A high-resolution and light-weight impulse radar has been developed for short range detection of subsurface objects and interfaces. This radar can be used as a hand-held instrument or it can be mounted on a vehicle. The new radar is optimized for fairly short measuring distances (about 2 m) with good accuracy (few centimetres). Modern data processing and display technology has been used in order to reduce the power consumption and physical size of the instrument. The radar has proved to be very useful in ice thickness measurements. For safety reasons it is essential to measure continuous profiles of the ice thickness and to find the weak spots in order to avoid vehicles to sink through the ice. The impulse radar measures a continuous profile of ice thickness without any conventional methods, e.g. by drilling holes in ice and measuring the thickness with a scale stick.