| 摘要 |
A sensor is provided for measuring the speed of a moving sports object, particularly an object being shot or launched, for example, from a gun, bow or other implement, such as a bullet or paint ball being shot from a gun or an arrow being shot from a bow. The sensor is operable over a short range and is preferably mounted in close proximity to the path of the moving object. The sensor of the preferred embodiment utilizes CW Doppler radar in the form of a microwave radio frequency transmitter and receiver that has a single-transistor integrated antenna/oscillator. A simple, low cost unit having a low radiation and low energy consumption transmitter, receiver and signal processor, is provided. In use, the unit is situated so as to place a transmit/receive antenna close to or in the line of motion of the object. Such an antenna, so positioned, may be separated from the unit and connected through a transmission line. The remote display/annunciator can also or in the alternative be separated and located remote from the transmitter/receiver and connected by a cable or a wireless link. Paint ball gun marker velocity or bullet velocity can be measured or the gun calibrated with a sensor antenna on the gun barrel, and archery arrow velocity can be measured or calibrated with a sensor fixed to a bow. |
