K.W. Chang

High-performance in W-band monolithic pseudomorphic InGaAs HEMT LNA's and design/analysis methodology

High-performance W-band monolithic one- and two-stage low noise amplifiers (LNAs) based on pseudomorphic InGaAs-GaAs HEMT devices have been developed. The one-stage amplifier has a measured noise figure of 5.1 dB with an associated gain of 7 dB from 92 to 95 GHz, and the two-stage amplifier has a measured small signal gain of 13.3 dB at 94 GHz and 17 dB at 89 GHz with a noise figure of 5.5 dB from 91 to 95 GHz. An eight-stage LNA built by cascading four of these monolithic two-stage LNA chips demonstrates 49 dB gain and 6.5 dB noise figure at 94 GHz. A rigorous analysis procedure was incorporated in the design, including accurate active device modeling and full-wave EM analysis of passive structures. The first pass success of these LNA chip designs indicates the importance of a rigorous design/analysis methodology in millimeter-wave monolithic IC development. >

A W-band single-chip transceiver for FMCW radar

A monolithic microwave integrated circuit (MMIC) chip containing a W-band voltage controlled oscillator (VCO). transmit amplifiers, a receiver low noise amplifier and a mixer is discussed. It is used as the front-end of a homodyne FMCW radar for target range and range rate sensing applications. The 6.9-mm*3.6-mm monolithic chip was fabricated using 0.1- mu m pseudomorphic InGaAs-AlGaAs-GaAs HEMT process technology. The transmitter output power is more than 10 dBm for frequencies in the range 90-94 GHz, and maximum tuning bandwidth is 500 MHz for the VO. The receiver channel has 6-dB conversion gain when the output transmitting power is 10 dBm. A compete radar system has been tested based on the single-chip MMIC front-end. The calculated range and range rate are in good agreement with the measurement data.<<ETX>>

A W-band monolithic downconverter

The design, fabrication, and evaluation of a fully integrated W-band monolithic downconverter based on InGaAs pseudomorphic HEMT technology are presented. The monolithic downconverter consists of a two-stage low-noise amplifier and a single-balanced mixer. The single-balanced mixer has been designed using the HEMT gate Schottky diodes inherent to the process. Measured results of the complete downconverter show conversion gain of 5.5 dB and a double-sideband noise figure of 6.7 dB at 94 GHz. Also presented is the downconverter performance characterized over the -35 degrees C to +65 degrees C temperature range. The downconverter design was a first pass success and has a high circuit yield. >

A 62-GHz monolithic InP-based HBT VCO

A monolithic V-band VCO using InP-based HBT technology has been designed, fabricated, and tested. This VCO delivers a peak output power of 4 dBm at a center frequency of 62.4 GHz with a tuning range of 300 MHz. The measured phase noise shows -78 dBc/Hz at 100 kHz offset and -104 dBc/Hz at 1 MHz offset. To our knowledge, this is the highest frequency fundamental-mode oscillator ever reported using bipolar transistors. >

A 0.1-W W-band pseudomorphic HEMT MMIC power amplifier

The authors have designed and fabricated monolithic power amplifiers using pseudomorphic InGaAs power HEMTs (high-electron-mobility transistors) with record power and gain performance at W-band frequency. The two-stage amplifier has a small-signal gain of 9 dB and can deliver 0.1-W output power with 5.9-dB associated gain and 6.6% power-added efficiency at 93.5 GHz. The successful first pass design of the W-band MMIC (monolithic microwave integrated circuit) power amplifier is due to the superior device performance and the millimeter-wave monolithic power amplifier design techniques.<<ETX>>

A high performance and low DC power V-band MMIC LNA using 0.1 mu m InGaAs/InAlAs/InP HEMT technology

We report the design and performance of state-of-the-art V-band MMIC LNAs using 0.1- mu m gate length pseudomorphic In/sub 0.60/Ga/sub 0.40/As/In/sub 0.52/Al/sub 0.48/As/InP HEMTs. The three-stage V-band LNA demonstrated an average of 3.0 dB noise figure between 56-64 GHz with 24-25.5 dB associated gain with a noise figure of 2.7 dB measured at 62 GHz. Furthermore, the DC power dissipation of this circuit was only 19.5 mW which is less than one-third the DC power dissipation of InGaAs/AlGaAs/GaAs HEMT versions. These results demonstrate the excellent potential of InP HEMT technology for millimeter-wave and low DC power applications.<<ETX>>

An ultra low noise W-band monolithic three-stage amplifier using 0.1- mu m pseudomorphic InGaAs/GaAs HEMT technology

An ultra-low-noise W-band monolithic three-stage amplifier based on 0.1- mu m pseudomorphic InGaAs/GaAs high electron mobility transistor (HEMT) devices has been developed. This amplifier has a measured noise figure of 3.5 dB with an associated small signal gain of 21 dB at 94 GHz. This is the best reported performance of a monolithic W-band high-gain low-noise amplifier (LNA), significantly improved compared with previous records in terms of noise figure and associated gain. Accurate modeling techniques were essential to the success of this monolithic circuit design, which included active device and full-wave electromagnetic analysis of passive matching structures. The measured results of the W-band three-stage monolithic microwave integrated circuit (MMIC) LNA from 91 to 97 GHz are presented.<<ETX>>

A W-band monolithic, singly balanced resistive mixer with low conversion loss

We report the design, measured and simulated performance of a novel W-band monolithic, singly balanced resistive FET mixer utilizing 0.1-/spl mu/m pseudomorphic AlGaAs/InGaAs on GaAs HEMT technology. At an LO drive of +8 dBm, this mixer has exhibited a minimum measured conversion loss of 12.8 dB, nearly a 10 dB improvement over previously reported data in this frequency range. Furthermore, the mixer figure of merit, defined as P/sub 1-dB,in/-P/sub LO/, is at least +2 dBm, which is nominally 6 dBm better than that of comparable diode mixers at W-band. These results indicate the excellent potential of this mixer for integration with other circuit components in fully monolithic subsystems.<<ETX>>

A novel W-band monolithic push-pull power amplifier

Monolithic W-band push-pull power amplifiers have been developed using 0.1-/spl mu/m AlGaAs/InGaAs/GaAs pseudomorphic T-gate power HEMT technology. The novel design approach utilizes a push-pull topology to take advantage of a virtual ground between the device pair, eliminating the series feedback of the via hole inductance, and thus improving the performance of the power amplifier at millimeter-wave frequencies. For a two-stage design presented in this paper, the measurement results show a small signal gain of 13 dB and a saturated output power of 19.4 dBm at 90 GHz. The best power added efficiency of 13.3% has been achieved at an output power of 18.8 dBm under a lower bias condition. The gain and efficiency results represent state-of-the-art performance. These are the first reported monolithic push-pull amplifiers at millimeter-wave frequencies. >

Low phase noise millimeter-wave frequency sources using InP based HBT technology

A family of millimeter-wave sources based on InP HBT technology has been developed. These sources include 40-GHz, 46-GHz, 62-GHz MMIC fundamental mode VCOs, and a 95-GHz frequency source module using a 23.8-GHz InP HBT MMIC DRO in conjunction with a GaAs based HEMT MMIC frequency quadrupler and W-band output amplifiers. Good phase noise performance was achieved due to the low 1/f noise of the InP-based HBT devices. To our knowledge, this is the first demonstration of millimeter-wave sources using InP-based HBTs.