|Op. System:||Windows XP/2000/98/Me|
|File size:||714 KB|
Publisher description for Nuclear Locator
The use of phased arrays for finding the bearing angle of electromagnetic and Acoustic sources is well known . Such methods use the Interference pattern created between two or more sensors. The time-delay between sensors of known distance is also employed to provide a calculated difference in the number of waves received between the two sensors from a source . One of the limitations inherent in these methods is the reliance upon a single or small range of sampling frequencies which requires the sensors to be spaced at an integer number of wavelengths apart. This often limits interferometer arrays based on size, for example in ELF or gamma-ray observatories where the wavelengths involved limit the physical construction or performance of the interferometer . The additional requirement to filter at certain frequencies based on a fixed sampling Frequency requires additional computational memory and processing. Interference from outside sources at the same sampling frequency also causes Artifacts and false predictions of the source angle in phased arrays . To alleviate these problems, an energy detection method is proposed that does not require an integer number of wavelengths of a particular sampling frequency for interferometer construction. This method also has the advantage of predicting the Cartesian coordinates of the source relative to the sensors and the intensity of the source. The proposed method uses knowledge of the radiative transfer of energy from the source in conjunction with the spherical pick-up pattern of omnidirectional sensors to perform triangulation. A beamformer can be developed based on the coordinates of the source that improves gain and signal-to-noise ratio in the direction of the source.