Amin Ezzeddine

Ultra-Broadband GaAs HIFET MMIC PA

This paper reports the first MMIC using the HIFET (high-voltage, high-impedance FET) concept with very broadband power performance and small die size. This GaAs MMIC power amplifier has a gain of 21dB plusmn 1dB and over 2W of P1dB over the entire 30 MHz to 2.5 GHz frequency band with 20% efficiency, at a bias voltage of +20V. We believe that this is the first MMIC ever reported which achieves this combination of instantaneous bandwidth, output power, and efficiency, within a die size of 4 mm2

10W ultra-broadband power amplifier

We report the design and performance of an ultra-broadband power amplifier. It achieves 10 Watts output power with 21dB ± 1.5dB gain from 20 MHz to 3000 MHz. At lower frequencies from 20 to 1000 MHz the output power is 15 Watts with 22% efficiency. To achieve this performance, we employ a new design concept to control the device impedance and the power combiner impedance to be naturally 50 Ohms, such that no impedance matching is needed. Also, we developed a broadband microwave balun as a push-pull power combiner, which doubles as an impedance transformer. We believe the combination of output power, bandwidth and efficiency is the best reported to date.

High-Voltage FET Amplifiers for Satellite and Phased-Array Applications

The high-voltage FET amplifier (HVFA) configuration for power amplifier applications in satellite communications and phased-array systems can offer substantial improvement in DC-to-RF conversion efficiency. A proof-of-concept experiment, design considerations, and the RF results of MIC implementation at C- and X-band are reported. An X-band MMIC HVFA design is also presented.

Vertical balun and Wilkinson divider

We report the development of a novel broadband 3D vertical balun exhibiting superior performance due to ground plane removal and unique 3D features. The balun offers /spl plusmn/5 degrees phase and /spl plusmn/0.5 dB amplitude imbalance, from 2.0-2.7 GHz. In addition, we present the performance of a 3D X-band 4-way Wilkinson divider.

Ku-band MMIC's in low-cost, SMT compatible packages

MM-wave components are very expensive due to the high package and assembly cost. This paper describes a 0.25 /spl mu/m PHEMT Ku-band 2-watt PA, and a 2.2 dB NF LNA MMIC in a low-cost SMT package (

Properties of the embedded transmission line (ETL)-an offset stripline with two dielectrics

2.00). The package has excellent thermal resistance, 0.5 C/W, return loss (20 dB), and input/output isolation (40 dB), from DC-40 GHz. We believe this is the first time such a package design has been published.

Analysis of three-dimensional embedded transmission lines (ETL's)

In three-dimensional (3-D) circuits that employ multilevel metallization, a frequently encountered transmission line configuration is the embedded transmission line (ETL), which is essentially an offset stripline topology with two dielectrics. There is no closed-form expression available for either the characteristic impedance or effective dielectric constant, since the problem is analytically complex for an exact analysis. This work provides an approximate empirical formula for both the effective dielectric constant and the characteristic impedance, and compares them with full-wave simulations of the structure. A few percent error (typically, less than 3% for Z/sub 0/, and 5% for /spl epsi//sub eff/) is observed over a wide range of transmission line parameters.

A new phase noise reduction technique for MMIC oscillators

Three-dimensional (3-D) circuits promise a significant reduction in circuit size and cost. In 3-D circuits, a few transmission line configurations are encountered including the offset stripline and the embedded transmission line (ETL), a stripline-like topology with two dielectrics. The ETL may have either two ground planes (similar to an offset stripline) or one ground plane (similar to an inverted microstrip). There is a need for an accurate solution to predict the effective dielectric constant and characteristic impedance of these transmission line structures. This paper provides an accurate (1% maximum error) closed-form empirical formula for the effective dielectric constant and compares it with full-wave simulations. In addition, this letter provides an empirical formula for the characteristic impedance and compares it with full-wave simulations of the structure. Close agreement between the two approaches is observed over a wide range of parameters.

UHiFET - A new high-frequency High-Voltage device

A novel technique for reducing oscillator phase noise has been demonstrated. The technique utilizes a pair of limiting diodes to keep the metal-semiconductor field-effect transistor operating in a linear region. An X-band monolithic microwave integrated circuit oscillator was designed, fabricated, and tested to demonstrate the concept. A reduction of 15 dB in phase noise at 5 kHz from the carrier was measured. The technique is ideal for GaAs monolithic implementation, and can also be applied to silicon bipolar-based oscillators for phase-noise reduction.<<ETX>>

Inexpensive X-band 1/2 watt PA using 3D LTCC technology

The HiFET (High-Impedance, High-Voltage FET) configuration is used to connect several semiconductor FETs both DC and RF in series, resulting in high DC bias voltage and high output impedance. The HiFET power and efficiency degrades at high microwave frequencies (i.e. > 3GHz) due to gate leakage currents. In this article, we propose a new configuration, the Universal HiFET (UHiFET), which uses an additional compensation to equalize the RF voltages and currents of all the transistor cells that are connected in series. This new approach improves the power, efficiency and linearity of the original HiFET configuration at microwave and millimeter wave frequencies. We are presenting a mathematical analysis of the UHiFET and measured data to demonstrate the effectiveness of the proposed approach.