What is the most common type of antenna position indicating device used in modern RADARs?

The most common type of antenna position indicating device used in modern RADARs is resolvers. Resolvers are electromechanical devices that can accurately measure angular position and provide feedback on the angular positioning of an antenna. They work by converting the angular position into an electrical signal, which then can be processed to determine the exact orientation of the antenna.

Resolvers are highly valued in RADAR applications due to their precision and reliability. Their ability to operate without friction and their resistance to environmental factors, such as temperature and humidity, further enhance their utility in dynamic and challenging conditions typically encountered in RADAR systems.

In contrast, servo systems are more generalized control mechanisms that can include various types of feedback devices, while synchro transmitters are older technology that may not offer the same level of accuracy or integration in modern systems. Step motors are typically used for precise movements in mechanical systems but do not provide the continuous, real-time angular position feedback that resolvers offer, making them less suitable for the demands of RADAR applications.