AU2015201220B2 - Downscan imaging sonar - Google Patents

Abstract

A downscan imaging sonar utilizes a linear transducer element to provide improved images of the sea floor and other objects in the water column beneath a vessel. A transducer array may include a plurality of transducer elements and each one of the plurality of transducer elements may include a substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallel to longitudinal length of the transducer elements that is significantly less than a beamwidth of the sonar beam in a direction perpendicular to the longitudinal length of the transducer elements. The plurality of transducer elements may be positioned such that longitudinal lengths of at least two of the plurality of transducer elements are parallel to each other. The plurality of transducer elements may also include at least a first linear transducer element, a second linear transducer element and a third linear transducer element. The first linear transducer element may be positioned within the housing to project sonar pulses from a first side of the housing in a direction substantially perpendicular to a centerline of the housing. The second linear transducer element may be positioned within the housing to lie in a plane with the first linear transducer element and project sonar pulses from a second side of the housing that is substantially opposite of the first side. The third linear transducer element may be positioned within the housing to project sonar pulses in a direction substantially perpendicular to the plane. 2225552v1

Description

DOWNSCAN IMAGING SONAR 2015201220 10 Jan 2017

The present application has been divided out of Australian patent application 2010273842 (AU 2010273842). In the description in this specification, reference may be made to subject matter which is not within the scope of the presently appended claims. 5 That subject matter should be readily identifiable by a person skilled in the art and may assist in putting into practice the invention as defined in the presently appended claims.

FIELD OF THE INVENTION

Embodiments of the present invention relate generally to sonar systems, and 0 more particularly, to providing a downscan imaging sonar using a linear transducer.

BACKGROUND OF THE INVENTION

Sonar has long been used to detect waterborne or underwater objects. For example, sonar devices may be used to determine depth and bottom topography, detect 5 fish or other waterborne contacts, locate wreckage, etc. In this regard, due to the extreme limits to visibility underwater, sonar is typically the most accurate way for individuals to locate objects underwater. Devices such as transducer elements, or simply transducers, have been developed to produce sound or vibrations at a particular frequency that is transmitted into and through the water and also to detect echo returns :0 from the transmitted sound that return to the transducer after reflecting off an object. The transducers can convert electrical energy into sound energy and also convert sound energy (e.g. via detected pressure changes) into an electrical signal, although some transducers may act only as a hydrophone for converting sound energy into an electrical signal without having a transmitting capability. The transducers are often made using :5 piezoelectric materials. A typical transducer produces a beam pattern that emanates as a sound pressure signal from a small source such that the sound energy generates a pressure wave that expands as it moves away from the source. For instance, a circular transducer (e.g., a cylindrical shaped crystal with a circular face) typically creates a conical shaped 30 beam with the apex of the cone being located at the source. Any reflected sound then returns to the transducer to form a return signal that may be interpreted as a surface of an object. Such transducers have often been directed in various directions from surfaced or submerged vessels in order to attempt to locate other vessels and/or the seabed for the purposes of navigation and/or target location. 35 Since the development of sonar, display technology has also been improved in order to enable better interpretation of sonar data. Strip chart recorders and other mechanical output devices have been replaced by, for example, digital displays such as - 1 - 9172742_l.docx 2015201220 10 Mar 2015 LCDs {liquid crystal displays). Current display iephhqiosies continue tofoe improved in grde· to provide, for example, high quality sonar data)pn multi-color, high resolution displays having® more intuitive output than early sonar systems were capable of producing. 5 With: display capabilities advancing to the point at which riphly detailed information tSi abte : tp :be;dSspiay®d, attention |.af| turned Pack to the transducer In order ipi provide higher quality data fpr display. Furthermore, additions! uses have been developed for sonar systems as transducer and display capabilities have evolved. For example, sonar systems have bMhtadtmioped to assist fishermen in; identifying fish and/or the features 10 that tend to attract fish. Hisloncaiiy, these types of sonar systems primarily analysed the column of water beneath a watercraft with a cylindrical piezo element that produces s conicai beam, known as a conieat beam transducer or simply as a circular transducer referring torthe Shape of the face of the cylindrical element However, with the advent of sidescarr sonar fechnoiogy. fishermen were given; the capability to view not oniy toe 15 cdumn of water beoeath their vessel, but also view water to either side of their vessel.

Sidesean sonar can be provided in different ways and with different levels of resolution. As its name implies, sidesean sonar is directed to look to the side of a vessel and not ttelow ihe vessel, in fact, many sidesean sonar systems (e.g., swath and bathymetry sonar systems) have drawn public attention tor their performanceIn the 20 location of famous shipwrecks and for providing verydetailed images of the ocean floor, but such Systems are costly and complex. Sidesean sonar typically generates a somewhat planar fan-shaped beam pattern that is relatively narrow in beamwidfh in a direction parallel to the keel of a;vessel deploying the;Sldescan;Sonar and is relatively Wide In beamwidth in a direeiionpetoendicular to the kepi of the vessel, it may be 25 provided in some cases using multibeam sonar systems. Such multibeam sonar systems are typically comprised of a plurality of relatively narrowly focused cbhstohtiOhafarcular transducer elements that are arrayed next to each Other1 to predyedan array iof narrowly focused adjacent conical i^ams that/together provide a continuous toneHapedbeam pattern. FIG. 1 shows an example of a series of conventional {generally circular) BO transducer elements IQ arrsyedln an arc toproddee a multi be am sonar system. FIG. 2 shows a typical fan shaped beam pattern l2ptoduoed by the multibeam sonar system of FIG. 1 as the beam pattern idprgjeoted ontofhe seabed.

However, muitibeam: sonar systems typically require very complex: systems to supportjhe piursiitybf itohsdu:cers::fb:8t aretorripjoyed in order to torta the muitibeam; 35 sonarisystorhi: For example,.adypicaf system diagram is shown ttri'. a dispiay 20 driven byiO sonar slgpai;processor 22- The sonar signal processor 22 processes signals received ftom each of a plurality of transducers 26 that are fed to the sonar signal processor 22 by respective different transceivers 24 that are paired with each of the transducers 26. Thus conventional multibeam sonar systems tend to include a large number of transceivers and correspondingly introduce complexity in relation to processing the data such systems produce. 2015201220 10 Jan 2017 5 More recently, ceramic sidescan transducer elements have been developed that enable the production of a fan shaped sonar beam directed to one side of a vessel. Accordingly, the sea floor on both sides of the vessel can be covered with two elements facing on opposite sides of the vessel. These types of sidescan transducer elements are linear, rather than cylindrical, and provide a somewhat planar fan-shaped beam pattern 0 using a single transducer to provide sidescan sonar images without utilizing the multibeam array described above. However, employment of these types of sidescan elements typically leaves the column of water beneath the vessel either un-monitored, or monitored using conical beam or circular transducers. In this regard, FIG. 4 illustrates an example of a conventional sidescan sonar with linear sidescan transducer elements 5 oriented to produce fan-shaped beams 27 directed from opposite sides of the vessel and a conical beam 28 projecting directly below the vessel. These conical beams have conventionally been provided using conventional cylindrical transducers to produce depth information since sidescan transducers are typically not as useful for providing depth or water column feature information, such as fish targets. However, cylindrical transducers :0 provide poor quality images for sonar data relating to the structure on the bottom or in the water column directly below the vessel.

Accordingly, it may be desirable to develop a sonar system that is capable of providing an improved downscan imaging sonar.

Alternatively or additionally, it may be desirable to at least provide the public :5 with a useful choice.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a sonar transducer assembly, comprising: a plurality of transducer elements, each one of the plurality of transducer elements having a 30 substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallel to a longitudinal length of the transducer element that is significantly less than a beamwidth of the sonar beam in a direction perpendicular to the longitudinal length of the transducer element, wherein the plurality of transducer elements are positioned such that the longitudinal lengths of at least two of the plurality 35 of transducer elements are substantially parallel to each other, and wherein the plurality of transducer elements include at least: a first linear transducer element positioned within a housing to project sonar pulses from a first side of the housing in a direction substantially perpendicular to a centerline of the housing, a second linear transducer - 3 - 9172742_l.docx element positioned within the housing to lie substantially in a plane with the first linear transducer element and project sonar pulses from a second side of the housing that is generally opposite of the first side, and a third linear transducer element positioned within the housing to project sonar pulses in a direction substantially perpendicular to 5 the plane. 2015201220 10 Jan 2017

The present invention further provides a sonar system comprising: a transducer assembly including a plurality of transducer elements each having a substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallel to a longitudinal length of the transducer element that is significantly less than a 0 beamwidth of the sonar beam in a direction perpendicular to the longitudinal length of the transducer element, wherein the plurality of transducer elements are positioned such that the longitudinal lengths of at least two of the plurality of transducer elements are substantially parallel to each other, and wherein the plurality of transducer elements include at least: a first linear transducer element positioned within a housing to project 5 sonar pulses from a first side of the housing in a direction substantially perpendicular to a centerline of the housing, a second linear transducer element positioned within the housing to lie substantially in a plane with the first linear transducer element and project sonar pulses from a second side of the housing that is substantially opposite of the first side, and a third linear transducer element positioned within the housing to project sonar :0 pulses in a direction substantially perpendicular to the plane; and a sonar module configured to enable operable communication with the transducer assembly, the sonar module including: a sonar signal processor to process sonar return signals received via the transducer assembly, and a transceiver configured to provide communication between the transducer assembly and the sonar signal processor. :5 The present invention still further provides a sonar transducer assembly for imaging an underwater environment beneath a watercraft traveling on a surface of a body of water, the sonar transducer assembly comprising: a housing mountable to the watercraft; a linear downscan transducer element positioned within the housing, the linear downscan transducer element having a substantially rectangular shape configured 30 to produce a fan-shaped sonar beam having a relatively narrow beamwidth in a direction parallel to a longitudinal length of the linear downscan transducer element and a relatively wide beamwidth in a direction perpendicular to the longitudinal length of the transducer element, the linear downscan transducer element being positioned with the longitudinal length thereof extending in a fore-to-aft direction of the housing, wherein 35 the linear downscan transducer element is positioned within the housing to project fanshaped sonar beams in a direction substantially perpendicular to a plane corresponding to the surface of the body of water, said sonar beams being repeatedly emitted so as to sequentially insonify different fan-shaped regions of the underwater environment as the - 3a - 9172742_l.docx watercraft travels; a first linear sidescan transducer element and a second linear sidescan transducer element positioned within the housing, each of the first and second linear sidescan transducer elements having a substantially rectangular shape configured to produce a fan-shaped sonar beam having a relatively narrow beamwidth in a direction 5 parallel to a longitudinal length of the linear downscan transducer element and a 2015201220 10 Jan 2017 relatively wide beamwidth in a direction perpendicular to the longitudinal length of the transducer element, and being oriented in the housing so as to insonify respective fanshaped regions differing from the fan-shaped regions insonified by the linear downscan transducer element. 0 Embodiments of the present disclosure employ a linear transducer, directed downward to receive high quality images relative to the water column and bottom features directly beneath the linear transducer and the vessel on which the linear transducer is employed. Some other embodiments, in addition to the use of a linear transducer directed downward, also employ at least one sidescan transducer element 5 (e.g., a linear transducer oriented away from the side of the vessel) to ensonify (e.g., emit sonar pulses and detect echo returns) the sea floor on the sides of a vessel. Accordingly, better quality sonar images may be provided for the water column and bottom features beneath the vessel, of a quality that was unavailable earlier. Moreover embodiments of the present disclosure may simplify the processing involved in producing :0 high quality sonar images. - 3b - 9172742_l.docx 2015201220 10 Mar 2015

In one exemplary ernbodimentiiaiffensbu^ provided:,; The transducer arrayraay include a. housing and a linear transducer;: element. The housing may be mountable to a watercraft capable of traversing a surface of a body of water, the linear tfahsdueef element may be positioned within the housing and may haveb substantially δ rectangular shape configured to produce a sonar beam having abeamwidth in a direction: parallel to longitudinal length of the linear transducer element that is significantly less than a beamwidih otthe sonar beam in a direction perpendicularto the longitudinal length of the, transducer element. The iinear transducer element may also be posUioned; within the housing to project sonar pulses in a direction substantially perpendicular to 3 plane 10 Corresponding to the surface.

In another exemplary embodiment, a transducer array is provided. The transducer array may include a plurality of transducer element and each one of the plurality of transducer elements may include a substahtiatly recmngyiar shape configured to produce a sonar beam having a beamwidth in a direction parallel folongitudinai length 15 of the transducer elements that is significantly less than a beamwidih of the sonar beam in a direction perpendtcuiar to the longitudinal length of the transducer elements. The plurality of tran sducer elements may be positioned such that longitudinal lengths of at least two of the pluratlfy of transducer elements are parallel to each other. The plurality of transducer elements rnay also include: at least a first linear transducer element, a second 20 linear transducer elementand a third linear transducer element, the first linear transducer element may be positioned within the housing to project sonar puises from a first side of the housing In a direction generally perpendicular to a centerline of the housing. The second linear transducer element may be positioned within toe housing to lie In a plane with the first Iinear transducer element and project sonar pulses from a 25 second side of the housing that is generally opposite of the first side. The third iinear tr ansducer element may be positioned Within the housing to project sonar pulses in a diremicm: generafiy perpendicuiar to the piane, ip another exemplary embodiment, 3 sonar system is provided. The sonar system may include a transducer array and a sonar module. The transducer array may include a 30 plurality of transducer elements and: each erne of the plurality of transducer elements may include a substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallei to longitudinal length of the transducer elements that is significantly less than a beamwidth of the sonar beam in a bisection perpendicular to the longitudinal length of the transducer elements. The plurality Of transducer elements may 35 be positioned such that longitudinal tehgths of at least two of the plurality of transducer elements are parallei to each other; The plurality of transducer elements may also include at least s first linear transducer element, a second iinear transducer element and -4 2015201220 10 Mar 2015 a third linear transducer element. The first linear transducer etementmay be positioned: within the housing to project sonar pulses from 3 first side of the housing; In a direction generally perpendlcuiar to a centerline dilhe housing. The:second linear transducer : element: rnay; be positioned within the housing to lie in: a: plane with the first; linear 5: transdueef elemeht and project sonar pulses from a second side of the housing that is ;:generaiiy opposite;;Of theflrsi side. The third linear transducer element maybe positioned within the housing; to project sonar poises in a direction generally perpendicular to the plane. The sonar module: may be configured to enable Operable communicationiWithThe transducer array, :The::SOriar module may jiietutie a SOfidr Signal processor configured to: 10 process sonar return signals received via. the transducer array, and a transceiver configured to provide communication between the fansdecef array and the:8;0nsr signal processor. ΒίίΐΡ iSESCBiPTfiON OF THE #B/ER^L S!lVVS:OF THE PRAW!N:G(S} 15 Thepateht; or application file contains aftegst: one drawing executed in color.

Copies oflthis: patent: or patent! application pubiicafort: with color drawing(s) wiitbe provided by the UvS. Patent and Trademark Ojfice.bpoh reguesi and payment of the necessary fee.

Having thus described the invention tn: general terniSi reference will now be made 20 to the accompanying brav# are not necessarily drawn to; scale, and wherein:

Fits. 1 is a diagram illustrating ah example of a series of conventional transducer elements;: 1:0 arrayed to produce a:multibeam sonar system; iFiG, 2 illustrates a fan shaped beam pattern -pro<to^:W'lbie::iP0»f^ntionai muftibeam sonar system of FSG. 1 as the beam pattern is projected onto toe seabed; 25 FlfS. 3 is a block diagram of a conventional muttlbeam sonar System for the system shown in FI©, tj;

FtQ. 4 is a diagram sidescatn sonar system; FIG, Elsa baslobtoois diagfarniillustraiing a son system according to an exemplary embodiment of the present invention; SO:; FtQ: OsiS a diagram illustrating a more detailed view of a transducer array according to an exemplary embodiment of the present "Invention;

FtG. ?A illustrates a side view showing;a: beam pattern produced by the transducer array aocordingdO an exempiary embodiment of the present invention;;:

FiG. ?B illustrateso top:Vfew showing a beam pattern produced by the transducer 35 arfayaccotofngtoian oif invention; FIG. 8A |s;;3:;;;diagfam iilusfrattng a:cross settoonipfcomponents in a;containment volume Of a housing according to an exemplary embodiment of the present .invention: -5· 2015201220 10 Mar 2015 FIG. SB iea diagram illustrating a cross section of components in a containment volume of a housing according to another exemplary embodiment of the preset: invention; FIG. 9A shows an example of beam coverage for an 800 kHz operating frequency 5 in one exemplary embodiment of the present invention; FIG, BB shows m example of beamcoverage for a 455 kHz operating feequency in one exempiary emt^diment o? the resent invention; FIGi 10A iiiysirafes a projection, onto a substantially flat sea bed, of the beam pattern of an exernpiary transducer array providing gaps between fan shaped beams 10 produced by a transducer array in which transducer eiements are positioned to provide eopianar beams with gaps therebetween according to an exemplary embodiment of the present invention; RG; 10B illustrates a projection, onto a substantially fiat sea bed, of the beam pattern of an exemplary transducer array providing gaps between the fan shaped beams 15 produced by a transducer array in 'which the transducer elements are positioned to provide gaps with planar separation therebetween according: to another exemplary embodiment of the present invention;

FiG. 1 f A shows an example of a of the beam coverage associated with the exemplary embodiment of FIG. SA in which the beam coverage is extended to the bottom 20 of a fiat bottomed body of water according to an exemplary embodimem of the present

Invention;

FiG. 110 illustrates example sidescah Images that may be produced based on data from sidesean beams shown in FIG, 11A according to an exemplary embodiment of the pfeseniinventien; 25 FIG, 11G illustrates example linear downsean images; that may be produced based on data from linear downsean beams shown in FIG, 11 A;according to an iOxempiaiy embodiment of tire present invention;

FiG .: : 12A iilustrates example sidesean images tbatmay be: Dioducocl based on data from Sidesean beams; 30; FiG, 120 illustrates a side-by-side comparison of Images produced by a downsean linear transducer element according to an exemplary embodiment and a corresponding conical downsean image; FIG, 120 illustrates another side-biy-Side compansop/pf Images produced by a downsean linear transducer element according to an exemplar,' embodiment and a :3S corresponding conical downsean image; -6- 2015201220 10 Mar 2015 10: 15 RG. 12D illustrates stiff another side-by-side comparison of images produced by a downscan linear transducer element according ίο an exemplary embodiment and a corresponding conical downscan image; FIG. 12E iiiustrates yet another side-i^^side comparison of images produced by a downscan linear transducer element accordipf ίόίΟΡ oxempiary embodiment:and: a corresponding conical downscan: image; FIG. 12P fiiustrates yet still a^oher sido-^sfde comparison of images produced by a downscan lineairfransdcber element acCOrdingdoan exemplary embodimentand a corresponding conical downscan image; FIG. ISA ls e diagram: illustrating artiaxampIO Οί:0::$63 bottom: structure vlepm ibrougb a: linear dewnscap: transducer element accordlnglb an exemplary embodiment; FIG. 1 SB is a diagram illustrating :an example of a Ian shaped beam from a linear dbWnscah transducer compared to a conical beam from: a ^cylindrical transducer for the: sea bottom; structure illustrated in FIG. iGAecpofhtngrtp an exemplary embodiment; FIG. 14 Is a basic block diagram illustrating a sonar system according to an exemplary embodiment of the presentlfiventien; FIG. 15A illustrates an example oi::a:top yievvolthe beam overlap that may: occur: in sltuat!ons::wftere::a linear downSGan transducer and a Oimular: dowbscah transducer are employed accordibgi tc an exemplary embodiment of the present invention; 25 FIG. 158 shows side views of the same beam overlap shown in FIG, IS^frgm the: iSfatboard side of a vessel and from ahead of the bow of the vessel according to a n exemplar embodiment of the present invention; FIG. 16¾ is a diagram showing a perspective view of a iinear dowfiSGan transducer apd a circular downscan transducer within a single housing from a point above 25 the housing according to an exemplary embodiment of the present invention; FIG. 18:8 ts::a perspective View from one side of the housmg of FIG. l6Aat a point substantially perpendlcutarlp a longitudinal ax^s of the bousing according) an exemplary embodimanfpf iheipresent invention; FIG 16C is a perspective view from the front side of the housing of Fl G, 18A at a 30 point looking straight dbvvn thelpngitUdinal axisbftheiidtising according to an exemplary embodiment of the present invention;;

FlGiΊ7Α is a diagram showing a perspective view of a linear downscan transducer within a single housing from:s point above the housing according to an : exem piery embedimeht of th e present invenfion; 35 FIG, :#8 is a perspective viewffem oneaide of 100 housing of FIG, l7A.at a point substantially gerpendieuiar to a longitudinal axis of the bousing according to an exemplary embodiment of trie present invention; and 2015201220 10 Mar 2015

FiG 1?C is a perspective \iigw side of:, the Housing of FIG, fvMy aie: point looking straight down the iongSodthaiiaxiS of tiiie housingiuecorqilng to an exemplary: embodiment of the present invention. 5 DEI AS LED ά^.(ίϊ^ί^θΝ;:φ^:¥^^ϊ!ί^|ίΝΓΓϊρίΜ::

Exemplary embodiments of the present Inventionnow wilt be described merefuily hereinafter with Reference to the accompanying drawings, in ^Ι^.·«3ΐΐί^,;^:Ρί^:Μ: embodiments o? the invention are shown, indeed, fhe invention may be embodied in many different forms and should not be construed as limited to the exemplary 1() embodiments set forth herein; rattier, these disclosure will satisfy applicable legal requirements- Like reference numerals refer to like elements throughout, FIG. 5 is a basic block diagram iliustraifng a sonar system 30 for use with multiple exemplary embodiments of the present Invention. As shown, the sonar system 30 may 15 include a number of different modules or components, each of which may comprise any device or means embodied in either hardware, software, or a combination of hardware and software configured to perform one or more corresponding functions. For example, the sonar system 30 may include a sonarsignai processor 3¾ a transceiver 34 and a transducer array 3S and/or numerous other peripheral devices such as one or more 20 displays 3S, One or more of ihemoduies may be configured to communicate with one or more of the other modules to process and/pr display data, information or the like from one Or more df the modules: The modules may aiso be configured to communicate with one another In any of a number of different manners including, for example, via a network 40. In this regard, the network 40 may beanyof a num ber of drdereht communication 25 backboneSibr framevmfks-ifiGi^ Ethernet, the NMEA28QO:f5ramewerkor

Other suitable networks..

The display 38 may be configured to display images and may include or otherwise be in communication with a user interface 39 configured to receive an input from a used the display 38 may be, for example, a conventional LCD (liquid crystal,display), a touch 30 screen display, or any other suitable display known in the art upon which Images may be rendered. Although each display 38 of FIG, 5 is shown as being-connected to the sonar signal processor 32 via the network and/or Via an Ethernet hub, die display 38 could : alternatively be in direct communication with the sonar signal processor 32 in some embodiments, or the display 38f: sonar signal/ processor 32 and user inferface 39 could be 36 in a single housing. The ussr ihtetfUoe 30 may Include, for example, a keyboard, keypad, .function keys, mouse, scroiiing device:, Inpebouiputporis, touch screen, or any other 4 2015201220 10 Mar 2015 mechanism by which a user may irUerface with the system. Moreover, in some cases, the user interface 36 may be a portion bf one or more ofihe displays 38.

The transducer array 36 according to anexempiary embodiment may he provided in one or more housings that providefor ilexibiemountiny with respect to a hull of the 5 vessel on which the sonar system 30 is employed. In this regard, for example, the 'housing may be mounted onto the: hull of the vessel or on!Q;a;b©yib© or component that may be attached to the buif {e.g., a trolling motor or other steerable device, or anot w component that is mountable relative to the huil of the vessel}. Including a bracket that is adjustable on multi pte;pxes,: permitting omnidirecfionat movement of the housing. the; 1:0 trahsduper array 36 maylhetude one or more transducer elements: pcesfiohed within the housing, as described irsiigreater detail below, and each of thefransdueer elements may be configured to be directed to cover s different: area such that one transducer element covers one side of the vessel with a fan shaped beam, another transducer element covers; the opposite side of the vessel with atfan shaped beam, aRdlhe thfrdi fan shaped 16 :beam opyers a region between the other transducer elements directed below thp vessel · in an exemplary embodiment, each pf the Transducer elements ofihe transducer array 36 may be substantially identical in terms of construction and therefore: may be different only by virtue of the orientation of the respeetiveirsnsducer elements. The transducer array 36 may be configured to both transmit and receive sound pressureiWaves, However, in 2d some cases, the transducer array 36 could include separate elements for transmission and reception,: Th©: transducer array 36 is described in greater detail below in reference

Ib ah exemplary embodiment, the sonar signs! processor 32, the transceiver 34 and ah |fhern©ti hub 42 orother network hub may form a sonar modute 44. As such, for 25 example, in some cases, the transducerarray 36 may simply he piaced into communication with the sonar module 44, which; may itself be a mobile device that may be placed (but not necessarily mounted in a fixed; amangement} in the Vesset to permit easy installation of one or more displays 38, eacbiofvVbich may be remotely loeatod; from each other and operable independent of each other. In this regard, for example, the 30 ithemef hub 42 may include onSiOr mOr© corresponding interface ports for placing the ;iifeltoofk!'4'0i.dljgpay 36 in© piug-n-play manner. As such, for example, the liternet ;pdi'db|yib^di':INt:'bardware needed to enable the displays 38i to b© plugged into communication with the network 40 via the Ethernet hub 42, but the1 Ethernet hub 42 may aisonnciude or otherwise be in communication with 35 software modules for providing information to enable the sonar module 44 to communicateyvith one dr more dihefentiinstances iof the display 38 that may or may not be the same mode! or type of display and: that may display the same or different -δ- 2015201220 10 Mar 2015 information. In other words, the sonar module 44 may store configuration settings defining a Redefined set of display types with which the sonar module is compatible so that if any of the predefined set of display types are placed into communication with the sonar module 44, the sonar module 44 may operate in a piug-n-play manner with the 5 eorresj^hding display types. Accordingly, the sonar module 44 may include a memory sfodhg; device drivers accessible to the Ethernet huh 42 to enable the Ethernet hub 42 to properly work with displays for which is compatible. T he sonar module 44 may also be enabled to be upgraded with additional device drivers to enable expansion of the numbers and types of devices with which the sonar module 44 may be 1Q compatible. In some cases, the user may select a display type to check whether a the display type is:: supported and, if the display type is not supported, contact a network entity to request sofhvare and/or drivers for enabling support of the corresponding display type.

The sonar signal processes 32 may be any means such as a device or circuitry opeFating in accordance with software or otherwise embodied in hardware or a 15 combination of hardware and software (e.g., a processor operating under software control or the processor embodied as an application specific integrated circuit (ASIC) or field programmable gate array fFPGA) specificallyconfigured to perform the operations described herein, er a combination thereof} thereby configuring the device orcircuftry tG perform She corresponding fMhctiphS of the sonar signal processor 32 as described 20 herein, in this regard^ the sonar signal processed may he configured to analyze electricaI signais eammunicated thereto by the transceiver 34 to provide sonar data indidaiive of ihd SizeyloCatidn, shape, etc. of objects detected by the sonar system 30, Sn some cases, Ithesdhatsigdal processor 32 may include a processor, a processing ©{embnb a.CopRCcessohra: centr oiler or various other processing means or devices 25 including Integrated circuits such as, for exampie.an ASIG; FPGA or hardware acceieraiori that is configured to execute venous programmed operations or instructions stored in a memory device. The sonar signal processor may further or alternatively embody multiple compatible additional hardware or hardware and software items to implement signal processing or enhancement features to improve the display 30 characteristies or data or images, collect or process additional data, suchastime, temperature, GPS information, Waypoint;design^atiohs, or others, or may filter extraneous data to better analyze the collected defa, If may further implement notices end alarms, Such as those determined or adjusfed by a user; to reflect depth, presence of fish, proximity of other watercraft, etc. Still further, the processor, in combination with suitable 35 memory, may store incoming transducer data of screenlmages for future playback or transfer, or alter images with additional processing to implement zoom or lateral movement, or to correlate data, such as fish or bottom features to a GPS position or ‘10- 2015201220 10 Mar 2015 temperature, in an exemplary embodiment, the sonar signal processor 32 may ekeoyte available f^r contrpiM^g th0 transceiver 34 and/or transducer array and for processin§;bsta received therefrom Further sapabltities of the sonar signal processor 32 and other aspects related to the sonar module are-described in D.S, Patent 5 Application Serial Mo.__., entitled “Linear and Circular Oownscan im aging1

Soriar" filed on even date; herewith, the disclosure of which is incorporated herein fey reference in its entirety.

The transceiver 34 may:be any means such as a device or circuitry opepingdn : accordance with: software or otherwise embodied:: in hardware or a combination of 10 :hardware and software (e.g., a processor operating:under boliwafe control or the; processor embodied as ap: A$jC or FFGAspecificaily configured to:perform the pparatipns described herein,: or arcombination thereof) tnereby configuring the device or circuitry toperform the corresponding 'functions of the transceiver 34 as described herein, in this regard, for example, the transceiver 34 may include circuitry for providing 15 transmission electrical signaiSTo the transducer1 array 36 for conversion to sound presswre slgnaiSfeased on the provided electrical signals to be transmitted as a sonar pulse. The transceivoi 34 may also include circuitry for reeuvmg electrical signals produced-by the transducer array 36 responsive to sound pressure signals received at theIbansdyear array 36 based on echo or other return signals recervedin response to the 20 transmission of a sonar pulse, IfteiiansoeiveriiSI may be in communication with the sonar signal processor 32 to both receive instructions regarding thetransrnissicn of sonar signals and to provide information on sonar returns to the sonar signal processor 32 for analysis and ultimately fdr driving one or more of the displays:38 based on the sonar ireturns:. 26 FIG. 6 is a diagram illustrating a more detailed view of ihe transducer array 36 according to an exempiafy embodiment. As shown in FIG. 6, the transducer array 36 may include a housing 50 that may include mounting h<Ses 52 through which screws, rivets, bolts or other mounting devices may be passed in order to fix the housing 50 to a mounting bracket, a devsceattached to a vessei or to the huii of the vessel itself. 30 However, in some cases, the housing 56 may be affixed by welding, adhesive, snap fit or other coupling means. The housing 50 may be mounted to a portion of the vessel, or to a device attached to the vessel, thatprovides a relaSveiy unobstructed view of txjth sides of the vessel. Thus, for examine, the housing 50 may be mousted on or near the keel (or centerline) of the vessel, on a fixed dr adjustable mounting bracket that extends below a 35 depth of the keel (or centeriine} of die vessel, or on a mounting device that is offset from the bow or stem of the vessel. The housing 50 may induce a recessedportion defining containment volume 54 for hoiding transdpoer eiemenfe 60, The: recessed portion •11·· 2015201220 10 Mar 2015 defining the eohisirimpht volume 'may extend away from the hull of the Vessel on which the housing 50 is protrude into the water on which the vessei: operates: (or in which iheyessetpperates in a paseiVWhereiithe trBnsdMcer array 36 is mounted ip a tow fish). To prevent cavitation or the production of bubbles due to uneven 5 flow over the housing: 50, the housing 50 (and impariicuiar the containment volume portion of the housing) may have a gradual rounded or otherwise sfrearn!tned profile to permit laminar flow of water overthe housing 50. in some exampies, an insulated cable 58 may provide a conduit for wiring to communicatively couple the transducer elements 60 to the sonar moduie 44. 10 15 20 25. 30 35

Each of the transducer elements 60 may be a linear transducer element. Thus, for example, each: of the transducer elements 60 may be substantially rectangular in shape and made from a piezoelectric material such as a piezoelectric ceramic material as is well: known in the art and may include appropriate shielding (not shown) as is we!! known in the art. The piezoelectric materia! being disposed in a reetanguiar arrangement provitesfor an approximation of a linear array having beamwidth charact&amp;'istics that are a function of the length and width of the reetanguiar face of the transducer elements and the frequency of Operation: In an exemplary embodiment, the transducer eiements 60 may ibe configured to operate Jn-aPoPrdinPe^h-iSt'-fiRasi.iwo operating frequencies. In this regard, for example, a frequency selection capability may be provided by the sonar Imodule 44: to ehabie the: user to seiect ohe plat1 ieast two frequencies of operation. In one examplevone operating fredueheyimay^besset: fpidbopt·:|O0::k:Hz and another operating frequency may be setlo about 4:SSskHz. Furthermore, the length of the transducer eiehiehts may be set to about 520 mm while the Width is set to about 3 mm to thereby produce beam characteristics corresponding to a bearing fan of about 0.8 degrees by about :32 degrees at 800 kHz. er about 1.4 degrees by about 56 degrees at 455 kHz. However, in general the length and width of the transducer elements 80 may bd set such that the bearfrWidth of sonar beam produced by the transducer elements 80 in a direction pafaiio! Ip a iongitudihdilehgfhlt) of the transducer elements 60 is less than about five percent as largeias fhe::beamwidth:te team in a direction (w) perpendicular to the longitudinal length of the transducer elements 60, (See generally FIGS. 7A, 7B, 9A, 98i) it should be noted That although the widths of various beams are shown and described herein, the widths being:referred to do not necessarily correspond to actus! edges defining limits to whore energy is piaced in the water. As such, although beam patterns and prejections ofibeam: pahems are generally shown herein as having fixed and typically geometrically shaped boundaries, those boundaries merely correspond to the-SdB (or half power) points for the transmitted beams, in other words, energy -t >y 'AT: 2015201220 10 Mar 2015 measured outside of the boundaries shown is less than half of the energy transmitted. Thus, the boundaries shown are boundaries.

Aithoygh dual frequency operations providing a specific beam fan for each respective eiemeht for given lengths are: describedabove, itsheuid be understood; that ;§ other operating ranges could aiternativeiy be provided with corresponding different transducer element sizes and corresponding different heamwidth characteristics. : More over, ih some cases, trie sonarmodule 44 may include a variable frequency iselecfofoto enable an operator to select a partieular frequency oi choice for the current opefaithg eOhditiohs. However, in ail eases where the longitudinal length of the 10 transducer elements 60 is general/ aligned with the centerline of the vessel, the rectangular shape of tire transducer elements 60 provides fora narrow beamwidth in a direction substantially parallel to the centerline ofthe vessel and wide heamwidth in a direction substantiaiiy perpendicular to the centerline ofthe vessel. However, if the transducer array 36 is mounted; in a differentfashion prig a rotatable accessory on the I S vessel (e.g,, a trolling motor mcwnt}, the fan-shaped beams,pxxtuced will have the wide beamwidth in a direction substantially perpendicuiar to the fongitudina! length ofthe transducer elements 60 and a narrow beamwidth in a direction; substantially parallel to the longitudinal length ofthe transducer elementsiO. Thus, the s<Miar could also be oriented to provide fore and aft oriented fan-shaped beams or any other orientation relative to the 20 vessel in Instances Where motion of the vessel is not necessarily in a direction aligned With the centerline of thai:vessel RGS. 7A andiS show siderand fopyiewsr:fespectiyely, illustrating the beam «haracteristjcs;ipredqced;,by an; exempiaty embpdimentdf thepresent invention. In this regard; fig^TA illustrates a side, view showing the:transducer array 36 mounted to a 2S bracket that e)dehds;iromdhe: aft end of the centerline of fheivassei (e.g., boat):. As shown in FIG; 7A, the beam produced by the transducer array 36 is relativel^rhafrew in tire direction substantially paraiiei to the cehterilhe of the vessel if the transducer elements are aligned for a generally oopianar beam. FIG, 7A also includes:a cutaway view of the trartsdueebaffey::^ of foe transducer elements 60 in 30 context relative to the; vessel : accordlhg to this example. IVleahWhiSe, FIG:, TS shows: a fop view of the beam produced by the transducer assembly 36 if the transducer elements are aligned for a generally coplanar beam;. As shown In F!G. 7B, the beam produced by the transducer array ··$ relatively wide iri: foe direction substantially perpendictilarfo the centerline of the vesseiitherebyiproduoing a fanTShaped Mamipatterh extending out to. 35 both sides: and aisoeeyering: the:water cplumh beneath: the: vessel, as described below, FIG. 7B also includes a cutaway view #fo:e transducer array 36 to: show theenentafion of the transducer elements bOlhconfoxt ifeiativa to the vessel accordsngfo this example, -13- 2015201220 10 Mar 2015 BIS. 8A is a diagram illustrating sicross sectionofcomponents in the containment ivotume;54 according |<J:an exempid^oriiljpdiment. ilRigartiouiar, Ft<3, 8A illustrates the arrangement of the linear transducer eiements 60 wjihihiitho containment yolume 54. The transducer elements:®!):, Which may include a port side element 62 positioned to scan 5 isubstantiaity to the port side of the vessel, a starhoafd side element: 64::p0sffionedTb scan: subsianflaliy to the starboardiSid© of th© vessel, and a downsean element 66 positioned to scan substantially below thelvessei,: As shown in FIG. 8A. in an exemplary embodiment, both the poolside:element 62 and the starboard side; element: 64 may be oriented to face slightly beiow a surface of the water on which the vessel travels. In on© 10 example, bothithe port side element 62 and the siarboaid:S:ide eiemantfBmay be oriented isoeiTthat the wi destdimerisfon of the besmpdfh of each respective element is eentered:aT30: degrees below a plane substantially parallel to the surface of thewater. 'Meanwhile, the downsean linear element 66 may be positioned such that the widest; dimension of the beamwidth of the downsean ei©ment 66 is centered at 90 degrees below 15 the plane substantiaiiy parallel to the surface of the water, in other words, the downsean element 66 has the central portion of its fan shape aimed straight down. The containment volume 54 may include electrical connections (not shown) to communicate with the transceiver 34 and supports, struts, rods or other supporting structures to secure each of the linear transducer elements 60 -n their respedtiy© orientations. The transducer 20 elements 80 may be held in place or otherwise affixed to the supporting strucfures yie adhesiy© or any other suitable joining materiai and the angles at which the transducer ©ierhertfs iOare affixed relative to eabb other and to the housing 50 may vary as necessary or as desired, $113: 6B is a diagram illustrating a cross section of components in the containment 25 volume: 54 according to an alternative exemplary embodiment. In this regard,iiF IG, SB illustrates:·the arrangement of one linear transducer element-60 wiMn th© :containment volume: 54> 'fhe .transducer element 60 according to this exemplary embodiment fee .single linear transducer (e.g,, downsean element 66) positioned below the vessel. As shown in BIG. BB. ihe downsean element 66 pay be:positioned 30 such that the: widest dimension of the beamvvidth of the downsean element 66 is: centered at 90 degrees below the parte substantially parallel to the surface Of fhelwateb In other1 words, the d:bwhscan:::eiement::68::has the central portion of its fan shafmdimed: substantially straight down. As discussed above, the containment void me 54 may indlude Centrical connections {not shown) to communicate with the transceiver 34 and supports, 35 sfruis, rods or other supporting structures Insecure the downsean element 66 in its respective orientation. The linear downsean element 66 may be held in place or otherwise affixed to the: supporting struct ures via adhesive or any other suitable joining 14 2015201220 10 Mar 2015 material such that transmissions produced by the downscan element 66 exit the housing: SO substanbaiiy ai a tG degroe angle with respect ίο the plane of the face of the downscan element 56 from which the transmissions:emanate,

FiG. 9A shows an example of beam OoVeragelor ah;B00 kHz operating frequency 5 ip one exemplary embodiment. As such, tbebeamwidth.{erg., width between the half power points) of each of the three linear transducer eiemente· 60 is about 82 degrees. FIG, SB shows abexample of beam coverage for a 45&amp;KH2 operating frequency in one exemplary embodiiiehb thereby providing about 56 degrees of beamwidth for each of the three linear transducer ©iemenis 60, Accordingly, fmeaehof the exemplary embodiments 10 cFFIGS, 9A and 98,the three fan-shaped segments: together produce; asdiscontlnuous fan shaped beam. The discontinuity may b© minimized in some instances by selection of transducer eiementdimenssons and operadhglrequehcies selected to minimize the size, of the gaps re.g , 2pne8With sonar beam coverage outside of beam coverage area as defined by the half power points of the beams) between the beams of the transducer 15 eiements. Alternatively; the physical orientation of the transducer eiements:60 with respect :tb each other cpuid be changed in order to minimize the size of the:gaps. HpweveA it should be doted that in most cases::some gap should bejmalhtajned in order to prevent interferenceb^ween the beam: patterns emanating from:: the iiheaf transducer elements 60 Aithough ths fan-shaped segments of an exemplary embodiment may ali lie 20 In the same piahe:; it may be deSirabteto: alter the orientation of one or more of die transducer elements 60 such :th3t; 3: Corresponding: one oi' more of hie fan-shaped segments is puiside of the piarie of the other fan-shaped segments. Thegap could therefore bo provided via planar separation o‘ the fan-shaped segments ratherthan by providing separation:between the segments within the same plane. 25 in this regard, FIG, 10A illustrates a projection, onto a substantially fiat sea bed, of the beam pattern of ah exemplary transducer array providing gap# between me boundaries of the projections as defined by the half power points defining fan shaped Beams produced by a transducer array in which the transducer elements 60 are positioned to provide copianar beams with gaps therebetween according to an exemplary 36 embodiment. As such, a first transducer element beam projection 100, a second transducer element beam projection 102 and a third transducer element beam projection 104 are ait shown lying in the same plane tn F;G. 10A. Meanwhile, FIG. 10B illustrates a pto)ecSbn, onto a substantially flat sea bed, of the beam pattern of art exemplary transducer array providing gaps between the Ian shaped beams produced by a 35 transducer array in which lie transducer elements are positioned to provide gaps with planar separation therebetween according to another exemplary embodiment. Thus, the first transducer element beam projection 100’. the socond transducer element beam -15- 2015201220 10 Mar 2015 projection 102’ and the third traosducereiemeni beam projection 104: are shown tying in different pianes in FIG. 10B. Notably, ineachof FIGS. lOAand 10B, the view is shown from the top looking down onto the sea bed and the beam projections: are not necessarily to spate. 5 FfG. IIAshows an example of a view of the beam coverage associated with the embodiment of the example shown in FIG. SA in which the beam coverage is: extended to the bottom of a flat bottomed body of water. The illustration of FIG. HAshowsa view looking at the stem of a vessel 70 as die vessel 70 is driving away from the viewer (e.g., into the page). According to this exampie, a port sidescan beam 72 {e.g., that may be 10 produced by port sidescan element 62) extends out to the port side of the vessel 70 providing coverage of the bottom from point Ate ρωηί B:. Meanwhile, a starboard sidescan beam 74 (e.g., that may be produced by starboard sidescan element 64} extends out to the starboard side of the vessel 70 from point C to point D. Additionally, a downscan beam 76 (e.g., that may be produced by downscan element 66) extends 15 directly below the vessel; 7Q:from point E to point F. As; shown in FiG. 11 A, the coverage areas defined between points-A and-¾ andpainfe Gand D are substantially larger than the coverage area defined^ bshveen poinis E and F. Based on the increased bottom coverage, the display provided responsive to data received in the sidescan beams 72 and 74 will be different than the display provided responsive to datareceived in the downscan 26 beam 76. FIGSt118 add 11C sh ow· examples of images that may correspond to the beam coverage; areas shown in FIG ,1lA, in this regard, for example, FiG. 11B illustrates possible images that could correspondfo the region defined between points A and B and points G and D (e.g.. sidescan images}, while FIG, 110 illustrates a possible image that may eoffetetetodbecoverage area between points E and F (e.g., a lineardownscan :25 image),: FIGS, 12A through 12F show examples of images that may be produced by embodiments of the present invention tO iiiOStrate differences between the display produced by a linear downscan element :(S an embodiment of the present invention and either a sidescan or a conventional circular downscan transducer element, in this regard, 3D FIG. 12A illustrates an example image that may be produced based on data from the sidescan: beams 72 and 74. For this example, assume the top of the display (identiied by arrow 80) shows toe most recent data (e;g., corresponding to the vessel's current position} and the bottom1 Of the display (identified by arfsyv^;'&amp;2)y?^0V!^tt^e-:taij!cii!@§it--daia.· Additionally, the right side of the display 84 may correspond fp the starboard eidescan: 35 beam 74 while the left side:of the:display 86:corresponds to the port sidescan beam 72. Brighter pixels illustrated ifrFIG. 12A correspOrtd:to retorh: data received id the corresponding sidescan: beams, in this regard, data idlosest to dashed Sine;8$ 16- 2015201220 10 Mar 2015 corresponds to the data gathered near point B (for the left side of the display 88) and near point Dff bribe· right side of the display 84) and data at the left edge of the display pxiint right edge of the display corresponds to data gathered near point C over the it me period from tire position of arrow δ 82 tpithp:position Pf arrow 80, Thus, welt over ofth® display FS3,12A (and in many cases 100%) Is utilizeditosbow data corresponding to bottom features, e-S· the topography of and structures attached to the bottom, that have provided return data from thepIdfeedae'il^adi^iiT^'^nd·?^ By comparison only a small portion (s.g,, less than 20%) of the: display Shows any water column features, :®)g ;:,. data; from the water column: 10 between the vessel 70 and the portions of th® pplbm cpvpred by each respective sidescan beam. The sidescan beams 72 and 74 also fail to provide depth data. Still further, the Sidescan beams fail to provide depth data: or bottom: feature data or water eoiumrbddia fpf thaf pphiph pf theihottQrrt beneath the vessel, e>g.s that portion ibelweeb reference points B and :D and the vessel 70 in Fl;31i, 15 FIGS. 12B through: D2F show on the right side:(θ.®,, right display 90) of each figure, exemplary screen shots pf a conventidhai eiroutaf downscan transducer image that the left side of each figure (left display 92)) produced by the linear dowhscanielement of:an:embodiment ef the presentinvention (e.g., downscan element 88). in this regard, the left display of FfG. 12B shows abouider on the left, two 20: free ) trunks rising up from 'the bottom: near the center of the display, and, possibly, several fish (white spots) near the lower right. The Corresponding same features can be vaguely determined from the right display SO (1.0,, the circular downscan display), but the images are much less ciesr. Similarly, FIGS, 123,12D and 12E clearly show very detailed images of trees rising.vertically from the bottom in the left display 82, while such features 25 are very difficult to distinguish on fhe right display SQ. FIG: 12F clearly shows a downed treei ahd at least two vertical trees nearby: in the Safi display 92, Whereas the: same features: are difficult to: discern In the right display 90.

The exemplary linear downscah image on the leftpfde of FIG. 128 includes a numerical depth scale (M0 on the right side, win sonar reflection data being represented 30 on the display screen at the time-dependant ucoth using known sonar imaging practices.. Boat position Is represented by the numeral C or some ether desirable icon, for the most recent sonar pings, and the oldest sonar pings are presented by the ieh side: Qf the screen, presenting a scrolling image as the beat (and fransducerymeVe across the Water surface oyer time. The far right columurefiects the intensity of the return echo: received 35 at the circular down scan transducer, pipfted adjacent trie S5-40 depth scale.

Accordingly, by placing a linear transducer in 3 downward: oriented position, a much impfoved Image quality is achieved pr bottom date and structures attached to it or -17- 2015201220 10 Mar 2015 35 rising above it relative Ip the conventional circular downscan sonar. in this regard, white sidescan images are valued ter their ability to provide detailed images of laterally distant feotfemfe^^ to provide depth data or bottom data or water column

A linear downscan element provides the unexpected advantage of 5 providing detailed images of the wafer column: beipw the vessel (eg., upwardly extending submerged dees, fish, etc,), as or sifUctuiBS resting on or rising above the bottom (e.g., rocks, crevices, submerged trees, sunken: objects, etc.), and a depth indication that can be registered (e.g., feet or meters). For pxampie. again referring to the left image of FIG. 128, the mass of bright pixels si about 10 30 feet (asindicated by the numbers in increments of five feet that extend down the right edge of the left display @2) represent bottom feature data and ate indicative of the depth at which the bottom is endpuritered. The bottom feature data may also, in some cases, indldate the type pfsboifem fe:.g., rocky; muddy, hard, soft, flat, sloped, smooth, rough, etc.), f bus, sonar feturns associated with the bottom in a iinear downscan display are I S not oniy indicative of bphom features, but are also indicative of depth and water column data. However, the bottom feature data represents a refailvely smaif pfeentage of fee Overall display area. Due to the relatively small percentage of display areadhai is: devoted to bottom feature data, a relatively large percentage of the display area may be devoted to other data, e.g., data representing the water column above the bottom), Thus, 20: for example, as shown m FIG», IlSB,'water column faatdfes are represented by data, including a boulder and trees extending from the bodom: along with any suspended objects {e.g,:, schools of bait fish, individual iargelishj Oic,), tbermpciihes;, and ofeeF1 features may be displayed in greater detail along with the indication of bottom depth. Mearivvhi!Ο* dvin f ri situations: where: the zoom level of the dismay is not set such that the 25 tele·:pf::Sea:'bottom(Is;'hear the lowest portion of the display (such as in FIG. 12G), the bottom features only account for a small percenfage of the display area, while the wafer column features account for more than 50% and the area below the Sake or sea bottom is esssritialiy featureless. FIGS. 128;through 12F each show far less than §0% land typically less than 20%) 30 of the display being utilized to show data corresponding to bottom feafures. and do so for thp: water column beneath the vessel. As; shown, a iinear transducer positioned as a downscan element (e.g,, downscan element 66} according to an exemplary embodiment, is capable of providing far more information regarding the Water column itself rather than merelythefeotfdm feafefes or depth. Thus, wafer column data can be received arid displayed representing schools of fish, individual fish and certain struciural features in the water Column directly below the vessel 70. Additionally, as shown in FIGS. 12B throdgh 12F, a linear transducer positioned as a downscan element is aiso capahie of producing -18- 2015201220 10 Mar 2015 depth, data. in this regard, whereas a sidescan image produces relatively high quality imagesoffeatures (see for; example,: FiG. 12A), it is UfiQbl© tdi produce useful depth data; or wafe r colum n data. A: dpwnsceo image produced by a^ transducer according1 to arvexempiary embodiment of th© pfesent inventicsn produces depth data 5 along with bdtiOW: feature data and water column data. FIG 13A provides an example of % display of the bottom structure as viewed through;ij^Q of a Mnear downseart sonar element (e.g., downscan element 88} ofan exemplary' embodiment of the present invention. FIG; 13B shows the vessel 70 and various bottom features viewed from above,: The bottom features mclode a boulder 120, 10 a: verticaf tree 122, a rock pile 124, a! school of fist? 1:26 and aifatleh, hwizontal ltree 128,

FtG,: iSS also shows a iinear iransducer downscan fsmsheped'Spoarbeam 430: projected: onto the bottom as compand to a circulartransdocendo^^ 132 projected onto the bottom. As can be appreciated from: the corresponding: example display provided In FiG. ISA, sinceihe linear downscahbeam 130 has a narrow' aspect in 15; pnedirection and a broad aspect in the other, the amount of data received and therefore processed for display Is less with respect to each feature for which a return is received than for the conical beam 132, There Is typically no overlap in coverage from each outgoing sound wave to the next (ping to ping}: in the linear downscan beam 130 whereas there will be such overlap in the cbnibai beam 132. Thus, while data corresponding to the 20 conical beam 132 Is processed, it produces blurred images due to the additional return data: received- the linear downscan beam 130 is able to produce “cleaner images that more aecUfately illustrate feature data that reflects what objects are in the water column and ph the bottom beneath the vessel. Note, however. that there can be atleast partial overlap in the bottom topography that Is sonified by the linear and circular transducer, as 25 shown In FIG. 138.

By providing the downscan element 66 as a Unear transducer element Of the same type and construction as one or both ci the port: side Itneaf eiement 62 and the starboard side linear element 64, embodiments of the present Invention provide vivid images of the column of water over which the vessel -^rid images of the: 30 water column on both sides of the vessel, which is provided by conventional sidescan sonar systems that either neglect the column of Water beneath the vessel or only scan such region with abonicai beam from a transducer element having aeyJinddcai shape that is not capable pf providing the level of detail provided by embodiments of the present invention. Moreover, embodimentsof the preseni invention provide 'high duality images 35 otthe column of water1 over which the vessel-passes without; the high degree of complexity iand costassociated With: a muitibeam system. -13· 2015201220 10 Mar 2015 FIG, 14 illustrates an exemplary sonar system incorporating linear and circular downscantransducers 140,142. The two transducers may be in the same or separate housings. They typically utilize different operaii<^ai #eguencfes. Such may also assist In minimizing interference. Simiiar to the system illustrated in FIG, 5, the transducers are 5 operationally connected to the ^ii^eivei«:)l44,.:14e,:yiitildi configure the transducer outputs for receipt by the sonar signal processor 148. The sonar signal processor executes various programs stored or as may be selected by the user interface 150. the: Ethernet hub 152, netwbrfc 154, displays 156 and user interface 150 operate as described fbrthe cepesponding compidhehfs of FIG 5. The image processor 158 may perform a 10 variety of functions to optimize or customize the display images, including such features as split screen to showmuitipfo different sonar images or data. Examples include individual and separate images of GPS, waypoints, mapping, nautical charts, GPS tracking, radar, etc., which aretypically shown side-by-side or stacked. Additional exam pies include individual data boxes, such as speed, depth, water; temperature, range 15 or distance scales, iocation or waypoint, latitude, longitude. dme^ etc.: Still further exam pies Include composite images 'that combine information from one or more of these sources, such as the images from the linear downstream and circular downstream transducers to overlay the images. For example, the traditional *fish afchTimage representing a possibie fish using a circular downscan sonar may be imposed over a 20 small white cirde or ova! representing a possible fish using a linear downscan sonar,; St® further, one image may be colorized to distinguish it visibly from data representing another image, As such, few- example, the images may be combined using image binding or overlay techniques, Alternatively, individual images may be presented, of different images, simullshaeusiy on different displays: Without overlay. Image data 25 packets or streams may also have additional data: associated therewith, such:: as time of day, location, temperature, speed. GPS, etc.

Notably, the example of FIG. 14 may ^©simplified id some embodiments. In this regard, the radar, mapand GPS modules of FIG. 14 along with the Ethernet hub 152 may not be included: in some embodiments. Moreover, Jri one example, an embodiment of the W present invention may include essentially oni| pfocessihg circuitry to handle inputs from a linear and circuiar transducer array along with a display taasingie device. As such, for example, aii of the electronics for handling linear and circuiar transducer inputs may be Include d along with a display wi thin a singlet box, withouf spy Ethernet: connection or other peripherals. 35 FIG. 15A illustrates'an example of atop view of the?beam overlap that may occur in situations where a linear downscan transducer and a circular downseah transducer are: employed simultaneously FIG. 1SB shows side views of the same beam overlap shown -20- 2015201220 10 Mar 2015 in FIG, 15A from the starboard side of a vessel (on {he left side of the page) and from ahead ofthe bow of the right side of the page}. As shown in PIG, 15A, there is overlap between a conical beam projection:I SO showing an example coverage area of a beam produced by tie cifeutaridownsean transducer and a downscan beam projection 182 showing an exampie^ooueragp area Gf a ibeam pri^Miced by the linear down scan transducer. The differences between the beam patterns of the linear and circular downscan transducers are further illustrated in FIG:,: 15S inwhich it can be seen:: that the beamwidth 184 of the beam produced by the circular downscan transducer is substantially the same regardless of the side from which the:beam is viewed. However, 10 the beamwidth 186 of the beam produced by th&amp;Jinear downscan transducer as viewed from: the starboard side of the vessel Is substantially smaller' than the beamwidth 188 pf

: th© beam produced by the linear downscan transducer as viewed from ahead of the bpw of the vessel Moreover, the beamwidth 188 is wider than the beamwidth 184, while the: beahiwidth 186 is narrower than the heamwidtblSA I S FIGS. 16A through 16G iftustrate diagrams of a linear dawnscan transducer ISO and a circular downscan transducer 192 within a single sfreamiined housing 194; from various different perspectives, in this regard, FIG. 16A is a perspective view from above the housing 194. Meanwhile,, FIG. 19S is a perspective viewfhsm one side of th© housing 194 at a point substaniiaSiy perpendicular to a ldngitudinai axis of the housing 194 and 2D FIG 16C is a perspective view from the front side of the housing 194 at a point looking siraighidownihe longitudinal axis of fhe housing 194, As shown in FiGS. IdA-iBC, the linear downscan transducer 190 and the circular downscan transducer 1S2 may each be disposed to; be in planes that are substantially parallel with each other arid With a plane in which the longitudmalaxis of the housing 194 ties. Generally speaking, the linear 25 downscan transducer 190 and the circular downscan transducer 192 may also be displosed in line WIth 194,: Although shown In a particular order in FIGS. 16A-1BG, the ordering of the placement of the linear downscan transducer 190 and the circular downscan transducer 192 vwthin the housing 194 may be reversed In some examples. furthermore, in some cases;, the linear downscan I3&amp; transducer 190 and ihecircuiar downscan transducer 192 may each be located in their own respective separate;housings rather than both being within a single housing. FiGS. 16A-16G also illustrate an: example Of a: mounting device 196'for mounting the; hb using 194 to a vessel

By woy of Comparison, fiGS- lTAlhrough 17C illustrate diagrams: of 3 single 35 linear downscan transducer 190: a housing 1:98: from various: different perspectives. In this regard, fig. f?A is a: perspective yiewftomts^^ 198. MeanwHiie, FIG. 178 is a perspective view from one side of the hpusihg: 198 at a point: substantlajiy -21- 2015201220 10 Mar 2015 perpendicular to a longitudinal axis of the housing 198 and FIG Γ/C is a pempective view from the front side of the housing 198 at a point iooking straight down the longitudinal axis of the housing 198. As shown in FIGS. 17A-17G. by employing only the linear downscan transducer iiSthe size eflibe housing 198 may be reduced, in this regard, for example, 5 particutarSv FIG. 17G shows a reduction in the cross sectional size Of the housing 198 as compared to the cross section ad size of the housing 194 of FiG. 180, thus, for example, the housing TS8 may introduce less drag than the housing 194,

Many modifications and :Oiher embodiments of theInventions setiforthfierein will come to mind to one skilled joTheiad to which '.these embodiments pertain having the 10 benefit of the teachings presented in the foregoing descriptions and the associated^ drawings. Therefore, it is to be understood that: the inventions are not to be 'limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be Included within the scope of the appended claims. Although specific terms are employed herein, they are used In a generic, and descriptive sense only and nqTfor |5i purposes of limitation.

The reference to any prior art in this specitication is not, and should not be taken as, an acknowledgement or any form Of suggestion that the prior art forms part of the common genera! knowledge in Australia. in this Specification, the terms "comprise’1, “comprises", 'Comprising" or similar 20 terms are intended to mean a non-exclusive inclusion, such that a system, method or apparatus that comprises a list of elements does not include those elements solely, but may well include other elements not listed*:

Claims (57)

1. A sonar transducer assembly, comprising: a plurality of transducer elements, each one of the plurality of transducer elements having a substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallel to a longitudinal length of the transducer element that is significantly less than a beamwidth of the sonar beam in a direction perpendicular to the longitudinal length of the transducer element, wherein the plurality of transducer elements are positioned such that the longitudinal lengths of at least two of the plurality of transducer elements are substantially parallel to each other, and wherein the plurality of transducer elements include at least: a first linear transducer element positioned within a housing to project sonar pulses from a first side of the housing in a direction substantially perpendicular to a centerline of the housing, a second linear transducer element positioned within the housing to lie substantially in a plane with the first linear transducer element and project sonar pulses from a second side of the housing that is generally opposite of the first side, and a third linear transducer element positioned within the housing to project sonar pulses in a direction substantially perpendicular to the plane.

2. The transducer assembly of claim 1, wherein the first linear transducer element is positioned to project sonar pulses defining a beamwidth having a center forming about a 30 degree angle with respect to the plane, and wherein the second linear transducer element is also positioned to project sonar pulses defining a beamwidth having a center forming about a 30 degree angle with respect to the plane.

3. The transducer assembly of claim 1, wherein at least one transducer within the transducer assembly is configured to operate at a selected one of at least two selectable operating frequencies.

4. The transducer assembly of claim 3, wherein the selectable operating frequencies include about 455 kHz and 800 kHz.

5. The transducer assembly of claim 1, wherein the beamwidth of each of the transducer elements is about 0.8 degrees by about 32 degrees or about 1.4 degrees by about 56 degrees.

6. The transducer assembly of claim 1, wherein beams produced by each of the first, second and third transducers do not overlap with each other.

7. The transducer assembly of claim 1, wherein the transducer assembly includes a housing mountable to a watercraft and wherein the plurality of transducer elements are positioned within the housing.

8. The transducer assembly of claim 7, wherein the watercraft operates on a surface of a body of water.

9. The transducer assembly of claim 7, wherein the watercraft is a submersible vehicle.

10. The transducer assembly of claim 1, wherein the transducer assembly is configured to communicate with a single transceiver.

11. The transducer assembly of claim 1, wherein a length of a rectangular face of each of the transducer elements is about 120 mm and a width of the rectangular face of each of the transducer elements is about 3 mm.

12. The transducer assembly of claim 1, wherein the beamwidth in the direction parallel to longitudinal length of the transducer elements is less than about five percent as large as the beamwidth of the sonar beam in the direction perpendicular to the longitudinal length of the transducer elements.

13. The transducer assembly of claim 1, wherein respective sonar beams produced by each of the first, second, and third linear transducer elements provide substantially continuous sonar coverage from one side of a vessel on which the housing is mounted to an opposite side of the vessel.

14. The transducer assembly of claim 1, wherein the plurality of transducer elements are positioned such that the longitudinal lengths of each of the plurality of transducer elements are substantially parallel to each other.

15. The transducer assembly of claim 1, wherein the housing is mountable to a vessel to generate sonar pulses defining a fan-shaped beam extending from one side of the vessel to an opposite side of the vessel.

16. The transducer assembly of claim 1, wherein the housing is mountable to a vessel to generate sonar pulses defining a fan-shaped beam extending from a forward end of the vessel to an aft end of the vessel.

17. The transducer assembly of claim 1, wherein the first, second, and third linear transducer elements are positioned side by side with respect to each other.

18. The transducer assembly of claim 1, wherein the first, second, and third linear transducer elements are positioned collinear with respect to each other.

19. The transducer assembly of claim 1, wherein the third linear transducer element is positioned substantially between the first and second transducer elements.

20. The transducer assembly of claim 1, wherein the housing has a streamlined shape.

21. The transducer assembly of claim 1, wherein the third linear transducer element generates signals representing depth data.

22. The transducer assembly of claim 1, wherein the third linear transducer element generates signals representing water column data.

23. The transducer assembly of claim 1 wherein the third linear transducer element generates signals representing bottom data.

24. The transducer assembly of claim 1 wherein the third linear transducer element generates signals representing two or more of depth data, water column data and bottom data.

25. The transducer assembly of claim 1 wherein the third linear transducer element generates signals representing data vertically below the third transducer element.

26. The transducer assembly of claim 1, wherein the plurality of transducer elements further comprises a circular transducer element producing a conical downscan beam.

27. The transducer assembly of claim 26, wherein the sonar pulses from the third linear transducer element and the sonar pulses from the circular transducer element insonify areas of the bottom that at least partially overlap.

28. The sonar system of claim 26, wherein the sonar signal returns from the circular transducer element and third linear downscan element provide generally simultaneous data.

29. The transducer assembly of claim 1, further comprising shielding proximate predetermined surfaces of at least one of the transducer elements to minimize signal interference.

30. The transducer assembly of claim 1, further comprising an omnidirectional bracket for adapting said transducer assembly for adjustable directional mounting.

31. The transducer assembly of claim 26, wherein the circular transducer element produces a conical beam from within the housing.

32. A sonar system comprising: a transducer assembly including a plurality of transducer elements each having a substantially rectangular shape configured to produce a sonar beam having a beamwidth in a direction parallel to a longitudinal length of the transducer element that is significantly less than a beamwidth of the sonar beam in a direction perpendicular to the longitudinal length of the transducer element, wherein the plurality of transducer elements are positioned such that the longitudinal lengths of at least two of the plurality of transducer elements are substantially parallel to each other, and wherein the plurality of transducer elements include at least: a first linear transducer element positioned within a housing to project sonar pulses from a first side of the housing in a direction substantially perpendicular to a centerline of the housing, a second linear transducer element positioned within the housing to lie substantially in a plane with the first linear transducer element and project sonar pulses from a second side of the housing that is substantially opposite of the first side, and a third linear transducer element positioned within the housing to project sonar pulses in a direction substantially perpendicular to the plane; and a sonar module configured to enable operable communication with the transducer assembly, the sonar module including: a sonar signal processor to process sonar return signals received via the transducer assembly, and a transceiver configured to provide communication between the transducer assembly and the sonar signal processor.

33. The sonar system of claim 32, wherein the sonar module further comprises an Ethernet hub in communication with the signal processor.

34. The sonar system of claim 32, wherein the sonar module is provided within a single housing.

35. The sonar system of claim 34, wherein the housing has a streamlined shape.

36. The sonar system of claim 32, further comprising at least one visual display presenting an image representing the processed sonar return signals.

37. The sonar system of claim 36, wherein the display and the sonar module are in the same housing.

38. The sonar system of claim 36, wherein at least one display of the plurality of displays is enabled to simultaneously provide different images representing different information from the processed sonar return signals.

39. The sonar system of claim 32, wherein the sonar module further comprises configuration settings defining a predefined set of display images that may be presented.

40. The sonar system of claim 32, wherein the first linear transducer element is positioned to project sonar pulses defining a beamwidth having a center forming about a 30 degree angle with respect to the plane, and wherein the second linear transducer element is also positioned to project sonar pulses defining a beamwidth having a center forming about a 30 degree angle with respect to the plane.

41. The sonar system of claim 32, wherein the transducer assembly is configured to operate at a selected one of at least two selectable operating frequencies.

42. The sonar system of claim 41, wherein the selectable operating frequencies include about 455 kHz and 800 kHz.

43. The sonar system of claim 32, wherein beams produced by each of the first, second and third linear transducers do not overlap with each other.

44. The sonar system of claim 32, wherein the transducer assembly includes the housing being mountable to a watercraft and wherein the plurality of transducer elements are positioned within the housing.

45. The sonar system of claim 32, wherein the housing is mountable to a vessel to generate sonar pulses defining a fan-shaped beam extending from one side of the vessel to an opposite side of the vessel.

46. The sonar system of claim 32, wherein the transceiver comprises a single transceiver configured to provide communication between the plurality of transducer elements of the transducer assembly and the sonar signal processor.

47. The sonar system of claim 32, wherein the sonar signal processor is configured to display images of sonar data in which images corresponding to data received via the first and second linear transducers provide data regarding bottom features over greater than about fifty percent of a display screen when displayed and images corresponding to data received via the third linear transducer provide data regarding bottom features over less than fifty percent of a display screen when displayed.

48. The sonar system of claim 32, wherein the sonar signal processor is configured to display images of sonar data corresponding to data received via the third linear transducer representing bottom data.

49. The sonar system of claim 32, wherein the sonar signal processor is configured to display images of sonar data corresponding to data received via the third linear transducer representing water column data.

50. The sonar system of claim 32, wherein the sonar signal processor is configured to display images of sonar data corresponding to data received via the third linear transducer representing depth data.

51. The sonar system of claim 32, wherein the sonar signal processor is configured to display images of sonar data corresponding to data received via the third linear transducer representing two or more of depth data, water column data and bottom data.

52. The sonar system of claim 32 wherein the sonar signal processor is configured to display images of sonar data corresponding to data received via the third transducer element representing data vertically below the third transducer.

53. The sonar system of claim 32 further comprising a circular transducer element producing a conical downscan beam.

54. The sonar system of claim 32 further comprising a circular transducer element producing a conical downscan beam from within the housing.

55. The sonar system of claim 53 wherein the sonar pulses from the third linear transducer element and the sonar pulses from the circular transducer element sonify areas of the bottom that at least partially overlap.

56. The sonar system of claim 53 wherein the sonar signal returns from the circular transducer element and third linear downscan element provide generally simultaneous data.

57. A sonar transducer assembly for imaging an underwater environment beneath a watercraft traveling on a surface of a body of water, the sonar transducer assembly comprising: a housing mountable to the watercraft; a linear downscan transducer element positioned within the housing, the linear downscan transducer element having a substantially rectangular shape configured to produce a fan-shaped sonar beam having a relatively narrow beamwidth in a direction parallel to a longitudinal length of the linear downscan transducer element and a relatively wide beamwidth in a direction perpendicular to the longitudinal length of the transducer element, the linear downscan transducer element being positioned with the longitudinal length thereof extending in a fore-to-aft direction of the housing, wherein the linear downscan transducer element is positioned within the housing to project fan-shaped sonar beams in a direction substantially perpendicular to a plane corresponding to the surface of the body of water, said sonar beams being repeatedly emitted so as to sequentially insonify different fan-shaped regions of the underwater environment as the watercraft travels; a first linear sidescan transducer element and a second linear sidescan transducer element positioned within the housing, each of the first and second linear sidescan transducer elements having a substantially rectangular shape configured to produce a fan-shaped sonar beam having a relatively narrow beamwidth in a direction parallel to a longitudinal length of the linear downscan transducer element and a relatively wide beamwidth in a direction perpendicular to the longitudinal length of the transducer element, and being oriented in the housing so as to insonify respective fan-shaped regions differing from the fan-shaped regions insonified by the linear downscan transducer element.