- #1

- 20

- 0

## Homework Statement

This is a statement i found in one of my textbook of "Antenna analysis".

The phase front of a exponential time varying quantity(charge distribution) 'e

^{jwt}' is a spherical wave front and is represented by e

^{-jkR}.

## Homework Equations

1. How can we represent spherical wavefront as e

^{-jkR}for a quantity exponential time variation e

^{jwt}?

2. Does the term wt have a physical meaning?

## The Attempt at a Solution

Please look into my attempt from the beginning and correct me if I am wrong anywhere.

Consider a complex quantity e

^{jwt}= cos wt + j sin wt.

Re{e

^{jwt}} = cos wt

Im{e

^{jwt}} = sin wt

Now, if we plot this quantity with one axis as real axis i.e., cos wt and other axis as imaginary axis i.e., sin wt. Then we obtain a circle for different values of wt.

Is this the circle we that is the constant phase spherical wavefront of e

^{jwt}. But in this circle actually the phase wt does vary which is how we obtain the circle.

How do we relate this circle to e

^{-jkR}?