A system for determining an actual interferer transmitting an interfering signal including first frequency portions of the interfering signal in a predetermined frequency band of a useful signal is provided. The system includes a signal evaluator configured to determine for each possible interferer of the plurality of possible interferers coefficient information of the possible interferer based on representation information of the possible interferer and based on processing information, such that the coefficient information of the possible interferer and the representation information of the possible interferer together indicate the preprocessed signal, wherein the processing information and the preprocessed signal together indicate the compressed signal.