Naohisa Uehara

FMCW automotive radars using only in-phase channel

This paper describes a novel Frequency Modulated Continuous Wave (FMCW) radar that is used only with in-phase channel. The merit of using the radar in this fashion is that it can suppress the ambiguity about range and target velocity, thus reducing performance deterioration. The radar is used in detection applications.

A high-gain 50-GHz-band monolithic balanced gate mixer with an external IF balun

This paper presents a 50 GHz-band high gain monolithic balanced gate mixer. Conversion gain of the mixer is improved by using an external IF balun with high impedance transforming ratio. This paper shows that the IF impedance of the balanced gate mixer can be approximated from a small signal equivalent circuit. The maximum conversion gain of 8.2 dB is achieved at a LO power of 0 dBm. The effectiveness of the described mixer is confirmed experimentally.

High Efficiency Isolated AC-DC Converter with Gradationally Controlled Voltage Inverter for On-Board Charger

We have developed a new isolated AC/DC converter for electric vehicle on-board chargers. It consists of an AC/DC converter with Gradationally Controlled Voltage Inverter (GCVI AC/DC converter) and an isolated Zero-Voltage-Switching (ZVS) DC/DC converter, each of which is optimally controlled to convert in a highly efficient means. As a result, the new on-board charger has achieved a power conversion efficiency of over 94%.

A Millimeter-Wave Pulse Transmitter with a Harmonic Mixer

Emulsions of oil and water are broken by contacting the emulsions with a quaternized polyalkylene polyamine, e.g., the adduct of 2-hydroxy-3-chloropropyl trimethyl ammonium chloride and a polyethylene polyamine.