International audienceIn this paper, a multiconductor modified enhanced transmission line theory is presented. The constitutive equations of this theory are directly derived from Maxwell's equations without the restriction to the transverse electromagnetic mode, while conserving the mathematical formalism of the classical transmission line theory (TLT). However, the per-unit-length (p.u.l.) parameters become complex and frequency dependent but still have an RLCG form. Besides, these new parameters are expressed as a combination of the classical ones and a high-frequency correction. These equations can be easily solved by the existing classical TLT solvers. The results obtained by this theory are in a much better agreement than the classical TLT with those predicted by a full-wave solver or measurements. © 2016 IEEE

This paper presents an improved approach for guaranteed state estimation combining set-membership estimation techniques based on zonotopes and ellipsoids, applied on linear discrete-time systems with unknown but bounded perturbations and noises. The proposed approach starts with a zonotopic approximation and continues with an ellipsoidal approximation; this allows to manage the trade-off between the accuracy of the zonotopic estimation and the reduced complexity of the ellipsoidal estimation. A new criterion based on the P -radius of a zonotope is proposed to make the transition from the zonotopic estimation to the ellipsoidal estimation. An illustrative example is analyzed to show the advantages of the proposed approach.

This paper proposes a new ellipsoid-based guaranteed state estimation approach for linear discrete-time systems with bounded perturbations and bounded measurement noise. This approach is based on the minimization of the radius of the ellipsoidal state estimation set. Firstly, the ellipsoidal state estimation is computed by off-line solving a Linear Matrix Inequality optimization problem. Secondly, a new online method is developed in order to improve the accuracy of the estimation but it leads to an increase of the online computation load. A new scaling technique is proposed to reduce the computation time, while keeping a good accuracy of the state estimation. An illustrative example is analyzed in order to show the advantages of the proposed approach.

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In the context of state estimation of dynamical systems subject to bounded perturbations and measurement noises, this paper proposes an application of a guaranteed ellipsoidal-based set-membership state estimation technique to estimate the linear position of an octorotor used for radar applications. The size of the ellipsoidal set containing the real state is minimized at each sample time taking into account the measurements performed by the drone's sensors. Three case studies highlight the efficiency of the estimation technique in finding guaranteed bounds for the octorotor's linear position. The computed guaranteed bounds in the linear trajectory are exploited to find the maximum operating frequency of the radar, a necessary information in radar applications.

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This paper proposes a new Fault Tolerant Control technique based on the Multiple Models approach for linear systems with bounded perturbations and measurement noises. The consistency of each model with the measurements is checked at each sample time, using an ellipsoidal set-membership state estimation. A Min-Max Model Predictive Control is developed in order to find the optimal control and the best model in spite of the simultaneous presence of component and/or actuator and/or sensor faults. An illustrative example is analyzed in order to show the effectiveness of the proposed approach.

Abstract-This paper introduces a modified enhanced transmissionline theory to account for higher-order modes while using a standard transmission line equation solver or equivalently a Baum, Liu and Tesche (BLT) equation solver. The complex per-unit-length parameters as defined by Nitsch et al. are first cast into an appropriate per-unitlength resistance, inductance, capacitance and conductance (RLCG) form. Besides, these per-unit-length parameters are modified to account for radiation losses with reasonable approximations. This modification is introduced by an additional per-unit-length resistance. The reason and explanations for this parameter are provided. Results obtained with this new formalism are comparable to those obtained using an electromagnetic full-wave solver, thus extending the capability of conventional transmission line solvers.