Yasutake Hirachi

A Wireless Video Home-link Using 60GHz Band: Concept and Performance of the Developed System

A concept and requirements of a millimeter-wave video transmission system as a wireless home-link using 60-GHz band are described. This system can transmit broadcast television (TV) signals from TV antennas to TV set and thus can be regarded as a substitute for a feeder line. The feasibility study by investigating the systems CNR and SNR performances using MMIC-based experimental setup is also described.

Status of millimeter-wave MMIC's and their applications in Japan

A 50 nm-gate lattice-matched InAlAs/InGaAs HEMT with the cutoff frequency of 362 GHz was developed. A K-band power amplifier module achieved the output power of 33.5 dBm at 24 GHz. A miniature and broadband p-HEMT LNA MMIC exhibited the gain of 14.5 dB and the noise figure of 1.7 dB at 26 GHz. A set of 76 GHz fully MMIC chips based on the 0.15 ¿m-gate p-HEMT process was developed for the car radar systems. Low-price, small-size and easily usable 60 GHz modules are expected by mm-wave home-link use.

HEMT's and New Devices for High-Speed Applications

This paper describes the state of the art in the research and development of HEMTs and new devices for microwave-frequency and high-speed applications in Japan. Low-noise HEMTs have already been commercial available, and are successfully utilized in the application such as satellite-communications and radio astronomy. A 4.1K HEMT gate array was fabricated, which was the largest scale HEMT logic LSI. This gate array realized a 16 × 16 bit parallel multiplier which exhibited the multiplication-time of 4.1 ns at 300 K. A new functional, resonant-tunneling hot electron transistor (RHET) was demonstrated, which enables us to build an Exclusive-NOR gate using only one transistor. A HBT with a modified collector structure in which electron transport can mostly be confined to ¿-valley of GaAs was developed, and the HBT achieved the maximum fT as high as 105 GHz at a collector current density in the mid 104 A/cm2.