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 (D7), 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 (D1), the first diameter (D1) being greater than the diameter (D7) 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, <EOS>