Beamforming sonar systems for side live sonar, and associated methods

A marine electronic device for generating and presenting sonar imagery of an underwater environment relative to a watercraft, the marine electronic device comprising:

• a display;
• a processor;
• and
• a memory including computer executable instructions, the computer executable instructions configured to, when executed by the processor, cause the processor to:
• receive first sonar return data at substantially a same time from one or more first sonar transducer arrays, wherein the one or more first sonar transducer arrays are positioned and aimed outwardly and downwardly from a first side of the watercraft, and wherein each of the one or more first sonar transducer arrays comprises a plurality of first transducer elements, wherein at least one of the one or more first sonar transducer arrays are oriented with a longitudinal axis defining a first angle within a mounting plane dimension relative to a vertical centerline plane of the watercraft, wherein the mounting plane dimension is parallel to a waterline of the underwater environment, wherein the first angle is between 10°-40° from the vertical centerline plane;
• receive second sonar return data at substantially the same time from one or more second sonar transducer arrays, wherein the one or more second sonar transducer arrays are positioned and aimed outwardly and downwardly from a second side of the watercraft, wherein each of the one or more second sonar transducer arrays comprises a plurality of second transducer elements, and wherein the second side of the watercraft is opposite the first side of the watercraft, wherein at least one of the one or more second sonar transducer arrays are oriented with a longitudinal axis defining a second angle within the mounting plane dimension relative to the vertical centerline plane of the watercraft, wherein the second angle is between 10°-40° from the vertical centerline plane;
• filter the first sonar return data based on frequency to form multiple first sonar return beams corresponding to different horizontal angles within a range of angles extending from the first side of the watercraft from a fore-to-aft direction of the watercraft, wherein each of the multiple first sonar return beams is formed using frequency steered beamforming and correspond to substantially the same time;
• filter the second sonar return data based on frequency to form multiple second sonar return beams corresponding to different horizontal angles within a range of angles extending from the second side of the watercraft from the fore-to-aft direction of the watercraft, wherein each of the multiple second sonar return beams is formed using frequency steered beamforming and correspond to substantially the same time;
• generate a first sonar image of the underwater environment that is off to the first side of the watercraft, wherein the first sonar image is a two-dimensional live sonar image that is formed of the first sonar return data from the multiple first sonar return beams from the one or more first sonar transducer arrays, and wherein the first sonar return data used to form the two-dimensional live sonar image was received at substantially the same time by the plurality of first transducer elements;
• generate a second sonar image of the underwater environment that is off to the second side of the watercraft, wherein the second sonar image is a two-dimensional live sonar image that is formed of second sonar return data from the multiple second sonar return beams from the one or more second sonar transducer arrays, and wherein the second sonar return data used to form the two-dimensional live sonar image was received at substantially the same time by the plurality of second transducer elements;
• generate a third sonar image of the underwater environment that is a current and historical view of the underwater environment off to both the first side and the second side of the watercraft, wherein the third sonar image is formed of a first current image slice of sonar image data corresponding to a first subset of the multiple first sonar return beams and a second current image slice of sonar image data corresponding to a second subset of the multiple second sonar return beams, wherein the first subset is at least one of multiple first sonar return beams and less than or equal to ten of the multiple first sonar return beams, wherein the second subset is at least one of multiple second sonar return beams and less than or equal to ten of the multiple second sonar return beams, wherein the first current image slice is positioned at a top of the third sonar image on a right side of the third sonar image, wherein the second current image slice is positioned at the top of the third sonar image on a left side of the third sonar image, and wherein the remainder of the third sonar image is formed of historical slices of sonar image data from prior captured sonar return data from the one or more first sonar transducer arrays and the one or more second sonar transducer arrays;
• and
• cause presentation of the first sonar image and the second sonar image on the display, wherein the first sonar image is presented on the display to the right of the second sonar image from a viewer's perspective, or cause presentation of the third sonar image on the display.

A method for generating and presenting sonar imagery of an underwater environment relative to a watercraft, the method comprising:

• receiving first sonar return data at substantially a same time from one or more first sonar transducer arrays, wherein the one or more first sonar transducer arrays are positioned and aimed outwardly and downwardly from a first side of a watercraft, and wherein each of the one or more first sonar transducer arrays comprises a plurality of first transducer elements, wherein at least one of the one or more first sonar transducer arrays are oriented with a longitudinal axis defining a first angle within a mounting plane dimension relative to a vertical centerline plane of the watercraft, wherein the mounting plane dimension is parallel to a waterline of the underwater environment, wherein the first angle is between 10°-40° from the vertical centerline plane;
• receiving second sonar return data at substantially the same time from one or more second sonar transducer arrays, wherein the one or more second sonar transducer arrays are positioned and aimed outwardly and downwardly from a second side of the watercraft, wherein each of the one or more second sonar transducer arrays comprises a plurality of second transducer elements, and wherein the second side of the watercraft is opposite the first side of the watercraft, wherein at least one of the one or more second sonar transducer arrays are oriented with a longitudinal axis defining a second angle within the mounting plane dimension relative to the vertical centerline plane of the watercraft, wherein the second angle is between 10°-40° from the vertical centerline plane;
• filtering the first sonar return data based on frequency to form multiple first sonar return beams corresponding to different horizontal angles within a range of angles extending from the first side of the watercraft from a fore-to-aft direction of the watercraft, wherein each of the multiple first sonar return beams is formed using frequency steered beamforming and correspond to substantially the same time;
• filtering the second sonar return data based on frequency to form multiple second sonar return beams corresponding to different horizontal angles within a range of angles extending from the second side of the watercraft from the fore-to-aft direction of the watercraft, wherein each of the multiple second sonar return beams is formed using frequency steered beamforming and correspond to substantially the same time;
• generating a first sonar image of the underwater environment that is off to the first side of the watercraft, wherein the first sonar image is a two-dimensional live sonar image that is formed of the first sonar return data from the multiple first sonar return beams from the one or more first sonar transducer arrays, and wherein the first sonar return data used to form the two-dimensional live sonar image was received at substantially the same time by the plurality of first transducer elements;
• generating a second sonar image of the underwater environment that is off to the second side of the watercraft, wherein the second sonar image is a two-dimensional live sonar image that is formed of second sonar return data from the multiple second sonar return beams from the one or more second sonar transducer arrays, and wherein the second sonar return data used to form the two-dimensional live sonar image was received at substantially the same time by the plurality of second transducer elements;
• generate a third sonar image of the underwater environment that is a current and historical view of the underwater environment off to both the first side and the second side of the watercraft, wherein the third sonar image is formed of a first current image slice of sonar image data corresponding to a first subset of the multiple first sonar return beams and a second current image slice of sonar image data corresponding to a second subset of the multiple second sonar return beams, wherein the first subset is at least one of multiple first sonar return beams and less than or equal to ten of the multiple first sonar return beams, wherein the second subset is at least one of multiple second sonar return beams and less than or equal to ten of the multiple second sonar return beams, wherein the first current image slice is positioned at a top of the third sonar image on a right side of the third sonar image, wherein the second current image slice is positioned at the top of the third sonar image on a left side of the third sonar image, and wherein the remainder of the third sonar image is formed of historical slices of sonar image data from prior captured sonar return data from the one or more first sonar transducer arrays and the one or more second sonar transducer arrays;
• and
• causing presentation of the first sonar image and the second sonar image on a display, wherein the first sonar image is presented on the display to the right of the second sonar image from a viewer's perspective, or causing presentation of the third sonar image on the display.

A system for generating and presenting sonar imagery of an underwater environment, the system comprising:

• a sonar transducer assembly mountable to a watercraft, the sonar transducer assembly comprising:
• one or more first sonar transducer arrays positioned and aimed outwardly and downwardly from a first side of the watercraft, wherein each of the one or more first sonar transducer arrays comprises a plurality of first transducer elements;
• and
• one or more second sonar transducer arrays positioned and aimed outwardly and downwardly from a second side of the watercraft, wherein each of the one or more second sonar transducer arrays comprises a plurality of second transducer elements, wherein the second side of the watercraft is opposite the first side of the watercraft;
• a display;
• a processor;
• and
• a memory including computer executable instructions, the computer executable instructions configured to, when executed by the processor, cause the processor to:
• receive first sonar return data from the one or more first sonar transducer arrays;
• receive second sonar return data from the one or more second sonar transducer arrays;
• filter the first sonar return data based on frequency to form multiple first sonar return beams corresponding to the first side of the watercraft;
• filter the second sonar return data based on frequency to form multiple second sonar return beams corresponding to the second side of the watercraft;
• generate a first sonar image of the underwater environment that is off to the first side of the watercraft, wherein the first sonar image is a first two-dimensional live sonar image that is formed of the first sonar return data from the multiple first sonar return beams from the one or more first sonar transducer arrays, and wherein the first sonar return data used to form the first two-dimensional live sonar image was received at substantially a same time by the plurality of first transducer elements;
• generate a second sonar image of the underwater environment that is off to the second side of the watercraft, wherein the second sonar image is a second two-dimensional live sonar image that is formed of second sonar return data from the multiple second sonar return beams from the one or more second sonar transducer arrays, and wherein the second sonar return data used to form the second two-dimensional live sonar image was received at substantially a same time by the plurality of second transducer elements;
• generate a third sonar image of the underwater environment that is a current and historical view of the underwater environment off to both the first side and the second side of the watercraft, wherein the third sonar image is formed of a first current image slice of sonar image data corresponding to a first subset of the multiple first sonar return beams and a second current image slice of sonar image data corresponding to a second subset of the multiple second sonar return beams, wherein the first subset is at least one of multiple first sonar return beams and less than or equal to ten of the multiple first sonar return beams, wherein the second subset is at least one of multiple second sonar return beams and less than or equal to ten of the multiple second sonar return beams, wherein the first current image slice is positioned at a top of the third sonar image on a right side of the third sonar image, wherein the second current image slice is positioned at the top of the third sonar image on a left side of the third sonar image, and wherein the remainder of the third sonar image is formed of historical slices of sonar image data from prior captured sonar return data from the one or more first sonar transducer arrays and the one or more second sonar transducer arrays;
• and
• cause presentation of the first sonar image, the second sonar image, and the third sonar image on the display, wherein the first sonar image is presented on the display to the right of the second sonar image from a viewer's perspective.