On 12/21/2018 12:04 PM, Brian Padalino via USRP-users wrote:
On Fri, Dec 21, 2018 at 11:49 AM David Bengtson
<[email protected] <mailto:[email protected]>> wrote:
So I dug into this (On a 10k piece of equipment?) and came up with the
following bands
1: 3000 to 6000
2: 2200 to 2800
3: 1650 to 2200
4: 1400 to 1575
5: 700 to 1000
6: 500 to 530
plus 1 unfiltered path.
Also looks like the web datasheet has some information, though it may
be slightly different than what you found (page 3 of the PDF):
https://www.ettus.com/content/files/USRP_N300_Datasheet_V4_Web.pdf
Below 500 MHz, there's an 84 MHz passband based the up-conversion
stage there.
This seems like an unusual collection of passbands, in addition to
having big gaps between filter passbands.
I'm curious is someone from Ettus could comment on the design intent
behind this selection.
I'm also curious to know if these passbands have been swept with a
Network analyzer to see if there's any untoward
interaction between the highpass/lowpass filter structures used to
derive the bandpass characteristics
It would be nice to have those sweeps similar to what is published on
the E310 product page:
https://www.ettus.com/content/USRP_E3xx_RX_Filter_Graph_Web.png
https://www.ettus.com/content/USRP_E3xx_TX_Filter_Graph_Web.png
Maybe the E310 and N310 share similar Minicircuits filters placed back
to back?
Brian
I'll comment that no matter what "line-up" you use for a filterbank,
it'll be "wrong" for some applications. You simply cannot choose
"cuts" that will work for every application.
Technology and physics haven't yet delivered up a multi-octave tunable
filter with variable bandwidth, etc, etc. So, you either leave out
filters altogether, assuming that the end-user will put in something
appropriate to your application, or you try to "guess" at a configuration
that covers some predicted fraction of your user community, and then
provide a "through" path for everything else.
_______________________________________________
USRP-users mailing list
[email protected]
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
