DIGITAL ENCODING OF TELEVISION SIGNALS USING THE PULSE WIDTH MODULATOR

An attempt is made to quantify the circuit complexity and mean circuit speed of linearly quantized straight PCM video encoding techniques. Any significant reduction in circuit complexity (i.e. the number of active and passive devices to be integrated) is considered important since this determines: chip area and yield if the encoder is to be fully integrated. Analysis indicates that the complexity of the more highly developed straight PCM video encoders can be reduced by typically a factor 3 using either non-programmed sequential encoding, pulse width modulator encoding or programmed sequential encoding (closed loop successive approximation). The encoder studied in this work is an 8-bit pulse width modulator video encoder using a 2-step production line technique and a detailed design procedure for a prototype encoder is given. This encoder is considered to achieve 7-bit resolution at a sampling rate of 13.3MHZ. A mathematical model of the encoder-decoder system is developed for numerical evaluation of the effect of encoder errors and white Gaussian noise upon a coded and decoded video signal. A triangular wave test is applied to examine the effect of encoder errors upon the statio transfer characteristic of the encoder. Dynamic errors are investigated by simulating colour subcarrier at the model input and observing the phase and gain errors at the filtered codec output. Using differential phase and gain, an attempt is made to determine a circuit design and alignment criterion such that most practical codecs will fall within specific bounds on these parameters (taken as ±6° and ±6% respective1y). In the absense of dither, Monte Carlo analysis indicates that the maximum voltage error incurred by each encoder error source should have a high probability (95%) of being less than a half quantum if 85 - 90% of codecs measured are to fall within the above bounds. If white Gaussian noise is used as a simple dither signal then the probability of a codec falling within the above bounds may increase to about 95%. Improvements to the encoder are discussed, including several automatic error correction techniques which combat instrumental errors and give a more robust PWM encoder. Also, by predetermining the most significant bit for each set of 4 coded bits it is possible to halve the encoder clock frequency (to 133MHZ) without significantly changing the encoder complexity

Integrated Circuits/Microchips

With the world marching inexorably towards the fourth industrial revolution (IR 4.0), one is now embracing lives with artificial intelligence (AI), the Internet of Things (IoTs), virtual reality (VR) and 5G technology. Wherever we are, whatever we are doing, there are electronic devices that we rely indispensably on. While some of these technologies, such as those fueled with smart, autonomous systems, are seemingly precocious; others have existed for quite a while. These devices range from simple home appliances, entertainment media to complex aeronautical instruments. Clearly, the daily lives of mankind today are interwoven seamlessly with electronics. Surprising as it may seem, the cornerstone that empowers these electronic devices is nothing more than a mere diminutive semiconductor cube block. More colloquially referred to as the Very-Large-Scale-Integration (VLSI) chip or an integrated circuit (IC) chip or simply a microchip, this semiconductor cube block, approximately the size of a grain of rice, is composed of millions to billions of transistors. The transistors are interconnected in such a way that allows electrical circuitries for certain applications to be realized. Some of these chips serve specific permanent applications and are known as Application Specific Integrated Circuits (ASICS); while, others are computing processors which could be programmed for diverse applications. The computer processor, together with its supporting hardware and user interfaces, is known as an embedded system.In this book, a variety of topics related to microchips are extensively illustrated. The topics encompass the physics of the microchip device, as well as its design methods and applications

Study of efficient transmission and reception of image-type data using millimeter waves

Evaluation of signal processing and modulation techniques for transmission and reception of image type data via millimeter wave relay satellite

Cumulative Index to NASA Tech Briefs, 1963 - 1966

Cumulative index of NASA Tech Briefs dealing with electrical and electronic, physical science and energy sources, materials and chemistry, life science, and mechanical innovation

Disseny microelectrnic de circuits discriminadors de polsos pel detector LHCb

The aim of this thesis is to present a solution for implementing the front end system of the Scintillator Pad Detector (SPD) of the calorimeter system of the LHCb experiment that will start in 2008 at the Large Hadron Collider (LHC) at CERN. The requirements of this specific system are discussed and an integrated solution is presented, both at system and circuit level. We also report some methodological achievements. In first place, a method to study the PSRR (and any transfer function) in fully differential circuits taking into account the effect of parameter mismatch is proposed. Concerning noise analysis, a method to study time variant circuits in the frequency domain is presented and justified. This would open the possibility to study the effect of 1/f noise in time variants circuits. In addition, it will be shown that the architecture developed for this system is a general solution for front ends in high luminosity experiments that must be operated with no dead time and must be robust against ballistic deficit