Non-data aided digital feedforward timing estimators for linear and nonlinear modulations

We propose to develop new non-data aided (NDA) digital feedforward symbol timing estimators for linear and nonlinear modulations, with a view to reducing the sampling rate of the estimators. The proposed estimators rely on the fact that sufficient statistics exist for a signal sampled at the Nyquist rate. We propose an ad hoc extension to the timing estimator based on the log nonlinearity which performs better than existing estimators at this rate when the operating signal-to-noise ratio (SNR) and the excess bandwidth are low. We propose another alternative estimator for operating at the Nyquist rate that has reduced self-noise at high SNR for large rolloff factors. This can be viewed as an extension of the timing estimator based on the square law nonlinearity. For continuous phase modulations (CPM), we propose two novel estimators that can operate at the symbol rate for MSK type signals. Among the class of NDA feedforward timing estimators we are not aware of any other estimator that can function at symbol rate for this type of signals. We also propose several new estimators for the MSK modulation scheme which operate with reduced sampling rate and are robust to carrier frequency offset and phase offset

Joint Phase and Timing Recovery with CPM Signals

We describe an algorithm for joint timing and carrier phase recovery with CPM signaling. The proposed method may be employed with any CPM format and with either full or reduced state detectors. It can be implemented in digital form with a limited computational complexity. Simulation results show that its tracking performance is excellent. However, when operated in its simplest form, it may exhibit false locks during acquisition. In particular, this happens with multilevel partial response formats. A simple solution to false locks is proposed

Storia delle telecomunicazioni

Focusing on the history of scientific and technological development over recent centuries, the book is dedicated to the history of telecommunications, where Italy has always been in the vanguard, and is presented by many of the protagonists of the last half century. The book is divided into five sections. The first, dealing with the origins, starts from the scientific bases of the evolution of telecommunications in the nineteenth century (Bucci), addressing the developments of scientific thought that led to the revolution of the theory of fields (Morando), analysing the birth of the three fundamental forms of communication – telegraph (Maggi), telephone (Del Re) and radio (Falciasecca) – and ending with the contribution made by the Italian Navy to the development of telecommunications (Carulli, Pelosi, Selleri, Tiberio). The second section, on technical and scientific developments, presents the numerical processing of signals (Rocca), illustrating the genesis and metamorphosis of transmission (Pupolin, Benedetto, Mengali, Someda, Vannucchi), network packets (Marsan, Guadagni, Lenzini), photonics in telecommunications (Prati) and addresses the issue of research within the institutions (Fedi-Morello), dwelling in particular on the CSELT (Mossotto). The next section deals with the sectors of application, offering an overview of radio, television and the birth of digital cinema (Vannucchi, Visintin), military communications (Maestrini, Costamagna), the development of radar (Galati) and spatial telecommunications (Tartara, Marconicchio). Section four, on the organisation of the services and the role of industry, outlines the rise and fall of the telecommunications industries in Italy (Randi), dealing with the telecommunications infrastructures (Caroppo, Gamerro), the role of the providers in national communications (Gerarduzzi), the networks and the mobile and wireless services (Falciasecca, Ongaro) and finally taking a look towards the future from the perspective of the last fifty years (Vannucchi). The last section, dealing with training and dissemination, offers an array of food for thought: university training in telecommunications, with focus on the evolution of legislation and on the professional profiles (Roveri), social and cultural aspects (Longo and Crespellani) as well as a glance over the most important museums, collections and documentary sources for telecommunications in Italy (Lucci, Savini, Temporelli, Valotti). The book is designed to offer a compendium comprising different analytical approaches, and aims to foster an interest in technology in the new generations, in the hope of stimulating potentially innovative research