VHDL Design and FPGA Implementation of a High Data Rate Turbo Decoder based on Majority Logic Codes

This paper presents the electronic synthesis, VHDL design and implementation on FPGA of turbo decoders for Difference Set Codes (DSC) decoded by the majority logic (ML). The VHDL design is based on the decoding equations that we have simplified, in order to reduce the complexity and is implemented on parallel process to increase the data rate. A co-simulation using the Dsp-Builder tool on a platform designed on Matlab/Simulink, allows the measurement of the performance in terms of BER (Bit Error Rate) as well as the decoder validation. These decoders can be a good choice for future digital transmission chains. For example, for the Turbo decoder based on the product code DSC (21.11)² with a quantization of 5 bits and for one complete iteration, the results show the possibility of integration of our entire turbo decoder on a single chip, with lower latency at 0.23 microseconds and data rate greater than 500 Mb/s

A New Induction Motor Adaptive Robust Vector Control based on Backstepping

In this paper, a novel approach to nonlinear control of induction machine, recursive on-line estimation of rotor time constant and load torque are developed. The proposed strategy combines Integrated Backstepping and Indirect Field Oriented Controls. The proposed approach is used to design controllers for the rotor flux and speed, estimate the values of rotor time constant and load torque and track their changes on-line. An open loop estimator is used to estimate the rotor flux. Simulation results are presented which demonstrate the effectiveness of the control technique and on-line estimation

Adaptive backstepping control of induction motor powered by photovoltaic generator

This paper is aimed at addressing the design of an effective adaptive nonlinear control of a photovoltaic (PV) water pumping system powering a submersible induction motor and a centrifugal water pump. Four objectives are achieved using an adaptive Backstepping controller. First, it is applied to ensure maximum power point tracking, and uses the latter as a reference in regulation of the rotor speed to convert the maximum electrical power into maximum mechanical power. Second, the adaptive controller is synthesized to control motor rotor flux and restrict the magnetic circuit to its linear interval. Third, it is used to online estimate the rotor time-constant and the load torque disturbance estimation. Finally, this controller is employed to limit the stator currents to protect induction motor windings. Mathematical modelling of the main elements of the system is presented. A sliding mode rotor flux estimator is employed in the output feedback control of the whole system. DC-AC converter is controlled by pulse width modulation. The feasibility, the robustness and the effectiveness of the proposed adaptive nonlinear controller are evaluated through simulations in MATLAB/Simulink environment

A New Design of a Miniature L-slot Microstrip Antenna for RFID Tag

International audienc

Backstepping controller of five-level three-phase inverter

Multilevel converters are becoming increasingly used in many industrial applications due to the many advantages that they offer. The improvements in the output signal quality, lower Total Harmonic Distortion (THD) and many other properties make multilevel converters very attractive for connecting photovoltaic generators to medium voltage grid directly or to be used in a local power supply. In this paper, we focus on the implementation of a three-phase five-level diode clamped inverter and design of a performing nonlinear controller using the Backstepping approach. The control objective is to generate, at the system output, sinusoidal three-phase voltages with amplitude and frequency fixed by the reference signal independently of load variations. The performance study of the multilevel inverter and the designed controller are made by simulations in Matlab/Simulink environment

Analysis and control design of two cascaded boost converter

This work aims to study a cascade of two BOOST converters. First, a non- linear model of the whole controlled system is developed. Then, a robust non-linear controller of currents is synthesized using a backstepping design technique. A formal analysis based on Lyapunov stability and average theory is developed to describe the control currents loops performances. A classical PI controller is used for the voltages loops. The study of the stability of the system will also be discussed. Simulated results are displayed to validate the feasibility and the effectiveness of the proposed strategy

Compact CPW-fed dual-band uniplanar antenna for RFID applications

International audienceThis paper presents a novel dual-band uniplanar monopole antenna fed by Coplanar Waveguide (CPW) line suitable for Radio Frequency Identification (RFID) applications especially designed for RFID readers and it operates at 2.45 GHZ and 5.8 GHZ. This antenna is designed with reasonable gain, low profile and low cost achievement. The proposed antenna benefits from the advantages of the CPW line to simplify the structure of the antenna into a single metallic level, hence making it easier for integration with integrated microwave circuits. The simulation results carried out by ADS from Agilent technologies and CST Microwave Studio electromagnetic solvers, demonstrate that we have good performances in term of return loss, gain, radiation pattern and efficiency for the desired frequency bands. This antenna has a total area of 30×45mm 2 and mounted on an FR4 substrate with constant dielectric permittivity 4.4 and thickness of 1.6mm and loss tangent of 0.025. The simulated return loss less than -10 dB at the lower band is about 200 MHz and for the upper band reaches about 400 MHz, which covers the RFID standards. The gain obtained into simulation of this antenna is 1,9 dB at 2.45GHz and 2,8 dB at 5.8 GHz