Interference comprising an intermodulation product of at least a first signal and a second signal is detected in a wireless network, by generating, on the basis of at least the first signal and the second signal, at least one interference signal comprising a simulated intermodulation product and correlating the at least one interference signal with a waveform received in the wireless system to produce data representing a correlation. The presence of an intermodulation product of at least the first signal and the second signal is detected in the interference in dependence on the data representative of the correlation.