<title>Novel optical techniques for phased-array processing</title>

From 29 October 2012 to 7 November 2012, 73 supersonic passes of an F-18 aircraft were observed over a dry lake bed at Edwards Air Force Base as part of NASA’s Farfield Investigation of No-boom Thresholds project, which was conceived to measure the characteristics of sonic booms at the boundaries of their decay, where overpressure is exceptionally low, thereby stretching the limits of current prediction methods. Each pass was recorded by a 55-microphone phased array sensor system with a circular aperture diameter of 2000 ft (609.6 m). The data were processed using a novel time domain array processing algorithm to estimate the direction of arrival and trace speed of the sonic boom wave front along the plane of the phased array. The results from the phased array processing are consistent with the known location of the test aircraft for each processed flight and are consistent with expectations for direction of arrival due to atmospheric refraction. Near real-time estimation of the sonic boom direction of arrival, trace speed along the ground, and visualization of the propagation of the sonic boom wave front are possible. This could allow the test team to assess the data and determine if the target of the test point has been met while the test aircraft is still in flight. This would enable improved test efficiency and efficacy, ultimately improving the value of the test campaign. The measured direction of arrival also provides sonic boom propagation numerical prediction code validation. Most sonic boom prediction codes provide the propagation path of the sonic boom and thus the direction of arrival of the sonic boom at a point on the ground. Thus for predictions made using the actual flight data measured at the time of the test, the predicted direction of arrival and measured direction of arrival can be directly compared to help validate the prediction codes.

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2-D Phased Array Processing In Bulk Wave Acoustic Media

10.1117/12.944194 ◽

1988 ◽

Author(s):

R M. Montgomery ◽

J W. Watkins

Keyword(s):

Phased Array ◽

Array Processing ◽

Bulk Wave ◽

Acoustic Media

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Aspects of the Subarrayed Array Processing for the Phased Array Radar

International Journal of Antennas and Propagation ◽

10.1155/2015/797352 ◽

2015 ◽

Vol 2015 ◽

pp. 1-21 ◽

Cited By ~ 1

Author(s):

Hang Hu

Keyword(s):

Phased Array ◽

Array Processing ◽

Direction Finding ◽

Adaptive Beamforming ◽

Fast Time ◽

Configuration Optimization ◽

Numerical Examples ◽

Phased Array Radar ◽

Time Space ◽

Space Time Adaptive Processing

This paper gives an overview on the research status, developments, and achievements of subarrayed array processing for the multifunction phased array radar. We address some issues concerning subarrayed adaptive beamforming, subarrayed fast-time space-time adaptive processing, subarray-based sidelobe reduction of sum and difference beam, subarrayed adapted monopulse, subarrayed superresolution direction finding, subarray configuration optimization in ECCM (electronic counter-countermeasure), and subarrayed array processing for MIMO-PAR. In this review, several viewpoints relevant to subarrayed array processing are pointed out and the achieved results are demonstrated by numerical examples.

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