HackRF – RTL-SDR – GNURADIO Setup

Orange Pi – Raspberry Pi

HackRF One is an SDR (Software Defined radio) working in transmission and reception in a wide frequency range. 1MHz to 6GHz. RTL-SDR is the cheapest and most well-known SDR working in reception only. Here we will discuss the connection of these 2 SDRs to an Orange Pi or a Raspberry PI and their operation with the GNU Radio software.

Connection of the HackRF One SDR to an Orange Pi Pc2 or Orange PI One Plus running on ARMBIAN or a Radpberry PI.

HackRF Library

In console mode, update your system:

sudo apt-get update
sudo apt-get upgrade

Install the library for hackrf:

sudo apt-get install hackrf

Connect the hackrf to an USB port and check it:

hackrf_info

If the installation is good, you will get a response “Found HackRF” etc … Sometimes with some USB cables that connect the HackRF, there is no response. Change the cable in this case.

Installation GNU Radio Companion

GNU Radio is a very powerful tool for modelling signal processing chains. GNU Radio Companion is a complementary tool allowing to build radio processing chains graphically without writing a line of code. So far for Debian Buster there is only version 3.7.13 which is considered stable.

sudo apt-get install gnuradio

Installation Osmocom SDR and RTL-SDR Drivers

RTL-SDR and Orange PI One Plus

sudo apt-get update

Installation of the USB library:

sudo apt-get install cmake build-essential libusb-1.0-0-dev

We clone Osmocom in the user’s Downloads folder for example:

cd ~/Downloads

sudo git clone https://github.com/osmocom/rtl-sdr.git

Go to the folder rtl-sdr:  cd rtl-sdr

sudo mkdir build

cd build

sudo cmake ../ -DINSTALL_UDEV_RULES=ON -DDETACH_KERNEL_DRIVER=ON

At this point I sometimes got an error because the pkg-config package was not found. Make:

sudo apt-get install pkg-config

and relaunch the cmake from above.

sudo make
sudo make install
sudo ldconfig

Osmocom source module installation

sudo apt-get install gr-osmosdr

GNU Radio launch

You have to be in graphics mode to be able to use this superb signal processing design tool. Personally, I use my orange-pi or raspberry in remote mode. I connect to them by enabling VNC in setup and using the VNC extension in chrome on my PC. On a terminal in graphics mode type:

gnuradio-companion

A message “RANDR” missing … is not important.

Error Xterm executable is missing

If you have when launching a model in gnuradio companion a message of the type Xterm executable is missing and if you are on Armbian or Raspbian (raspberry) go to the configuration folder.

cd ~/.gnuradio

edit grc.conf

sudo nano grc.conf

and add at the end of the file:

[grc]
xterm_executable = /usr/bin/lxterminal

First of all, check that the terminal is installed on your machine. Otherwise installed it with:

sudo apt install lxterminal

Osmocom module

To enter data from HackRF One or RTL-SDR, use the Osmocom source module in GNU-Radio.

It is not necessary to identify the SDR if only one is connected to the processing board. For the gains, it is necessary to make tests to find the good values according to the model of SDR.

Multi-SDR

In the case of several SDRs connected to the processing card, they must be identified. For a hackrf type in a terminal hackrf_info and retrieve the serial number and put it in the ‘Device Arguments’ box. Ex:

hackrf=000000000000000075b068dc3122a607

For an RTL-SDR, type rtl_eeprom and put the serial number. Ex:

rtl:00000002

The difficulty with RTL-SDRs is that they all carry the serial number 1 when they are manufactured. You can reprogram this number by typing:

rtl_eeprom -s 'numéro de série'

With the rtl_eeprom -h command, we have the corresponding help.

Purchases

The HackRF being developed in Open Source can be bought in China at Aliexpress for a hundred Euros. To use it, the Orange Pi solution is very interesting. We forget the Orange Pi Zero which, following the treatment defined in GNU-RADIO, quickly risks running out of power. We are going to move towards 64-bit 4-core processors like the H5 or the H6. I have successfully tested Orange Pi PC2 H5 and Orange PI One Plus H6 for SSB reception and SSB transmission.

Orange PI PC2

The Orange PI PC2 has the following advantages:

  • several USB2 if you want to connect different SDRs
  • An audio output on headphone jack, useful for an HF receiver
Orane PI One Plus

The Orange PI One Plus has the following advantages:

  • The minimum required to control a Hack RF or a RTL-SDR from the network (USB, Ethernet 1Gb / s)
  • A very low price: less than 30 € with food and transport (Ebay or Aliexpress)

Posts on Remote-SDR v1