Abstract: A thunderstorm cell detection and mapping system which includes means for acquiring lightning strike information relating to locations of respective lightning strikes, and means for identifying and locating active thunderstorm cells based on the lightning strike information.

Abstract: A lightning strike detection and mapping system which determines the range and bearing of each valid lightning strike by (1) computing the Fourier Transform, and more preferably the discrete Fourier Transform (DFT) of the X and Y waveforms, classifying the lighting strike based on the DFTs, and estimating the range of the lightning strike based on a type-dependent weighted sum of the DFT coefficients; (2) detecting whether the X or Y waveform is a doublet waveform and classifying the lightning strike based on the detection of a doublet; (3) performing range correction based on type classification and tail activity; and (4) reconstructing clipped waveforms in order to extend the dynamic range of the system.

Abstract: Apparatus for associating target reply signals with target signatures, wherein each reply signal is received from a target transponder within a selectable time period, and further wherein each target signature comprises a first set of parameter values that identify a target position and movement relative to an interrogating aircraft, the apparatus including reply processor means for producing a target report for each reply signal, the target report having a second set of parameter values; and report processing means for: 1) comparing each target report with each target signature to identify which report/signature pairs are potential matches, each comparison between a target report and a target signature being based on comparisons of corresponding parameter values to produce a probability of match for each parameter comparison; and 2) identifying which report/signature matches are best based on comparison of each report/signature potential match with each other potential report/signature potential match includ

Abstract: Apparatus for rejecting multipath reply signals received from a target transponder within a selectable time period, comprising: a top antenna and a bottom antenna to detect reply signals; means for determining an altitude code associated with each reply signal detected by the antennas respectively; means for determining a differential time of arrival (DTA) value for each reply signal detected by the antennas respectively; and processing means for: 1) producing, for each top antenna reply signal, a top antenna target report that includes the altitude code and DTA values; 2) producing for each bottom antenna reply signal, a bottom antenna target report that includes the altitude code and DTA data; and 3) comparing each top antenna report data with corresponding data from each bottom antenna report, and marking out each bottom antenna report that is a multipath reply based on such comparison.

Abstract: Methods and apparatus for detecting and decoding transponder reply signals of the type having a plurality of associated time discrete pulses including two bracket pulses and a number of related data pulses that may have been transmitted at discrete data time intervals between the bracket pulses such that the signal content detected during the data time intervals corresponds to the reply signal data code, comprising receiver means for receiving the reply signals and producing in-phase (I), quadrature (Q) phase and video (V) signals for each received pulse; means for detecting received pulses and storing the I/Q/V signals in a first memory; means for storing in a second memory pointer values that correspond to the temporal location of pulse I/Q/V signals in the first memory; means for identifying, based on time of arrival (TOA) values, pairs of potential bracket pulses wherein each pair marks the beginning and end of a reply code; and processor means for 1) determining an angle of arrival (AOA) value for each d

Abstract: A sampled data lightning strike detection and mapping system receives a signal waveform representative of a lightning strike and other electrical activity and samples the waveform to generate a train of data samples representative thereof. The data samples of the train are processed by a first processor to detect the lightning strike and estimate a location thereof. A predetermined number of data samples of the train are processed by a second processor to generate a plurality of frequency signals representative of a frequency spectrum of the processed data samples. The system includes a display which is driven by the first processor to display an indication of the lightning strike based on the estimated location thereof and further driven by the second processor to display a representation of the frequency spectrum. In a preferred embodiment, the first and second processors are embodied in a common signal processor.