Tom Keinicke Johansen

EM simulation accuracy enhancement for broadband modeling of on-wafer passive components

This paper describes methods for accuracy enhancement in broadband modeling of on-wafer passive components using electromagnetic (EM) simulation. It is shown that standard excitation schemes for integrated component simulation leads to poor correlation with on-wafer measurements beyond the lower GHz frequency range. We show that this is due to parasitic effects and higher-order modes caused by the excitation schemes. We propose a simple equivalent circuit for the parasitic effects in the well-known ground ring excitation scheme. An extended L-2L calibration method is shown to improve significantly the accuracy of the on-wafer component modeling, when applied to parasitic effect removal associated with the excitation schemes.

Oscillator Phase Noise: A Geometrical Approach

We construct a coordinate-independent description of oscillator linear response through a decomposition scheme derived independently of any Floquet theoretic results. Trading matrix algebra for a simpler graphical methodology, the text will present the reader with an opportunity to gain an intuitive understanding of the well-known phase noise macromodel. The topics discussed in this paper include the following: orthogonal decompositions, AM-PM conversion, and nonhyperbolic oscillator noise response.

Analysis and design of wide-band SiGe HBT active mixers

The frequency response of SiGe HBT active mixers based on the Gilbert cell topology is analyzed theoretically. The time-varying operation of the active mixer is taken into account by applying conversion matrix analysis. The main bandwidth-limiting mechanisms experienced in SiGe HBT active mixers performing frequency conversion of wide-band signals is discussed. The analysis is verified by computer simulations using a realistic high-frequency large-signal SiGe HBT model. An active mixer design based on the Gilbert cell topology modified for wide-band operation using emitter degenerated transconductance stage and shunt feedback load stage is discussed. Experimental results are given for an active mixer implemented in a 0.8-/spl mu/m 35-GHz f/sub T/ SiGe HBT BiCMOS process.

InP-DHBT-on-BiCMOS Technology With

This paper presents a novel InP-SiGe BiCMOS technology using wafer-scale heterogeneous integration. The vertical stacking of the InP double heterojunction bipolar transistor (DHBT) circuitry directly on top of the BiCMOS wafer enables ultra-broadband interconnects with <; 0.2 dB insertion loss from 0-100 GHz. The 0.8 × 5 μm2 InP DHBTs show fT/fmax of 400/350 GHz with an output power of more than 26 mW at 96 GHz. These are record values for a heterogeneously integrated transistor on silicon. As a circuit example, a 164-GHz signal source is presented. It features a voltage-controlled oscillator in BiCMOS, which drives a doubler-amplifier chain in InP DHBT technology.

f_{T}/f_{\max}

The dynamic equations governing the cross-coupled quadrature harmonic oscillator are derived assuming quasi-sinusoidal operation. This allows for an investigation of the previously reported tradeoff between close-to-carrier phase noise and quadrature precision. The results explain how nonlinearity in the coupling transconductances, in conjunction with a finite amplitude relaxation time and de-tuning of the individual oscillators, cause close-to-carrier AM-to-PM noise conversion. A discussion is presented of how the theoretic results translate into design rules for quadrature oscillator ICs. SPECTRE RF simulations verify the developed theory.

of 400/350 GHz for Heterogeneous Integrated Millimeter-Wave Sources

The paper presents analysis and design of a Q-band subharmonic mixer (SHM) with high conversion gain. The SHM consists of a local oscillator (LO) frequency doubler, RF pre-amplifier, and single-ended mixer. The SHM has been fabricated in a high-speed InP double heterojunction bipolar transistor (DHBT) technology using coplanar waveguide structures. To the best of our knowledge, this is the first demonstration of an SHM using InP DHBT technology at millimeter-wave frequencies. The measured results demonstrate a conversion gain of 10.3 dB at 45 GHz with an LO power of only 1 mW. The fundamental mixing product is suppressed by more than 24 dB and the output is around . The mixer is broadband with a conversion gain above 7 dB from 40 to 50 GHz. The conversion gain for the fabricated SHM is believed to be among the best ever reported for millimeter-wave SHMs.

Nonlinear analysis of a cross-coupled quadrature harmonic oscillator

In this letter, a novel modified Marchand balun configuration with tunable phase balance is analyzed and verified experimentally. It is proposed to add a shunt susceptance in between the two couplers of the Marchand balun. This allows for a change in the phase balance which, to first order, is linear with the susceptance, while the magnitude balance is kept constant. To verify the proposed configuration, a lumped element Marchand balun has been fabricated using a SiGe BiCMOS technology. The balun design is centered around 9.4 GHz, with an insertion loss of 6.0 dB. The phase difference between the output ports can be changed from 175.8° to 183 ° whereas the magnitude imbalance is kept almost constant at 0.3 dB. The balun performs well in the range from 7 to 11 GHz, where it is possible to tune the phase to exactly 180°.

A High Conversion-Gain

E-band wireless communications will become important as the microwave backhaul for high-speed data transmission. One of the most critical components is the front-end power amplifier in this system. The paper analyzes different technologies with potential in the E-band frequency range and present a power amplifier design satisfying the E-band system specifications. The designed power amplifier achieves a maximum output power of ges 20 dBm with a state-of-the-art power-added efficiency of 15%. The power is realized using InP DHBT technology. To the best of our knowledge it is the highest output power and efficiency reported for an InP HBT power amplifier in this frequency range. The predicted power-added efficiency is higher than that of power amplifiers based on SiGe HBT and GaAs pHEMT technologies. The design shows the capabilities of InP DHBT for power amplifier applications as an alternative to HEMT based technologies in the millimeter-wave frequency range.

Q

We report on a consistent large-signal and small-signal modeling and parameter extraction method for high-speed InP DHBT valid to 110 GHz. Electromagnetic simulation is applied to predict the embedded network model caused by pad parasitics. Applying direct parameter extraction on the de-embedded device response leads to accurate small-signal model description of the InP DHBT. We have solved the problem of consistent transit time modeling by a two step process. A parameter extraction approach is described for the Agilent ADS2004A HBT model, which assures consistency between large-signal and bias-dependent small-signal modeling

-Band InP DHBT Subharmonic Mixer Using LO Frequency Doubler

An improved direct parameter extraction method is proposed for III-V heterojunction bipolar transistor (HBT) external base resistance <i>R</i>_bx extraction from forward active <i>S</i>-parameters. The method is formulated taking into account the current dependence of the intrinsic base-collector capacitance found in III-V HBTs with a fully depleted collector. It is shown that the real part of <i>Z</i>₁₁ - <i>Z</i>₁₂ reduces to the external base resistance at the collector current <i>Ic</i> = <i>Ip</i>/(1 - <i>X</i>₀), where <i>Ip</i> is a characteristic current and <i>X</i>₀ is the zero-current distribution factor given as the ratio of the emitter to the collector area. The determination of the parameters <i>Ip</i> and <i>X</i>₀ from experimental <i>S</i>-parameters is described. The method is applied to high-speed submicrometer InP/InGaAs DHBT devices and leads to small-signal equivalent circuit models, which accurately predicts the measured <i>S</i>-parameters as well as the maximum stable power gain/maximum available power gain in the frequency range from 40 MHz to 110 GHz.