... magnetic sensor for senses 0.1 to 3 Hz noise signal. However, they use not only a high-input impedance amplifier with feedback but also a shunt resistor increases the noise significantly and is used in applications where the noise is not a primary concern. In their case, noise measurements are not e ...
Mathematics of radio engineering
The mathematics of radio engineering is the mathematical description by complex analysis of the electromagnetic theory applied to radio. Waves have been studied since ancient times and many different techniques have developed of which the most useful idea is the superposition principle which apply to radio waves. The Huygen's principle, which says that each wavefront creates an infinite number of new wavefronts that can be added, is the base for this analysis.