The concept of Software-Defined Radio (SDR) basically describes the desire for shifting most of the communication functionality into software implementations. Programmable hardware devices like Digital Signal Processors (DSPs) or FPGAs run core tasks of the transmission systems, like modulation/demodulation, signal generation and coding. The utilization of reconfigurable hardware provides high flexibility. The same hardware can run a huge variety of transmission standards in different frequency bands with programmable channel configurations. Ideally an analog-to-digital converter directly obtains received signals from the antenna. However, for many applications at very high frequencies, A/D converters are still not available either technologically or at acceptable costs. Therefore many practical SDR devices include an additional radio frequency circuit as a first mixing step.
The Chair of Digital Communications Systems provides SDR devices for both teaching and research purposes, specifically USRP devices (Universal Software Radio Peripheral) by Ettus Research. These devices provide wireless, simultaneous tranmission and reception (full-duplex) at a frequency range of 50 MHz to 2200 MHz. All devices have a built-in Gigabit-Ethernet interface which enables connectivity to an IP network and allows remote control from a PC. Furthermore the digital signal processing can be run either on the internal FPGA or on a PC over the network interface.
the following Thesis where created with the help of our USRP devices
|Author / Editor / Organization||Title||Year||Download / Bibtex|
|1||A. Chaaban , A. Sezgin||The DoF of the K-user Interference Channel with a Cognitive Relay||Proc. of the IEEE International Symposium on Information Theory ISIT, Cambridge, MA, USA||BibTeX|
|1||A. Chaaban , A. Sezgin||Capacity Results for a Primary MAC in the Presence of a Cognitive Radio||Proc. of the IEEE global communications conference GLOBECOM, Houston, Texas||BibTeX|
|2||A. Chaaban , A. Sezgin||Living in symbiosis: On achievable rates of an oblivious interference system and a cognitive system||EUSIPCO 2011, Barcelona, Spain||BibTeX|
|3||A. Chaaban , A. Sezgin , .||Interference Alignment and Neutralization in a Cognitive 3-User MAC-Interference Channel: Degrees of Freedom||IEEE CWIT 2011, BC, Canada||BibTeX|
|4||A. Chaaban , A. Sezgin||Information Theoretical Limits on Cognitive Radio Networks||in print, Scientific Research Publishing|