Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-03 Thread Marcus Müller
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Khalid, > rather than having a standalone USB connection to the computer, is > there anyway to piggyback the temperature data from the temp sensor > onto the digital interface to the FPGA board of the N200? That's what you would do if you attac

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-03 Thread khalid.el-darymli
Thank you Ralph and Marcus for this information. That is so helpful. One final question on this, rather than having a standalone USB connection to the computer, is there anyway to piggyback the temperature data from the temp sensor onto the digital interface to the FPGA board of the N200? Thank yo

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-02 Thread Ralph A. Schmid, dk5ras
In my job we have learned that lesson and fitted on all our DSP systems (you could call them direct digitizing SDRs, although we do not radio stuff) a cheap I2C temperature sensor. No big thing by means of software, costs and PCB space, but already proved being very useful. Could be considered f

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-02 Thread Marcus D. Leech
On 12/02/2014 10:36 AM, Marcus Müller wrote: Ok, three things: 1. there are daughterboards with temperature sensors; search for temperature in http://files.ettus.com/manual/page_dboards.html (I think it's tvrx2) I had forgotten that the TVRX2 had an on-board temperature sensor. It's the only

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-02 Thread Marcus Müller
Ok, three things: 1. there are daughterboards with temperature sensors; search for temperature in http://files.ettus.com/manual/page_dboards.html (I think it's tvrx2) 2. there are auxiliary ADCs. If you use a daughterboard that exposes these pins, you can use them with a PTC or something equivalen

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-02 Thread Marcus D. Leech
On 12/02/2014 10:06 AM, khalid.el-darymli wrote: Hi Marcus, Is there a temperature sensor on-board the N200 unit? If not, does it support installing any such sensor? Thanks. No, and no. But there are a tonne of USB-based temperature sensors out there. Google is your friend, etc. Bes

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-12-02 Thread khalid.el-darymli
Hi Marcus, Is there a temperature sensor on-board the N200 unit? If not, does it support installing any such sensor? Thanks. Best regards, Khalid On Fri, Nov 28, 2014 at 5:44 PM, Marcus D. Leech wrote: > On 11/28/2014 03:41 PM, khalid.el-darymli wrote: > > > > Back to my original question,

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-11-28 Thread Marcus D. Leech
On 11/28/2014 03:41 PM, khalid.el-darymli wrote: Back to my original question, what should I do to correct for this? Thanks in advance. Best, Khalid Khalid: Thanks very much for the very-extensive data. My main concern, as one of the Ettus support team, was that there was something wron

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-11-28 Thread mleech
What is the magnitude of the frequency drift? What is the magnitude of the gain drift? What are you measuring backscatter *from*? On 2014-11-28 10:14, khalid.el-darymli via USRP-users wrote: > Hi, > > Given a set of synced _(i.e., using external GPS REF/PPS)_, time-commanded > and cali