A method of reconstructing an MRI or ultrasound biomedical image, based on compressed sensing includes exciting a body under examination; acquiring image data from the generated signals, wherein the signals are acquired by pseudo-random undersampling; reconstructing the image using a nonlinear iterative algorithm for minimizing an optimization function containing one or more terms for image data sparsity in one or more predetermined domains with a data fidelity constraint term ensuring fidelity to the acquired image data; wherein two or more sets of image data are acquired from the generated signals, each data set being acquired in a different undersampling scheme and/or a different acquisition mode such as to make expected and unavoidable artifacts incoherent; each of the acquired image data set is multiplied by a correction matrix Δ.