Implementation of DPSK-based Obstacle Detection System using UItrasound for Vehicles

When an obstacle is detected by using an ultrasonic sensor, a signal other than that transmitted by the other ultrasonic sensor may act as an interference signal. Therefore, it is possible to distinguish the signal by inserting the ID into the ultrasonic signal and mainly use the DSSS. However, since the bandwidth of the ultrasonic sensor is very narrow, the data rate is very low when data is transmitted, which makes it difficult to detect a near obstacle due to a long transmission time. Therefore, the detection interval, the modulation method and the code length are biased so as to detect both near and far obstacles. Experiments were conducted using DBPSK and FDM at near and DQPSK at far distance, and it was confirmed that signal detection was possible by the correlation peak of the signal.