Abstract: Flight data recorder receives from an aircraft a data stream specifying values for flight data parameters while an aircraft is in flight. The flight data recorder stores the values in a crash survivable non-volatile memory unit of the flight data recorder. The flight data recorder determines an occurrence during flight of an exception condition based on an evaluation of at least one exception parameter. Responsive to determining the occurrence of the exception condition, the flight data recorder wirelessly communicates selected aircraft data to a remote location external of the aircraft using a wireless transmitter under the exclusive control of the flight data recorder.

Abstract: Flight data recorder receives from an aircraft a data stream specifying values for flight data parameters while an aircraft is in flight. The flight data recorder stores the values in a crash survivable non-volatile memory unit of the flight data recorder. The flight data recorder determines an occurrence during flight of an exception condition based on an evaluation of at least one exception parameter. Responsive to determining the occurrence of the exception condition, the flight data recorder wirelessly communicates selected aircraft data to a remote location external of the aircraft using a wireless transmitter under the exclusive control of the flight data recorder.

Abstract: A metal detector utilizes digital signal processing and a microprocessor to process buffers of information which is received at a periodic rate. Both high and low gain phase quadrature and in-phase signals are provided via a multiplexer to an analog-to-digital converter from a first receive antenna. A second receive antenna provides phase quadrature and in-phase signals also through the multiplexer to the analog-to-digital converter. The received signals are averaged, decimated and low pass filtered to eliminate noise and reduce the quantity of data which must be processed. A threshold (triggering) processing operation is performed to determine whether a valid target signal is present in the data. If not, no further processing is performed. The in-phase and quadrature components are processed using Fourier transforms to select a frequency band which includes the energy for the target signal. The energy in this frequency band is utilized to determine the identification of the target.

Abstract: A metal detector utilizes digital signal processing and a microprocessor to process buffers of information which is received at a periodic ram. Both high and low gain phase quadrature and in-phase signals are provided via a multiplexer to an analog-to-digital converter from a first receive antenna. A second receive antenna provides phase quadrature and in-phase signals also through the multiplexer to the analog-to-digital converter. The received signals are averaged, decimated and low pass filtered to eliminate noise and reduce the quantity of data which must be processed. A threshold (triggering) processing operation is performed to determine whether a valid target signal is present in the dam. If not, no further processing is performed. The in-phase and quadrature components are processed using Fourier transforms to select a frequency band which includes the energy for the target signal. The energy in this frequency band is utilized to determine the identification of the target.