We report in this paper, the performance of AlGaN/GaN HFETs in the context of high power, low noise and high temperature operations, along with a comparison of their characteristics with other conventional technologies. Finally, a single stage modulator driver for long haul optical communications is presented as an example of application of the GaN-based devices high power handling capabilities.

We report the investigation of major dispersion mechanisms such as self-heating, trapping, current collapse, and floating-body effects present in AlGaN/GaN HFETs. These effects are analyzed using DC/Pulsed IV, load-pull, low-frequency noise systems, and a cryogenic probe station. This study leads to a better understanding of the device physics, which is critical for accurate large-signal modeling and device optimization.

This paper proposes a technique for two-stage operational amplifiers (OPAMPs) to optimize power consumption according to various channel conditions of wireless communication systems. The proposed OPAMP has the ability of reducing the quiescent current of each stage independently by introducing additional common-mode feedback, therefore more optimization is possible according to the channel conditions than conventional two-stage OPAMPs. The simulations verify the benefits of the technique. As a proof-of-concept topology, the proposed OPAMPs were used in a channel-selection filter for a multi-standard mobile-TV receiver. The power consumption of the filter, 3.4–5.0 mW, was adjustable according to the bandwidth, the noise, and the jammer level. The performance of the filter meets the requirements and verifies the effectiveness of the proposed approach. The filter was fabricated in 0.18-µm CMOS and occupied 0.64 mm2.

Electronics packaging evolution involves both systems, technology & materials considerations. In this paper, we present a novel 3D integration approach for system-on-package (SOP) based solutions for wireless communication applications. This concept is proposed for the 3D integration of a C band Wireless LAN (WLAN) RF front-end module by means of stacking LCP (Liquid Crystal Polymer) substrates using µBGA technology. LCP substrates fabrication, high Q inductor design and the associated physical based modeling are detailed. Then stacking techniques using µBGA technology is presented. Characterization and modeling of RF vertical board-to-board transition, using µBGA process are detailed and show that this vertical transition is suitable for C-band wireless communication applications.