×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

# Corrugated horn - Radiation pattern problem...

 Forum Search FAQs Links MVPs

## Corrugated horn - Radiation pattern problem...

(OP)
The radiation pattern of a corrugated-horn is given by the function

g(θ) = P1v(cosθ)/sinθ + dP1v(cosθ)/dθ

where
P1v(cosθ)
is the associated Legendre function of the first kind and order v.

The problem is determine its order v.
I know that to find v I have to use g(θm) = 0, where θm is the max angle (horn flare angle). If θm = 20º or any other angle, how could I find the order v in a way that g(θm) = 0 ???

Someone can help me with a tip or a reference?

Thanks any help...

### RE: Corrugated horn - Radiation pattern problem...

If I understand your question (a risky assumption), then perhaps the principle of Conservation of Energy might be useful. Put another way: if the average gain over the sphere exceeds unity, then you're doing it wrong.

Is this an academic problem?

### RE: Corrugated horn - Radiation pattern problem...

(OP)
Yes, it is an academic problem.
I need to know this theoric radiation pattern then I will be able to use the principle of Conservation of Energy.
Anyway, thanks.

### RE: Corrugated horn - Radiation pattern problem...

An alternate is a brute force method to calculate the pattern, create an array of radiators that fill the aperture. Sum your radiators with vector math using voltage amplitude* e^jbndcos(theta) in Excel or MathCad.

If it's a good corrugated layout you know the amplitude in the aperture is a Cosine function and if you know the angle of the horn that provides the phase error in the aperture. Not sure if corrugations change that phase in the aperture since corrugations are a slow wave structure.

Is this to design a new horn or analyze a current horn?

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

#### Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login

#### Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a partâ€™s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!