A speed sensor which aligns a normal direction of one patch antenna which is disposed on a mounted board, and an optical axis of a dielectric lens uses a frame for inclining a sensor module, in order to obtain a component cos θ in a traveling direction when the speed sensor is installed on a horizontally vertical surface of an automobile or a railway car. When beams are condensed by using the one patch antenna and the cannonball-shaped dielectric lens, the dielectric lens is inclined and a bottom surface portion of the lens is cut with a plane parallel with a surface of the antenna-mounted board. The one patch antenna is configured by one patch and a GND electrode and the gain center of radiation characteristics is a normal direction of the antenna board. However, the radiation characteristics have a substantially hemisphere surface wave shape.