According to the above method, depending on a combination of transmission elements for ultrasonic wave transmission, it is possible to change {HEAD ~ the detection area} of {TAIL ~ the ultrasonic wave} 
of
According to the above method , depending on a combination of transmission elements for ultrasonic wave transmission , it is possible to change { HEAD ~ the detection area } of { TAIL ~ the ultrasonic wave }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL