Study of a Ferrite LTCC Multifunctional Circulator With Integrated Winding

摘要: This paper shows a study of new ferrite low-temperature cofired ceramic (LTCC) circulator with integrated winding. The external magnets used in traditional circulators must be strong to overcome the ferrite’s demagnetization factor. novel presented herein uses an embedded winding within magnetize material from inside, thereby significantly reducing effects. Because controllability bias field, resulting device is also multifunctional: when windings are energized by current, operates as dynamic which circulation direction can changed switching current. If magnet placed on circulator, its operating frequency adjusting Unlike other LTCC magnets, proposed even operate power splitter removing A prototype has been characterized three states: unbiased, biased windings, and magnets. When no current applied, transmission each port about −5 dB return loss better than 20 at 14.8 GHz. 300 mA injected into measured insertion isolation approximately 3 8 dB, respectively, whereas 14.2 added addition 200 mA, improve 1.6 23 variation circulator’s working 0.6 achieved first change internal magnetization $\boldsymbol {M}$ less 120 then heat due increases $\mu _{\textrm {eff}}$ , leading more shifting. total size ( $L \times W H$ ) $8~\textrm {mm} 8~\textrm 1.1$ mm.