Installing GNU Radio and USRP

Hello all,

Today I write about installing GNU Radio on Linux and USRP.

GNU Radio Installation.

I am using Ubuntu 14.04, and I installed GNU Radio from two different sources:

From Ubuntu Repositories:

$ sudo apt-get install libboost-all-dev libusb-1.0-0-dev python-cheetah doxygen python-docutils
$ sudo apt-get install gnuradio

Ok, ok, I accept it is too easy. The problems with this is that Ubuntu repositories are not always up-to-date, as I was told by Ettus Support. So, I better installed from Ettus repositories, following the instructions given in the next link: http://code.ettus.com/redmine/ettus/projects/uhd/wiki/GNURadio_Linux

From Ettus:

sudo apt-get install python python-wxgtk2.8 pyqt4-dev-tools python-qwt5-qt4 python-numpy libboost-all-dev libusb-1.0.0-dev

sudo bash -c 'echo "deb http://files.ettus.com/binaries/uhd_stable/repo/uhd/ubuntu/`lsb_release -cs` `lsb_release -cs` main" > /etc/apt/sources.list.d/ettus.list'
sudo bash -c 'echo "deb http://files.ettus.com/binaries/uhd_stable/repo/gnuradio/ubuntu/`lsb_release -cs` `lsb_release -cs` main" >> /etc/apt/sources.list.d/ettus.list'
sudo apt-get update
sudo apt-get install -t `lsb_release -cs` uhd gnuradio

USRP

Once GNU Radio is installed, it is time to connect the USRP N210 to the computer using the Ethernet Cable. The default IP address of the USPR N210 is 192.168.10.2, so it is necessary to set an IP address for the host computer in the same network, in my case I set it to 192.168.10.1 with 255.255.255.0 as mask and 0.0.0.0. as Gateway. At first I made the mistake to put the IP address for the PC as 192.168.10.2 (the same as the USRP), of course I was able to pin from the command terminal but when trying to probe connection with it I always got the message:

Error: LookupError: KeyError: No devices found for ----->

Empty Device Address

With the USRP connected and the IP addresses correctly set, it is possible to test the device by typing:

$ uhd_usrp_probe

And you can expect to get this messages on the console (only the first lines are shown):

-- Opening a USRP2/N-Series device...
-- Current recv frame size: 1472 bytes
-- Current send frame size: 1472 bytes 

It happened to me that I a firmware upgrade was needed after the connection probe:

~$ uhd_usrp_probe

linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.007.002-release


-- Opening a USRP2/N-Series device...

Error: RuntimeError:

Please update the firmware and FPGA images for your device.

See the application notes for USRP2/N-Series for instructions.

Expected FPGA compatibility number 10, but got 9:

The FPGA build is not compatible with the host code build.

Please run:
sudo "/usr/lib/uhd/utils/uhd_images_downloader.py"

"/usr/lib/uhd/utils/usrp_n2xx_simple_net_burner" \
--addr="192.168.10.2"

So I ran the uhd_images_downlader.py. It happened that the GNU Radio version from the Ubuntu repositories was not able to perform the firmware upgrade, but with the version from Ettus worked just fine, it takes a couple of minutes and it ends with:

Image burning successful. Reset USRP (Y/n)? y

 Once it has rebooted and up again, it is possible to use again:

$ uhd_usrp_probe
linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.007.002-release

-- Opening a USRP2/N-Series device...
-- Current recv frame size: 1472 bytes
-- Current send frame size: 1472 bytes
...
...
...  

  

If you have further questions, let me know.

Thanks for reading.

Assembling USRP N210 hardware

In this entry I will show how to set up the USRP N210 hardware kit.

As advertised by Ettus, the USRP N210 kit contains:

• A USRP N210.
• 2 SMA-Bulkhead cables.
• Ethernet cable.
• Power Supply.

In our case we have 2 USRP N210 kits and also, we count with 2 SBX daugtherboards, which are designed to work on the frequency bands from 400 MHz up to 4.4 GHz

Here are a few photos taken while assembling the USRP N210:

Front view of the opened USRP.

Upper view of the USRP N210 with its SBX attached.

Front view of the already-assembled USRP N210.

If you need more info about assembling the USRP just check out this video, it is for USRP B210 but it is pretty much the same process for the USRP N210.

In a further entry I will write about setting up the USPR on GNU Radio.

Thanks.

USRP from Ettus

Hello,

I this entry I will write about USRP (Universal Serial Radio Peripheral) from the company Ettus Research. The intention of talking about USRP is due it is the hardware I am working with at this moment, it is not a commercial entry. USRP is only one of many recommended hardware peripherals by GNU Radio. Specifically I will write about USRP N210 kit. The basic idea of this kind of hardware it to be the front-end of our baseband signal processing waveforms in order to be transmitted over the air.

There are basically three series of USRP hardware:

1. Networked Series.
2. Serial Series.
3. Embedded Series.

The Networked Series connects the peripheral with its host computer using an Gigabit Ethernet interface. On its side, the Serial Series uses USB 2.0 and USB 3.0 as interface between host computer and the radio hardware. The Embedded Series is not intended to be used with a host computer but for stand-alone operation applications.

Next few months I will be working with a couple of USRP N210 kits, this hardware has a Spartan 3A-DSP 3400 FPGA as its main feature. It also has dual 14-bit ADC (analog-to-digital converter) with a capacity of 100 MS/s (mega-samples per second) and 400 MS/s 16-bit DAC (digital-to-analog converter). The next figure shows the basic architecture of the USRP N210.

USRP N210 Architecture. Source.

It is very interesting to compare the architecture of this hardware (and any other hardware of its kind) to a basic SDR reference architecture as the one shown in the next figure.

Ideal SDR architecture. Kenington, P. B. (2005). RF and baseband techniques for software defined

radio (p. 177). Norwood: Artech House.

In a future entry, I will write about how to connect and use USRP with GNU Radio for a complete radio solution.