cellphone could, for example, automatically detect and jump to a much faster Wi-Fi network when in a local hotspot.'"
I've been researching similar technologies over the past few years because I believe we can see an amazing communications "utopia" by deregulating (or at least minimizing regulations) all the frequencies we're blocking for specific uses.
Software radios are not new technology, but the implementation has been fairly worthless as frequencies are set up for specific purposes. At any given moment in any given area, there is a ton of bandwidth going unused. Frequency hopping is already pretty well documented in how to maximize its use, and power allocation specifications have been out since pre-cell phone days. Combine that with a much wider bandwidth and we can see higher data rates, lower battery usage and maximum bandwidth allocation everywhere you go.
I know the FCC will never give up the bandwidth to the open market -- it is too lucrative for the few who are in cahoots with the licensing body. But I see so much happening just in the WiFi "unreglated" spectrum that I would really love to live in a world where all that analog TV, digital TV, analog radio, digital radio, CB, HAM and every other heavily regulated piece of spectrum could be allocated to being used for just information transmission. Software radios would set themselves to the best frequency possible to maximize transmission distance (as needed) and minimize power consumption (as needed).
What we have now is more kludge than efficiency. Can you imagine how incredible the Internet would be if we had nearly infinite spectrum to use (compared to the limited spectrum we have now)?
Sure, some people will say "What prevents Megacorp YYY from blasting 100,000 watts over every frequency?" That's pretty simple -- energy costs make it prohibitive to transmit anything but profitable data. The FCC has existed long past its useful life, maybe it is time to open up little bits of unregulated spectrum piece-by-piece and let's see what happens. These software radios are a huge step in the right direction.
Since we're talking about Software Defined Radio, I urge everyone with an interest in the subject to look at the GNU Radio project. They have designed a front end board using generic cable TV tuners feeding an FPGA to perform some initial processing, such as decimation and filtering. The data is then transferred over USB to the host, whose software performs the demodulation and decoding. It's a fascinating project and a great stepping stone into the field.
To really get started on SDR, check out the Ten-Tec RX320D shortwave receiver. It outputs a 12 kHz-wide IF signal from the front end to an audio jack, which can then be fed to a PC soundcard. There are a number of packages that can take this data and demodulate it, including DREAM, an open source DRM (Digital Radio Mondiale) decoder which allows you to listen to the new digital shortwave transmission standard that many of the world's broadcasters are beginning to experiment with.
Karma: Excellent Birds (mostly as a result of listening to Laurie Anderson)