A module for detecting a disturbance signal ( S P) during initial receiving by a receiver of navigation information from one or several satellites belonging to a global satellite positioning system, the receiver including a plurality of elementary antennas ( A m) able to receive, in a plurality of arrival directions, electromagnetic signals ( RFin m) comprising navigation information, a forming unit able to form a resultant signal from the electromagnetic signals ( RFin m) received by the elementary antennas ( A m) and a processing unit able to process the resultant signal to extract navigation information therefrom; the detection module being integrated into the forming unit and able to receive the electromagnetic signals ( RFin m) coming from each of the elementary antennas ( A m), analyze these signals ( RFin m) and detect a disturbance signal ( S P) when the receiver is started cold in case of detection of a favored arrival direction of some of the electromagnetic signals ( RFin m); the detection module comprising: a plurality of correlators ( C m), each correlator ( C m) being associated with an elementary antenna ( A m) and being able to calculate, over a given time interval, a correlation value ( c mn) between each electromagnetic signal ( RFin m) from the corresponding elementary antenna ( A m) and a reply signal stored in the receiver, the reply signal ( Rep n) being predetermined as a function of the satellite from which the navigation information is expected; the detection module being further configured for determining for a given time interval, an intercorrelation matrix corresponding to the product of a first matrix made up of the correlation values ( c mn) determined for the same time interval from electromagnetic signals ( RFin m) from different elementary antennas ( A m) and different reply signals ( Rep n), and a second matrix ( C H) equal to the first transposed conjugated matrix; and the detection module being characterized in that it is configured for detecting a disturbance signal when the receiver is started cold when the determinant of each intercorrelation matrix from among a plurality of intercorrelation matrices determined for different consecutive time intervals is strictly below a predetermined threshold ( Th). a plurality of correlators ( C m), each correlator ( C m) being associated with an elementary antenna ( A m) and being able to calculate, over a given time interval, a correlation value ( c mn) between each electromagnetic signal ( RFin m) from the corresponding elementary antenna ( A m) and a reply signal stored in the receiver, the reply signal ( Rep n) being predetermined as a function of the satellite from which the navigation information is expected; the detection module being further configured for determining for a given time interval, an intercorrelation matrix corresponding to the product of a first matrix made up of the correlation values ( c mn) determined for the same time interval from electromagnetic signals ( RFin m) from different elementary antennas ( A m) and different reply signals ( Rep n), and a second matrix ( C H) equal to the first transposed conjugated matrix; and the detection module being characterized in that it is configured for detecting a disturbance signal when the receiver is started cold when the determinant of each intercorrelation matrix from among a plurality of intercorrelation matrices determined for different consecutive time intervals is strictly below a predetermined threshold ( Th).