Furuno Electric Company Limited

The University of Tokyo

Akira Okunishi

Yasushi Nishimori

Koji Dai

Hiroshi Iino

Minoru Handa

Sae Takemoto

Koji Nishiyama

Hitoshi Maeno

Yasunobu Asada

Kazuya Nakagawa

Masahiro Nakahama

Takeharu Yamaguchi

Nicolas Borrallo

Masashi Ohhora

Kouzo Tokuyama

Yasuo Ito

Teruhisa Komatsu

Koji Yokuda

A detection device detects a target based on a reception signal obtained from a reflection signal of a transmission signal. The detection device includes a Doppler frequency component generator that acquires a Doppler frequency component that indicates the amplitude level of a reception signal, for at least one Doppler frequency, based on the reception signal, a region identifier that identifies a first region and a second region that is outside the first region, based on the value of the amplitude level and the increase rate in the amplitude level, a second-Doppler frequency component suppressor that suppresses the Doppler frequency component of an unnecessary signal, out of the Doppler frequency component corresponding to the second region, and a combiner that combines the Doppler frequency component corresponding to the first region outputted from the region identifier, and the output of the second Doppler frequency component suppressor.

Detection device, radar device, detection method, and detection program

A radar apparatus using a pulse pair method to quickly measure a relative speed of an object. The radar apparatus includes: A data acquirer that acquires data relating to a pulse width, a repetition frequency, and a highest staggered ratio; A staggered pattern output unit that outputs a specific staggered pattern in which a total of phase changes within a sweep range of the target of the pulse pairing can be approximated to zero, wherein each phase change is caused by the pulse pairing on a target object at a constant speed due to a difference between an average transmission interval and a transmission interval between transmissions within the sweep range; And a setter that sets the transmission interval of a pulse signal by using the pulse width, the repetition frequency, the highest staggered ratio, and the specific staggered pattern.

Pulse signal setting device, radar apparatus, method and program of setting pulse signal

A signal processing device is provided. The device includes an echo signal input unit for receiving echo signals resulted from transmission signals reflected on an object. The transmission signals are transmitted from a transmission source at transmission timings at predetermined time intervals, at least one of the transmission timings shifted from the other timings in time. The device includes a complex reception signal generator for generating complex reception signals, a phase calculator for calculating a phase change amount of the complex reception signals with respect to a reference phase, a phase corrector for phase-correcting the complex reception signals and outputting the corrected signals, and a Doppler processor for performing Doppler processing on the corrected signals and outputting the Doppler-processed signals as Doppler echo signals of the object.

Signal processing device, radar apparatus, target object method

A target object detection device is provided. The device includes an antenna unit for transmitting a detection signal in an observing direction at a predetermined detection cycle and receiving a reflection signal of the detection signal, a receiver for outputting reception data obtained by sampling the reception signal that is received by the antenna unit, a detection data generator for outputting detection data obtained by correlating current reception data with previous detection data, and a detection cycle adjuster for adjusting the detection cycle based on the detection data.

Target object detection device, target object detecting method, computer readable media storing target object detecting program, and radar apparatus

A radar device is provided in this disclosure. The radar device includes an area determination module for performing a determination of a noise superior area or a target-echo superior area for each divided area of a radar-search area defined in advance, a noise-level calculation module for calculating a noise level for a divided area based on received signals from the divided area that is determined as the noise superior area, and an interpolation module for interpolating or extrapolating the calculated noise level for the divided area that is determined as the noise superior area, to obtain a noise level for a divided area that is determined as the target-echo superior area.

Radar device

A device and method for determining bottom sediment is provided. The method includes transmitting a pulse of a pulse width corresponding to a water-bottom depth, extracting a series of amplitude data of water-bottom echo signals from predetermined signals among the water-bottom echo signals received by the transducer at a predetermined time interval, normalizing the extracted series of amplitude data after TVG-processed, calculating two or more feature quantities based on the normalized series of amplitude data in each of segments of the normalized series of amplitude data, and a value corresponding to the water-bottom depth, and generating bottom-sediment classification information indicating the bottom sediment based on the two or more feature quantities.

Bottom-sediment classification device and method

A trawl net () is attached to ends of warps () extending from a ship (), such as a trawl boat, in the sternward direction, and a transponder () to transmit a response signal is attached to an upper part of a net mouth of the trawl net (). The ship () forms a transmission beam TB of a detection signal by a transducer () at the bottom of the ship, and performs detection in the detection range. The transponder () 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.

Ultrasonic wave transmitting and receiving system for detecting underwater objects

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 &#x201c;A&#x201d; and &#x201c;B&#x201d; 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 &#x201c;A&#x201d; and &#x201c;B&#x201d;, respectively. When performing underwater sounding operation by transmitting acoustic waves, a product of the reference signal &#x201c;A&#x201d; or &#x201c;B&#x201d; and the adjustment factor is subtracted from the received signal obtained by each of the positive and negative sides vibrating elements, respectively.

Underwater sounding apparatus

A receiving beam is formed using 60 elements arranged in a 90&#xb0; sector area of a cylindrical receiving array. Receiving beamis formed with elementsdivided into two (front and rear) groups. Specifically, the elementsare divided into rear group 1 (elements) and front group 2 (elements) in the beam direction, and the receiving beam is formed by using sample data obtained from the transducer elementsof group 1 in a current scanning cycle as well as sample data obtained from the transducer elementsof 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.

Method and apparatus for forming a reception beam

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.

Growing community of inventors

Nishinomiya, Japan

Akira Okunishi