摘要:
A method is provided for estimating the polarization ellipticity of an antenna response signal to an incident electromagnetic wave received on a crossed-loop antenna or an Adcock antenna array. The method comprises at least the following steps: measuring the phase offset Δφ between the signals acquired respectively on the cosine and sine path of the antenna; measuring the ratio R between the amplitudes of the signals acquired respectively on the cosine and sine path of the antenna; determining the ellipticity angle τ based on the phase offset Δφ and on the ratio R. The invention applies notably to the discrimination of ionospheric waves from ground and/or sea waves, in particular for a surveillance, eavesdropping, or goniometry system using HF band signals.
摘要:
A method is provided for estimating the polarization ellipticity of an antenna response signal to an incident electromagnetic wave received on a crossed-loop antenna or an Adcock antenna array. The method comprises at least the following steps: measuring the phase offset Δφ between the signals acquired respectively on the cosine and sine path of the antenna; measuring the ratio R between the amplitudes of the signals acquired respectively on the cosine and sine path of the antenna; determining the ellipticity angle τ based on the phase offset Δφ and on the ratio R. The invention applies notably to the discrimination of ionospheric waves from ground and/or sea waves, in particular for a surveillance, eavesdropping, or goniometry system using HF band signals.
摘要:
A system using two magnetic quadrupole antennas, two magnetic dipole antennas and means for processing the respective antenna signal outputs provides unambiguous estimates of elevation and polarization for an incident RF signal. The system uses an efficient procedure to process the signals from a small aperture array of fixed loop elements for the purpose of providing radio direction of arrival information that is free of intrinsic polarization error. The directional information is developed by performing a simultaneous arctangent operation on signals output from the antennas or as the measured phase difference between a quadrature summed quadrupole output and a quadrature summed dipole output compensated by a phase offset between the dipole antennas and the quadrupole antennas.