Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

Radar Cross Section (RCS) simulation of a triangular corner reflector

Altair Forum User

Hi everyone,

i'm trying to simulate a pretty simple layout for verification reasons:

The layout consists of a triangular corner reflector with the length of the inner edge to the corner of 0.5m.

I'm calculating at 5.7GHz and search for the Radar Cross Section (RCS).

In order to calculate the RCS I've added a plane wave along the X-Axis and a Far Field Request with varying configurations (which all returned the same result).

The RCS seems to be (according to Feko) roughly 82m², but the Formula i've been using has been giving me 94m² which is closer to what we've measured (a bit more than 100m² at boresight).

σ =	4·π·a⁴	where	a = Length of the side edges of the three isosceles triangles λ = wavelength of scanning Radar	(7)

	3·λ²

(Source: http://www.radartutorial.eu/17.bauteile/bt47.en.html)

Am i making any fundamental mistakes in my calculations or simulations?

Greetings

Cupacoffee

<?xml version="1.0" encoding="UTF-8"?>

Find more posts tagged with

English

Feko

Accepted answers

All comments

JIF

Hello Cupacoffee,

Do you mind adding your model? I know it is easy for me to re-create, but if you add it, I don't have to. ;-)

Johan_Huysamen

Hi Cupacoffee

I believe that the corner reflector as described in your reference should have 90 degree internal angles. Your screen shot from CADFEKO does not appear to show 90 degree angles.

You should check to ensure that this geometry is correct.

Altair Forum User

Hello Cupacoffee,

Do you mind adding your model? I know it is easy for me to re-create, but if you add it, I don't have to. ;-)

I've uploaded the model. Thanks for looking into the issue.

Hi Cupacoffee

I believe that the corner reflector as described in your reference should have 90 degree internal angles. Your screen shot from CADFEKO does not appear to show 90 degree angles.

You should check to ensure that this geometry is correct.

As can be seen in the screenshot all inner angles appear to be 90°, you can verify with the model aswell.

Greetings

Cupacoffee

<?xml version="1.0" encoding="UTF-8"?>

Unable to find an attachment - read this blog

Altair Forum User

I've figured out the source of the problem myself: The boresight of the Reflector was not aligned properly as can be seen in the screenshot.

I had a ~ 10° offset which explains the low value. The new value of 102.5m nicely lines up with the measurements we conducted.

Thanks to everyone who looked into the issue.

<?xml version="1.0" encoding="UTF-8"?>

Eric Neumann

I've figured out the source of the problem myself: The boresight of the Reflector was not aligned properly as can be seen in the screenshot.

I had a ~ 10° offset which explains the low value. The new value of 102.5m nicely lines up with the measurements we conducted.

Thanks to everyone who looked into the issue.

<?xml version="1.0" encoding="UTF-8"?>

Hello Altair Forum User,

can you tell me which value you changed to 102.5m to achieve the correct boresight? Did you rotate the whole thing?

Thanks in advance