Summary
International Symposium on Antennas and Propagation
2009
Session Number:1E1
Session:
Number:1E1-4
Three-strip ferrite circulator design based on Coupled Mode Method
Wojciech Marynowski, Jerzy Mazur,
pp.205-208
Publication Date:2009/10/21
Online ISSN:2188-5079
Summary:
Nowadays, microwave integrated systems include nonreciprocal structures such as circulators, isolators, phase shifters, operating over a broad frequency band. Recently, axially magnetized microstrip or slot ferrite coupled line sections have been developed and employed to realize integrated nonreciprocal devices [1?4]. The advantage of this class of the devices is a weak magnetic field required for Faraday’s effect [5] defining their nonreciprocal operation. The potential drawbacks of these structures are high insertion losses associated with a ferrite slab, which is often several wavelengths long. Recent research of the ferrite coupled line devices is focused on improvement of their parameters such as insertion losses and isolation. These devices are realized in finline [1], slotline [2] or microstrip [3] technology. Also, the investigations aimed at searching for new structures of ferrite coupled lines are conducted [4]. In this paper a new configuration of the ferrite coupled line section consisting of three strips is presented. The coupled mode method was used to determine the propagation coefficients in the ferrite section. To evaluate scattering matrix of the ferrite coupled line junction the mode matching method was utilized. With the use of the S-matrix the performance of the circulator was predicted and verified via experiment. A good agreement between simulation end measurement was achieved.