Hiroya Sato

60GHz ultra compact transmitter/receiver with a low phase noise PLL-oscillator

In this paper, we present a transmitter and a receiver for a millimeter-wave video transmission system. The size of each is 110 mm/spl times/55 mm/spl times/23 mm, as a result of using an antenna-integrated millimeter-wave module and a filter-integrated SHP (sub-harmonically pumped) mixer MMIC. Both transmitter and receiver have a local signal of 29.5 GHz, for up/down-conversion, which is generated by multiplying a signal from a 1.8 GHz PLL-oscillator. A low phase noise of -103 dBc/Hz at 100 kHz offset was achieved.

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.

A 3.5 W HBT MMIC power amplifier module for mobile communications

A 900 MHz-band GaAs/GaAlAs HBT MMIC power amplifier module has been developed for mobile communications by using a novel assembly technique called BHS and an AlN package as the MMIC chip carrier. The power module gave a peak output power of 3.7 W and a power-added efficiency of 54.5% with a +6 V single supply voltage.<<ETX>>

Bump heat sink technology - A novel assembly technology suitable for power HBTs

A novel assembly technique, bump heat sink (BHS), suitable for compound semiconductor power HBTs is proposed and demonstrated. In this technique, the heat generated in the transistor junction is effectively conducted away through a gold bump which is located on the top of each transistor unit. Using this technique, power transistors are demonstrated with power added efficiencies /spl eta//sub add/ of 74%, 66% and 61% for 5.0 W, 8.0 W and 10.0 W output CW, respectively, at 0.9 GHz with V/sub cc/=6 V. A three-stage HBT MMIC power amplifier for GSM class 4 is also demonstrated with /spl eta//sub add/ >55% at V/sub cc/=4 V CW operation.<<ETX>>

A 5 GHz high efficiency and low distortion InGaP/GaAs HBT power amplifier MMIC

An InGaP/GaAs two-stage HBT power amplifier for 5 GHz Wireless-LAN applications was developed. By using a self-aligned base contact formation process and an external base region side etching process, a high gain HBT was realized. A small-sized via hole fabrication process was developed. The gain of multi-finger HBT was improved by locating via holes between each finger. Linearity was also improved by developing a new variable negative feedback circuit. A power amplifier MMIC utilizing this technology was fabricated, and 19.7 dBm output power, 22 dB gain, 22.5% power-added-efficiency (PAE), 5.0% error vector magnitude (EVM) were obtained at 54 Mbps transmission under a supply voltage of 3.3 V. These state of the art data represent the highest PAE reported for a the power amplifier MMIC in the 5 GHz Wireless-LAN application.

Thermal stabilization of AlGaAsGaAs power HBTs using n-AlxGa1−xAs emitter ballast resistors with high thermal coefficient of resistance

Abstract The use of n -Al x Ga 1− x As an emitter ballast layer material for AlGaAs GaAs heterojunction bipolar transistors (HBTs) is proposed and demonstrated. A high thermal coefficient of resistance can be obtained owing to the temperature dependence of the relative populations of the conduction band Γ, L and X valleys if the Al mole fraction x of the n -Al x Ga 1 − x As ballast layer is adjusted to give the appropriate intervalley energy separation. Al 0.3 Ga 0.7 As and Al 0.35 Ga 0.65 As emitter ballast layers incorporated in HBT structures have an average thermal coefficient of resistance of about 8 × 10 −3 °C −1 , which is significantly higher than that of GaAs ballast resistances. The temperature stabilizing effect of n -Al x Ga 1− x As ballast layer is assessed by measuring the d.c. current-voltage characteristics of single-emitter finger and multi-emitter finger HBTs. Large power HBTs with integrated n -Al x Ga 1− x As ballast resistors have been fabricated and an output power of up to 10 W at 0.9 GHz has been obtained.

Analytical model for electrical and thermal transients of self-heating semiconductor devices

Transients of self-heating semiconductor devices are theoretically investigated based on a feedback circuit model, which is composed of three sub-circuits describing the isothermal electrical characteristics, thermal impedance, and temperature dependence of the electrical characteristics of the devices, respectively. Analytical expressions of the frequency and transient responses have been derived for both the electrical and thermal characteristics of self-heating devices, yielding accurate methods to extract the thermal time constant in both the time and frequency domains. The model is verified by the transient electrical-response measurement of a GaInP/GaAs heterojunction bipolar transistor.

60GHz-band low noise amplifier and power amplifier using InGaP/GaAs HBT technology

In this paper, we present a 60 GHz-band low noise amplifier (LNA) and a 60 GHz-band power amplifier (PA) utilizing high performance InGaP/GaAs HBTs. The InGaP/GaAs HBTs feature a highly doped base layer, a self-aligned base contact and an undercut collector mesa structure in order to achieved low noise and high gain in the millimete-wave band. By adjusting the collector current of each HBT in the LNA to the optimum value a noise figure as low as 5.8 dB with a gain of more than 25 dB was obtained. The PA exhibited a linear gain of more than 15 dB with P1dB of 13 dBm in the 60 GHz-band.

Giga-bit class ultra high speed signal wireless distribution by using NRD guide technology at 60GHz

A giga-bit class ultra high speed data distribution has been successfully demonstrated at 60GHz by using the nonradiative dielectric waveguide (NRD guide) technologies. An emphasis is placed on a high speed performance of an ASK modulator and a stability of a Gunn oscillator. By assembling these circuit components, ultra high speed NRD guide transmitter and receiver have been fabricated, and it was confirmed that these NRD guide front ends have great advantage of high speed operation capacity beyond 1Gb/s. Moreover, an SDI (Serial/Digital Interface) signal with a bit rate of 1.48 Gb/s was distributed successfully to drive a high resolution HDTV display at 60GHz.

A High Efficiency InGaP/GaAs HBT Power Amplifier MMIC for the 5GHz Wireless-LAN Application

An InGaP/GaAs two-stage HBT linear power amplifier MMIC for the 5GHz Wireless-LAN Application was developed. By using a novel linearizer and a small-size via-hole technology, the power amplifier showed high output power (19dBm) with high power-added-efficiency (PAE : 18.5%), sufficient gain (21.0dB) and high linearity (4.78% error vector magnitude : EVM) at supply voltage 3.3V. It is the highest PAE in the power amplifier MMIC for the 5GHz Wireless-LAN application ever reported.