An apparatus, system, and method are disclosed for broad spectrum chemical detection. The method includes determining a similarity sequencing scheme. The method includes receiving an ambient air sample and concentrating the ambient air sample. The method further includes providing the concentrated sample to a gas chromatography (GC) column, and detecting chemical elution from the GC column in a series of similarity sequenced samples based on the similarity sequencing scheme. The method includes de-convoluting the elution data to derive arrival peaks, and determining a concentration of a chemical in the ambient air based on the series of constant log-time data samples. In one embodiment, the method utilizes a modified Z-transform to de-convolute the elution data.