Microstrip‐line‐based K‐band isolator and Ku‐band phase shifter with barium hexa ferrite disc

Abstract

AbstractThis article deals with the operational behavior of barium hexaferrite (BHF) disc when incorporated in microwave substrates for wireless applications. A microstrip line printed on a Rogers substrate (35 mm × 35 mm × 1.6 mm) has been used in the design to observe the effect of BHF material. A BHF circular‐shaped disc of radius 4.5 mm and thickness 1 mm is inserted in the middle of the microstrip line. The ferrite is biased using miniature lightweight neodymium magnets stacked one over the other to obtain desired magnetic field strength. The proposed microstrip line inserted with a BHF disc exhibits wide band isolation properties in the K‐band (15–21 GHz) with an average isolation of 20 dB and peak isolation of 51 dB centered at 18.5 GHz. It is observed that the same circuit is behaving as a phase shifter showing a 45° ± 3° phase shift in the band ranging from 12 to 14 GHz. The proposed compact microstrip‐line circuit can be used as both ferrite phase shifter and isolator in consecutive bands (Ku‐ and K‐bands) with ease of integration and biasing.