Spectrum sensing applications cover a wide variety, such as efficient utilization of the frequency spectrum in wireless communication or measurement of the Radio-Frequency Electromagnetic-Field (RF-EMF) in medical applications.
A popular technique used for Spectrum sensing is Energy Detection. The current implementations of this technique suffer from several drawbacks. Wide-band spectrum sensing circuits consume a large power and are not suitable for portable devices. Furthermore they suffer from I/Q imbalance. The choice of the detection threshold has a large impact on the Spectrum sensing performance, namely the probability of detection and the probability of false alarm.
In this thesis, we propose a power-efficient highly digitized RF receiver suitable for portable devices.
The proposed circuit does not suffer from I/Q imbalance. The performance of this circuit has been validated by measurement results from a chip fabricated in a 65 nm CMOS technology. A general methodology has been proposed to determine the detection threshold. The proposed method has been validated by simulation and it has been used to study the impact of non-linearity on the spectrum sensing performance. A circuit implementation of a digital backend of the proposed system is presented. This implementation comprises an efficient down-conversion mixer, decimation filter, custom FFT block, and energy detection module. The implementation was validated on FPGA using the on-chip logic analyzer.
In this work, we also present the first hardware measurement of the I/Q imbalance on spectrum sensing performance using a conventional Software Defined Radio receiver.
In the medical field, we also present for the first time a study of the effect of RF-EMF exposure on newborns by performing simultaneous acquisitions of RF-EMF signals and neonates physiological parameters.
Defence : 06/02/2020 - 15h - Visioconférence
Jury members :
Lirida Naviner, Professeur, Télécom Paris, France, [rapporteur]
Khaled Salama, Professeur, King Abdullah University of Science and Technology, KSA, [rapporteur]
Ramon Parra, Professeur, Center for Research and Advanced Studies of the National Polytechnic Inst., Mexico
Mostafa Hussein, Professeur, Arab Academy of Science and Technology, Egypt
Bryce Minger, Ingénieur de recherche, Thales, France
Haralampos Stratigopoulos, Chargé de recherche CNRS HDR, Sorbonne Université, France
Naceur Malouch, Maître de conférences HDR, Sorbonne Université, France
Thi Mai Trang Nguyen, Maître de conférences HDR, Sorbonne Université, France
Hassan Aboushady, Maître de conférences HDR, Sorbonne Université, France
- T. Badran : “Balayage de spectre utilisant des récepteurs RF radio logicielle”, thesis, defence 06/02/2020, supervision Aboushady, Hassan (2020)
- A. Sayed, T. Badran, M.‑M. Louërat, H. Aboushady : “A 1.5-to-3.0GHz Tunable RF Sigma-Delta ADC With a Fixed Set of Coefficients and a Programmable Loop Delay”, IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 67 (9), pp. 1559-1563, (Institute of Electrical and Electronics Engineers) (2020)