1 / 9

Advanced NRL Source Array Deployment and Measurement Techniques for Acoustic Mapping

This document outlines the deployment and operation of the NRL Source Array and hydrophone systems on July 8, 2011. The focus is on utilizing the broadband capabilities of the NRL MF acoustic system to spatially, temporally, and spectrally analyze reverberation and clutter. Key components include the 10-transducer vertical line array capable of operating at depths from 20 to 200 meters, maximum speed of 4 knots, and a range of recording strategies for effective acoustic sampling. The document also discusses essential equipment and layout for optimal performance during the deployment.

grazia
Télécharger la présentation

Advanced NRL Source Array Deployment and Measurement Techniques for Acoustic Mapping

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sheave and block Source cable to Winch NRL source array Mid-Deployment Position NRL Source Array (and NRL hydrophone/cable) 8 July 2011

  2. Lots of slack 3'-0" Sheave and Block (flaked) drogue NRL winch deck cable DEPLOY NRL source CTD Winch J-box Capstan NRL HLA receiver HLA Weight (flaked) drogue XF-4 source and cable DEPLOY Pre-Deployment Position NRL Source Array (and NRL hydrophone/cable) 8 July 2011

  3. Measurement Approach ~3 kts Drogue Typical separation: < 35 m NOT TO SCALE Experimentally, exploit the broadband capabilities of the NRL MF acoustic system to map out both reverberation and clutter spatially. temporally, and spectrally • Main acoustical sampling strategies • regional surveys, which produce synoptic “snap-shots” of the reverb/clutter • recording at fixed stations to observe the temporal evolution of the reverb/clutter

  4. NRL MF Source Array (MFA) • 10-transducer vertical line array (VLA) cut for ~3 kHz • Frequency: 1.5-9.5 kHz • Towable at up to 4 kts • Depths 20-200 m • 2 NAS suites (depth, tilt, etc.) • ’Quasi-omni’ azimuthally • 10-% duty cycle • Elements individually • controllable • Shadeable, steerable • 440-V power

  5. NRL MF Line-Array Receiver- 32 elements (w/ desen phone) (cut for 5 kHz; 0.1524-m spacing) - HLA or VLA mode - NAS sensors - No VIMs, so ‘sea-state sensitive’ - Max depths ~150 m or so - 30-kHz typical sample rate - Hand deployed off starboard/port

  6. NRL XF-4 Source • - Towable (up to 4 kts) • Omni • Depths: up to 125 m • 10% duty cycle

  7. CONSTRAINT: Need separation of front of amplifier to be  3 feet from an NRL table Sitting height Sitting height XF-4 Amp Stacked Orange Boxes MFA Amp Source deck cables Front of amplifier Need 2 feet of clearance behind back of amp (where its fans are) Hydrophone wires (NRL array) GPS antenna cable 8 July 2011 NRL Main Lab Equipment/Cabling Layout Option A (preferred)

  8. Geoclutter 03 (R/V Oceanus) NRL Amplifier (back and front)

  9. R/V Oceanus Note starboard overhang which made it tricky to crane the NRL amplifier into the dry lab

More Related