Method for determining a relative speed (v) of a radar target, wherein: (a) an FMCW radar measurement is carried out, in which a ramp-shaped frequency-modulated transmission signal is transmitted, the modulation pattern of which comprises a first sequence of successive ramps, which are offset in time by a time interval (Tr2r), and at least one further sequence of successive ramps, which are offset in time by the same time interval (Tr2r), wherein the sequences (30; 34) are nested within one another in time, wherein, respectively of those ramps in the sequences that have the same ramp index (j) which counts the ramps of the respective sequence, the ramp in the respective further sequence has a time offset, assigned to the sequence, from the ramp in the first sequence, wherein received signals are mixed down to baseband signals (b1; b2), and (b) a two-dimensional spectrum (50; 52) is calculated from the baseband signals (b1; b2), separately for each of the sequences (30; 34), by way of a two-dimensional Fourier transform, wherein there is a ramp-by-ramp transformation in the first dimension and a transformation by the ramp index (j) in the second dimension, characterized in that (c) values for the relative speed (v) of a radar target, which are periodic with a predetermined speed period, are determined on the basis of a position (k, 1) of a peak in at least one two-dimensional spectrum of the baseband signals (b1; b2), (d) a phase relationship between spectral values obtained in each case at the same position (k, 1) in the separately calculated two-dimensional spectra (50; 52) is checked in respect of a correspondence with phase relationships (a(v)) that are expected for a plurality of the determined periodic values of the relative speed (v), and (e) an estimate for the relative speed (v) of the radar target is selected from the determined, periodic values of the relative speed (v) on the basis of the result of the check. (a) an FMCW radar measurement is carried out, in which a ramp-shaped frequency-modulated transmission signal is transmitted, the modulation pattern of which comprises a first sequence of successive ramps, which are offset in time by a time interval (Tr2r), and at least one further sequence of successive ramps, which are offset in time by the same time interval (Tr2r), wherein the sequences (30; 34) are nested within one another in time, wherein, respectively of those ramps in the sequences that have the same ramp index (j) which counts the ramps of the respective sequence, the ramp in the respective further sequence has a time offset, assigned to the sequence, from the ramp in the first sequence, wherein received signals are mixed down to baseband signals (b1; b2), and (b) a two-dimensional spectrum (50; 52) is calculated from the baseband signals (b1; b2), separately for each of the sequences (30; 34), by way of a two-dimensional Fourier transform, wherein there is a ramp-by-ramp transformation in the first dimension and a transformation by the ramp index (j) in the second dimension, characterized in that (c) values for the relative speed (v) of a radar target, which are periodic with a predetermined speed period, are determined on the basis of a position (k, 1) of a peak in at least one two-dimensional spectrum of the baseband signals (b1; b2), (d) a phase relationship between spectral values obtained in each case at the same position (k, 1) in the separately calculated two-dimensional spectra (50; 52) is checked in respect of a correspondence with phase relationships (a(v)) that are expected for a plurality of the determined periodic values of the relative speed (v), and (e) an estimate for the relative speed (v) of the radar target is selected from the determined, periodic values of the relative speed (v) on the basis of the result of the check.