Is it possible to use a decimation factor smaller than 4 in the comm.SDRuReceiver System object?

Im planning to buy a USRP B200/B210 SDR Board.

According to the comm.SDRuReceiver System object documentation the decimation factor must be >= 4. This would lower the usable bandwidth of the USRP B200 to 56MHz/4=14MHz. According to the Hardware description it should be possible to receive the full 56MHz signal though. I was wondering if this is a documentation mistake or a software limitation?

Answer 1

[Linus Rüttimann]

I have tested myself in the meantime. It's possible to set a decimation factor smaller than 4 with the B200.

[sadegh]

Does it mean we can set bandwidth by this fotmula?

BW = MasterClockRate/DecimationFactor

Answer 2

[Walter Roberson]

Looking at http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/2012-September/005313.html it looks like the DAC has a minimum 4x interpolation (so 100 MSamp/s would become 400 MSamp/s), so the 4x decimation would be returning to the original speed, not reducing the bandwidth.