METHOD AND APPARATUS FOR DIGITALLY BASED HIGH SPEED X-RAY SPECTROMETER

摘要

A high speed signal processing system accepts input data from a detector-preamplifier (20) and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a "hardwired" processor implemented in combinatorial digital logic (25), which detects the presence of x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer (28), which refines the filtered amplitude estimates and binds them to produce the desired spectral analysis. The hardwired processor has two parallel processing channels: a slow channel, which filters the data stream with a long time constant triangular filter for good energy resolution; and a fast channel which filters the data stream with a short time constant triangular filter, detects x-ray events, inspects for pileups, and captures peak values from the slow channel for good events.