The present invention is a method of and system for imaging an object with an ultrasound transducer array that transmits ultrasound beams and detects echoes reflected from the object. In the X-ray tube, electrons emitted from an electron gun are made to collide with an X-ray target, and X-rays generated at the X-ray target due to the collision are taken out to an exterior. Actual communication itself is preceded by coherent channel measurement of a transmission channel by using the training section to specify a length of the short code to be a measurement period and using N cycles of a carrier as a time resolution for measurement.