Antenna directional pattern measurement system using AT89C52

An automatic directional pattern measurement system using microcontroller AT89C52, ADC0804A and LCD has been designed. The azimuth positioning system is developed using stepper motor with spur type of gear. Motor driver is designed by using transistors (BC548 and TIP122) and optocoupler (4N35). A detector diode MA4056(N) is used for signal detection. Its current output is coupled to voltage converter circuit developed around operational amplifier OP07E. The system operates in two modes reading-loading and reading-display mode. The System is tested for pyramidal horn antenna in the far field region in open area. The developed system is simple, low cost and user friendly.