32 citations · 87 across the 11 of their papers we have counts for
11 papers
Interleaving techniques for high-throughput chaotic noise generation in CMOS
Sergio Callegari, Riccardo Rovatti, Gianluca Setti
An interleaving technique is proposed to enhance the throughput of current-mode CMOS discrete time chaotic sources based on the iteration of unidimensional maps. A discussion of th…
A Tailed Tent Map Chaotic Circuit Exploiting SI Memory Elements
Sergio Callegari, Riccardo Rovatti, Gianluca Setti
In the implementation of discrete time chaotic systems, designers have mostly focused on the choice and synthesis of suitable nonlinear blocks, while correct and fast operation can…
Achievement of Preassigned Spectra in the Synthesis of Band-Pass Constant-Envelope Signals by Rapidly Hopping through Discrete Frequencies
Sergio Callegari
Spread-spectrum signals are increasingly adopted in fields including communications, testing of electronic systems, Electro-Magnetic Compatibility (EMC) enhancement, ultrasonic non…
Very Low Cost Entropy Source Based on Chaotic Dynamics Retrofittable on Networked Devices to Prevent RNG Attacks
Mattia Fabbri, Sergio Callegari
Good quality entropy sources are indispensable in most modern cryptographic protocols. Unfortunately, many currently deployed networked devices do not include them and may be vulne…
Coding of Stereo Signals by a Single Digital ΔΣ Modulator
Sergio Callegari
The possibility of using a single digital ΔΣ modulator to simultaneously encode the two channels of a stereo signal is illustrated. From the modulated stream, the two channels can…
From Chirps to Random-FM Excitations in Pulse Compression Ultrasound Systems
Sergio Callegari, Marco Ricci, Salvatore Caporale +6
Pulse compression is often practiced in ultrasound Non Destructive Testing (NDT) systems using chirps. However, chirps are inadequate for setups where multiple probes need to opera…
Sample and Hold Errors in the Implementation of Chaotic Maps
Sergio Callegari, Riccardo Rovatti
Though considerable effort has recently been devoted to hardware realization of chaotic maps, the analysis generally neglects the influence of implementation inaccuracies. Here we…
Noise Weighting in the Design of ΔΣ Modulators (with a Psychoacoustic Coder as an Example)
Sergio Callegari, Federico Bizzarri
A design flow for ΔΣ modulators is illustrated, allowing quantization noise to be shaped according to an arbitrary weighting profile. Being based on FIR NTFs, possibly with high or…
Should ΔΣ Modulators Used in AC Motor Drives be Adapted to the Mechanical Load of the Motor?
Sergio Callegari, Federico Bizzarri
We consider the use of ΔΣ modulators in ac motor drives, focusing on the many additional degrees of freedom that this option offers over Pulse Width Modulation (PWM). Following som…
Output Filter Aware Optimization of the Noise Shaping Properties of ΔΣ Modulators via Semi-Definite Programming
Sergio Callegari, Federico Bizzarri
The Noise Transfer Function (NTF) of ΔΣ modulators is typically designed after the features of the input signal. We suggest that in many applications, and notably those involving D…
A CMOS Tailed Tent Map for the Generation of Uniformly Distributed Chaotic Sequences
Sergio Callegari, Gianluca Setti, Peter J. Langlois
This paper describes the design of a modified tent map characterized by a uniform probability density function. The use of this map is proposed as an alternative to the tent map an…