Progettazione di un LNA nella banda 1.8-2.2 GHz con tecnologia CMOS 0.12um

The subject of this work is a low noise amplifier (LNA), operating in the frequency range 1.8 – 2.1 GHz. The CMOS 0.12 μm is used in respect to the low cost of the final device. Among the specifications, a variable gain and an adjustable working frequency are required. In particular, four different working modes are provided: 1.8, 1.9 and 2.1 GHz high gain and 2.1 GHz low gain. The amplifier is designed to be used as the first stage of a receiver for mobile telephony. For this reason a low power consumption is taken into consideration (low supply voltage and low drain currents). In order to obtain a good input impedance matching in all the four operating modes, a circuital topology is chosen, that allows the use of a single external matching network, realized with standard passive components (E12 standard). Moreover, a LC-resonating load is used to maximize the gain at the working frequency and for its band-pass behavior, useful in our case. All the simulations are performed taking into account the parasitic effects of the input pads and of the bond wires, since they have a great influence on the input impedance of the LNA. A simple digital circuit, integrated on-chip, is used to select the operating mode of the LNA by means of two input pins. In conclusion a layout of the amplifier is realized: particular attention is paid into reducing the parasitic resistance of the metal interconnections in order to minimize the noise. A very good 1 dB Noise Figure is obtained. ---------------------------------------------- Oggetto di questo lavoro è un amplificatore a basso rumore (LNA), funzionante a frequenze comprese tra 1,8 e 2,1 GHz. La tecnologia utilizzata è CMOS a 0.12 μm, la quale consente notevoli vantaggi dal punto di vista del costo del dispositivo finale. Tra le specifiche sono richieste la possibilità di scegliere il livello di guadagno e la frequenza di funzionamento desiderate. In particolare sono previste quattro differenti modalità operative: alto guadagno, alle frequenze di 1,8, 1,9 e 2,1 GHz e basso guadagno alla frequenza di 2.1 GHz. L’amplificatore è progettato per essere utilizzato a monte di un ricevitore per dispositivi di telefonia mobile portatili (telefoni cellulari). Per questo motivo si è prestata attenzione alla riduzione dei consumi (bassa tensione di alimentazione e ridotta corrente assorbita). Al fine di ottenere un buon adattamento di impedenza d’ingresso in ognuna delle quattro modalità di funzionamento è stata scelta una soluzione circuitale che consente l’uso di una singola rete esterna, realizzata con componenti passivi in standard E12. Inoltre è stato scelto un tipo di carico LC risonante per esaltare il guadagno in un intorno della frequenza selezionata e per il suo comportamento passa-basso, vantaggioso nel nostro caso. Tutte le simulazioni svolte tengono in considerazione gli effetti parassiti dovuti ai pad di ingresso e alle interconnessioni tra pin e pad, in quanto questi danno un contributo notevole all’impedenza d’ingresso del circuito. Un semplice circuito digitale integrato sullo stesso chip consente di selezionare il modo operativo dell’LNA tramite due appositi pin. Infine è stato realizzato un layout dell’amplificatore con accorgimenti per ridurre il rumore dovuto alle resistenze parassite delle interconnessioni. È stata ottenuta una cifra di rumore finale di solo 1 dB

Federalism and State Legislative Opposition to the Affordable Care Act: The Political Value of Legal Strategy

In the last six years, the American states have been the protagonists of a renewed push for sovereignty that has involved the enactment of different types of legislation to avoid the implementation of the federal health law within the state. George Mason University’s professors Paul L. Posner and Timothy Conlan have identified the causes of state resistance in the ideological conflicts reflecting growing political polarization in Washington: “Federal programs have become a new battleground for states to demonstrate their fidelity to very different ideologies and political alliances.”1 The literature has upheld the legislative push against the reform as “capable of contributing under certain conditions to safeguarding federalism principles.”2 This research contributes to the literature on contemporary assertions of state sovereignty because it argues that the state legislative activity in opposition to federal law is a mechanism that cannot only safeguard federalism but can also enrich constitutional debate. This study combines an understanding of political science and legal method in an effort to provide a multi-disciplinary dimension to an understanding of the contemporary states’ rights phenomenon

Classical and quantum perturbations to the primordial universe

In this Ph.D. thesis we analyse both classical and quantum effects relevant for the study of cosmological perturbations. We choose this particular topic because, through the analysis of cosmological perturbations, it is possible to explore a wide range of different physical phenomena. Moreover, they are a central and important piece in the puzzle of the history of the universe. The most obvious relevance of cosmological perturbations is the study of structure formation and the large scale structure of the universe. In this regard, such perturbations are related to primordial gravitational waves and primordial magnetic fields. Given their dependence on pre-recombination phenomena, they could give us some information on the universe before hydrogen recombination. Classical perturbations have been widely studied in literature, with the main focus on isotropic cosmological models. While this is usually a good approximation, the presence of a primordial magnetic field causes a coupling between different algebraic modes of the usual decomposition, connecting density perturbations, primordial magnetic fields and primordial gravitational waves. Moreover, the presence of the magnetic field requires the use of an anisotropic cosmological model. While small, these relations are important in the evolution of anisotropic structures. Furthermore, such primordial seeds of the magnetic fields are widely believed to be the origin of the magnetic fields measured today in galaxies. In the first part of this thesis, we analyse these relations, together with the possible effects that a non ideal, i.e. viscous, cosmological fluid could have on the growth of perturbations. We focus our attention to a Bianchi I model, improving the results of some preceding papers. The second part of the thesis focuses on the semiclassical approximation of quantum gravity. Quantum effects are believed to influence the birth and dynamics of perturbation seeds and, in general, the dynamics of the primordial universe. This way, the mathematical scheme used to represent these effects is a central point in the description of quantum gravity regarding such seeds. Furthermore, even more care is required to split the WKB action between embedding variables and physical degrees of freedom, and in many models the quantum gravity corrections to the Schrödinger equation violate the unitarity of the system evolution. This decomposition shares some similarities with the Born-Oppenheimer approximation of molecular physics. We perform a critical analysis of two different ways to apply this decomposition. In particular, we analyse limits and perspectives of the different proposals to solve the non unitarity problem, even comparing expansions in different fundamental physical constants (Planck constant and mass). We find the source of non-unitary effects in a common assumption in the definition of WKB time, and we propose an alternative formulation. Also, we show how the usual assumptions of classicality of the physical quantities must be handled with care, focusing our attention to the implementation of the classical background in the perturbation scheme. Studies in this research field are very important because they could bind CMB measurements and primordial gravitational waves to quantum gravity, bringing us finally an experimental playground

Book Review of Conservative Innovators, by Ben Merriman. Chicago, IL: University of Chicago Press, 2019, 232 pp. $32.50 paperback

What are the effects of the current political climate of hyper-polarization on intergovernmental relations? In Conservative Innovators, Assistant Professor of the University of Kansas Ben Merriman argues that polarization has “everything to do with state governments” and it has encouraged heightened intergovernmental disagreement. The main assumption of the book is that state-level conservative figures, such as state governors and attorney generals, have developed a repertoire of strategies to challenge the Obama administration’s policies during the years 2009-2016, which have transformed partisan disagreement into a conflict between different levels of government. This has been possible, Merriman argues, because the Obama era coincided with the consolidation of a long process in which the executive powers of state officials had grown along with the expansion of the federal government

How lead generation can be the link between marketing and sales through the customer experience? A case study of Talentia Software Italy

Digitalization is the use of digital technology to adapt and grow a business model. Businesses use digitalization to create value-producing opportunities through the information they collect from customer interactions by optimizing their marketing and selling processes. Potential customers have changed the way that they research and select products and services, so companies must respond and adapt. Competition has increased so creating win-win customer relationships is even more important today than ever before. Due to the uniqueness of the contemporary digital economy, brands may need to redefine what profit means for both company and consumer. The Customer Lifetime Value Analysis is the potential value of all future profit that an individual customer will generate over the life of potential customer compared with the benefit expected for both parties. First of all, the premise of the paper considers the process of scouting for new and potential customers value for money and value for time are highly relevant for brands. The most important recommended methods are Advertising (it helps to offer a message that not only hits on brands target customers, but also showcases the value brands can offer them); Networking and referral (to pick up customers with the highest retention rates; what is more, referral customers tend to purchase more over time and in turn become a source of additional referrals); Create an agreement with “host beneficiary” (another business with the same target customer will use their database to promote another one business); Strategic alliances (while a host beneficiary relationship is generally a onetime or short-term commitment, strategic alliances can sometimes last for many years). Then, the aim of the paper is to demonstrate the relevance of the role of the Business Developer through Lead generation. It is more profitable if brands take the approach of using live chat services, direct help options with customer representatives present to solve any incoming query. This works by increasing engagement on the customer level and increases brand word of mouth promotion for more leads and better business development. Moreover, the paper analyses the roles of the Demand Generation Manager, Inside Sales Representative and more are at the core of Business Development. The methodology used in the paper is a descriptive empirical analysis. After a view on the important variables about business development analysis, lead generation and customers experience, the Authors describe the strategies adopted in the case history (Talentia Software Italy). This empirical analysis aims to confirm the validity of the concept that confirms a really and strong relation between lead generation attitudes and marketing sales

Linear perturbations of an anisotropic Bianchi I model with a uniform magnetic field

In this work, we study the effect of a magnetic field on the growth of cosmological perturbations. We develop a mathematical consistent treatment in which a perfect fluid and a uniform magnetic field evolve together in a Bianchi I universe. We then study the energy density perturbations on this background with particular emphasis on the effect of the background magnetic field. We develop a full relativistic solution which refines previous analysis in the relativistic limit, recovers the known ones in the Newtonian treatment with adiabatic sound speed, and it adds anisotropic effects to the relativistic ones for perturbations with wavelength within the Hubble horizon. This represents a refined approach on the perturbation theory of an isotropic universe in GR, since most of the present studies deal with fully isotropic systems.Comment: Small modifications. Final version, published by EPJ