Eric Blossom wrote:
For now, don't worry about getting it into dB on the FPGA.
The representation can be manipulated on the host.
OK, so how do I get post-ADC rssi out of the USRP for any arbitrary
daughtercard?
My radio astronomy receiver could benefit from this, especially if the
RSSI is
On Thu, Aug 16, 2007 at 12:36:05PM -0400, George Nychis wrote:
Okay, so I'm a little bit intimidated, I'm not too familiar at this level.
So I'm going to ask for some help me through with baby step questions :)
We managed to get reading/writing to some unused registers working
through
George Nychis wrote:
We want to compute the RSSI in dB on the FPGA, we're not even
interested in the FPGA responding back with the RSSI at this point.
Okay, but--why do you need units of dB? This is in the log domain, so
at some point on the FPGA you'll need to take a logarithm of an
Eric, we want feedback from you on this one :)
I think you're right Jonathan, for performing carrier sense in the FPGA,
we really do not need it in dB. Calculating the average to determine a
threshold will get the job done with less the hassle. And right, if the
host really wants it in dB,
PS. We have a hacked up version of carrier sense working right now :)
We're just using the C/S read register method to get a couple RSSI
readings, computing an average, then writing the threshold to a register
on the FPGA.
The packets are then marked with a carrier sense flag, which we
George Nychis wrote:
I think you're right Jonathan, for performing carrier sense in the
FPGA, we really do not need it in dB. Calculating the average to
determine a threshold will get the job done with less the hassle.
You may want to implement two thresholds, one for rising power and one
Zhuocheng Yang wrote:
Hi guys:
I noticed that in the adc_interface, there are registers called rssi_0,
rssi_1, rssi_2, and rssi_3. All of which are 32 bits. However, according to
the header format:
http://gnuradio.org/trac/browser/gnuradio/trunk/usrp/doc/inband-signaling-usb
The rssi
There are many forms of RSSI measurement between the daughterboards and
FPGA.
The RFX900, 1200, 1800, and 2400 (but not the 400) have analog RSSI
measurement at baseband. By reading one of the low speed ADCs in the
9862 you can get the signal level at baseband. To translate that to an
RF
Hi guys:
I noticed that in the adc_interface, there are registers called rssi_0, rssi_1,
rssi_2, and rssi_3. All of which are 32 bits. However, according to the header
format:
http://gnuradio.org/trac/browser/gnuradio/trunk/usrp/doc/inband-signaling-usb
The rssi should be 6 bits. Do I just use
On 8/7/07, Zhuocheng Yang [EMAIL PROTECTED] wrote:
Hi guys:
I noticed that in the adc_interface, there are registers called rssi_0,
rssi_1, rssi_2, and rssi_3. All of which are 32 bits. However, according to
the header format:
Brian Padalino wrote:
Is this really the RSSI - or should the RSSI actually be a function of
the amount of gain or attenuation in the RF stages? I am sure it gets
pretty difficult calculating an estimate for the amount of power at
the antenna.
It's a digital RSSI value, meaning it's based
On 8/7/07, Johnathan Corgan [EMAIL PROTECTED] wrote:
It's a digital RSSI value, meaning it's based on the output of the ADC
and not the true RF power at the antenna. Furthermore, it's really a
single pole low pass averaging filter on the absolute value of the ADC
value, with no way to adjust
Brian Padalino wrote:
I haven't taken a look at the daughterboards, but do they all use
different amplifiers and different numbers of stages?
They are mostly different. All the RFX boards are similar, but the RFX
uses a different front end from the TVRX, DBSRX and the new boards still
in
Johnathan Corgan wrote:
Brian Padalino wrote:
I haven't taken a look at the daughterboards, but do they all use
different amplifiers and different numbers of stages?
They are mostly different. All the RFX boards are similar, but the RFX
uses a different front end from the TVRX, DBSRX and
14 matches
Mail list logo
