1 / 16

Passive Sonar Detection Exercise: USS Seawolf and USS Memphis Analysis

This document outlines a passive sonar detection exercise involving the USS Seawolf attacking the USS Memphis, utilized to enhance sonar detection capabilities. It includes a series of analytical questions focusing on detection indices, thresholds, angles for nulls, directivity index, ambient and total noise levels, transmission loss, signal-to-noise ratio, and overall detectability of the Memphis. By utilizing provided data regarding submarine characteristics, bandwidth, and environmental factors, participants can derive important insights for effective sonar application.

tahlia
Télécharger la présentation

Passive Sonar Detection Exercise: USS Seawolf and USS Memphis Analysis

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. Passive Sonar Wrap Up Exercise And Exam Review

  2. Data • The two submarines described below are to engage in a sonar detection exercise off the coast of Kauai. Use the following data for all questions. • (Note: all numbers are made up and do not reflect reality.) • USS Memphis (Target) • SL of sub 180 dB in band from 100 Hz to 500 Hz • Main tonal in band = 400 Hz due to sound short of 400 Hz generator • USS Seawolf (Attacker) • Use hull array consisting of 50 hydrophones in groups of 4 spaced 30 m down the side of the sub (consider as continuous line array) • Bandwidth of sonar suite = 400 Hz from 100 to 500 Hz • Integration time of sonar suite = 20 ms • Want P(D) = 90%, P(FA) = 0.2% assume ideal sonar processor • NLself = 81 dB in band from 100 Hz to 500 Hz • Environment • Sea State = 1 • Shipping = light • transition range = 14 Kyds

  3. Part 1 • What is the detection index required for detection of the Memphis by the Seawolf? p(D)=90% p(FA)=0.2%

  4. Part 2 • What would be the detection threshold for detecting the Memphis using passive sonar? • Bandwidth of sonar suite = 400 Hz from 100 to 500 Hz • Integration time of sonar suite = 20 ms

  5. Part 3 • What are the angles for the nulls of the Seawolf’s 30 m long hull array (only give from 0 to 90)?

  6. The Angles

  7. Part 4 • What is the Directivity Index for this 30 m long array at the frequency of the principle tonal?

  8. Part 5 • What is the attenuation coefficient at the frequency of the principle tonal? f in kHz

  9. Part 6 • What is the Ambient Noise Level (Sea State and Shipping)?

  10. Ambient Noise Band Levels

  11. Part 7 • What is the Total Noise Level?

  12. Part 8 • If the Memphis were at 16,000 yds from the Seawolf, what would be the Transmission Loss (include attenuation)? transition range = ro = 14 Kyds

  13. Part 9 • If the Memphis were at 16,000 yds from the Seawolf, what would be the signal-to-noise level?

  14. Part 10 • Is Memphis detectable? If so, what is the Signal Excess? >

  15. Part 11 • What is the max detection range of the Memphis by the Seawolf (this time you can ignore attenuation)?

More Related