Rotary Coupler in Microstrip Line Design for Data Transmission in the 2.45GHz ISM Band

In this paper a rotary coupler is presented that can be used for signal transmission on fast rotating shafts. Rotary couplers may be necessary especially in big industrial halls where, due to more and more transmitters around 2.45GHz, the industrial, scientific and medical (ISM) band of many radio standards, the channel can be too crowded to reliably transfer safety critical information. The concept of the presented coupler is a low-cost and splitable design in order to be attached around a shaft even without the disassembly of the entire machinery.