US 7,920,821 B2 · All ship speeds correlation SONAR simulator

Abstract

The present invention is a system that mathematically simulates acoustic waves that are reflected off an ocean floor from a SONAR transducer mounted on a ship, submarine, or other water navigable craft. By varying the number of mathematical equations, the form of the equations, and the parameters of the equations, many different conditions may be simulated in the laboratory before testing and implementing a SONAR system at sea. The system can simulate either a spatial hydrophone SONAR system or a temporal hydrophone SONAR system for all ship speeds (i.e. all velocity components). The novel equations used in the system are based on the physics of correlation SONAR, and are applied in real time simulation environments to provide for accurate SONAR simulation of a ship's velocity.

Claims11

Dependent claims

A process for testing a SONAR system via simulated acoustic waveforms, wherein the SONAR system comprises an array of hydrophones, and wherein the process comprises:

generating a first correlation function that is representative of a first simulated reflected acoustic waveform and a second simulated reflected acoustic waveform, wherein the first correlation function enables correlation of a relatively earlier-in-time pulse received at a first hydrophone in the array to simulate any desired velocity;
generating an analog signal based on the first correlation function;
providing the analog signal to the SONAR system;
generating an estimate of the desired velocity in the SONAR system based on the analog signal;
and
outputting the estimate of the desired velocity.

3 more elements

A process for testing a SONAR system via simulated acoustic waves, wherein the SONAR system comprises a two-dimensional array of hydrophones having a number, i, of hydrophones in the array, the process comprising:

generating a first correlation function that is representative of simulated reflected acoustic waves, wherein:
(a) the first correlation function enables correlation of a relatively earlier-in-time pulse received at a first hydrophone in the array with a relatively later-in-time pulse received at a second hydrophone in the array to simulate any desired velocity of a vessel;
(b) the first correlation function includes a first term that represents a first simulated acoustic waveform that is oriented in a first direction;
and
(c) the first correlation function includes a second term that represents a second simulated acoustic waveform that is oriented in a second'direction;
and
inputting said first correlation function into a waveform generation system, wherein said waveform generation system produces an analog signal based on the first correlation function;
inputting the analog signal to the SONAR system;
generating an estimate of the desired velocity of the vessel in the SONAR system based on the analog signal;
and
outputting the estimate of the desired velocity.

8 more elements

Dependencies are inferred from the claim text.

All ship speeds correlation SONAR simulator

Life of this patent

All ship speeds correlation SONAR simulator

Life of this patent

Abstract

Claims11