A system and method for detection of complex sinusoidal signals. The method can include obtaining a set of complex-valued samples of one or more signals, in the presence of unknown noise, using a plurality of sensors. The presence of κ candidate complex sinusoids can be assumed. Then, κ candidate complex sinusoids in the set of complex-valued samples can be estimated. The method can include comparing a measurement of the energy of the κ estimated candidate complex sinusoids with a threshold value. Based on the comparison, a determination can be made whether to assume a different number of candidate complex sinusoids and repeat the estimation and the comparison steps, or to specify the estimated κ candidate complex sinusoids as detected complex sinusoids. The threshold value can be determined using a penalty value which reduces the probability of overestimating the number of complex sinusoids.