Borne de Cramér-Rao déterministe pour l'analyse des performances asymptotiques en estimation d'un radar actif

The emergence of digital waveforms in radar and the enthusiasm of the scientific community for their versatility proven in telecom raise the question for radar engineers about improving operational performance by using these new waveforms, particularly in high-resolution scenarios. The results on the subject in open literature are promising, except that they are often based on theoretical models which are a little away from the operational reality or used in simplistic scenarios (e.g. the low number of sources taken into account). Indeed, taking into account a realistic observation model (wideband, high sampling frequency and multisource scenario) leads to estimators whose implementation complexity is not compatible with the computation power available nowadays. An alternative approach is the use of lower bounds on the mean square error of estimators, mainly the deterministic Cram´er-Rao bound. The review of the open literature (including reference books) on the deterministic Cramér-Rao bound reveals lacks in its formulation in the context of radar that interests us, namely MIMO wideband, multisource, multiparameter and multiple observations. Indeed, in the current literature, multiple observations are defined as multiple independent realizations of the same observation model, whereas in radar it is usually a combination of different observation models (waveforms change). This has motivated much of our work, namely the derivation of a general analytical expression for the Cram´er-Rao bound for deterministic MIMO wideband active radar. This work provides a tool for comparing the performance of different highresolution waveforms, including new digital waveforms. In general, the analytical expression of the general Cramér-Rao bound obtained provides the theoretical basis for the development of future high-resolution radar.