Spectral analysis of nonuniformly spaced data using least square method

The current study investigates an unevenly spaced spectrum using a least square method. The well known Lomb periodogram approach has many benefits, yet it cannot resolve positive and negative frequencies. Using a modified scheme, positive and negative frequencies were discerned without losing any of the benefits of a Lomb periodogram. One of the properties of the periodogram approach is the relationship between the coefficients, i.e., the Hilbert transformation pair. By utilizing this property, the processing time was reduced by half.