Shinichi Ohtsu

Analysis of radiation caused by LSI package cross talk and cable by using the time-domain moment method

We have developed the direct time-domain moment method, which is applicable to arbitrarily shaped models made of conductors and dielectrics. Using the method, we have analyzed the cross talk phenomenon within a LSI package. We have shown that, in the PCB with the LSI and a cable, the noise induced by the cross talk causes the strong radiation through the cable. Still more we have shown a remedy for the cross talk by simulations.

Noise simulation of hard disk drive by using moment method

Noise, which is generated in a read amp of a hard disk drive (HDD), is analyzed by using the moment method. The noise source is assumed to be a near-by interface cable. From the results of the analysis, the methods used to decrease the noise are shown to be effective. In addition, it is shown that the noise is affected by the grounding method between signal ground (SG) and frame ground (FG).

Analysis of correction factor for site attenuation

NSA and its correction factors are analyzed theoretically and simulated by the moment method using a model of the improved biconical antenna that has no abnormal resonance phenomena, NSA and its correction factors. The results show that 3 kinds of correction factor were necessary for a good agreement between simulated NSA values and the CISPR standard value

Radiation from multilayer microstrip lines using surface formulation

Finite multilayer microstrip lines including vias are analyzed by using the piecewise sinusoidal reaction matching moment method (PWSMM) and the surface formulation. To deal with conductors, such as vias, which connect conductors in different materials, a new supplementary boundary condition is tried. An approximation to calculate quickly the mutual impedance matrix between equivalent surface currents in the spectrum analysis is also tried. The results have been in good agreement with the data calculated by using the transmission line theory.