Transmission Lines And Electromagnetic Waves Nptel -

At low frequencies (e.g., 50 Hz or 60 Hz power lines), the physical length of a wire is negligible compared to the wavelength of the signal. In such cases, Kirchhoff’s voltage and current laws (KVL and KCL) work perfectly. However, as frequencies increase into the radio frequency (RF) range (e.g., 100 MHz and above), the wavelength becomes comparable to the size of the conductors. Suddenly, voltage and current are not the same at every point on the wire.

(IIT Bombay): A highly regarded 60-lecture series covering the entire spectrum from basic transmission line equations to antennas. Transmission Lines and Electromagnetic Waves Prof. Ananth Krishnan transmission lines and electromagnetic waves nptel

This shift demands a new framework. A (e.g., coaxial cable, microstrip, twin-lead) is not just a "wire" anymore; it is a distributed network of inductance, capacitance, resistance, and conductance. Electromagnetic waves do not simply "flow" through wires; they propagate in the dielectric medium between conductors. At low frequencies (e

The course serves as the bridge between these two worlds. It translates the abstract field concepts into practical circuit parameters, allowing engineers to design efficient communication systems, high-speed PCBs, and antenna arrays. Suddenly, voltage and current are not the same