A method for identifying interfering transmitters from among a plurality of known satellite transmitters, wherein a signal is determined for each satellite transmitter present via equidistant sampling of each respective signal strength and a comparison parameter for each satellite transmitter is determined for said signal, the method comprising:
- a) subdividing the signal into a number of succeeding signal periods of predefined equal length;
- b) mapping each sample value via a constant and monotonically increasing or decreasing normalization function to a normalized sample value within a predefined normal interval;
- c) producing a sampling vector having two elements for each normalized sample value, a first element of said sampling vector corresponding to the normalized sample value and a second element of said sampling vector being selected such that a vector noun applied to the sampling vector yields a value of 1;
- d) entering the first and second sampling elements of the sampling vectors into a signal matrix, elements originating from the same signal period each being entered in the same row of the signal matrix;
- e) arranging first and second elements of sampling vectors which were each determined at a specific sampling time instant in relation to sample values determined at a start of a respective signal period in the same column of the signal matrix, separate columns being provided for each of the first and second element;
- f) normalizing elements of the signal matrix such that an application of a predefined vector norm to the signal matrix always yields the value of 1, or g) performing a singular value decomposition of the signal matrix into a product representation in accordance with the following relationship:
- M=USV†,
- where U and V are each unitary matrices;
- and
- h) selecting at least one row of a unitary matrix V† determined for the respective signal as a comparison parameter and assigning the at least one row to the respective signal to prepare the respective signal for the comparison;
- wherein upon detection of an interfering transmitter for the signal emitted by the interfering transmitter, an interference signal is determined in each case via equidistant sampling for each respective signal strength and a comparison parameter is likewise determined for said interference signal, for the determination of the comparison parameter for the respective signal and the comparison parameter for the interference signal, each of which is performed in accordance with steps a) to h);
- and
- wherein the comparison parameter for the interfering transmitter is compared with each of the comparison parameters for the transmitters and, in each case, a dimension value is held available which indicates a degree to which the signal of the interfering transmitter matches the signal of the respective satellite transmitter.