Development of AVR microcontroller-based antenna measurement tool for student experimentation

A development of antenna measurement tool for student experimentation is proposed based on AVR microcontroller as main controller unit (MCU). The system of antenna measurement tool is expected to be low-cost and easy-to-use to overcome the problem in cost and complexity of the commercial tool. The proposed system which uses an AVR ATMega8535 as an MCU controls the position of antenna under test (AUT) in spherical coordinate using elevation-over-azimuth configuration. Mechanically, the system is implemented by stepper motor, gear system and a turntable for positioning the AUT on azimuth and elevation angle. The user interface of system is realized by a keypad and LCD display. From the result, it shows that the realized antenna measurement tool can handle a patch antenna of 50gram weight with the deviation angle of 1°. Meanwhile for a patch antenna of 100gram weight, the deviation angle increases to be 2.5°. In addition, due to the torque of antenna, the deviation on elevation angle becomes larger for the elevation angle closer to 180°.