Follow up on beam patterns

[Electronics4you]

Hi There,

I just need an answer on a very simple (not to me) question.
What does the x-axis of this beam pattern represent? Lenght, time...?

 

[Nigel Goodwin]

There's isn't really an x-axis, just a y-axis and an angular value. As the y-axis rotates 90 degrees it appears where the x-axis would be on a normal graph. The graph should really show 180 degrees, and not just 90 degrees.

 

[Electronics4you]

Ok, but the 1', 2'... must mean something, normally it would be the signal power in dB

 

[Nigel Goodwin]

Ok, but the 1', 2'... must mean something, normally it would be the signal power in dB

Could be power, could be distance - pretty much the same thing anyway.

 

[JimB]

For a graph like this, it is probably best not to think of it having an "x-axis".

This is a "polar plot", where something is plotted against an angle.
The "x-axis" is just the scaling of the radial rings.

But what that scaling is, is a bit vague.

The notation 1', 2', 3' etc infers a distance measurment in feet.
Maybe the distance from the source which gives some signal strength.

Vague and ambiguous is my best description for it.

JimB