[Discuss-gnuradio] I can't find my USRP N200.

Hi, I am using USRP N200 with Ubuntu 12.04. This is my first experience for USRP. I installed GNU Radio and UHD according to http://www.sbrac.org/files/build-gnuradio. In the first try, I couldn’t find my USRP. But I could find it only when I power on i

Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

hi George, I noticed theses odd things several months ago. I am using USRP2s with XCVR2450. Since my UHD was upgraded to 003.004.000 or newer version, my USRP2s can't work in half duplex mode. When uhd_transmitter is instantiated later than uhd_receiver, tx works well but rx can't receive packets.

Re: [Discuss-gnuradio] I can't find my USRP N200.

Bejay, Try this documentation: http://files.ettus.com/uhd_docs/manual/html/usrp2.html#setup-networking In particular, make sure you have set the N200 to an IP address and netmask from which your computer can find it. You can use the "usrp2_recovery.py" script included with UHD to reset the N200

Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

On 06/18/2012 05:21 AM, King Qiu wrote: > hi George, > I noticed theses odd things several months ago. I am using USRP2s with > XCVR2450. Since my UHD was upgraded to 003.004.000 or newer version, my > USRP2s can't work in half duplex mode. When uhd_transmitter is > instantiated later than uhd_re

Re: [Discuss-gnuradio] Large Sample Spikes after Each Packet in tx_bursts Example

Hi All, "If you are seeing transients at the beginning of a burst, thats probablythe half band filters. They are implemented in block ram and dont clear between bursts." I'm actually sending one burst of a very long length so I can emulate an always-on signal (i.e. I'm not letting tx_bursts act

Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

> Thanks for the tip. I think I figured it out. > > The property to use an LO offset was true for TX and not RX. This would > mean that tuning an individual chain and using it would be fine; but > since there is a shared LO, the offset would not be compensated for by > the DSP on the chain in the

Re: [Discuss-gnuradio] Large Sample Spikes after Each Packet in tx_bursts Example

On 06/18/2012 10:51 AM, Jason Tran wrote: > Hi All, > > "If you are seeing transients at the beginning of a burst, thats > probablythe half band filters. They are implemented in block ram and > dont clear between bursts." > > I'm actually sending one burst of a very long length so I can emulate

Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

Hi Josh, Thanks a bunch for these pointers/patches and looking in to it! We are currently testing them out, shouldn't take long. However, we did verify that reverting to the older version (003.003.002) did work for us as it did for King (thanks!). Stay tuned... we'll let you know ASAP. - Georg

[Discuss-gnuradio] Announcing the LiveUSB SDR Environment

Ettus Research has released the LiveUSB SDR Environment - a 16 GB bootable USB 3.0 drive, which comes pre-installed with Ubuntu 11.10, UHD (USRP Hardware Driver), GNU Radio, OpenBTS, and associated documentation. The SDR Environment enables users to get up and running with the USRP product family q

Re: [Discuss-gnuradio] tunnel.py destination host unreachable

Weixian, Here is a temp solution, not sure it works or not: In the csma_mac.main_loop() of your tunnel.py, add a time_sleep(fixed_delay) right after the payload is read from the OS. You can set fixed_delay as 0.01 to 0.1 and test the result. And also, please set the CSMA threshold carefully to a

Re: [Discuss-gnuradio] gr-trellis convolutional coder FSM

Hello Achilleas, thanks for your reply, On Tuesday 12 June 2012 19:53:10 Achilleas Anastasopoulos wrote: > puncturing is not part of the FSM class. ok, thanks for the clarification, that caused the biggest confusion. > You can implement it as a simple memoryless device: > eg, if i want to punct

[Discuss-gnuradio] Basic question about filter

Hello everyone: You see in theory there should be a low-pass filter after ADC for eliminating the image. Also after DDC there should also be a filter. But in USRP there are not such things. So do the cic filter and half band filter implement that function besides decimation? Best regards___

Re: [Discuss-gnuradio] Basic question about filter

On 18/06/12 09:46 PM, signalswdm wrote: > Hello everyone: > You see in theory there should be a low-pass filter after ADC for > eliminating the image. Also after DDC there should also be a > filter. But in USRP there are not such things. So do the cic filter > and half band filter implement that fu

Re: [Discuss-gnuradio] Basic question about filter

On Jun 18, 2012, at 6:54 PM, Marcus D. Leech wrote: > On 18/06/12 09:46 PM, signalswdm wrote: >> >> Hello everyone: >>You see in theory there should be a low-pass filter after ADC for >> eliminating the image. Also after DDC there should also be a >> filter. But in USRP there are not such t

[Discuss-gnuradio] tunnel.py destination host unreachable - Temporarily solution, due to too fast reply!

Hello Josh, I have seen many guys complaining the tunnel.py failed in PING by the "destination host unreachable", for both the OFDM and Narrowband. This problem is caused by crushed ARP reply. I previously use the static ARP table to work round this problem, but today I did some investigating and

Re: [Discuss-gnuradio] Large Sample Spikes after Each Packet in tx_bursts Example

Hi All, After messing with the code, I think I figured out the problem. I think it's an issue of an underflow like Josh suggested. tx_waveforms works just fine for me when I send a constant signal (the spikes disappear). However, when I add some extra lines to the loop that populates "buff" an

Re: [Discuss-gnuradio] tunnel.py destination host unreachable - Temporarily solution, due to too fast reply!

I had a similar problem way back and found collided packets (corrupted packets with ok=False). I started digging and found that my gr_probe_mag_sqrd_X was not returning a high enough magnitude for the carrier sense to be tripped. This also had to do with an issue I was having getting the xcvr245

Re: [Discuss-gnuradio] Basic question about filter

Thank you To make it clear, I use USRP1. Does that mean in common the signals that come out of ADC chips (in USRP case it is the signals come out of AD9862 before processed in FPGA) is already filtered and aliasing prior is partly eliminated ? In the datasheet I do not see anything abou

Re: [Discuss-gnuradio] if uhd_transmitter instantiated after receiver, TX works, otherwise RX works

Your attached patch also fixes the problem! Thanks a bunch for helping narrow down this issue :) On Mon, Jun 18, 2012 at 3:59 PM, George Nychis wrote: > Hi Josh, > > Thanks a bunch for these pointers/patches and looking in to it! We are > currently testing them out, shouldn't take long. Howev

Re: [Discuss-gnuradio] tunnel.py destination host unreachable - Temporarily solution, due to too fast reply!

Jason, Thanks for information. If I am not wrong, I think your problem is from the CSMA threshold. In the single link case of my mail, A and B shoule always send packet at different time. In addition, I am using SBX board. The duplex detail is still devil for me. :< On Mon, Jun 18, 2012 at 11:1

Re: [Discuss-gnuradio] Basic question about filter

In general that is correct, analog filtering has been applied to the signal chain prior to the ADC to prevent significant spectral folding. Specifically, the individual radio daughter cards provide filters of appropriate bandwidth for each design, there is no analog filtering circuit in the actu