Radar(Radio Detection And Ranging) is an object detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. Now, the radar is rotating 180 degrees and calculating the distance away from the ultrasonic sensor. It is sending the data (angle and distance) to the computer using serial port. Processing application is converting the polar to rectangular coordinates and showing them on screen. Ultrasonic system is the most useful and widely used system in the RADAR communication, and the object detector as well as it mostly used in SONAR system. (i.e. to measure the depth of sea) It is wireless technology and the wave are used in the communication are not hazardous to human being. In this project we deal with the issues of pertain to the subject such as object detection distance measurement. Here we present the ultrasonic radar system which is very useful in object detection as well as distance measurement.