A method for making weighted linear combinations of the spectra acquired by a phased-array coil is described. Unlike most previous combination methods, no special reference points in the data are chosen to represent the coil weights. Instead, all the data points are used, which results in optimal signal-to-noise ratio more reliable estimation. The method uses singular value decomposition to identify the coil weights and extract the principal component of variation in the signal. Subsequent processing of the combined signal (e.g., Fourier transform, baseline correction, phasing) may proceed as per a single coil acquisition.