Sonar imaging system for mounting to watercraft

Abstract

A system for use with a boat to provide underwater sonar images includes a GPS receiver for providing GPS position data, a left side scan sonar transducer for transmitting left side scan sonar pulses and for receiving left side scan sonar return signals, and a right side scan sonar transducer for transmitting right side scan sonar pulses and for receiving right side scan sonar return signals. The system further includes signal processing circuitry for processing the left and right side scan sonar return signals to produce side scan image data and a digital processor for causing a display to display an underwater image based upon the side scan image data, wherein the digital processor associates GPS position and side scan image data.

1 . A sonar transducer assembly comprising:
 a housing; and   left and right side scan sonar transducer elements positioned parallel to one another within the housing, each of the left and right side scan sonar transducer elements having a rectangular cross section with a total length of between about three and about seven inches and a total width of between about 0.125 inches and about 0.50 inches and configured to produce a sonar beam having a narrow horizontal beam width and a wide vertical beam width.   
   
   
       2 . The sonar transducer assembly of  claim 1 , wherein the left and right side scan sonar transducer elements are oriented at a predetermined depression angle. 
   
   
       3 . The sonar transducer assembly of  claim 2 , wherein the predetermined depression angle is at least about 20 degrees. 
   
   
       4 . The sonar transducer assembly of  claim 3 , wherein the predetermined depression angle is between about 20 degrees and about 40 degrees. 
   
   
       5 . The sonar transducer assembly of  claim 4 , wherein the predetermined depression angle is about 30 degrees. 
   
   
       6 . The sonar transducer assembly of  claim 1 , further comprising:
 a down scan sonar transducer element positioned in the housing between the left and right side scan sonar transducer elements.   
   
   
       7 . The sonar transducer assembly of  claim 6 , wherein the down scan sonar transducer element is configured to produce a narrow sonar beam. 
   
   
       8 . The sonar transducer assembly of  claim 6 , further comprising an acoustic shield partially surrounding the down scan sonar transducer element. 
   
   
       9 . The sonar transducer assembly of  claim 1 , further comprising mounting members extending from the housing. 
   
   
       10 . The sonar transducer assembly of  claim 9 , wherein the mounting members have mounting holes. 
   
   
       11 . The sonar transducer assembly of  claim 1 , further comprising:
 means for mounting the sonar transducer assembly to a boat.   
   
   
       12 . The sonar transducer assembly of  claim 1 , wherein the housing includes projections for positioning the left and right side scan sonar transducer elements within the housing. 
   
   
       13 . The sonar transducer assembly of  claim 1 , wherein the left and right side scan sonar transducer elements are coupled to the housing by a bonding material. 
   
   
       14 . The sonar transducer assembly of  claim 1 , wherein the left and right side scan sonar transducer elements are piezoelectric ceramic sonar transducer elements. 
   
   
       15 . The sonar transducer assembly of  claim 14 , wherein the piezoelectric ceramic comprises lead zirconate titanate. 
   
   
       16 . The sonar transducer assembly of  claim 1 , further comprising a pair of acoustic shields, each acoustic shield partially surrounding a respective left and right side scan sonar transducer element. 
   
   
       17 . The sonar transducer assembly of  claim 16 , wherein each acoustic shield surrounds all but one side of the respective left and right side scan sonar transducer element. 
   
   
       18 . The sonar transducer assembly of  claim 1 , wherein the left and right side scan sonar transducer elements are about 4.5 inches long. 
   
   
       19 . The sonar transducer assembly of  claim 1 , wherein the left and right side scan sonar transducer elements are about 0.125 inches wide. 
   
   
       20 . The sonar transducer assembly of  claim 1 , further comprising a cable to couple the left and right side scan sonar transducer elements to an electronic controller. 
   
   
       21 . The sonar transducer assembly of  claim 1 :
 wherein the left and right side scan sonar transducer elements are oriented at a depression angle of about 30 degrees;   wherein the housing includes projections for positioning the left and right side scan sonar transducer elements within the housing;   wherein the left and right side scan sonar transducer elements are coupled to the housing by a bonding material;   wherein the left and right side scan sonar transducer elements are piezoelectric ceramic sonar transducer elements; and   wherein left and right acoustic shields surround all but one side of the respective left and right side scan sonar transducer elements.   
   
   
       22 . A sonar system mounted to a boat, comprising:
 a transducer assembly comprising,
 a housing; and 
 left and right side scan sonar transducer elements positioned parallel to one another within the housing, each of the left and right side scan sonar transducer elements having a rectangular cross section with a total length of between about three and about seven inches and a total width of between about 0.125 inches and about 0.50 inches and configured to produce a sonar beam having a narrow horizontal beam width and a wide vertical beam width; and 
   an electronic controller operatively connected to, and for controlling, the left and right side scan sonar transducer elements.   
   
   
       23 . The sonar system of  claim 22 , wherein the electronic controller is operatively connected to the left and right side scan sonar transducer elements via a cable. 
   
   
       24 . The sonar system of  claim 22 , further comprising a down scan sonar transducer element positioned in the housing between the left and right side scan sonar transducer elements. 
   
   
       25 . The sonar system of  claim 24 , wherein the down scan sonar transducer element is configured to produce a narrow sonar beam. 
   
   
       26 . The sonar system of  claim 22 , wherein the left and right side scan sonar transducer elements are oriented at a depression angle of about 20 degrees and about 40 degrees. 
   
   
       27 . The sonar system of  claim 22 , further comprising a display operatively connected to the electronic controller, and wherein images of underwater articles containing details and shadows thereof are generated by the electronic controller and are displayed on the display. 
   
   
       28 . The sonar system of  claim 22 , wherein the electronic controller includes, for each of the left and right side scan sonar transducer elements, a side scan circuit including a transmitter, a receiver, and a transmit/receive switch. 
   
   
       29 . A sonar transducer assembly comprising:
 a housing;   left and right side scan sonar transducers positioned parallel to one another within the housing, the left side scan sonar transducer facing a left side of the housing for transmitting left side scan sonar beam pulses and receiving sonar returns, the right side scan sonar transducer facing a right side of the housing for transmitting right side scan sonar beam pulses and receiving sonar returns, each of the left and right side scan transducers being rectangular with a total length of between about three and about seven inches and having a total width of between about 0.125 inches and about 0.50 inches.   
   
   
       30 . The sonar transducer assembly of  claim 29 , wherein each of the left and right side scan transducers is oriented within the housing at a depression angle of between about 20 degrees and about 40 degrees. 
   
   
       31 . The sonar transducer assembly of  claim 30 , wherein the depression angle is about 30 degrees. 
   
   
       32 . The sonar transducer assembly of  claim 29  and further comprising:
 a down scan sonar transducer positioned in the housing between the left and right side scan sonar transducers.   
   
   
       33 . The sonar transducer assembly of  claim 29  and further comprising:
 mounting members extending from the housing, the mounting members having mounting holes.   
   
   
       34 . The sonar transducer assembly of  claim 29  and further comprising:
 projections for positioning and supporting the left and right side scan sonar transducers in the housing.   
   
   
       35 . The sonar transducer assembly of  claim 29 , wherein the left and right side scan sonar transducers are coupled to the housing by a bonding material. 
   
   
       36 . The sonar transducer assembly of  claim 29 , wherein the left and right side scan sonar transducers are piezoelectric ceramic transducers. 
   
   
       37 . The sonar transducer assembly of  claim 36 , wherein the piezoelectric ceramic comprises lead zirconate titanate. 
   
   
       38 . The sonar transducer assembly of  claim 29  and further comprising an acoustic shield partially surrounding each of the left and right side scan sonar transducers. 
   
   
       39 . The sonar transducer assembly of  claim 29 , wherein the left and right side scan transducers are about 4.5 inches long. 
   
   
       40 . The sonar transducer assembly of  claim 29 , wherein the left and right side scan transducers are located along left and right sides, respectively, of the housing. 
   
   
       41 . The sonar transducer assembly of  claim 29  and further comprising:
 a cable electrically connected to the left and right side scan sonar transducers and extending from the housing.   
   
   
       42 . The sonar transducer assembly of  claim 29  further comprising:
 a down scan sonar transducer positioned in the housing between the left and right side scan sonar transducers;   mounting members extending from the housing;   a cable electrically connected to the left and right side scan sonar transducers and the down scan sonar transducer, and extending out from the housing;   projections for positioning and supporting the left and right scan sonar transducers in the housing; and   left and right acoustic shields partially surrounding each of the left and right side scan sonar transducers, respectively;   wherein each of the left and right side scan transducers is oriented within the housing at a depression angle of between about 20 degrees and about 40 degrees; and   wherein the left and right side scan sonar transducers are coupled to the housing by a bonding material.