So, instead of using ultrasound, radio waves are used as they travel at 300,000,000 m/s. It works in the same way as sonar but with radio waves in place of ultrasound. A short pulse of radio waves ...

Radio waves could allow robots or autonomous vehicles to see through thick smoke, intense rain – or even around corners. Such waves can even detect concealed weapons. But simulating visual ...

THE modified form of the ionic deflexion theory of wave propagation, discussed by Messrs. Nichols and Schelling (NATURE, March 7, vol. 115, p. 334), appears to have been suggested in England and ...