Direction de recherche : Hassan ABOUSHADY

Recepteur radio-frequence pour la radio cognitive

The heavy use of wireless communications bands has made the notion of Cognitive Radio (CR) attractive. Cognitive radio can be achieved by sensing and detecting available frequency bands before initiating communication. RF bandpass Sigma-Delta modulators have been suggested as potential candidates for highly digitized receivers dedicated to cognitive radio applications.
Nevertheless, the measured Dynamic Range (DR) of state-of-the-art RF bandpass Sigma-Delta ADCs is not sufficient to satisfy the requirements of wireless communication standards.
Furthermore, in order to sweep the spectrum and detect different wireless communication standards, it is necessary to have a bandpass Sigma-Delta ADCs with a tunable center frequency.
In this work we propose an Cognitive Radio RF front-end receiver based on a wide-band LNA and a tunable bandpass Sigma-Delta ADC. The proposed RF front-end can operate from 1.5-to-3GHz and can satisfy the specifications of several wireless communication standards in this band.
The main contribution of this work can be summarized in the following:

1. Efficient Technique for tuning the center frequency of BP Sigma-Delta ADCs
2. Design, implementation and measurement of:
   • An Inductor-Less Wide-Band 0.7-3.0GHz Variable Gain Low Noise Amplifier
   • A 6.8-to-9.0GHz Subsampled Tunable RF BP Sigma-Delta ADC
   • A 1.5-to-3.0GHz RF Front-End Receiver based on a tunable RF BP Sigma-Delta ADC

Publications 2016-2022