A method for detecting targets, implemented by a multifunction radar wherein the radar comprises an antenna subdivided into at least two portions and is configured to transmit at least two types of signals on distinct frequency bands and to perform at least one ground detection or imaging function. During the transmission phases of an antenna portion, the reception of each antenna portion of the radar is cut. The method comprises, for each range gate, a step of reception of signals, a step of estimation of the autocorrelation matrix associated with the interferences the ground returns and from the thermal noise of the radar and a step of target detection using a test of the generalized maximum likelihood. A multifunction radar configured to implement the method for detecting targets is provided.