Ultrasonic detecting device and ultrasonic detecting method

An ultrasonic detecting device for detecting target object within a given detection range, the device comprising:

• a transmitter configured to transmit a plurality of sequences, each sequence of the plurality of sequences including a first pulse wave in a first frequency band and a second pulse wave in a second frequency band, the second frequency band being a different frequency band from the first frequency band, a time interval between the first pulse wave and the second pulse wave being shorter than a time for ultrasound in water to make a round trip to the detection range, and the time interval being different in two sequences of the plurality of sequences;
• a receiver comprising a receiving element that receives a reflection wave of the first pulse wave and the second pulse wave, and that converts the reflection wave into an echo signal;
• and
• processing circuitry configured to:
• retrieve a first echo signal and a second echo signal from the echo signal, the first echo signal being retrieved from a frequency band corresponding to the first frequency band and the second echo signal being retrieved from a frequency band corresponding to the second frequency band, and
• generate a first image data and a second image data, the first image data being generated based on the first echo signal, the second image data being generated based on the second echo signal.

An ultrasonic detecting method for detecting target object within a given detection range, the method comprising:

• transmitting a first sequence including a first pulse wave in a first frequency band and a second pulse wave in a second frequency band, the second frequency band being a different frequency band from the first frequency band, a time interval between the first pulse wave and the second pulse wave being set to a first time interval, the first time interval being shorter than a time for ultrasound in water to make a round trip to the detection range;
• receiving a reflection wave of the first pulse wave and the second pulse wave with each receiving element of a plurality of receiving elements and converting the reflection wave of each receiving element into an echo signal;
• rotating at least a receiver comprising the plurality of receiving elements;
• retrieving a first echo signal and a second echo signal from the echo signal, the first echo signal being retrieved from a frequency band corresponding to the first frequency band and the second echo signal being retrieved from a frequency band corresponding to the second frequency band;
• generating a first image data and a second image data, the first image data being generated by performing a beamforming based on each first echo signal retrieved from the plurality of receiving elements, the second image data being generated by performing a beamforming based on each second echo signal retrieved from the plurality of receiving elements;
• generating a synthesized image data by synthesizing the first image data and the second image data based on an angular position of the receiver when the first image data is generated and an angular position of the receiver when the second image data is generated;
• and
• transmitting a second sequence after transmitting the first sequence, the second sequence including a third pulse wave in a third frequency band and a fourth pulse wave in a fourth frequency band, the fourth frequency band being a different frequency band from the third frequency band, a time interval between the third pulse wave and the fourth pulse wave being set to a second time interval, the second time interval being shorter than a time for ultrasound in water to make a round trip to the detection range, the second time interval being different from the first time interval.