Patent ID: 8674871
Filing Date: 2014-03-18
Classification: G01S

Abstract:
1. A method for aiding environmental characterization using an ultra-wideband multi-node wireless communication network, comprising the emission of impulse radiofrequency signals by a radio emitter node having an emission antenna and the reception of the corresponding signal by a radio receiver node different from the emitter node and having a reception antenna, the method comprising the following steps, carried out by an electronic computer processor: the storage, in a memory associated with the receiver, of a series of descriptors of predicted elementary waveforms, each descriptor corresponding to an elementary waveform expected at the level of the receiver for a determined interaction between the electromagnetic wave emitted by the emission antenna and constituent materials of surfaces potentially present in the environment which may affect the propagation of the wave up to the receiver, the digitization of the signal received and the determination of one or more temporal portions of the waveform of signal received which, because of their temporal distribution of energy, are apt to contain one of the predicted waveforms and to correspond to the arrival of one and the same impulse signal having followed several paths of different orientations between the emitter node and the receiver node, the comparison between on the one hand a descriptor of the signal received for each of these temporal portions and on the other hand several descriptors of predicted waveforms, which descriptors are stored in the memory or calculated on the fly on the basis of the stored descriptors, these descriptors being dependent on an angle of emission and/or of reception, the selection for each temporal portion of one descriptor for which the comparison indicates a resemblance between the predicted form and the temporal portion of form received, the storage of an item of information about each descriptor thus selected and about the position over time of the corresponding temporal portion, representing an item of information regarding presence and position in the environment of a noteworthy object which causes an interaction corresponding to the interaction associated with the selected descriptor, wherein certain descriptors of predicted waveform are each associated with a triple of determined angular parameters, which are a direction of emission, referenced with respect to the emission antenna, and a direction of reception, referenced with respect to the reception antenna, an angle of incidence on a reflecting surface, referenced with respect to the direction normal to the surface, and with an electromagnetic parameter which carries an item of information about the type of material constituting the reflecting surface, the waveform associated with this descriptor being the waveform predicted in the case where the reception antenna receives along said direction of reception an impulse electromagnetic wave emitted by the emission antenna along said direction of emission, after a reflection at this angle of incidence on a surface whose electromagnetic characteristics are represented by said electromagnetic parameter.