Abstract: The invention relates to an antenna designed to emit and/or receive surface waves with a decametric, hectometric or kilometric central wavelength ?0, characterised in that it comprises at least one horizontal wire aerial element of between 0.5?0 and ?0 in length, and at least three vertical wire aerial elements of the same length between 0.03?0 and 0.1?0, arranged in a same plane and each comprising an upper end and a lower end, said upper ends being connected to the horizontal wire aerial element, said lower ends being designed to be connected to a conducting medium having a substantially horizontal surface. The invention also relates to an antenna, an antenna array and a use of an antenna or of an antenna array.

Abstract: The invention relates to a surface wave antenna system, comprising at least one antenna that is electrically short in the vertical plane, with vertical or elliptic polarization and emitting a radiation, said antenna being linked to a conducting medium exhibiting a substantially horizontal surface. The antenna system being characterized in that it comprises furthermore at least one parasitic wire extending in a direction substantially parallel to the surface of the conducting medium, electrically insulated from each antenna, and arranged in the vicinity of at least one antenna in such a way as to be able to radiate by virtue of the current induced by said radiation of this antenna. The invention makes it possible to combine the resultants of each radiating element in such a way as to control the radiation pattern in the vertical plane.

Abstract: The invention relates to an antenna designed to emit and/or receive surface waves with a decametric, hectometric or kilometric central wavelength ?0, characterised in that it comprises at least one horizontal wire aerial element of between 0.5?0 and ?0 in length, and at least three vertical wire aerial elements of the same length between 0.03?0 and 0.1?0, arranged in a same plane and each comprising an upper end and a lower end, said upper ends being connected to the horizontal wire aerial element, said lower ends being designed to be connected to a conducting medium having a substantially horizontal surface. The invention also relates to an antenna, an antenna array and a use of an antenna or of an antenna array.

Abstract: The invention relates to a surface wave antenna system, comprising at least one antenna that is electrically short in the vertical plane, with vertical or elliptic polarization and emitting a radiation, said antenna being linked to a conducting medium exhibiting a substantially horizontal surface. The antenna system being characterized in that it comprises furthermore at least one parasitic wire extending in a direction substantially parallel to the surface of the conducting medium, electrically insulated from each antenna, and arranged in the vicinity of at least one antenna in such a way as to be able to radiate by virtue of the current induced by said radiation of this antenna. The invention makes it possible to combine the resultants of each radiating element in such a way as to control the radiation pattern in the vertical plane.

Abstract: The antenna comprises a metal excitation loop (B1) to be positioned at a height (h) of at least about 1 above the surface (SM) of a conducting medium (M) and a supply means (A, L1n) to be connected to the conducting medium. The perimeter of the loop is about one half of the operating wavelength, namely ?/2, in length. The loop comprises two approximately parallel portions (I1p-I1n, S1) which are at most about ?/50 apart and are capable of extending approximately parallel to said surface in a plane approximately perpendicular to said surface, currents of opposite direction flowing through said portions. The closest portion to said surface includes an aperture between ends (E1p, E1n) of the loop that are connected to the supply means. The antenna is better protected from space waves and it can be reduced in size by being folded up.

Abstract: To broadcast synchronized radio waves in at least one frequency band in a predetermined territory, antennas (AS, ATI, AE) emit waves to respective coverage areas in which receivers (RQ, RB) measure characteristics of the emitted waves and transmit to a central server (SC) . The server analyzes the characteristics (CO) as a function of prediction models for broadcasting waves in the territory in order to determine adjustment parameters for the antennas. The server transmits the adjustment parameters to the antennas to control them in order to offer a greater diversity of radio broadcasting services and to optimize coverage areas according to different wave propagation modes.

Abstract: To broadcast synchronized radio waves in at least one frequency band in a predetermined territory, antennas (AS, ATI, AE) emit waves to respective coverage areas in which receivers (RQ, RB) measure characteristics of the emitted waves and transmit to a central server (SC) . The server analyzes the characteristics (CO) as a function of prediction models for broadcasting waves in the territory in order to determine adjustment parameters for the antennas. The server transmits the adjustment parameters to the antennas to control them in order to offer a greater diversity of radio broadcasting services and to optimize coverage areas according to different wave propagation modes.