# How is the magnetic field radiated in a microstrip patch antenna?

If we talk about dipoles or any other antenna, we discuss the electric field as well as the magnetic field. But while discussing micro-strip antennas, only the electric field is explained.

Why?

EM waves are made of both fields and antennas radiate both fields.

This is because the square root of the ratio of the permeability of free space to permittivity of free space is 377 or $$\\sqrt{\dfrac{\mu_0}{\epsilon_0}}\$$. This is naturally called the impedance of free space.
Knowing that $$\\mu_0\$$ is in henries per metre and that $$\\epsilon_0\$$ is in farads per metre, the equation for impedance can be re-written as $$\\sqrt{\dfrac{L}{C}}\$$ because the "per metre" parts cancel. This is of course is the characteristic impedance of a lossless transmission line.