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: A method for determining a distance to a passive intermodulation source in a device under test, the method comprising transmitting at least two signals with respective different frequencies to the device under test, receiving a complex response signal from the device under test, the complex response signal comprising a passive intermodulation of the at least two signals, generating an autocorrelation matrix using the complex response signal, the autocorrelation matrix representing power information of the complex response signal, decomposing the complex response signal, using the autocorrelation matrix, into a signal component part and a noise component part and determining a distance to the passive intermodulation source in the device under test using the noise and/or signal component part.

Abstract: A method for determining a distance to a passive intermodulation source in a device under test, the method comprising transmitting at least two signals with respective different frequencies to the device under test, receiving a complex response signal from the device under test, the complex response signal comprising a passive intermodulation of the at least two signals, generating an autocorrelation matrix using the complex response signal, the autocorrelation matrix representing power information of the complex response signal, decomposing the complex response signal, using the autocorrelation matrix, into a signal component part and a noise component part and determining a distance to the passive intermodulation source in the device under test using the noise and/or signal component part.

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.