Memristor Based Planar Tunable RF Circuits

Memristors have been recently proposed as an alternative to incorporate switching along with traditional CMOS circuits. Adaptive impedance and frequency tuning are an essential and challenging aspect in communication system design. To enable both, a matching network based on switchable capacitors with fixed inductors is proposed in this paper where the switching is done by memristive switches. This paper analyzes the operation of memristors as a switch and a matching network based on memristors which adaptively tunes with impedance and frequency. With three capacitor banks of each 0.5 pF resolution and two fixed inductors, matching for antenna impedance ranging from 20 to 200Ohms and for frequencies ranging from 0.9 to 3.2GHz is reported. Thereafter, an adaptive planar band-pass filter is implemented on CMOS technology with two metal layers. This adaptive frequency tunable band-pass filter uses a π network with resonator tanks in both arms that operates at 2.45 GHz. It is tunable from 2.8GHz to 7.625GHz range. This tunability is achieved using tunable spiral inductor based on memristive switches. The proposed filter layout is implemented and simulated in ANSYS Designer. The initialization and the programming circuitry to enable adaptive switching of the memristive devices has to be addressed. Since RF memristive devices are not commercially available, circuit level simulations are done as a proof of concept to validate the expected results

The politics of suspects’ geo-genetic origin in France: The conditions, expression, and effects of problematisation

International audienceRecently, genetics has given rise to changes in how people’s origin is conceived. Forensics has started using some of these changes in the shape of new DNA-based tests aimed at determining suspects’ geographic origin. This article analyses how recent practices in this field have been ‘problematised’ in France, in Foucault’s sense of the term, and gives substantial weight to the country’s historical and republican legacy. First, the launch of these genetic tests is examined, looking at the work of actors who helped create the preconditions for this problematisation but at the same time tried to deconstruct it. The paper goes on to focus on how this problematisation is expressed, questioning the arguments used particularly by its opponents who ground their stance in history, law, and science, while also invoking ethical and political concerns regarding data use. Finally, current state regulations on the matter are outlined, showing how ‘points of problematisation’ have been construed in terms of prohibition. The article concludes by underlining the internal tensions (the ‘knot’) of the problematisation process, showing how it highlights changes in contemporary notions of origin and the types of subjects it produces. More generally, the implications of this study for social science research on origin and on the life sciences are also discussed