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Comment Re:Challenge Accepted (Score 3, Informative) 171

All recent RF chips for wireless are zero IF nowadays.

Not true, super heterodyne is still very popular.

A SDR approach will use a big DSP (vector DSP even) to do the processing in software.

Not really. Depending on your platform the industry trend is actually going away from DSPs. DSP operations are being implemented in FPGAs these days (since they're faster and the newer Virtex 6 or 7s (and whatever Stratix whatever) are really huge).

Comment Re:Challenge Accepted (Score 1) 171

You're just talking about different receiver structures (super heterodyne and direct conversion respectively). There's no receiver structure that's specific to SDR (in fact the USRP, which is an SDR, has a super heterodyne structure). IQ sampling doesn't have anything do with receiver structure either, super heterodyne receivers and direct conversion receivers can have IQ sampling (the USRP, a super heterodyne as I mentioned, implements IQ sampling). Also, implementing a filter with a sharp transition band is due to using a digital system, there's nothing special about SDR that let's you implement a 500 tap FIR filter, there *is* something special about digital system (FPGA, ASIC, DSP, GPP) that let's you implement a 500 tap FIR filter.

Comment Spectrum not overcrowded, mismanged (Score 4, Interesting) 147

I did my MS thesis on wideband spectrum sensing (just about everything under 2.2 GHz). Turns out the spectrum isn't actually overcrowded, it's underutilized, especially over 500 MHz. Look at some papers by the Shared Spectrum Company www.sharedspectrum.com/. This is common misperception and it's the result of FCC policies (that they're working on changing). The underlying problem is that institutions that have spectrum allocated for them now actually need it, just not most of time.

Comment Customize (Score 1) 253

You can write a script to SSH to each machine, copy whatever you need then wipe it. Wiping the machine remotely is the problem, there's a good article from Linux Journal by Kyle Rankin that describes a good way to do this. It's pretty recent (maybe two months ago), I haven't been able to find it on their website.

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