This module will equip the student with a sound understanding of the problems caused by noise in electrical networks. Both fundamental and man-made noise are discussed. Techniques to minimise noise are discussed.

Fundamental Noise: Noise mechanisms in electronic components. Summation of noise signals, noise spectral density, noise summation in a band, noise bandwidth for common ?lters. Ampli?er Noise: Representation of noise in ampli?ers, equivalent input noise voltage and its equivalent input current and voltage sources. Noise Figure. Semiconductor Noise: BJT noise model, noise in JFETs and MOSFETs. Low Noise Ampli?ers: Design. Methods of noise and noise ?gure measurement. Man- Made Noise: European regulations, EMI emissions, EMI susceptability, conducted and radiated noise. Noise From PCBs: Track structures: strip line, microstrip and single sided board. Calculation of capacitive and inductive coupling between tracks as well as radiation from pcb tracks. Power Line Noise: Noise on power supply lines and its minimisation. Power supply ?lters for minimisation of conducted noise, both common and differential mode. Shielding: Effectiveness as function of frequency, shield thickness, conductivity and permeability. Effectiveness to inductive and radiated ?elds.

List the various sources of noise in an electronic system. Analyze the contributions of various noise sources to the overall noise figure of an electronic system. Design low-noise amplifier systems using BJTs, JFETs and MOSFETs. Design low-noise PCBs. Design filters to reduce the effects of power-line noise. Analyze the effectiveness of shielding structures.

Appreciate the regulatory framework governing EM emissions from electronic/electrical systems.

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Lectures/Labs