An antenna structure for telecommunications, in particular by satellite, the antenna structure comprising: - at least one elementary antenna having a helical shape and dimensioned so as to transmit and/or receive at least one electromagnetic wave having a frequency higher than 4 GHz, preferably between 4 GHz and 50 GHz, in particular comprised within a spectral band selected from among the X band and the Ku band, each elementary antenna being devoid of an insertion loop for inserting the magnetic field and further including an insertion element for inserting the electric field, the insertion element being a metal rod and each elementary antenna including, in addition, a dielectric insulation device inserted between the rod and the housing, - a transmitting-receiving surface, with each elementary antenna extending between a first near end that is adjacent to the transmitting-receiving surface and a second distal end that is at a distance from the transmitting-receiving surface, - a housing the base surface of which is the transmitting-receiving surface which delimits an electromagnetic wave feed cavity for feeding electromagnetic waves to the elementary antennas, arranged to be in contact with the transmitting-receiving surface, the dielectric insulation device being inserted between the rod and the housing, characterized in that the antenna structure comprises: - a radome capable of being attached to the housing and comprising a positioning cavity that is able to receive the dielectric device in an inserted position, the dielectric device including a cylindrical crown ring having a circular base presenting a diameter, the transmitting-receiving surface comprising a coaxial access port capable of receiving the dielectric device, with the coaxial access port being cylindrical with a circular base and presenting a first diameter, the first diameter being greater than the diameter of the crown ring. - at least one elementary antenna having a helical shape and dimensioned so as to transmit and/or receive at least one electromagnetic wave having a frequency higher than 4 GHz, preferably between 4 GHz and 50 GHz, in particular comprised within a spectral band selected from among the X band and the Ku band, each elementary antenna being devoid of an insertion loop for inserting the magnetic field and further including an insertion element for inserting the electric field, the insertion element being a metal rod and each elementary antenna including, in addition, a dielectric insulation device inserted between the rod and the housing, - a transmitting-receiving surface, with each elementary antenna extending between a first near end that is adjacent to the transmitting-receiving surface and a second distal end that is at a distance from the transmitting-receiving surface, - a housing the base surface of which is the transmitting-receiving surface which delimits an electromagnetic wave feed cavity for feeding electromagnetic waves to the elementary antennas, arranged to be in contact with the transmitting-receiving surface, the dielectric insulation device being inserted between the rod and the housing, - a radome capable of being attached to the housing and comprising a positioning cavity that is able to receive the dielectric device in an inserted position,