Detection method for direction of motion using doppler speedometer - involves part of transmitter frequency mixed with reflected signal and use of flip flop for tripping

摘要

The transmitter frequency is mixed with the reflected signal in a microwave diode. An additional mixing is carried out in a second microwave diode, with the phase of one of the two signals shifted by 90 deg. so that outputs of this Doppler speedometer deliver two signals whose phases also differ. These signals are applied to a flip flop each (ST1, ST2) whose tripping levels are the same. Sequence in time of tripping points (M, B, K, L) of both flip flops is detected. The sequence is characteristic for the object direction of motion.