A method for detecting signals in a frequency-ambiguous digital receiver by aliasing of the frequency spectra, said receiver comprising at least two reception pathways (1, 2, 3, 4), characterized in that, with a sampling frequency for said signals being specific to each pathway, said method comprises at least the following steps: - determining a frequency-wise search band bounded above by a frequency (F max) which is less than or equal to half the smallest sampling frequency from among the sampling frequencies of said pathways, said search band being contained in one and the same ambiguity rank in relation to the sampling frequencies of said pathways; - determining the sampling frequencies of said pathways (1, 2, 3, 4) in such a way that the aliased frequencies corresponding to said pathways are a monotonic function of the true frequency of said signals in said search band; - digitally filtering said signals in said reception pathways (1, 2, 3, 4) in banks of filters (701, 702, 703, 704) of like central frequency which is a multiple of a quantity 1/T and of like width equal to said quantity 1/T, Fech l and Fech m being respectively the sampling frequency of any pathway of order I and of any pathway of order m from among said pathways (1, 2, 3, 4), Fech l /L = Fech m /M = 1/T, L and M being integer numbers; - in said search band, the frequency aliasing of the signal in the pathway of order I giving a response in the filter of rank i and in a pathway of order m a response in the filter of rank k+i or i-k (72, 73, 74), carrying out a computation of inter-correlation (75, 76, 77) between the signals arising from the filters of rank i of central frequency Fech l /L of the pathway of order I with at least the signals arising from the filters of rank i+k or i-k (72, 73, 74) of the pathway of order m, of central frequency (i+k)Fech m /M or (i-k)Fech m /M; - carrying out the detection of the signals by comparing the power of the signal on output from the inter-correlation computation with respect to a given threshold, the frequency of a detected signal being identified by the knowledge of the ranks of said filters. - determining a frequency-wise search band bounded above by a frequency (F max) which is less than or equal to half the smallest sampling frequency from among the sampling frequencies of said pathways, said search band being contained in one and the same ambiguity rank in relation to the sampling frequencies of said pathways; - determining the sampling frequencies of said pathways (1, 2, 3, 4) in such a way that the aliased frequencies corresponding to said pathways are a monotonic function of the true frequency of said signals in said search band; - digitally filtering said signals in said reception pathways (1, 2, 3, 4) in banks of filters (701, 702, 703, 704) of like central frequency which is a multiple of a quantity 1/T and of like width equal to said quantity 1/T, Fech l and Fech m being respectively the sampling frequency of any pathway of order I and of any pathway of order m from among said pathways (1, 2, 3, 4), Fech l /L = Fech m /M = 1/T, L and M being integer numbers; - in said search band, the frequency aliasing of the signal in the pathway of order I giving a response in the filter of rank i and in a pathway of order m a response in the filter of rank k+i or i-k (72, 73, 74), carrying out a computation of inter-correlation (75, 76, 77) between the signals arising from the filters of rank i of central frequency Fech l /L of the pathway of order I with at least the signals arising from the filters of rank i+k or i-k (72, 73, 74) of the pathway of order m, of central frequency (i+k)Fech m /M or (i-k)Fech m /M; - carrying out the detection of the signals by comparing the power of the signal on output from the inter-correlation computation with respect to a given threshold, the frequency of a detected signal being identified by the knowledge of the ranks of said filters.