24 GHz RFID transponder frontend with an equal gain baseband combining for industry 4.0 applications

A receiver system with an equal gain baseband combining for a sensor tag integrated in a rotating machine tool holder and operating in the 24 GHz industrial, scientific and medical band (ISM) is presented. The sensor has an easy to customize diversity receiver which guarantees a stable wireless data transfer at each position of the rotating machine tool holder, even when a non omnidirectional antenna is used. An overview is given of the operational environment for an example Industry 4.0 application, of the construction and functionality of the sensor tag and of the equal gain baseband combining, which is used to combine multiple receivers. The performance of the new receiver system is evaluated and compared to a single receiver system.