Combination of cognitive mm-Wave MIMO Phased Array systems with Optical Sensing solutions is proposed toward new functionalities for environmental perceptions and ubiquitous interactions. The resulting paradigms will operate the unification of mm-Wave and optical sensing solutions for enabling emerging technologies relative to interactions of humans with smart devices and systems in randomly changing environments. Perspectives for Autonomous Vehicles with Advanced Driver Assistance Systems (ADAS) including Gesture-Recognition (GR) through ubiquitous interactions based on hybrid cognitive mm-Wave RFIC technologies and optical systems are drawn. Several hardware realizations of mm-Wave phased-arrays are built and co-assembled with optical systems for smart data fusion and real-time co-array signal processing for autonomously secure decision making process. Unified modeling and measurement platform is proposed with the concept of Multi-Physics (EM-Thermal-Mechanical) Numerial-Co-Simulation-Clone (NCSC), seen as the counter-part of the functional hardware, which enables 4D (space-time evolution) Virtual Prototyping (VP) of augmented reality.

This chapter presents the results of a study in which the temperature and the microdisplacements of the chip surface of high-frequency power electronic components used in radar and telecommunication systems are measured. Several techniques are applied. Their advantages, disadvantages and shared fields of application are discussed. Results from several samples show that the different approaches converge. The originality of this study is that the measurements of chip surface temperature and displacement are obtained simultaneously. This approach makes it possible to then calculate the thermal resistance of an electronic component and characterize the evolution of this resistance over component lifetime.

Here, a new Faraday's cage using carbon nanotubes (CNTs) for radio frequency isolation is demonstrated. Densely packed CNTs were implemented on a guard ring structure. An antenna acts as a radiative source, while a receiving probe placed inside a CNT enclosure was used to measure the received signal. A total of 5-10 dB improvement in isolation was observed with the CNT enclosure, similar to what was obtained in an equivalent test structure with an aluminum enclosure. Such CNT isolation scheme could be implemented in densely packed three-dimensional circuits and packages, suitable for compact and light weight radar applications.

Because of their temperature sensitivity, investigation of thermal effects on electrolytic aluminum capacitors is required using ageing tests. In general, a reliability assessment methodology for these components is carried out during ageing tests, which reports dimensions and weight characterizations, electrical parameter measurement (capacitance and equivalents series resistance (ESR)) and identification of electrolyte's chemical components. However, this chemical analysis typically focuses on the main solvent and salts, without considering the percentage of the other substructures. In this paper, physical characteristics and capacitance has slightly changed according to test's severity unlike ESR which remained constant. Proton Nuclear Magnetic Resonance ( 1 H NMR) spectroscopy was performed, giving information about electrolyte's composition and percentage of identified substructures based on integral calculation of corresponding peaks in the resulting spectrum. The results show that the percentage of some electrolyte's substructures has outstandingly changed for all aged capacitors compared to unaged electrolyte, but not necessarily in the same way. The interpretation of the chemical variation and its influence on physical and electrical characteristics are presented, describing the relationship between mechanisms and modes of failures.

In many areas, the market for high-power electronic embedded systems requires them to be both highly compact and reliable. To strike the right compromise, manufacturers use component technologies that are increasingly compact, with well-defined lifetimes in the conditions specified by the supplier. However, in most cases, the reliability of the component depends on the operational profile of the system. In our case study, the technology considered is that of aluminum capacitors with liquid electrolyte, built in a compact cuboid case. Proper understanding of the reliability of this technology is a necessary step toward ensuring that the high-power electronic system operates properly. To this end, we conduct a reliability study that begins by studying the technology in order to identify the parameters that should be monitored when performing aging tests on this component. The data provided by this study are then used to establish a deterioration model as a function of the operational conditions.

AlGaN/GaN technology provides a lot of power density, which causes a thermal effect and degrades the whole electronic characteristics of the component. The local heating source appears when the component is biased. Moreover, radar applications work in pulsed rate and emphasize the impact of this source. So it is important to measure the temperature in transient mode, close to this local source as reliable as possible In this paper we present a review of the more reliable methods for time-resolving the thermal characterization of semiconductor devices for radar applications.

This paper presents a heterodyne measurement system of the pulse-to-pulse (P2P) stability and its application to time-domain measurements of a GaN HEMT microwave power amplifier. Envelope and P2P stability measurements are performed for an irregular RF pulse train which integrates a long silence between each pulse sequence. This paper is focused on the impact of RF pulse width and duty cycle on each pulse sequence. Coherent measurements of time-domain envelope and P2P stability are performed on a 10W S-band GaN power amplifier. Indeed, one aim of this work is to illustrate the great impact of temperature and trapping effects on the envelope response and P2P stability of GaN power amplifiers.

GaN High Electron Mobility Transistors (HEMTs) are very promising for radiofrequency applications and especially RADAR operation due to their ability to work at high power densities. However, parasitic effects like traps are a common issue on this type of technology. They have to be properly characterized in order to be compensated. Several measurement methods exists like DLTS or DLOS, mostly consisting in a measurement of a current transient at different junction temperatures. This paper presents a comparison between different extraction algorithms for trapping signatures and the possible impact of their imprecision when extracting the activation energy on measurement data. Furthermore, a more physical model for trap extraction will be presented with its limitations.

Gearing towards compact synthetic aperture radar designs for airborne and spaceborne applications, the effect of electromagnetic interferences in radar components is exemplified. Here, a new solution that improved RF isolation over classical Faraday cage is demonstrated, through the use of a carbon nanotube based cavity.

We demonstrate a proof of concept to implement carbon nanotubes (CNT) in radio frequency (RF) integrated circuits to achieve improved electromagnetic isolation. A densely packed CNT fence-wall was designed on a typical via-fenced guard structure, to create RF isolation between two transmission lines. Both simulations and measurements have shown to further reduce forward and backward coupling by 10 dB over current techniques in the 1-10 GHz range. Such CNT isolation scheme could be implemented in densely packed three-dimensional circuits and packages.

A new isolation scheme to improve radio frequency isolation using high aspect carbon nanotube structures is demonstrated. Carbon nanotubes were designed on top of conventional via-fenced guard trace, and showed 10 dB improvement in radio frequency isolation over conventional via-fencing techniques. This shield made of carbon nanotubes have shown to attain similar isolation performance compared to that of Kovar, a common metal used as a guard ring, or cavity in radio frequency integrated circuits. With weight density less than a quarter to that of metals, complementary use of such CNT forest could lead to significant weight reduction in RF packages.