Data acquisition system comprising a circuit for converting a high-frequency analog input signal (a) into a plurality of digital signals (D.sub.1 -D.sub.N, R) for processing by a digital processing system including at least one digital processor (8) comprising a m-bits digitizer (1), a demultiplexer (2) for delivering in parallel N m-bits sample values supplied in series by said digitizer (1), and a memory (5) for storing the demultiplexed sample values, said memory (5) being accessible by said digital processing system (8). According to the invention, the circuit further comprises a real time digital processing circuit (6) for processing in real time said demultiplexed sample values, capable of supplying processed results to said digital processing system (8). The sampling frequency of said digitizer (1) is greater than the input frequency of said digital processor (8).

The analog-to-digital conversion system comprises an analog-to-digital converter that includes a digital output, memory having a data input and a data output, an output port, an input data bus that extends from the digital output of the analog-to-digital converter to the data input of the memory and an output data bus that extends from the data output of the memory to the output port. The analog-to-digital converter is structured to generate digital samples at a sampling rate. The input data bus is structured to operate at the sampling rate of the ADC. At least one of the data output of the memory, the output data bus and the output port is structured to operate at a maximum rate less than the sampling rate.

A method and apparatus for extending the dynamic range of a data acquisition device. A system of multiple anode detectors are used to increase the dynamic range of a time-to-digital converter. Multiple anodes enable the system to determine characteristics of a signal without distortion of the signal which normally occurs with large signals, or obscuring of the signal by noise which normally occurs with small signals. The data from the multi-anode system can be processed so that the total number of impacts of the signal on the multiple anodes are summed during selectable time frames and made available as multiple bit words. This approach combines virtually all the advantages of a transient digitizer with the advantages of a time to digital converter when acquiring signals from pulse-based detectors such as microchannel plates.

A method and apparatus for compression and filtering of data associated with spectrometry. The method and apparatus serves to recognize peak events and filter data associated with background noise, thereby reducing the volume of data to be transferred to storage and the data transfer rate required for storing the desired data. The method of the present invention monitors the value of each data point as it is encountered and compares it to the previously encountered data to determine whether it is on or very near a peak. The y values for each data point are continuously summed and averaged to determine the average background level. The deviation .delta..sub.i is determined for each subsequent data point and is used to determine a threshold. Each subsequent data point is compared to the threshold and, if found to be above the threshold, is assumed to be part of or very near a peak. At this point, the averaging is stopped until a subsequent data point is determined to be below the threshold. After any peaks have been detected, all or a portion of the data associated the background noise and scatter in the spectrum may be discarded, with only the data relevant to the peaks, and any other desired data kept. Other desired data may include data associated with background noise close to each peak, every n.sup.th data point, the first group of data points encountered, and data corresponding to the first and last groups of data points in each block of data. The sensitivity may be varied to raise the threshold with respect to the average background level and eliminate errant background noise from appearing as a peak.

An improved self-calibrating and self-repairing Data Acquisition System (DAS) for use in inaccessible areas, such as onboard spacecraft, and capable of autonomously performing required system health checks, failure detection. When required, self-repair is implemented utilizing a "spare parts/tool box" system. The available number of spare components primarily depends upon each component's predicted reliability which may be determined using Mean Time Between Failures (MTBF) analysis. Failing or degrading components are electronically removed and disabled to reduce power consumption, before being electronically replaced with spare components.