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Today's Topics:
1. Re: Reference Clock (hossein talaiee via USRP-users)
2. Re: Reference Clock (Marcus D. Leech via USRP-users)
3. Re: Reference Clock (Matt Ettus via USRP-users)
4. USRP B210 Board Mounted GPSDO (Knee, Peter A via USRP-users)
5. Re: USRP B210 Board Mounted GPSDO (Marcus D. Leech via USRP-users)
6. UHDN210: FPGA errors even when timing is satisfied
(mahaveer gupta via USRP-users)
7. Re: [EXTERNAL] Re: USRP B210 Board Mounted GPSDO
(Knee, Peter A via USRP-users)
8. Re: Reference Clock (hossein talaiee via USRP-users)
9. Re: Reference Clock (Ian Buckley via USRP-users)
10. Re: [EXTERNAL] Re: USRP B210 Board Mounted GPSDO
(Marcus D. Leech via USRP-users)
11. Mis-aligned data on B210 RX channels
(Robert Kossler via USRP-users)
12. Agenda Announcement/GRCon14 Update (John Malsbury via USRP-users)
13. Re: question about GPSDO module (Matt Ettus via USRP-users)
14. Re: New to USRP :: software development platform
recommendations sought (zeng)
15. Re: New to USRP :: software development platform
recommendations sought (Ethem Sozer via USRP-users)
----------------------------------------------------------------------
Message: 1
Date: Wed, 7 May 2014 20:56:35 +0430
From: hossein talaiee via USRP-users <[email protected]>
To: Ian Buckley <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] Reference Clock
Message-ID:
<CAAiBEBSzbXbMHx5QtzS-ppmMEUx=uHnYMtLRJmXuZ8vuKcTS=w...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
I'm using USRP N210 ! And the issue is I'm using a clock source that can't
generate 10MHz without lots of jitter!
On Wed, May 7, 2014 at 10:35 AM, Ian Buckley <[email protected]> wrote:
> What is the issue you foresee with 10MHz as a reference clock and for
> which USRP product?
>
> On May 6, 2014, at 10:19 PM, Hossein Talaiee via USRP-users <
> [email protected]> wrote:
>
> > Hi
> >
> > Is there anyway to use another reference frequency instead of 10 MHz?
> Like 8 or 12 MHz, not multiple of 10MHz!
> >
> > _______________________________________________
> > USRP-users mailing list
> > [email protected]
> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
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Message: 2
Date: Wed, 07 May 2014 12:31:11 -0400
From: "Marcus D. Leech via USRP-users" <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] Reference Clock
Message-ID: <[email protected]>
Content-Type: text/plain; charset="utf-8"; Format="flowed"
On 05/07/2014 12:26 PM, hossein talaiee via USRP-users wrote:
> I'm using USRP N210 ! And the issue is I'm using a clock source that
> can't generate 10MHz without lots of jitter!
>
>
I'll point out that OCXOs at 10Mhz are routinely available cheaply on
eBay and other places. It's not that hard, really to find
a stable, high-quality 10Mhz reference that is better than the
already-quite-good reference on the USRP devices themselves.
>
> On Wed, May 7, 2014 at 10:35 AM, Ian Buckley <[email protected]
> <mailto:[email protected]>> wrote:
>
> What is the issue you foresee with 10MHz as a reference clock and
> for which USRP product?
>
> On May 6, 2014, at 10:19 PM, Hossein Talaiee via USRP-users
> <[email protected] <mailto:[email protected]>>
> wrote:
>
> > Hi
> >
> > Is there anyway to use another reference frequency instead of 10
> MHz? Like 8 or 12 MHz, not multiple of 10MHz!
> >
> > _______________________________________________
> > USRP-users mailing list
> > [email protected] <mailto:[email protected]>
> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
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Message: 3
Date: Wed, 7 May 2014 18:36:28 +0200
From: Matt Ettus via USRP-users <[email protected]>
To: hossein talaiee <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] Reference Clock
Message-ID:
<CAN=1kn8wnjmddo+q88fsbvi_awcapgk7voymd9cna2ou0z0...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
You can reprogram the N210 to handle other reference frequencies by
changing the N and R dividers. 8 or 12 MHz should both be fine. You'll
need to make the changes to UHD
Matt
On Wed, May 7, 2014 at 6:26 PM, hossein talaiee via USRP-users <
[email protected]> wrote:
> I'm using USRP N210 ! And the issue is I'm using a clock source that can't
> generate 10MHz without lots of jitter!
>
>
> On Wed, May 7, 2014 at 10:35 AM, Ian Buckley <[email protected]> wrote:
>
>> What is the issue you foresee with 10MHz as a reference clock and for
>> which USRP product?
>>
>> On May 6, 2014, at 10:19 PM, Hossein Talaiee via USRP-users <
>> [email protected]> wrote:
>>
>> > Hi
>> >
>> > Is there anyway to use another reference frequency instead of 10 MHz?
>> Like 8 or 12 MHz, not multiple of 10MHz!
>> >
>> > _______________________________________________
>> > USRP-users mailing list
>> > [email protected]
>> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
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Message: 4
Date: Wed, 7 May 2014 17:00:56 +0000
From: "Knee, Peter A via USRP-users" <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] USRP B210 Board Mounted GPSDO
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
Hi all,
I've got a question regarding the use of the board mounted GPSP (TCXO) for the
B210. We have an application that requires precision time-stamping for Rx.
Previously, using the N210 and an external GPS receiver, we've used the PPS
signal from the receiver to set the time within the FPGA to the correct GPS
time. We use the GPS receiver as an NTP server to ensure our system time is
accurate to within a second of GPS time.
We would like to get away from having a large power hungry external GPS
receiver but we still need all this functionality. Obviously the GPSDO will
provide the necessary PPS and 10 MHz reference for the B210. My question has
to do with setting the time in the FPGA. I've seen it briefly mentioned but
wanted to be sure. Is there a method through the UHD to have the time be
correctly set to GPS time within the FPGA? Our software can then request the
device to start streaming sometime in the future and use the supplied
time-stamps to identify signal sample times.
Any insight anyone can provide would be appreciated.
Thanks,
Peter Knee
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Message: 5
Date: Wed, 07 May 2014 13:05:01 -0400
From: "Marcus D. Leech via USRP-users" <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] USRP B210 Board Mounted GPSDO
Message-ID: <[email protected]>
Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
On 05/07/2014 01:00 PM, Knee, Peter A via USRP-users wrote:
>
> Hi all,
>
> I've got a question regarding the use of the board mounted GPSP (TCXO)
> for the B210. We have an application that requires precision
> time-stamping for Rx. Previously, using the N210 and an external GPS
> receiver, we've used the PPS signal from the receiver to set the time
> within the FPGA to the correct GPS time. We use the GPS receiver as
> an NTP server to ensure our system time is accurate to within a second
> of GPS time.
>
> We would like to get away from having a large power hungry external
> GPS receiver but we still need all this functionality. Obviously the
> GPSDO will provide the necessary PPS and 10 MHz reference for the
> B210. My question has to do with setting the time in the FPGA. I've
> seen it briefly mentioned but wanted to be sure. Is there a method
> through the UHD to have the time be correctly set to GPS time within
> the FPGA? Our software can then request the device to start streaming
> sometime in the future and use the supplied time-stamps to identify
> signal sample times.
>
> Any insight anyone can provide would be appreciated.
>
> Thanks,
>
> Peter Knee
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
Yes, the API is the same as for N210 with an on-board GPS.
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
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Message: 6
Date: Wed, 7 May 2014 12:19:11 -0500
From: mahaveer gupta via USRP-users <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] UHDN210: FPGA errors even when timing is
satisfied
Message-ID:
<camhwhyzdfe0rvfq+jswbk+s8hzqwjnurnr7o0wmmsygwtsx...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Hello,
I made simple changes to the UHD N210 FPGA code.
I added a correlator that intercepts samples coming from ddc chain,
correlates and sends the results to the host. The change was introduced in
dsp_rx_glue.v
The correlator does not work as expected and gives random high valued
outputs for magnitude of correlation.
I use Xilinx 14.1 ISE and all default timing constraints in u2plus.ucf have
been satisfied. I also added another constraint based on ddc_out_strobe
which was being used by the correlator, still the correlator gives wrong
outputs.
Please let me know if you have a suggestion here
--
Thanks,
M
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Message: 7
Date: Wed, 7 May 2014 17:33:45 +0000
From: "Knee, Peter A via USRP-users" <[email protected]>
To: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] [EXTERNAL] Re: USRP B210 Board Mounted
GPSDO
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
Thanks Marcus! Just wanted to verify.
According to the internal GPSDO application notes, if the USRP detects the
GPSDO at startup, it will be configured to use it as the frequency and time
reference, using the internal VITA timestamp to initialize to GPS time when it
is locked to satellites. Does the firmware continuously monitor the gps_locked
sensor in order to initialize the time or is that done somehow through the UHD?
Obviously when the device is first powered on, the GPSDO will not be locked to
satellites so I'd like to have software monitor the sensor and initialize the
time myself if that is necessary.
Thanks,
Peter Knee
From: USRP-users [mailto:[email protected]] On Behalf Of
Marcus D. Leech via USRP-users
Sent: Wednesday, May 07, 2014 11:05 AM
To: [email protected]
Subject: [EXTERNAL] Re: [USRP-users] USRP B210 Board Mounted GPSDO
On 05/07/2014 01:00 PM, Knee, Peter A via USRP-users wrote:
Hi all,
I've got a question regarding the use of the board mounted GPSP (TCXO) for the
B210. We have an application that requires precision time-stamping for Rx.
Previously, using the N210 and an external GPS receiver, we've used the PPS
signal from the receiver to set the time within the FPGA to the correct GPS
time. We use the GPS receiver as an NTP server to ensure our system time is
accurate to within a second of GPS time.
We would like to get away from having a large power hungry external GPS
receiver but we still need all this functionality. Obviously the GPSDO will
provide the necessary PPS and 10 MHz reference for the B210. My question has
to do with setting the time in the FPGA. I've seen it briefly mentioned but
wanted to be sure. Is there a method through the UHD to have the time be
correctly set to GPS time within the FPGA? Our software can then request the
device to start streaming sometime in the future and use the supplied
time-stamps to identify signal sample times.
Any insight anyone can provide would be appreciated.
Thanks,
Peter Knee
_______________________________________________
USRP-users mailing list
[email protected]<mailto:[email protected]>
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
Yes, the API is the same as for N210 with an on-board GPS.
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
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Message: 8
Date: Wed, 7 May 2014 22:12:58 +0430
From: hossein talaiee via USRP-users <[email protected]>
To: Matt Ettus <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] Reference Clock
Message-ID:
<caaibebs2efq0qdb090oavrdbxryjwoqy4gtap_ukz9zqnpw...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Where are N and R ? Where should I change?
Can you point me to the where should I change!??
On Wed, May 7, 2014 at 9:06 PM, Matt Ettus <[email protected]> wrote:
>
> You can reprogram the N210 to handle other reference frequencies by
> changing the N and R dividers. 8 or 12 MHz should both be fine. You'll
> need to make the changes to UHD
>
> Matt
>
>
> On Wed, May 7, 2014 at 6:26 PM, hossein talaiee via USRP-users <
> [email protected]> wrote:
>
>> I'm using USRP N210 ! And the issue is I'm using a clock source that
>> can't generate 10MHz without lots of jitter!
>>
>>
>> On Wed, May 7, 2014 at 10:35 AM, Ian Buckley <[email protected]>wrote:
>>
>>> What is the issue you foresee with 10MHz as a reference clock and for
>>> which USRP product?
>>>
>>> On May 6, 2014, at 10:19 PM, Hossein Talaiee via USRP-users <
>>> [email protected]> wrote:
>>>
>>> > Hi
>>> >
>>> > Is there anyway to use another reference frequency instead of 10 MHz?
>>> Like 8 or 12 MHz, not multiple of 10MHz!
>>> >
>>> > _______________________________________________
>>> > USRP-users mailing list
>>> > [email protected]
>>> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>>
>>>
>>
>> _______________________________________________
>> USRP-users mailing list
>> [email protected]
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>
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Message: 9
Date: Wed, 7 May 2014 10:52:06 -0700
From: Ian Buckley via USRP-users <[email protected]>
To: hossein talaiee <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] Reference Clock
Message-ID: <[email protected]>
Content-Type: text/plain; charset="us-ascii"
uhd/host/lib/usrp/usrp2/clock_control.cpp
You should probably study page 5 of the N210 schematics and the AD9510 data
sheet first also. That should answer your questions about the N and R dividers.
-Ian
On May 7, 2014, at 10:42 AM, hossein talaiee <[email protected]> wrote:
> Where are N and R ? Where should I change?
> Can you point me to the where should I change!??
>
>
>
> On Wed, May 7, 2014 at 9:06 PM, Matt Ettus <[email protected]> wrote:
>
> You can reprogram the N210 to handle other reference frequencies by changing
> the N and R dividers. 8 or 12 MHz should both be fine. You'll need to make
> the changes to UHD
>
> Matt
>
>
> On Wed, May 7, 2014 at 6:26 PM, hossein talaiee via USRP-users
> <[email protected]> wrote:
> I'm using USRP N210 ! And the issue is I'm using a clock source that can't
> generate 10MHz without lots of jitter!
>
>
> On Wed, May 7, 2014 at 10:35 AM, Ian Buckley <[email protected]> wrote:
> What is the issue you foresee with 10MHz as a reference clock and for which
> USRP product?
>
> On May 6, 2014, at 10:19 PM, Hossein Talaiee via USRP-users
> <[email protected]> wrote:
>
> > Hi
> >
> > Is there anyway to use another reference frequency instead of 10 MHz? Like
> > 8 or 12 MHz, not multiple of 10MHz!
> >
> > _______________________________________________
> > USRP-users mailing list
> > [email protected]
> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
>
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Message: 10
Date: Wed, 07 May 2014 14:02:52 -0400
From: "Marcus D. Leech via USRP-users" <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] [EXTERNAL] Re: USRP B210 Board Mounted
GPSDO
Message-ID: <[email protected]>
Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
On 05/07/2014 01:33 PM, Knee, Peter A via USRP-users wrote:
>
> Thanks Marcus! Just wanted to verify.
>
> According to the internal GPSDO application notes, if the USRP detects
> the GPSDO at startup, it will be configured to use it as the frequency
> and time reference, using the internal VITA timestamp to initialize to
> GPS time when it is locked to satellites. Does the firmware
> continuously monitor the gps_locked sensor in order to initialize the
> time or is that done somehow through the UHD?
>
> Obviously when the device is first powered on, the GPSDO will not be
> locked to satellites so I'd like to have software monitor the sensor
> and initialize the time myself if that is necessary.
>
> Thanks,
>
> Peter Knee
>
The UHD startup code detects the presence of a GPS, and "does the right
thing". Power the device up, wait an hour, then establish a session to it.
>
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
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Message: 11
Date: Wed, 7 May 2014 17:28:14 -0400
From: Robert Kossler via USRP-users <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] Mis-aligned data on B210 RX channels
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
I am using a B210 to collect data from 2 RX channels simultaneously and saving
the results to file (using a modified program based on "rx_samples_to_file").
As a test, I injected a multi-tone signal (400 tones evenly spaced across 20
MHz) into both RX ports using a 1:2 splitter. I then computed FFTs and
compared the relative magnitude and phase of each tone between the two
channels. The magnitude was nearly equal as expected. But, the phase has a
linear drift with frequency. During one capture, the relative phase between
adjacent tones (tone spacing of 50 kHz) was 79 degrees. But, the phase slope is
not constant from capture to capture.
For the capture where I measured 79 degrees between adjacent tones, I
calculated that this amount of linear phase versus frequency corresponds to a
channel-to-channel time delay of about 4.39 us, which in turn corresponds to
about 110 samples at my sampling rate of 25 MS/s. Indeed, when I purposely
shift one of the channels by 110 samples, the linear phase versus frequency
disappears.
I am wondering if anyone has seen similar behavior. I fully expect that the
problem is some type of configuration problem or some problem in interpreting /
saving the incoming data streams but I can't seem to find it.
Attached is my "rx_samples_to_file_2" code which is a combination of the
"rx_samples_to_file" and "benchmark_rate" examples programs.
Rob Kossler
------------------------------
Message: 12
Date: Wed, 7 May 2014 20:43:10 -0700
From: John Malsbury via USRP-users <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] Agenda Announcement/GRCon14 Update
Message-ID:
<CAN5WegSj9DBXAaOzmaR7GY2+3E=z85xnlbljtcurhfey+4n...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Greetings,
It's been a few weeks since our last update on GRCon14. Here's the latest:
*Conference Agenda is Posted*
I am happy and proud to announce that the agenda for GNU Radio Conference
2014 has been posted. We received an variety of great, high-quality
proposals on topics ranging from wireless security to satellite
communications and networking. Tom Rondeau and Michael Dickens spent a
great deal of time sorting through the presentations and assembling an
agenda that is packed full of interesting and educational content. While
some minor details may change, you can find an up-to-date agenda at the
following link. If you are a presenter and need to modify your entry,
please contact Michael Dickens to do so.
http://gnuradio.squarespace.com/grcon14-agenda/
*Help Promote GNU Radio Conference*
On another note its worth mentioning that we have been keeping a pulse on
registration. Based on the current run rate, we believe that this is going
to be *the largest* GNU Radio conference, *by far*.
With the conference agenda assembled and great forward momentum, we would
like to ask this awesome community to help us promote this event. GRCon14
is on the verge of becoming one of the largest and most influential events
with a focus on SDR and wireless implementation. With a community-driven
effort, we could really put ourselves on the map this year and generate
even more excitement with potential users and developers.
Whether you simply remind your fellow GNU Radio developer, or invite
someone new to join us for this event, we think your enthusiasm for the
event is the thing that will make the difference.
*Register for the Event*
If you would like to register for GRCon14, follow this link:
http://grcon14.eventbrite.com/
*We look forward to seeing you in September!*
Best Regards,
John Malsbury
GNU Radio Conference Chair
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Message: 13
Date: Thu, 8 May 2014 10:28:39 +0200
From: Matt Ettus via USRP-users <[email protected]>
To: fquitin <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] question about GPSDO module
Message-ID:
<CAN=1kn_+Vtc=bkkksp6ajce9zxwftku1zlchjn6w6ht20y1...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Francois,
The module will adjust its control voltage over time based on temperature
and according to its model for crystal aging. So it will try to remain as
accurate as possible.
Matt
On Wed, May 7, 2014 at 9:53 AM, fquitin <[email protected]> wrote:
> Linear drift in time (with of course a slowly varying frequency error).
> The main thing I want to avoid is digital corrections in the holdover mode,
> as this cannot be predicted by any type of LO model.
>
> Francois
>
>
> On 07.05.2014 09:49, Matt Ettus wrote:
>
>> Linear drift in frequency or linear drift in time? Linear drift in
>> time is given by a roughly constant frequency error. Frequency error
>> will change slowly over time, but it will be random. Also, there
>> might be digital correction during the holdover period, but I am not
>> certain. I will try to find out.
>>
>> Matt
>>
>> On Wed, May 7, 2014 at 9:42 AM, fquitin <[email protected]> wrote:
>>
>> Hi Matt,
>>>
>>> Thanks for the answer. And in this "holdover mode", there is no more
>>> correction of the clock, right? (I need the oscillator to have predictable
>>> behavior, e.g. more or less linear drift without any digital corrections)
>>>
>>> Francois
>>>
>>> On 07.05.2014 09:28, Matt Ettus wrote:
>>>
>>> If you allow the GPSDO to lock and sit for a while, and then remove
>>>> the antenna, it should go into "holdover mode". This will maintain
>>>> more accuracy than if you had not had GPS to start with, but obviously
>>>> not as good as if you had kept the antenna attached. If you remove
>>>> power and power up again you lose the holdover performance and go into
>>>> normal free-run.
>>>>
>>>> Matt
>>>>
>>>> On Tue, May 6, 2014 at 9:46 AM, Francois Quitin via USRP-users
>>>> <[email protected]> wrote:
>>>>
>>>> Dear all,
>>>>>
>>>>>
>>>>>
>>>>> A little question about the GPSDO-module disciplined local oscillator.
>>>>> We have run an experiment where we connect a GPS antenna to the GPSDO
>>>>> module, and let the GPSDO acquire enough satellites to achieve a lock
>>>>> (this
>>>>> is to align the time of different USRPs). We then disconnect the GPS
>>>>> antenna, and let the local oscillator run by itself.
>>>>>
>>>>>
>>>>>
>>>>> After disconnecting the GPS antenna, will the local oscillator behave
>>>>> like any oscillator, or will there be some lingering effect from the GPSDO
>>>>> module GPS correction?
>>>>>
>>>>>
>>>>>
>>>>> Thanks a lot,
>>>>>
>>>>> Francois
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>>
>>>>> Francois Quitin, Ph.D.
>>>>>
>>>>>
>>>>>
>>>>> Research Fellow
>>>>>
>>>>> INFINITUS - Infocomm Centre of Excellence
>>>>>
>>>>> School of EEE, Nanyang Technological University
>>>>>
>>>>> 50 Nanyang Ave, S2-B4b-05
>>>>> Singapore 639798
>>>>>
>>>>> Phone: +65-8502-3690 [1] [1]
>>>>>
>>>>>
>>>>> Email: [email protected]
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> USRP-users mailing list
>>>>> [email protected]
>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com[2] [2]
>>>>>
>>>>
>>>> Links:
>>>> ------
>>>> [1] tel:%2B65-8502-3690
>>>> [2] http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com[2]
>>>>
>>>
>>
>>
>> Links:
>> ------
>> [1] tel:%2B65-8502-3690
>> [2] http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>
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------------------------------
Message: 14
Date: Thu, 8 May 2014 10:14:06 +0000 (UTC)
From: zeng,xw via USRP-users <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] New to USRP :: software development platform
recommendations sought
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
Ethem Sozer via USRP-users <usrp-users@...> writes:
>
> Hi Zeng,
> You can use MATLAB with USRP directly using the USRP Support Package,
which lets you receive or transmit
> signals in real-time or in batch mode.
> Regards,
> Ethem
>
> -----Original Message-----
> From: USRP-users [mailto:usrp-users-bounces@...] On Behalf
> Of zeng, xuewen via USRP-users
> Sent: Thursday, May 01, 2014 11:34 PM
> To: usrp-users@...
> Subject: Re: [USRP-users] New to USRP :: software development platform
recommendations sought
>
> We did similar experiments you may want to do: combine matlab baseband
signal processing with usrp real
> wolrd tranceiving. Matlab is used to generate baseband IQ data file with
added noise, freq-offset &
> multi-path effects and up-sampling-pulse shaping filter, then tranceiving
thru
> gnuradio+usrp and then back to matlab to proc the rxed baseband IQ data
> file. We used DIY usrp1 and gnuradio 3.2.2. We modified
usrp_standard_tx.cpp to tx the IQ data file and used
> usrp_rx_cfile cmdlinee tool to save rxed int16 iq data to file. We need
to locate the start of a frame by
> preample sync process.(ref: Frame synchronization in SC-FDE system using
PN sequence modulation in
> Ieee explore, url:
> http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6197855&url=http%3A%
> 2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6197855)
> This experiment provides a low cost real world trx validation routine.
>
> It also should be noted that RFX 900/2400 will add noticable extra noise
and freq-offset. BasicRX/TX F
> transceiving maybe used to eval the matlab baseband proc.
> I am wondering if Uhd based usrp-gnuradio or matlab provide ready tools
for baseband IQ file trx
> experiment. Any info on this would be appreciated.
>
> zeng,xuewen from zxwdsp (at) 126.ocm.
>
> _______________________________________________
> USRP-users mailing list
> USRP-users@...
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
Thansk Ethem.
I am using USRP1 and mathworks web-site says the usrp package has been
tested with N210 and usrp2. Any idea about if the pkg works with usrp1?
regards.
zeng,xuewen from zxwdsp (at) 126.com
------------------------------
Message: 15
Date: Thu, 8 May 2014 12:57:26 +0000
From: Ethem Sozer via USRP-users <[email protected]>
To: "zeng,xw" <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] New to USRP :: software development platform
recommendations sought
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
Currently Ethernet connected ones (i.e. N2xx and USRP2) are supported..
Ethem
-----Original Message-----
From: USRP-users [mailto:[email protected]] On Behalf Of
zeng,xw via USRP-users
Sent: Thursday, May 08, 2014 6:14 AM
To: [email protected]
Subject: Re: [USRP-users] New to USRP :: software development platform
recommendations sought
Ethem Sozer via USRP-users <usrp-users@...> writes:
>
> Hi Zeng,
> You can use MATLAB with USRP directly using the USRP Support Package,
which lets you receive or transmit
> signals in real-time or in batch mode.
> Regards,
> Ethem
>
> -----Original Message-----
> From: USRP-users [mailto:usrp-users-bounces@...] On Behalf Of zeng,
> xuewen via USRP-users
> Sent: Thursday, May 01, 2014 11:34 PM
> To: usrp-users@...
> Subject: Re: [USRP-users] New to USRP :: software development platform
recommendations sought
>
> We did similar experiments you may want to do: combine matlab baseband
signal processing with usrp real
> wolrd tranceiving. Matlab is used to generate baseband IQ data file
> with
added noise, freq-offset &
> multi-path effects and up-sampling-pulse shaping filter, then
> tranceiving
thru
> gnuradio+usrp and then back to matlab to proc the rxed baseband IQ
> gnuradio+data
> file. We used DIY usrp1 and gnuradio 3.2.2. We modified
usrp_standard_tx.cpp to tx the IQ data file and used
> usrp_rx_cfile cmdlinee tool to save rxed int16 iq data to file. We
> need
to locate the start of a frame by
> preample sync process.(ref: Frame synchronization in SC-FDE system
> using
PN sequence modulation in
> Ieee explore, url:
> http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6197855&url=http
> %3A%
> 2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6197855)
> This experiment provides a low cost real world trx validation routine.
>
> It also should be noted that RFX 900/2400 will add noticable extra
> noise
and freq-offset. BasicRX/TX F
> transceiving maybe used to eval the matlab baseband proc.
> I am wondering if Uhd based usrp-gnuradio or matlab provide ready
> tools
for baseband IQ file trx
> experiment. Any info on this would be appreciated.
>
> zeng,xuewen from zxwdsp (at) 126.ocm.
>
> _______________________________________________
> USRP-users mailing list
> USRP-users@...
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
Thansk Ethem.
I am using USRP1 and mathworks web-site says the usrp package has been tested
with N210 and usrp2. Any idea about if the pkg works with usrp1?
regards.
zeng,xuewen from zxwdsp (at) 126.com
_______________________________________________
USRP-users mailing list
[email protected]
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
------------------------------
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------------------------------
End of USRP-users Digest, Vol 45, Issue 8
*****************************************
