A contained jamming device arranged in a coverage zone in which there can be prohibited radio communication devices, the operation of which it is sought to prevent, characterized in that it comprises at least the following elements: • at least one linear cable comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear cable being linked to one or more effectors via a connector, • said effector element or elements, being adapted for injecting, at at least one end of the linear cable, one or more jamming signals, the power flux P j,f of the jamming signal J j,f in the band B j,f of a carrier f is chosen such that the ratio P S,j/ P J,f between the power flux P S,j,f of the signal S j,f potentially usable by the prohibited device on the carrier f and the power flux P J,f, of the signal J f present on the carrier f to prevent the prohibited device from operating is below the operating threshold Seuil S,j,f of the prohibited device (P S,j/ P J,f ≤ Seuil S,j,f) and in that • the effector or effectors are adapted to generate, for a point M(r,l) where a prohibited radio communication device is located, a value of the spectral density N j,f (r,l) of the jamming signal injected into the linear antenna via the connector such that, for the band B i,f of each carrier f, the following applies: 10. log 10 N j, f r, l. B i, f ≥ 10. log 10 P S, j, f − 10. log 10 Seuil S, j, f + C r 0 + P '. l − l 0 + 10. log 10 r / r 0 + η in which • r, l are the coordinates of a point M, • l 0 designates a reference linear distance, r 0 designates a reference radial distance to the linear element, • P' designates the rate of the linear losses along the antenna radiating from the distance l 0, • -C(r 0) designates the losses by coupling in the band B J at the reference radial distance r 0, • η represents a safety margin taking account of the additional attenuations of the jamming signal in its propagation from the antenna to the prohibited terminal. • at least one linear cable comprising a plurality of orifices Oi allowing the radiation of jamming signals, the linear cable being linked to one or more effectors via a connector, • said effector element or elements, being adapted for injecting, at at least one end of the linear cable, one or more jamming signals, the power flux P j,f of the jamming signal J j,f in the band B j,f of a carrier f is chosen such that the ratio P S,j/ P J,f between the power flux P S,j,f of the signal S j,f potentially usable by the prohibited device on the carrier f and the power flux P J,f, of the signal J f present on the carrier f to prevent the prohibited device from operating is below the operating threshold Seuil S,j,f of the prohibited device (P S,j/ P J,f ≤ Seuil S,j,f) and in that • the effector or effectors are adapted to generate, for a point M(r,l) where a prohibited radio communication device is located, a value of the spectral density N j,f (r,l) of the jamming signal injected into the linear antenna via the connector such that, for the band B i,f of each carrier f, the following applies: 10. log 10 N j, f r, l. B i, f ≥ 10. log 10 P S, j, f − 10. log 10 Seuil S, j, f + C r 0 + P '. l − l 0 + 10. log 10 r / r 0 + η in which • r, l are the coordinates of a point M, • l 0 designates a reference linear distance, r 0 designates a reference radial distance to the linear element, • P' designates the rate of the linear losses along the antenna radiating from the distance l 0, • -C(r 0) designates the losses by coupling in the band B J at the reference radial distance r 0, • η represents a safety margin taking account of the additional attenuations of the jamming signal in its propagation from the antenna to the prohibited terminal. • r, l are the coordinates of a point M, • l 0 designates a reference linear distance, r 0 designates a reference radial distance to the linear element, • P' designates the rate of the linear losses along the antenna radiating from the distance l 0, • -C(r 0) designates the losses by coupling in the band B J at the reference radial distance r 0, • η represents a safety margin taking account of the additional attenuations of the jamming signal in its propagation from the antenna to the prohibited terminal.