A pulsed LIDAR system, adapted to determine a value of a Doppler effect frequency shift (ν Doppler) which is undergone by a series of radiation pulses successively emitted by the system towards a target, between portions of the pulses as received after retroreflection or backscattering on the target and said pulses as emitted by the system, and to provide, based on the value determined for the frequency shift, an estimate of a speed component (V T) of the target which is parallel to an optical emission direction of the system, the system comprising: - a transmission path, configured to produce the series of pulses, - a detection path, configured to detect the pulse portions received after retroreflection or backscattering on the target, and to produce heterodyne detection signals which correspond to the pulses of the series, - a spectral analysis module, adapted to carry out a spectral analysis of the heterodyne detection signals, so that the value of the frequency shift (ν Doppler) results from heterodyne detection contributions which correspond to the pulses of the series, and the transmission path being further configured to form each of the pulses as a superposition of a plurality of pulse spectral components which are emitted simultaneously, are spectrally disjoint, and are associated one-to-one with different central wavelength values, and the system being adapted so that the value of the frequency shift (ν Doppler) which is determined by the spectral analysis module results from a plurality of heterodyne detection contributions which respectively correspond to the pulse spectral components of the pulses of the series the system being characterized in that it is further adapted so that the disjoint spectral components of two pulses which are emitted successively are separated by an inter-component spectral gap which varies between said two successive pulses, and so that said inter-component spectral gap varies periodically during the complete series of pulses. the system comprising: - a transmission path, configured to produce the series of pulses, - a detection path, configured to detect the pulse portions received after retroreflection or backscattering on the target, and to produce heterodyne detection signals which correspond to the pulses of the series, - a spectral analysis module, adapted to carry out a spectral analysis of the heterodyne detection signals, so that the value of the frequency shift (ν Doppler) results from heterodyne detection contributions which correspond to the pulses of the series, and - a transmission path, configured to produce the series of pulses, - a detection path, configured to detect the pulse portions received after retroreflection or backscattering on the target, and to produce heterodyne detection signals which correspond to the pulses of the series, - a spectral analysis module, adapted to carry out a spectral analysis of the heterodyne detection signals, so that the value of the frequency shift (ν Doppler) results from heterodyne detection contributions which correspond to the pulses of the series, and the transmission path being further configured to form each of the pulses as a superposition of a plurality of pulse spectral components which are emitted simultaneously, are spectrally disjoint, and are associated one-to-one with different central wavelength values, and the system being adapted so that the value of the frequency shift (ν Doppler) which is determined by the spectral analysis module results from a plurality of heterodyne detection contributions which respectively correspond to the pulse spectral components of the pulses of the series the system being characterized in that it is further adapted so that the disjoint spectral components of two pulses which are emitted successively are separated by an inter-component spectral gap which varies between said two successive pulses, and so that said inter-component spectral gap varies periodically during the complete series of pulses.