Ricerc@Sapienza

In this work a dynamic biasing circuit for current conveyor (CCII) applications is proposed and discussed with circuitry details. This solution, applied for the first time to current-mode circuits, allows to decrease the steady state power consumption of the considered circuit, minimally affecting its performance. The dynamic biasing solution here conceived is able to sense the input signal providing an extra current to the CCII only when an input voltage variation occurs.

We propose a novel class-AB second-generation Current Conveyor (CCII) based on the class-AB Flipped Voltage Follower (FVF) topology, and compare it with a class-A CCII based on the conventional FVF. The AB-FVF is capable of driving larger capacitive loads, showing faster settling. Furthermore, it can drive the Z output with currents larger than the biasing ones, improving power efficiency. A modification of a previously published FVF is also introduced to improve the compensation of the frequency response.

This paper presents the design of a novel low-voltage high-speed D-latch circuit suitable for nanometer CMOS technologies. The proposed topology is compared against the low-voltage triple-tail D-latch and its advantages are demonstrated both by simulations, under different performance/power consumption tradeoffs with a 40-nm CMOS technology, and theoretically, thanks to a simple model of the propagation delay derived for both low-voltage topologies.

The analysis of signals defined over a graph is relevant in many applications, such as social and economic networks, big data or biological networks, and so on. A key tool for analyzing these signals is the so-called graph Fourier transform (GFT). Alternative definitions of GFT have been suggested in the literature, based on the eigen-decomposition of either the graph Laplacian or adjacency matrix.

A double sideband continuous wave (DSCW) radar for the monitoring of artery wall movements has been designed and realized. The radar is based on a transceiver, a coherent demodulator and a bow-tie antenna. A feasibility study suggested the 1-3 GHz band as the most suitable for the proposed application. The DSCW radar has been simulated with the microwave office CAD and has been implemented with discrete components. Responses measured on the realized radar are in good agreement with simulations.

This paper addresses the detection of surface slow moving targets by means of an array passive radar based on low-EIRP satellite illuminators of opportunity. Particularly, the use of the receiving array of K elements is considered to provide increased detection capability for targets with limited radar cross section, together with the capability to estimate the target direction-of-arrival. A full processing scheme is proposed to exploit together both the long integration times and the multiple receiving elements.

This paper demonstrates the feasibility and effectiveness of forward-scatter radar (FSR) target detection based on the signals of opportunity made available by standard radio and TV broadcast transmission stations. This passive FSR (P-FSR) operation is obtained by means of a simple and robust correlation process based on self-mixing. This is shown to be very effective in extracting the characteristic FSR modulation produced by airborne targets, from the signals received from frequency modulated, digital audio broadcasting, and digital video broadcasting transmitters of opportunity.

Microsecond pulsed electric fields (?sPEFs) with amplitude of tens of kV/m are used to permeabilize the plasma membrane whereas nanosecond pulsed electric fields of MV/m also permeabilize cell internal structures, such as the endoplasmic reticulum. In this work, a numerical realistic model of cell and its reticulum has been realized to study the use of ?sPEFs also for the permeabilization of this internal structure

Nano-systems, often used in biomedical applications for the treatment of a broad category of illnesses, represent one of the nanomedicine approaches recently proposed to target specific drugs only in the region where the disease has been developed. Recently the use of this technique has been proposed with electropulsation, hence taking advantage of the enhanced permeabilization of the cell membrane and simultaneously control the release of the encapsulated drug by the nano-system.

Microwave thermal ablation (MTA) procedures are based on the absorption of an electromagnetic field irradiated by a minimally invasive antenna. Several studies have been conducted in the past considering different aspects of the technique. However, some points still need to be investigated, as pointed out in the present contribution.