1. A comparative discrimination spectral detection (CDSD) system for the identification of chemicals with overlapping spectral signatures, comprising: a radiation source configured for delivering radiation to a sample; a radiation collector configured for collecting radiation from the sample; a plurality of beam splitters configured for splitting the radiation collected from the sample into a plurality of radiation beams; a plurality of optical filters configured for filtering the plurality of radiation beams; a plurality of radiation detectors configured for detecting the plurality filtered radiation beams; and a processor configured for: receiving a set of reference spectra related to a set of target chemicals and generating a set of base vectors for the set of target chemicals from the set of reference spectra, wherein the set of base vectors define a geometrical shape in a configuration space; receiving a set of filtered test spectra from the plurality of radiation detectors and generating a set of test vectors in the configuration space from the set of filtered test spectra; assessing a geometrical relationship of the set of test vectors and the geometrical shape defined by the set of base vectors in the configuration space; and based on the assessed geometrical relationship of the set of test vectors and the geometrical shape defined by the set of base vectors in the configuration space, establishing a probability that a given test spectrum of the set of filtered test spectra matches a given reference spectrum of the set of reference spectra; wherein the set of base vectors define a polygon having a volume in the configuration space.