Self-Healing Mixed-Signal Baseband Processor for Cognitive Radios
Cognitive radios (CRs) are expected to emerge as a critical component in military and commercial applications. These radios are addressing the fact that spectrum is actually poorly utilized in many bands, in spite of the increasing demand for wireless connectivity. On a conceptual level, cognitive radio networks sense the spectral environment and adapt transmission parameters to dynamically reuse available spectrum. This is not just a hypothetical concept, there is actual evidence that the FCC supports this technology and is currently working on the rules for cognitive radio operation in licensed TV bands. The FCC’s interest also extends to higher frequencies, where the spectrum utilization is even lower. The realization of this vision could open up to 100 GHz of spectrum and a new frontier of opportunities for radio designers and wireless application developers. However, the novelty of this approach requires new mechanisms for using radio frequencies through sharing rather than fixed allocations.
A challenging task in cognitive radios is spectrum sensing, i.e., determining which channels are not occupied. In the presence of shadowing, the system must identify signals that are as much as 20 dB below noise. Moreover, this detection has to take place in a very short amount of time, in order to vacate the frequency band before generating any significant amount of interference. Our project focuses on the implementation of a baseband spectrum sensing processor using energy detection and pilot detection.
- Primary Investigators: Danijela Čabrić, Dejan Marković
- Students: Tsung-Han Yu, Oussama Sekkat, Santiago Rodriguez Parera [until Oct. 2009]
- T.-H. Yu, C.-H. Yang, D. Markovic, D. Čabrić, "An Energy-Efficient VLSI Architecture for Cognitive Radio Wideband Spectrum Sensing", in Proc. IEEE Global Communications Conference, 5-9 Dec. 2011, Houston, TX, USA
- T.-H. Yu, O. Sekkat, S. Rodriguez-Parera, D. Marković, and D. Čabrić, "A Wideband Spectrum-Sensing Processor with Adaptive Detection Threshold and Sensing Time," IEEE Trans. on Circuit & System I (TCAS-I), vol. 58, no. 11, pp. 2765-2775, Nov. 2011.
- T.-H. Yu, C.-H. Yang, D. Čabrić, D. Marković, A 7.4mW 200MS/s Spectrum-Sensing Digital Baseband Processor for Cognitive Radios, in Proc. International Symposium on VLSI Technology and Circuits, 13-17 Jun. 2011, Kyoto, Japan
- T.-H. Yu, S. Rodriguez-Parera, D. Marković, D. Čabrić, Cognitive Radio Wideband Spectrum Sensing Using Multitap Windowing and Power Detection with Threshold Adaptation, in Proc. IEEE International Conference on Communications (IEEE ICC), 23-27 May 2010, Cape Town, South Africa