SONAR SYSTEM AND PROCESS
First Claim
Patent Images
1. An active sonar system for detecting object(s) in water comprising:
- a transmitter, with an output connection, that generates a transmit signal and a conjugate of said transmit signal;
a transmit transducer array, connected to said transmitter output connection, and configured to produce an acoustic signal in the water in response to said transmit signal;
at least one hydrophone, with a hydrophone signal output connection, configured to receive said acoustic signal from the water and produce a hydrophone signal;
a heterodyne stage having transmit signal and conjugate transmit signal inputs, connected to said transmitter output connection, and a hydrophone signal input, connected to said hydrophone signal output connection and a difference frequency signal output connection, configured to produce a difference frequency signal in response to the hydrophone signal and said transmit signal and said conjugate of said transmit signal;
a frequency filter having connected to said difference frequency output of said heterodyne stage and having an output connection; and
a display having an input connection connected to said frequency filter output connection and configured to display detection of said object(s) in water.
2 Assignments
0 Petitions
Accused Products
Abstract
A sonar system and method of use capable of discriminating a direct acoustic signal present at 60 dB or more above the acoustic echo signal.
-
Citations
16 Claims
-
1. An active sonar system for detecting object(s) in water comprising:
-
a transmitter, with an output connection, that generates a transmit signal and a conjugate of said transmit signal; a transmit transducer array, connected to said transmitter output connection, and configured to produce an acoustic signal in the water in response to said transmit signal; at least one hydrophone, with a hydrophone signal output connection, configured to receive said acoustic signal from the water and produce a hydrophone signal; a heterodyne stage having transmit signal and conjugate transmit signal inputs, connected to said transmitter output connection, and a hydrophone signal input, connected to said hydrophone signal output connection and a difference frequency signal output connection, configured to produce a difference frequency signal in response to the hydrophone signal and said transmit signal and said conjugate of said transmit signal; a frequency filter having connected to said difference frequency output of said heterodyne stage and having an output connection; and a display having an input connection connected to said frequency filter output connection and configured to display detection of said object(s) in water. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method of detecting objects in the water comprising the steps of:
-
generating and transmitting an transmitted acoustical signal in a desired direction in the water; generating conjugate of said acoustical signal;
receiving reflection signal of said transmitted acoustical signal in water from said object;heterodyning said reflection signal with said transmitted acoustical signal and said conjugate of said transmitted acoustical signal to form difference frequency signal; frequency filtering of said difference frequency signal; and displaying said filtered difference frequency signal whereby object is detected. - View Dependent Claims (11, 12, 13, 14, 15, 16)
-
Specification