Question

A 2 m long coaxial cable operates at 10 MHz. The distributed inductance and capacitance of the cable are specified as 0.215 uH/m and 48.28 pF/m, respectively. The input impedance of the cable at the sending end is measured as 50+j25 ohm. Determine the impedance of the load. The cable is assumed to be lossless.

ANSWER: 41.86 + j4.18 Ohm

Answer 1

Characterestic Impedence can be calculated as follows

For a lossless Cable R=0 and G=0

Given

Input Impedence is given by

standard Input Impedence formula for Transmitting system is

Given gamma is called as propagation constant which is a combination of Attenuation constant and Phase constant which are expressed as follows

For a lossless Line Attenuation will be zero Hence

Hence Input Impedence expression for a lossless line will be

Where Phase Constant

where Wave Length

By solving above expression we will get Load Impedence Value