Hideki Asao

A broadband dielectric diplexer using a snaked strip-line

A diplexer composed of a snaked stripline low-pass filter and a dielectric bandpass filter was developed. The sharper cutoff characteristics of the low-pass filter permit reduction of the element number. In addition, the filters are miniaturized by the use of a high-permittivity dielectric. A 1 GHz-band diplexer with dimensions of 12 mm*50 mm*50 mm was fabricated. This diplexer is suitable for satellite communications.<<ETX>>

Metal-plated plastic waveguide filter using injection molding process

A metal-plated plastic waveguide filter for Ka-band wireless Internet access systems is presented. As the filter is made using a plastic injection-molding process, the influence of indispensable draft angle on the waveguide walls was precisely considered in the design. By merging this design technique with the high-accuracy molding technique, no electrical tuning was necessary. It also realized the mass-productivity and cost reduction of Ka-band waveguide components.

Ku-band power combiner composed of metal-plated plastic waveguide hybrid

This paper describes the feasibility study of a metal-plated plastic waveguide power combiner for Ku-band solid state amplifier, aiming at the reduction in cost for high volume production and/or in weight. The relation between the draft angle for molding process and the combining loss characteristics is theoretically clarified. Furthermore, the experimental result of the 40 W four-way power combiner using plastic waveguide hybrid parts demonstrates validity of this investigation.

A Ku-band 40W high efficiency solid-state power amplifier

A Ku-band 40W high efficiency solid-state power amplifier (SSPA) has been developed. In order to achieve high efficiency, a Ku-band high efficiency internal-matched HFET and a small size and a low loss wave-guide combiner are developed and employed. The developed HFET achieves a power-added efficiency (PAE) of 37.5% and P1dB of 41.8dBm at base temperature (Tb) of 40degC. The source and load impedance of the HFET are matched to the optimum impedances for high temperature. The developed HFET achieves PAE of 33.8% and P1dB of 41.1 dBm over temperature range from -15 to 100 degC. The developed wave-guide combiner achieves insertion loss of less than 0.1dB. A Ku-band SSPA has been developed by using these components. It achieves an output power of 47.3 dBm (53.7W) and PAE of 25.6% at 14.2GHz and Tb of 25 degC, and achieves an output power of 46.4 dBm (43.6W), PAE of more than 21.9% and a linear gain of 36 dB at 14.0-14.4GHz over the temperature range from -15 to 95degC.