BSc thesis project proposal

Cognitive Radio Using USRP

A cognitive radio (CR) network is a disruptive wireless technology alleviating today's spectrum scarcity problem. The CR network paradigm promises open dynamic spectrum allocation, in which every CR (consisting of a pair of nodes, a transmitter and a receiver) opportunistically gains wireless access to the available spectrum without causing harmful interference to authorized users. The underlying radio technology envisioned for CR networks has a large bandwidth, so that it is capable of switching to multiple frequency bands.

CR networks are still at a conceptual stage, with a lot of remaining technological issues to solve, in the front-end circuit design as well as in the signal processing field. In this project, the focus is on the latter issue where a number of crucial questions are posed. How will the CR network sense the available spectrum? How will the CR network use this information to set up communication links?

In this project, some answers to these questions will be given by making use of two Universal Software Radio Peripheral (USRP) platforms. We have two USRP UHD N210 transceivers, each equipped with SBX RF boards (they span 400-4400 MHz). The radios can be either programmed with C++ and python scripting, or using Matlab/ Simulink. Some of our recent compressive spectrum sensing techniques can be used to detect which frequency bands are occupied and which are not. These compressive sensing approaches allow us to scan a wide frequency band with sampling rates below the Nyquist rate. Furthermore, we can let the two USRPs collaborate to reduce the sampling rates per USRP even further. Artificial interference can be created using WiFi transmitters. Once the spectrum is scanned, the USRPs need to use the available frequency bands to set up a communication link. In this activity, different communication protocols can be tested.


  • Implement compressive spectrum sensing on the USRPs.
  • Implement collaborative compressive spectrum sensing on the USRPs.
  • Assess the performance of (collaborative) compressive spectrum sensing using WiFi interferers.
  • Build a communication link between the USRPs using the available frequency bands.
  • Test different communication protocols.

Contact Geert Leus

Circuits and Systems Group

Department of Microelectronics

Last modified: 2014-08-27