I need to convert a polar plot into a short array of 3-5 values. This array should describe the polar plot as best as possible.

For example, I know that I can use the beamwidth which is also known as the half power. This is the angle between the left and right -3 dB point:

Visual concept of beamwidth

I also know that I can use the the ratio between the surface of the polar plot versus the whole 360° plane.

Thus, so long I only have two values in the array:

  • Beamwidth
  • Ratio polar plot vs plane

But are there other values that can describe the polar plot ? And also, how can I have a value which describes second biggest lobe ?


migrated from math.stackexchange.com Nov 11 '16 at 21:18

This question came from our site for people studying math at any level and professionals in related fields.

  • 2
    $\begingroup$ I asked a DSP moderator for an opinion, all in the interest of saving time. $\endgroup$ – Jyrki Lahtonen Nov 1 '16 at 10:57

Some examples would be the null to null bandwidth(s) as well as the sidelobe levels of the first/second sidelobes.

Example vector of 5 numbers: [mainlobe gain, first null location, 1st sidelobe gain, second null, 2nd sidelobe gain]

From this you could produce an estimate for the 3 dB points of each lobe using some "reasonable" formula, i.e. halfway between the peak and the null.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.