Abstract: A target object detecting device including first and second transmission signal generators, a wave transmitting array, first and second switches, and a controller is disclosed. The first and second transmission signal generators generate first and second transmission signals, respectively. The wave transmitting array has a plurality of wave transmitting elements which convert the first and second transmission signals into transmission waves. The first switch supplies the first transmission signal to one of the wave transmitting elements. The second switch supplies the second transmission signal to one of the wave transmitting elements. The controller performs a control in which the first switch switches the wave transmitting element to which the first transmission signal is supplied, from an element n to an element n+1, and the second switch switches the wave transmitting element to which the second transmission signal is supplied, from an element m to an element m+1.

Abstract: The present disclosure provides a target object detection device. The target object detection device includes a first transmission signal generator, a first transmission array, a first switch, and a controller. The first transmission signal generator is configured to generate a first transmission signal. The first transmission array includes a plurality of first transmission elements configured to convert the first transmission signal into a transmission wave. The first switch is configured to supply the first transmission signal to one of the first transmission elements in the first transmission array. The controller is configured to control the first switch to switch the first transmission element to which the first transmission signal is supplied from a first element to a second element at a first timing.

Abstract: An underwater detection apparatus that includes a transmission transducer including a plurality of transmission elements to be fixed to a vessel, at least one of the plurality of transmission elements extending in an oblique direction relative to a fore-aft direction of the vessel in a state where the transmission transducer is fixed to the vessel; a reception transducer including a plurality of reception elements; processing circuitry that acquires an attitude information of the vessel; a transmission circuit that drives the plurality of transmission elements based on the attitude information to control the transmission transducer to transmit a transmission wave in a given direction relative to a water surface; and a reception circuit that obtains a reception signal from at least one of the plurality of reception elements based on a reflection wave of the transmission wave.

Abstract: An underwater sounding apparatus includes a transmitter section (3) for transmitting an acoustic signal in a specific direction underwater from a ship, a receiver section (4) for receiving an echo reflected from inside a fish school FS as a result of the aforementioned transmitted acoustic signal by means of a receiving beam, and a signal processing section (5) for processing signals picked up by the aforementioned receiving beam. The signal processing section (5) calculates fish quantity information about the aforementioned fish school FS by integrating equivalent input sound intensities obtained by the aforementioned receiving beam in specific three-dimensional directions.

Abstract: A trawl net (2) is attached to ends of warps (4) extending from a ship (6), such as a trawl boat, in the sternward direction, and a transponder (5) to transmit a response signal is attached to an upper part of a net mouth of the trawl net (2). The ship (6) forms a transmission beam TB of a detection signal by a transducer (1) at the bottom of the ship, and performs detection in the detection range. The transponder (5) receives the detection signal, and forms a transmission beam TPB of a frequency different from that. A detection image and a position display image of the transponder are superposed and displayed on a display of a scanning sonar or are displayed side by side.

Abstract: An acoustic transducer 1 has a first cylindrical portion 1A and a second hemispherical portion 1B on which a plurality of transducer elements 10a, 10b are arranged. The transducer elements on the cylindrical portion are arranged to have six nearest neighbors. The arrangement may be such that the six transducer elements surrounding a given element describe the vertices of a regular hexagon. The hexagons thus described may be aligned so that two of their sides are parallel to the axis of the cylinder. The elements on the hemispherical portion may be arranged so that some elements have five nearest neighbors and others have six (the neighboring elements describing, for example, the vertices of hexagons and pentagons respectively). An underwater sounding apparatus may be constructed using the transducer.

Abstract: An underwater sounding apparatus includes a transmitter section (3) for transmitting an acoustic signal in a specific direction underwater from a ship, a receiver section (4) for receiving an echo reflected from inside a fish school FS as a result of the aforementioned transmitted acoustic signal by means of a receiving beam, and a signal processing section (5) for processing signals picked up by the aforementioned receiving beam. The signal processing section (5) calculates fish quantity information about the aforementioned fish school FS by integrating equivalent input sound intensities obtained by the aforementioned receiving beam in specific three-dimensional directions.

Abstract: An underwater sounding apparatus includes a transducer transmitting an acoustic sounding beam along a plurality of directional surfaces that intersect in three-dimensions and receiving echoes returning from within a fish school using receiving beams. The transducer can form the receiving beams in directions generally along a substantially vertical planar directional surface and in directions generally along a substantially umbrella-shaped directional surface formed around the ship, the umbrella-shaped directional surface intersecting both a horizontal plane and the vertical, planar directional surface. A signal processing section calculates fish quantity information about the fish school by constructing pseudo-three-dimensional data from data obtained by the receiving beam. Also, the signal processing section may binarize the data obtained by the receiving beams and calculates an approximate value of the volume of the fish school by constructing pseudo-three-dimensional data from the binarized data.

Abstract: An ultrasonic apparatus is disclosed that includes a transducer having a plurality of transducer elements, a controller operatively connected to the transducer and driving the transducer elements to produce a first ultrasonic transmitting beam having a first frequency and a second ultrasonic transmitting beam having a second frequency; and a processor operatively connected to said transducer for forming and moving reception beams to receive echo signals and extracting frequency components corresponding to said first ultrasonic transmitting beam and said second ultrasonic transmitting beam.

Abstract: An ultrasonic transmitter generates a reference signal based on a clock signal of a specific frequency and a control signal made up of binary values 0 and 1 for controlling how the level (High or Low) of a carrier drive signal should change, and generates an analog signal constituting the carrier drive signal by pulse-duration-modulating the reference signal. Produced from the carrier drive signal, a driving pulse signal is shaped into a curved waveform having a gradually rising leading edge and a gradually falling trailing edge as the amplitude of the carrier drive signal is gradually increased and decreased based on the control signal.

Abstract: While keeping a propeller located in a negative direction of a y-axis turning, transmission of acoustic waves from vibrating elements of a transducer unit is interrupted. Reference signals “A” and “B” which are receiving beam signals having principal acoustic axes oriented in a propeller direction are generated from received signals obtained by “A” and “B” group vibrating elements, respectively. Next, adjustment factors used for removing propeller noise from received signals obtained by vibrating elements on positive and negative sides of an x-axis are calculated by performing arithmetic operation on time-series data on the received signals obtained by the positive and negative sides vibrating elements and on time-series data on the reference signals “A” and “B”, respectively.

Abstract: A trawl net (2) is attached to ends of warps (4) extending from a ship (6), such as a trawl boat, in the sternward direction, and a transponder (5) to transmit a response signal is attached to an upper part of a net mouth of the trawl net (2). The ship (6) forms a transmission beam TB of a detection signal by a transducer (1) at the bottom of the ship, and performs detection in the detection range. The transponder (5) receives the detection signal, and forms a transmission beam TPB of a frequency different from that. A detection image and a position display image of the transponder are superposed and displayed on a display of a scanning sonar or are displayed side by side.

Abstract: An acoustic transducer has an upper cylindrical portion and a lower hemispherical portion on which a plurality of transducer elements are arranged. The transducer elements on the cylindrical portion are arranged in such a way that six transducer elements adjacent to any one of the transducer elements are located at vertices of a regular hexagon and regular hexagons adjoining in a horizontal direction have sides which are oriented parallel to an axial direction (vertical direction) of the cylindrical portion.

Abstract: An underwater sounding apparatus includes a transducer transmitting an acoustic sounding beam along a plurality of directional surfaces that intersect in three-dimensions and receiving echoes returning from within a fish school using receiving beams. The transducer can form the receiving beams in directions generally along a substantially vertical planar directional surface and in directions generally along a substantially umbrella-shaped directional surface formed around the ship, the umbrella-shaped directional surface intersecting both a horizontal plane and the vertical, planar directional surface. A signal processing section calculates fish quantity information about the fish school by constructing pseudo-three-dimensional data from data obtained by the receiving beam. Also, the signal processing section may binarize the data obtained by the receiving beams and calculates an approximate value of the volume of the fish school by constructing pseudo-three-dimensional data from the binarized data.

Abstract: An ultrasonic apparatus is disclosed that includes a transducer having a plurality of transducer elements, a controller operatively connected to the transducer and driving the transducer elements to produce a first ultrasonic transmitting beam having a first frequency and a second ultrasonic transmitting beam having a second frequency; and a processor operatively connected to said transducer for forming and moving reception beams to receive echo signals and extracting frequency components corresponding to said first ultrasonic transmitting beam and said second ultrasonic transmitting beam.

Abstract: While keeping a propeller located in a negative direction of a y-axis turning, transmission of acoustic waves from vibrating elements of a transducer unit is interrupted. Reference signals “A” and “B” which are receiving beam signals having principal acoustic axes oriented in a propeller direction are generated from received signals obtained by “A” and “B” group vibrating elements, respectively. Next, adjustment factors used for removing propeller noise from received signals obtained by vibrating elements on positive and negative sides of an x-axis are calculated by performing arithmetic operation on time-series data on the received signals obtained by the positive and negative sides vibrating elements and on time-series data on the reference signals “A” and “B”, respectively.

Abstract: A receiving beam is formed using 60 elements arranged in a 90° sector area of a cylindrical receiving array. Receiving beam 0 is formed with elements 0-59 divided into two (front and rear) groups. Specifically, the elements 0-59 are divided into rear group 1 (elements 0-8, 51-59) and front group 2 (elements 9-50) in the beam direction, and the receiving beam is formed by using sample data obtained from the transducer elements 0-8, 51-59 of group 1 in a current scanning cycle as well as sample data obtained from the transducer elements 9-50 of group 2 in a preceding scanning cycle. This approach makes it possible to form the receiving beam such that incoming waves of a short-pulse signal would simultaneously hit the relevant transducer elements of the receiving array and thereby improve directivity and sensitivity of the receiving beam for the reception of short-pulse waves.

Abstract: A received beam-forming apparatus is disclosed is which echo signals received by multiple ultrasonic transducer elements arranged in a linear form are sampled at a specific scanning frequency to obtain sample data. A receiving beam-forming apparatus includes a memory which stores the sample data derived from multiple scanning cycles; and a beamformer which divides the multiple ultrasonic transducer elements into multiple blocks, reads out the sample data derived from different scanning cycles for the individual blocks from said memory, and forms a receiving beam in a specific direction using the individual sample data which have been read out. A sonar system using the receiving-beam forming apparatus is also disclosed as is a matched filter which selects an arc-shaped part of an ultrasonic transducer element array.

Abstract: An ultrasonic transmitter generates a reference signal based on a clock signal of a specific frequency and a control signal made up of binary values 0 and 1 for controlling how the level (High or Low) of a carrier drive signal should change, and generates an analog signal constituting the carrier drive signal by pulse-duration-modulating the reference signal. Produced from the carrier drive signal, a driving pulse signal is shaped into a curved waveform having a gradually rising leading edge and a gradually falling trailing edge as the amplitude of the carrier drive signal is gradually increased and decreased based on the control signal.

Abstract: The invention provides an ultrasonic transmit-receive apparatus which solves a false image problem caused by grating lobes and side lobes and offers high bearing resolution without increasing in the scale of hardware or in manufacturing cost. Using a transducer having multiple transducer elements arranged on a surface of the transducer along its circumferential direction, the apparatus emits ultrasonic waves in directionally varying frequency bands and receives echo signals from specified angular directions while selecting the frequency from one direction to another.