Cars-trains absolute speed measurement system has a mobile unit moving parallel to the ground and having a Doppler radar with a transmitter and receiver

摘要

The absolute speed measurement unit (1) has a mobile unit moving parallel to the ground (33) and having a Doppler radar with a transmitter (21) and receiver (22). The returned signal is detected and multiplied with the control signal. Filtering (17) is carried out, providing a low and high frequency. The process is repeated for a second time period, and two frequencies corresponding to the reflecting obstacle at different positions found. The speed of the mobile unit at the two time periods is calculated, resolving two equations with unknowns. An Independent claim is also included for the device.