Abstract: A separation method of multiple signals from their superposition recorded at several sensors is addressed. The method employs polyspectra of the sensor data to extract the unknown signals and estimate the Finite Impulse Response (FIR) coupling systems via a linear equation basic algorithm. The method is useful for multichannel blind deconvolution of colored input signals with (possibly) overlapping spectra. An extension of the main algorithm, which can be applied to non-stationary signals separation such as quasiperiodic signal, is also given. Whats more, the method is applied to electromagnetic radiation measurement. Simulation results verify the effectiveness of the algorithm.