Yohei Ishikawa

2GHz band quadruple mode dielectric resonator filter for cellular base station

This paper describes a novel 2GHz bandpass filter using a novel quadruple mode dielectric resonator for compact cellular base station. We propose small high Q dielectric resonator technique using TM/sub 11//spl delta/-x, TM/sub 11//spl delta/-y, TE/sub 01//spl delta/-x and TE/sub 01//spl delta/-y modes. It has very high unloaded Q factor value of about 15000 at 2GHz band. We have designed and manufactured a 4-pole band filter using this resonator. Insertion loss is very low of less than 0.23 dB and high attenuation of 90dB. Outer dimensions are 48 /spl times/ 48 /spl times/ 42 mm.

Multi-beam automotive radar front end using non-contact cylindrical NRD switch

We have developed a multi-beam automotive FM-pulse radar font end for the 60 GHz band by using new NRD technologies. The multi-beam antenna consists of a dielectric lens and a non-contact cylindrical NRD switch with four dielectric resonator radiators and a motor. The millimeter-wave circuit consists of our original NRD guide components. The size of the equipment is W125 mm/spl times/H80 mm/spl times/D74 mm. This is expected to be applicable for automotive ICC applications.

Surface resistance of screen-printed Bi2223 thick films on Ag and dielectric ceramic substrates

Surface resistance R/sub s/ of screen-printed (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ thick films on Ag, MgO, and Ba(Sn,Mg,Ta)O/sub 3/ substrates was measured at 10.7 GHz in the temperature range between 20 and 130 K using a dielectric resonator method. For thick films on Ag substrates, it becomes lower than that for a Cu plate as temperature decreases below 100 K, and reaches 1.7 m/spl Omega/ at 77 K and 0.3 m/spl Omega/ at 30 K. The use of MgO or Ba(Sn,Mg,Ta)O/sub 3/ dielectric substrate for film fabrication causes some degradation in the value of R/sub s/, while still being superior to that for a Cu plate below 80 K. From a practical point of view, the (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ thick films were screen-printed on both sides of Ba(Sn,Mg,Ta)O/sub 3/ disk to serve as superconducting electrodes for the dielectric resonator. The unloaded quality factor Q/sub n/ for the resonator at 2.1 GHz on a TM/sub 010/ mode is superior to the same dielectric resonator with Cu electrodes below 90 K. It is 3 times higher than the value for the resonator with Cu electrodes at 70 K and also 5 times higher at 30 K.