Questions tagged [sonar]

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1answer
1k views

How do I implement an adaptive thresholding algorithm for underwater sonar

I want to implement an adaptive thresholding algorithm in MATLAB for filtering data received by an underwater sonar receiver. The data received has an interactive noise component resulting from ...
2
votes
1answer
68 views

How to extract a signal received from a given angle by two microphones

Please bear with me, as I'm only a programmer, and have no knowledge of signal processing as a discipline. I have an application which generates a short pulse of 12 kHz frequency sound from a single ...
1
vote
2answers
184 views

Doppler Shift and the Pulse Repetition Interval

Suppose that I have a signal $x(t)$ consisting of $N$ pulses at a given frequency $\omega_{c}$. I space them $T$ seconds apart, ie the Pulse Repetition Interval (PRI) for the waveform is $T$. Now ...
1
vote
1answer
117 views

Echo detection for localization

I was reading about active sonar and couldn't quite understand how the echos are recognized. My doubt is, when the sound signal is reflected back, it is greatly attenuated and distorted due to many ...
1
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0answers
24 views

What is the best technique for underwater imaging?

I am currently researching what the best method to take underwater images/video is. The papers I have read go into several different methods: Lidar, Synthetic Aperture Sonar (SAS), optical camera plus ...
1
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0answers
155 views

Interpretation of minimum discernible signal (MDS) in sonar equation

I am working on modelling and simulations of synthetic aperture sonar at component/subsystem level. I have started with standard sonar equations for calculating detection ranges for different ...
1
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0answers
249 views

Use of USRP SDR to process sonar?

I have ordered a USRP kit to do radio signal processing in software. Is there a way to use the same device to process sonar data? What would I do upconvert the sonar to 50 MHz?
0
votes
1answer
49 views

Is there any modern information about a 12-hour periodicity in sonar noise?

I have a copy of Principles of underwater sound by Urick, 3rd edition. In the chapter on The noise background of the sea: ambient noise level, on pages 215/216, it says "The analysis of data in ...
0
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0answers
27 views

How can i identify number of return of the ping in the sonar?

I am writing a fake function which is actually doing active pinging (basically SONAR). I am little confuse here about how to identify the number of sonar return i got ? Let's say i am continuously ...
0
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0answers
8 views

Alternatives to MFCCs for Sonar Classification?

Currently I am processing sonar (.wav) files into MFCC features using the librosa library. I use these features as input for sonar classification. Are there any alternatives to MFCCs -- other ...
0
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0answers
22 views

Sonar parameters required for underwater objects shadow formation

I am doing some research on classification of underwater objects using high-frequency sonar. Can anyone kindly guide me what the essential parameters of sonar are resulting in prominent shadow ...
0
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0answers
171 views

How to remove echo/reflected-sound caused by stationary objects when building a ultrasound based radar

I am emitting ultrasound with a speaker and am trying to track moving objects with a microphone array by detecting doppler shifts. I have succeeded to detect movement. However, to detect the direction ...
0
votes
1answer
94 views

Scan shallow water

I need to scan a shower tray with & without the water running to assess the puddling at the drain, then export a point cloud or surface. Sonar & Laser dont seem to be able to deliver, can ...