10 bit samples

GNU Radio
1

Hi everybody,
Just a very simple question:
Is it possible to obtain 10 bit samples out of USRP (either 1 or 2) by
using
suitable libusrp primitives / parameters?

I mean having 10 bit samples (instead of 16) already over USB / ETHERNET
so
that one can save bandwidth to be spent in attaining higher sampling
rates.

I just explored online documentation but was unable to determine this
with
sufficient confidence.

thank you

vince

2

On Wed, Aug 25, 2010 at 9:58 AM, Vincenzo P. [email protected]
wrote:

Hi everybody,
Just a very simple question:
Is it possible to obtain 10 bit samples out of USRP (either 1 or 2) by using
suitable libusrp primitives / parameters?

No. But you can produce 8-bit samples on the USRP1 by appropriately
setting the FR_RX_FORMAT register. You can set it through the standard
interface. This option is not available on the USRP2.

Thomas

3

Thank you Thomas (and Marcus)

for the replies. I’ve been using the 8 bit mode un the USRP1 a while ago
for
a different application. I was looking for a slightly higher precision.

I did not know that the usrp2 could not do the 8bit sampling. Thanks for
the
info.

Regards

Vince

2010/8/25 Thomas T. [email protected]

On Wed, Aug 25, 2010 at 9:58 AM, Vincenzo P. [email protected]
wrote:

Hi everybody,nd
Just a very simple question:
Is it possible to obtain 10 bit samples out of USRP (either 1 or 2) by
using
suitable libusrp primitives / parameters?

No. But you can produce 8-bit samples on the USRP1 by appropriately
setting the FR_RX_FORMAT register. You can set it through the standard
interface. This option is not available on the USRP2.

Thomas

4

On 08/26/2010 12:05 PM, Vincenzo P. wrote:

Regards

Vince

At one time, there were plans to implement a user-configurable “shift
and mask” approach to
bit precision on the USRP1 end, along with appropriate packing
routines, etc. But this never
happened, so there’s 16-bit and 8-bit, and nothing in between.

The changes require support in the USRP1 uController code, and the
support code on the Gnu Radio
end. While not that difficult, they’re not that trivial, either.

–
Marcus L.
Principal Investigator
Shirleys Bay Radio Astronomy Consortium