A method for performing a distortion free, multi-line, receive focusing beamforming of ultrasound signals, comprising the steps of: - transmitting transmit beams by an array of transducers, comprising a certain number of transducer elements, to a target, the transmit beams having a frequency spectral content centered at a carrier radiofrequency fc; - receiving echo signals, by at least part of the transducer elements of the array of transducers, reflected by the target in response to the transmit beams,; - obtaining received echo signals from each of the said at least part of the transducer elements of the array of transducers; - applying, by a I,Q detector, an active filter to the received echo signals from each transducer element in order to obtain complex received signals having in phase and quadrature components; wherein when the spectral content of the in phase and quadrature signal is not centered at the carrier frequency (fc), a conversion of the in phase and quadrature signals (I, Q) is applied to obtain in phase and quadrature signals at radiofrequency (I,O-Rf); - interpolating, by a I, Q interpolation filter, the obtained in phase and quadrature components at the radiofrequency fc (I, Q-RF) by means of up-sampling; wherein the step of interpolating includes applying a combination of a cascade chain of a plurality of up-sampling interpolators and a depth dependent tracking filter; - applying, by a high-time-resolution delay block, a time delay to each of the interpolated in phase and quadrature (I,Q RF) components at the radiofrequency fc and a decimation, to form delayed in phase and quadrature (I,Q-Rf) signal components at the radiofrequency fc; - summing, in a coherent manner, the delayed in phase and quadrature signal components at the radiofrequency fc (I,Q-Rf) to produce a received beamforming output dynamically focused at the target of the in phase and quadrature signals at the radiofrequency fc (I,Q-Rf); the step of interpolating further includes pre-computing extra samples between the obtained in phase and quadrature (I,Q-RF) components, needed for the high-time resolution delay step, storing said pre-computed extra samples in a memory and using said pre-computed extra samples in each multi-line beamforming. - transmitting transmit beams by an array of transducers, comprising a certain number of transducer elements, to a target, the transmit beams having a frequency spectral content centered at a carrier radiofrequency fc; - receiving echo signals, by at least part of the transducer elements of the array of transducers, reflected by the target in response to the transmit beams,; - obtaining received echo signals from each of the said at least part of the transducer elements of the array of transducers; - applying, by a I,Q detector, an active filter to the received echo signals from each transducer element in order to obtain complex received signals having in phase and quadrature components; wherein when the spectral content of the in phase and quadrature signal is not centered at the carrier frequency (fc), a conversion of the in phase and quadrature signals (I, Q) is applied to obtain in phase and quadrature signals at radiofrequency (I,O-Rf); - interpolating, by a I, Q interpolation filter, the obtained in phase and quadrature components at the radiofrequency fc (I, Q-RF) by means of up-sampling; wherein the step of interpolating includes applying a combination of a cascade chain of a plurality of up-sampling interpolators and a depth dependent tracking filter; - applying, by a high-time-resolution delay block, a time delay to each of the interpolated in phase and quadrature (I,Q RF) components at the radiofrequency fc and a decimation, to form delayed in phase and quadrature (I,Q-Rf) signal components at the radiofrequency fc; - summing, in a coherent manner, the delayed in phase and quadrature signal components at the radiofrequency fc (I,Q-Rf) to produce a received beamforming output dynamically focused at the target of the in phase and quadrature signals at the radiofrequency fc (I,Q-Rf); the step of interpolating further includes pre-computing extra samples between the obtained in phase and quadrature (I,Q-RF) components, needed for the high-time resolution delay step, storing said pre-computed extra samples in a memory and using said pre-computed extra samples in each multi-line beamforming.