Software Defined Radio

GNU Radio is a free software development toolkit that provides runtime signal processing blocks to implement software radios using commodity PC platform. GNU Radio applications are primarily written using the Python programming language, while the supplied, performance-critical signal processing blocks are implemented in C++.


Universal Software Radio Peripheral is a USB based board intended to be a hardware front-end of the GNU Radio software. It comes in two versions: USRP and USRP2. Both version share the same expansion interface for RF daughterboards. Following RF confiurations are currently deployed in Orbit:

  • Basic RX (and Basic TX) - 2 - 200 MHz
  • RFX2400 2.3-2.9 GHz Transceiver, 50+mW output
  • RFX900 800-1000MHz Transceiver, 200+mW output
  • RFX400 400 MHz - 500 MHz Transceiver, 100+mW output
  • XCVR2450 2.4-2.5 GHz and 4.9 to 5.85 GHz Dual-band Transceiver, 100+mW output on 2.4 GHz, 50+mW output on 5GHz

USRP (1)

USB and has 2 RX/TX chains and thus supports up to 2 transciever boards. There are 9 USRPs in the main grid and 2 USRPs in sandbox5 that are each attached to one of the Orbit nodes as shown in the following table:

Node Coordinate Side A Side B
[1,2] FLEX-400 FLEX-2400
[1,19] FLEX-400 FLEX-2400
[20,19] FLEX-400 FLEX-2400
[10,11] FLEX-400 FLEX-2400
[20,2] FLEX-400 RFX-2400
[15,5] FLEX-900 RFX-2400
[15,15] XCVR-2450 RFX-2400
[5,15] FLEX-900 FLEX-2400
[5,5] XCVR-2450 RFX-2400
Sandbox 5
[1,1] Basic TX/RX .
[1,2] Basic TX/RX .


USRP2 is a successor of USRP. It has a single RX/TX interface, faster A/D and D/A, larger/faster FPGA and uses GigE for connection to GNU Radio host. Because of these higher bandwith capabilities, the USRP2 boards are connected to third generation Orbit nodes that are currently off the grid (listed location is just for peripheral itself); USRP2 is in its beta release currently and is supported only on Linux.

Node Coordinate (location) RF Daughter Boards
[18,3] XCVR-2450
[3,18] XCVR-2450
Sandbox 3
[1,1] XCVR-2450
[1,2] XCVR-2450

GNU Radio HowTo

ORBIT GNU Radio Tutorials

Last modified 6 years ago Last modified on Sep 11, 2014, 8:49:16 PM
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