Kozo Makiyama

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This paper presents two oscillators (OSCs) and a high power amplifier (PA) for millimeter-wave transceivers. The circuits were designed with a grounded coplanar waveguide (GCPW) and 0.12-μm GaN HEMT technology. One OSC, which was based on a simple series source feedback topology, oscillated at a frequency of 74.5 GHz with an output power of 2.2 mW(More)
Abstract — The state-of-the-art GaN high electron mobility transistors (GaN-HEMTs) technology for millimeter-wave amplifiers is described in this paper. A high maximum frequency of an oscillation (fmax) device with high breakdown voltage (BVgd) was focused on to improve the gain, efficiency, and reliability of the millimeter-wave amplifier. In this study,(More)
This paper presents W-band monolithic microwave integrated circuit (MMIC) amplifiers with grounded coplanar waveguide (GCPW) in 0.12µm GaN HEMT technology. A fabricated four-stage low-noise amplifier (LNA) exhibited a record gain of 23 dB at 76.5 GHz and a first reported noise figure (NF) of 3.8 dB at 80 GHz for any W-band GaN MMIC. Another MMIC(More)
A <i>W</i>-band millimeter-wave transmitter and receiver that are based on impulse radio (IR) architecture were developed. The IR-based apparatuses have an optical-fiber input/output interface board that supports multi protocol signals (OC-192 and 10 GbE) and that implements a forward error correction (FEC), enabling 10-Gb/s data transmission both in space(More)
In this paper, we demonstrated a broadband GaN power amplifier hybrid IC with high power added efficiency (PAE) under CW operation using load-impedance change compensation technique. The external output matching circuit is composed of a transmission line, an open stub and a short stub with chip capacitors to realize both wide bandwidth and high voltage(More)
In this paper, a multi-stage amplifier in 75-nm InP-HEMT technology is described. To achieve a remarkably high gain in a submillimeter waveband, feedback reduction architectures are proposed. The small signal gain of the fabricated amplifier is 30 dB around 230 GHz, and the 3-dB bandwidth is 228 to 242 GHz. The total power consumption of the amplifier was(More)
We developed a novel electrical non-return-to-zero (NRZ) to return-to-zero (RZ) converter circuit based on a master-slave D-type flip-flop (D-FF). Its decision and re-timing function makes the converter without any delay or phase control circuitry, which are usually employed to adjust the phase alignment of data and clock. The circuit achieved 50-Gbit/s(More)
An 80 Gbit/s 1:2 demultiplexer (DEMUX) is presented that was fabricated using 0.1-/spl mu/m-gate-length InP-based HEMT technology. A data input buffer with a common-gate amplifier in front is employed to achieve a low return loss over wide frequency range and to suppress signal distortion, which is mainly caused by multiple reflections between a DEMUX chip(More)
We developed an ON/OFF pulse modulator IC using 0.1-mum-gate-length InP HEMTs for ultra-wideband impulse radio (UWB-IR) communications systems. The IC generated extremely short pulses whose full width at half maximum (FWHM) were 6.5 ps. Furthermore, our new circuit architecture that retimes output pulses at both rising and falling edges made the IC robust(More)
There is great interest in increasing the operating speed of digital circuits. Using 0.10-/spl mu/m gate-length InP HEMT technology, to date we have developed a 144-Gbit/s multiplexer (MUX), a 80-Gbit/s demultiplexer (DEMUX), a 80-Gbit/s D-type flip-flop (D-FF), and a 90-GHz T-type flip-flop (T-FF). Key aspects of the fabrication, circuit design, and(More)