The Invention of Ferrites and Their Contribution to the Miniaturization of Radios

  title={The Invention of Ferrites and Their Contribution to the Miniaturization of Radios},
  author={A. Okamoto},
  journal={2009 IEEE Globecom Workshops},
  • A. Okamoto
  • Published 2009
  • Computer Science
  • 2009 IEEE Globecom Workshops
Dr. Takeshi Takei, the professor at Tokyo Institute of Technology, discovered that oxides containing zinc and iron have distinguished magnetic properties. In 1930, Prof. Kato and Prof. Takei applied a patent for their discovery of oxide magnetic core materials, which was granted in 1932 in Japan. Tokyo Denki Kagaku Kogyo (now TDK Corporation) was founded in 1935 to commercialize this newly invented ferrite cores as a venture company originated from the university patent of ferrite TDK started… Expand
Morphological, Raman, electrical and dielectric properties of rare earth doped X-type hexagonal ferrites
Abstract The influence of rare-earth metals (La, Nd, Gd, Tb, Dy) on morphology, Raman, electrical and dielectric properties of Ba2NiCoRExFe28−xO46 ferrites were studied. The scanning electronExpand
Ferrite Materials and Applications
This chapter starts from a generalized permeability and aims at providing a better understanding of the ferrites behavior in the microwave fields. The formula of the generalized permeability explainsExpand
Modeling and Simulation of Thermomagnetic Materials for Thermally Actuated Magnetization Flux Pumping Method
The potential of bulk high-temperature superconductors to carry high current densities and trap significant magnetic fields at cryogenic temperatures makes them particularly attractive for a varietyExpand
High Technology Applications of Barium and Strontium Ferrite Magnets
Ceramic magnets as barium ferrite or strontium ferrite have many applications in high technology. One of the reasons is the low cost when compared to competitor materials, as Alnico, MnBi, MnAl orExpand
Progress and prospects of hard hexaferrites for permanent magnet applications
Permanent magnets based on hard hexaferrite represent the largest family of magnets being used today by volume. They generate moderate remanence induction, but present crucial advantages in terms ofExpand
Influence of Mg concentration on physico-chemical properties of Cd ferrites (CdMg1.5xFe2−xO4) synthesized by sol–gel combustion method
Abstract The nanofabrication, characterization, microstructural and magnetic properties of pure and Mg 2+ doped cadmium ferrite (CdFe 2 − x Mg 1.5 x O 4 ; x  = 0.0–0.7) have been carried out.Expand
Synthesis and Characterization of Cobalt Substituted NaZnFe2O4 by Sol-Gel Method
The samples of NaCo0.11Zn0.39Fe2O4 and NaCo0.24Zn0.26Fe2O4 were synthesized by sol-gel method. The structural characterizations of these samples were performed by X-ray diffraction (XRD), ScanningExpand
Magnetic augmented rotation system (MARS) - properties and performance
MAGNETIC AUGMENTED ROTATION SYSTEM (MARS) PROPERTIES AND PERFORMANCE by Ruolei Liu Magnetic Augmented Rotation System (MARS) is proposed as a system for conversion of mechanical energy intoExpand
Design and Characterization of Ferrite Magnetic Nanoparticle Modified Polymeric Composites
  • Zhong Hu, J. Kanagaraj, +4 authors P. Kharel
  • Materials Science, Computer Science
  • 2019 IEEE International Conference on Electro Information Technology (EIT)
  • 2019
The effective relative permittivity and permeability of the nanocomposites were predicted by numerical method, compared with the results of the analytical methods, and validated by the results from experiments. Expand


Intermediate Frequency Transformer with Magnetic Core ”
  • Radio Japan
  • 1940
Production method of magnetic core mainly made of metal oxides ” [ 5 ] “ Evaluation Report of Ferrite Cores for RF Inductor Application ”
  • Studies on Zinc Ferrite . Its Formation , Composition , and Chemical and Magnetic Properties ”
  • 1930
Studies on the Adoption of Intermediate Frequency Band - pass Filter with Replace Mechanism ”
  • Technical J . of Kokusai Denki Tsushin