التفاصيل البيبلوغرافية
| العنوان: |
Two Cardioid Sensors in Perpendicular Colocation – Their “Spatial Matched Filter" Beam Steering |
| المؤلفون: |
Nnonyelu, Chibuzo J., Dr., 1986, Wong, Kainam Thomas |
| المصدر: |
IEEE Sensors Journal. 24(9):15033-15045 |
| مصطلحات موضوعية: |
acoustic arrays, acoustic beam focusing, acoustic beam steering, acoustic beams, acoustic signal processing, array signal processing, beam steering, beams, directional sensors, focusing, Indexes, Matched filters, Microphones, Sensor arrays, Sensors, sonar arrays, spatial filters, underwater acoustic arrays, underwater acoustic transducers, Vectors |
| الوصف: |
Cardioid microphones/hydrophones have been commonplace in practical acoustics. Indeed, cardioid sensors are widely obtainable in retail as diverse commercial models produced by numerous manufacturers. A cardioid sensor has a highly directional gain pattern of α + (1 - α)cos(γ), where α represents the sensor’s cardioidicity index, and γ denotes the impinging wavefront’s spatial angle incident upon the cardioid sensor’s axis. This paper is the first in the open literature to investigate the “spatial matched filter" beam-pattern obtainable from two such cardioids that lie in perpendicular colocation. Such a bi-axial cardioid pair is worth investigating because (i) their diverse orientation successfully realizes two-dimensional (azimuth-polar) directivity with only two sensors, (ii) their spatial colocation is advantageous for physical compactness and also for the decoupling of the data’s time-and-frequency dimensions from the azimuth-and-elevation directional dimensions to simplify signal-processing computation. This present investigation, however, uncovers that this beam-pattern generally peaks away from the nominal preset “look direction", but algorithmic mitigation is made possible by this paper’s pre-steering formula derived here to judiciously pre-adjust the beamformer’s nominal “look direction". Further action-able insights are provided in this paper for the hardware system engineer to pre-select the sensors’ cardioidicity index α for maximum steerability and freedom from sidelobes. |
| وصف الملف: |
print |
| URL الوصول: |
https://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-50997 |
| قاعدة البيانات: |
SwePub |