Proceedings Of The Ire

Phase-Locked Loops for Wireless Communications: Digitial, Analog and Optical Implementations, Second Edition presents a complete tutorial of phase-locked loops from analog implementations to digital and optical designs. The text establishes a thorough foundation of continuous-time analysis techniques and maintains a consistent notation as discrete-time and non-uniform sampling are presented. New to this edition is a complete treatment of charge pumps and the complementary sequential phase detector. Another important change is the increased use of MATLAB®, implemented to provide more familiar graphics and reader-derived phase-locked loop simulation. Frequency synthesizers and digital divider analysis/techniques have been added to this second edition. Perhaps most distinctive is the chapter on optical phase-locked loops that begins with sections discussing components such as lasers and photodetectors and finishing with homodyne and heterodyne loops. Starting with a historical overview, presenting analog, digital, and optical PLLs, discussing phase noise analysis, and including circuits/algorithms for data synchronization, this volume contains new techniques being used in this field. Highlights of the Second Edition: Development of phase-locked loops from analog to digital and optical, with consistent notation throughout; Expanded coverage of the loop filters used to design second and third order PLLs; Design examples on delay-locked loops used to synchronize circuits on CPUs and ASICS; New material on digital dividers that dominate a frequency synthesizer's noise floor. Techniques to analytically estimate the phase noise of a divider; Presentation of optical phase-locked loops with primers on the optical components and fundamentals of optical mixing; Section on automatic frequency control to provide frequency-locking of the lasers instead of phase-locking; Presentation of charge pumps, counters, and delay-locked loops. The Second Edition includes the essential topics needed by wireless, optics, and the traditional phase-locked loop specialists to design circuits and software algorithms. All of the material has been updated throughout the book.

Analytical techniques presented thus far for treatment of unequally spaced antenna arrays have pointed out that desirable radiation characteristics can be achieved using only the interelement spacings as design parameters. The advantage is that the excitation amplitudes required can be either uniform or nearly uniform across the array, thereby allowing use of a simple feed system for excitation of the array elements and minimizing adverse mutual coupling effects. The design methods have found only limited applications, however, since results are not always reliable due to the approximations necessary to simplify the analytical work. Various computational methods have been presented to circumvent this problem, but these in turn suffer disadvantage in that they provide no control over the ultimate positions of the array elements, giving rise to unrealistic spacing configurations and severe realization problems through mutual coupling. In this work a new computational technique is presented for designing unequally spaced arrays. The method is particularly suitable for use with modern high-speed electronic computers, and allows certain practical restrictions or constraints to be included in the design procedure by allowing use of a limited number of different excitation amplitude levels. The result in any given example is an unequally spaced linear array designed for a specified sidelobe level, with a number of amplitude levels appropriate for insuring that prespecified spacing restrictions are met. Thus, the practical difficulties encountered with the results of other computational schemes are largely avoided. Several examples are given, and both theoretical and experimental results are included. (Author).

Precision Measurement of Microwave Comprehensive resource covering the foundations and analysis of precision noise measurements with a detailed treatment of their uncertainties Precision Measurement of Microwave Thermal Noise presents the basics of precise measurements of thermal noise at microwave frequencies and guides readers through how to evaluate the uncertainties in such measurement. The focus is on measurement methods used at the U.S. National Institute of Standards and Technology (NIST), but the general principles and methods are useful in a wide range of applications. Readers will learn how to perform accurate microwave noise measurements using the respected author’s expertise of calculations to aid understanding of the challenges and solutions. The text covers the background required for the analysis of the measurements and the standards employed to calibrate radiofrequency and microwave radiometers. It also covers measurements of noise temperature (power) and the noise characteristics of amplifiers and transistors. In addition to the usual room-temperature two-port devices, cryogenic devices and multiport amplifiers are also discussed. Finally, the connection of these lab-based measurements to remote-sensing measurement (especially from space) is considered, and possible contributions of the lab-based measurements to remote-sensing applications are discussed. Specific topics and concepts covered in the text include: Noise-temperature standards, covering ambient standards, hot (oven) standards, cryogenic standards, and other standards and noise sources Amplifier noise, covering definition of noise parameters, measurement of noise parameters, uncertainty analysis for noise-parameter measurements, and simulations and strategies On-wafer noise measurements, covering on-wafer microwave formalism, noise temperature, on-wafer noise-parameter measurements, and uncertainties Multiport amplifiers, covering formalism and noise matrix, definition of noise figure for multiports, and degradation of signal-to-noise ratio Containing some introductory material, Precision Measurement of Microwave Thermal Noise is an invaluable resource on the subject for advanced students and all professionals working in (or entering) the field of microwave noise measurements, be it in a standards lab, a commercial lab, or academic research.

First demonstrated in 1928, color television remained little more than a novelty for decades as the industry struggled with the considerable technical, regulatory, commercial, and cultural complications posed by the medium. Only fully adopted by all three networks in the 1960s, color television was imagined as a new way of seeing that was distinct from both monochrome television and other forms of color media. It also inspired compelling popular, scientific, and industry conversations about the use and meaning of color and its effects on emotions, vision, and desire. In Bright Signals Susan Murray traces these wide-ranging debates within and beyond the television industry, positioning the story of color television, which was replete with false starts, failure, and ingenuity, as central to the broader history of twentieth-century visual culture. In so doing, she shows how color television disrupted and reframed the very idea of television while it simultaneously revealed the tensions about technology's relationship to consumerism, human sight, and the natural world.