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Nowadays, parametric macromodeling techniques are widely used to describe electromagnetic structures. In this contribution, the application of such parametric macromodeling techniques to the design of integrated inductors and radio-frequency circuit design is investigated. In order to allow such different operations, a new modeling methodology is proposed, which improves the modeling accuracy when compared to former techniques. The new methodology is tailored to the unique characteristics of the devices under study. The obtained parametric macromodel is then used in a synthesis methodology and in the design of a voltage controlled oscillator in a 0.35-μm CMOS technology

An INFN-LNF/UCLA/SAPIENZA collaboration is developing a hybrid photoinjector in X-band. A hybrid photoinjector is a novel high brightness electron source that couples a standing wave cell cavity (acting as an RF gun) directly to a multi-cell travelling-wave structure. This configuration offers a number of advantages over the split standing wave/travelling-wave system. Most notably the reflected RF transient is almost completely suppressed, thus eliminating the need for a circulator and the bunch lengthening effect that occurs in the drift section of the split system. These properties allow scaling of the device to higher field and frequencies, which should dramatically improve beam brightness. The RF coupling between the standing and the traveling wave sections is accomplished in the fourth cell encountered by the beam, with the SW section electrically coupled to it on-axis. This mode of coupling is particularly advantageous, as it is accompanied by a 901 phase shift in the accelerating field, resulting in strong velocity bunching effects on the beam that reverse the usual bunch lengthening induced after the gun exit in standard 1.6 cell photoinjectors. In this scenario, from the beam dynamics point of view, it is seen that device may produce ten’s of femtosecond beams at � 3.5 MeV and the emittance compensation dynamics remains manageable even in the presence of strong compression. We present here a survey of the device characteristics. In particular we show the results of the electromagnetic simulations, a beam dynamics analysis related to the temperature tuning of the SW and TW section, and a RF characterization using bead pull and scattering coefficient measurements of a device prototype.

The recent and dramatic increase in demand for mobile data communication, driven by consumer devices such as smartphones and tablets, is resulting in heightened technical challenges for the wireless infrastructure that lies as a bridge in-between these mobile terminals and the wired network transferring the data between final users. Several challenges arise in the design of the electronics behind the wireless infrastructure access points, or base-stations. This Chapter provides an overview of the present state, challenges and trends in the RF, analog and mixed signal electronics for wireless infrastructure and provides a frame to orient the reader of this book to the following chapters covering the specifics of the technologies involved. © 2013

International audience; Future mobile terminals will be able to communicate with various heterogeneous systems which are different by means of the algorithms used to implement baseband processing and channel coding.This represents many challenges in designing flexible and energy efficient architectures. Using the sensing phase, the mobile can sense its environment and detect the spectrum holes and use them to communicate. Current research are investigating different techniques of using cognitive radio to reuse locally unused spectrum to increase the total system capacity. They aim also to develop efficient algorithm able to maximize the quality of service (QoS) for the secondary (unlicensed) users while minimizing the interference to the primary (licensed)users. However, there are many challenges across all layers of a cognitive radio system design, from its application to its implementation.