Hello Georg, On Mon, 27 Sep 2010 18:40:08 +0200, "Georg Hofstetter" <[email protected]> wrote: > > The USRP provides 16MHz max. RF bandwidth IIRC.
The default maximum bandwidth is 8MHz (16-Bit I/Q samples, only 12-bit are used), it might be possible to switch to 8-bit, but I have not tried it yet. If you use the full USB bandwidth for one channel, you need two units for downlink and uplink. > Thought that would be enough for most (900MHz-)BTSs. > Maybe that was too optimistic, right. >From my understanding of the allocated GSM900 ARFCNs here in Germany it would be enough for E-Plus and O2 but not for Vodafone and T-Mobile. > But one USRP2 just for channel hopping should be enough? The USRP2 has 25 MHz bandwidth at 16 Bit. One is nearly enough for downlink in GSM-900, if you want uplink too, you need another USRP2. GSM-1800 is a much wider band and depending on the country, you might need to record the whole band to cover all possible hopping ARFCNs. Another question is what you do with the huge amount of data, here a GPU can help. > If sniffing bidirectional, you will need two of them, right. Yes. > Or you manage to mix the uplink channels you are intersted in into the > downlink band you record. > But thats quite epxerimental and depends on channel usage :) > May work at home, but not everywhere. But this would mean a custom RF-board, right ? Best regards, Dieter -- Dieter Spaar, Germany [email protected] _______________________________________________ A51 mailing list [email protected] http://lists.lists.reflextor.com/cgi-bin/mailman/listinfo/a51
