1. A method for fighting interference in a communication system where the links are of frequency-hopping type, the signal includes several frequency time slots, the system comprising at least one main sensor and one or more auxiliary sensors, the method comprising the following steps: inserting one or more guard band between the useful bands of the frequency-hopping signal, the total area of the inserted guard bands being chosen so as to satisfy a chosen value of probability of interference interception, an extended time slot being formed of several extended blocks consisting of useful blocks and of the inserted guard bands, selecting the signals of the inserted guard bands whose level is greater than a given threshold, determining a set of spatial-filtering weightings, for each time slot of the signal, by taking account of the correlation matrix of the noise plus jammers alone on the signals selected, and filtering by the set of calculated weightings, the baseband signals of the assemblage of extended blocks of the time slot so as to generate extended blocks devoid of interference.