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The emergence of IoT networks in recent years has been accompanied by an increase in the number of small communicating sensors. If the reduction of the electronic board size is enabled by an ever greater integration of circuit functions, the same cannot be said for antenna functions. In the framework of this thesis, we explore the possibilities offered by plastronics for the plastronics for the realization of compact 3D antennas for IoT sensors. Plastronics consists in transferring an electronic electronic development on a plastic part. When the latter is producedby injection (i.e. moulded), it is referred to as Moulded Interconnected Device (DIM). Among the existing technologies for producing DIMs, Direct Laser Structuring allows the transfer of metal tracks onto different types of thermoplastic materials. This work is based on the design of compact antennas on cylindrical substrates for on a cylindrical substrate for communications at 868 MHz, 2.45 GHz and Ultra Wide Band. The contribution of plastronics to contactless antenna feed solutions is also evaluated. The results obtained confirm the potential of LDS technology for the realisation of this type of antenna., L’émergence des réseaux IoT ces dernières années s’accompagne d’une multiplication des capteurs communicants de petite taille. Si la réduction de l’encombrement des cartes électroniques est rendue possible par une intégration toujours plus importante des fonctions circuits, il n’en est pas de même pour les fonctions antennaires. Dans le cadre de cette thèse, on explore les possibilités offertes par la plastronique pour la réalisation d’antennes compactes 3D pour des capteurs IoT. La plastronique consiste à reporter un développement électronique sur une pièce plastique. Lorsque cette dernière est réalisée par injection (donc moulée), on parle alors de Dispositif Interconnecté Moulé (DIM). Parmi les technologies de réalisation de DIM existantes, la Structuration Laser Directe permet le report de pistes métalliques sur différents types de matériaux thermoplastiques. Ces travaux s’articulent autour de la conception d’antennes compactes sur substrat cylindrique pour descommunications à 868 MHz, 2,45 GHz, Ultra Large Bande. L’apport de la plastronique pour des solutions d’alimentation d’antennes sanscontact est aussi évalué. Les résultats obtenus confirment le potentiel de la technologie LDS pour la réalisation de ce type d’antennes.

International audience; A compact 3-D, circular line matched dipole (CLMD) antenna is presented in this paper. The realization of the antenna is based on Laser Direct Structuring (LDS) plastronic technology, enabling metallization on plastic parts. Cylindrical holder is chosen to carry the dipole, which implies high bending constraints on the antenna. Miniaturization of the radiating element is obtained by an effective use of 3-D space, resulting in a very low profile length dimensions of 0.14 lambda x0.14 lambda x0.05 lambda operating at 868MHz. Specific attention is paid to the input impedance change due to conformation. An equivalent circuit model is proposed to take into account the conformation and design the matching line. Both simulated and measured results demonstrate good performances, with a 30 MHz bandwidth (i.e., a relative bandwidth of 3.5% with S-11 < -10 dB) around the working frequency. The LDS prototype achieves a maximum gain of 1.2 dBi with a quasi-omnidirectional radiation pattern. This compact and conformal design presents a real interest for pervasive highly integrated ISM band IoT sensors.