January 01, 2011

Improved External Base Resistance Extraction for Submicrometer InP/InGaAs DHBT Models

  • Dupuy J.
  • Johansen T.
  • Konczykowska A.
  • Krozer V.
  • Nodjiadjim V.
  • Riet M.

An improved direct parameter extraction method is proposed for III-V heterojunction bipolar transistor (HBT) external base resistance Rbx extraction from forward active S-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 Z11 - Z12 reduces to the external base resistance at the collector current Ic = Ip/(1 - X0), where Ip is a characteristic current and X0 is the zero-current distribution factor given as the ratio of the emitter to the collector area. The determination of the parameters Ip and X0 from experimental S-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 S-parameters as well as the maximum stable power gain/maximum available power gain in the frequency range from 40 MHz to 110 GHz.

View Original Article

Recent Publications

August 09, 2017

A Cloud Native Approach to 5G Network Slicing

  • Francini A.
  • Miller R.
  • Sharma S.

5G networks will have to support a set of very diverse and often extreme requirements. Network slicing offers an effective way to unlock the full potential of 5G networks and meet those requirements on a shared network infrastructure. This paper presents a cloud native approach to network slicing. The cloud ...

August 01, 2017

Modeling and simulation of RSOA with a dual-electrode configuration

  • De Valicourt G.
  • Liu Z.
  • Violas M.
  • Wang H.
  • Wu Q.

Based on the physical model of a bulk reflective semiconductor optical amplifier (RSOA) used as a modulator in radio over fiber (RoF) links, the distributions of carrier density, signal photon density, and amplified spontaneous emission photon density are demonstrated. One of limits in the use of RSOA is the lower ...

July 12, 2017

PrivApprox: Privacy-Preserving Stream Analytics

  • Chen R.
  • Christof Fetzer
  • Le D.
  • Martin Beck
  • Pramod Bhatotia
  • Thorsten Strufe

How to preserve users' privacy while supporting high-utility analytics for low-latency stream processing? To answer this question: we describe the design, implementation and evaluation of PRIVAPPROX, a data analytics system for privacy-preserving stream processing. PRIVAPPROX provides three properties: (i) Privacy: zero-knowledge privacy (ezk) guarantees for users, a privacy bound tighter ...