Kuniaki Yoshitomi

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A sample and eficaent approach for the groove waveguzde usang the Fourzer transform tech-naque. The enforcement of the boundary condatzons at the groove apertures yaelds the samultaneous equations for the expand coeficzents of the electrac field on the groove aperture. Because the expand functzons sat-zsfy the the the edge condataon, the accurate solutaons(More)
In this paper, a highly compact symmetrical planar ultra-wideband (UWB) antenna with dual band-notched at the bands of the wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) is presented. The size of the antenna is strictly miniaturized both physically and electrically. The band notching of WLAN and WiMAX is(More)
Extremely low frequency (ELF) magnetic fields (MFs) were measured at 696 points in a room of a Japanese apartment building. The building had 124 rooms with layouts and wiring identical to those of the studied room. ELF-MFs exceeded 0.4 microT in 24% of the living space, and the maximum value, 1.8 microT, was detected at floor level. Analysis of the MF(More)
In this paper, a novel compact filter-antenna with tunable frequency band is proposed and developed for interweave cognitive radio (CR) system. The antenna is fed by a microstrip line integrated with a ring resonator bandpass filter. Reconfiguration is achieved by centrally loading the ring resonator with only a single varactor diode. Furthermore, the(More)
– This paper presents a novel design of a 2 × 2 slot dipole array antenna with the reflector fed by coplanar waveguide (CPW). The proposed antenna has four antenna elements and branched CPW structure to achieve a high antenna gain and a sharp beam. We fabricated and measured the array antenna with the reflector. The measured forward directional peak gain(More)
This paper presents the design of the circularly polarized slot antenna on the flexible substrate for ultra wide band (UWB) high band application. We applied two slots which are crossed perpendicularly to obtain circularly polarized wave. By optimizing the lengths and widths of the antenna slots and substrate, wide band impedance matching can be realized.(More)