Abstract: A two-step process for characterization of peaks in a chromatogram is disclosed. Firstly, data corresponding to each peak or pair of peaks in the chromatogram is identified. A unique filter apparatus locates extrema of the curvature of the chromatographic data and a data file is generated containing characteristics of the extrema. A pattern recognition apparatus analyzes the characteristics of the located extrema and classifies the peak or peak combination represented by the data in the file as one peak or peak combination in a set of resolved peaks and selected combinations of resolved peaks. A portion of the chromatographic data, corresponding to the peak or peak combination identified by the pattern recognition apparatus, is identified. This portion includes the signal for said peak and the signal for the baseline upon which the peak is superimposed.

Abstract: Methods of and apparatus for identifying peaks corresponding to the same chemical component in a series of liquid chromatograms to identify the peaks without foreknowledge of the chromatographic behavior of any component in the sample, or even the number of components in the sample.

Abstract: Chromatographic peaks of varying width are detected and integrated by a method and apparatus that uses only the leading edge of the peak itself to detect the onset of the peak and to select for integration of the peak a filter detector having a time constant which matches the filter characteristics to the signal being monitored.A plurality of filter detectors having different time constants are used for identifying the beginning of a peak. The output of all of the filter detectors is scanned to identify the onset of a peak, and the most appropriate filter detector is selected for integrating the peak.

Abstract: Broadband RF excitation for a Fourier transform spectrometer is obtained by synthesizing the time domain excitation from the desired frequency spectrum of RF excitation. Means are provided to Fourier transform the desired spectral data from the frequency domain into the time domain to obtain a modulation output for modulating an RF carrier signal to generate the desired sideband of RF excitation. In a preferred embodiment, the desired frequency domain data, as tabled in the computer, has a pseudorandom phase shift added to each component for scrambling the phases of the RF excitation. The excited RF resonance signals in the time domain are detected, time-averaged, Fourier transformed to the frequency domain and, in the case of phase scrambling, unscrambled by the pseudorandom phase angle sequence, and displayed.