Antenna - Theory .com: The Antenna Site

Antenna Basics Antenna Types Smith Charts Antenna Measurements

antenna-theory.com :: View topic - Converting 2D angles to solid angles
antenna-theory.com Forum Index antenna-theory.com
Antenna Theory
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Converting 2D angles to solid angles

 
Post new topic   Reply to topic    antenna-theory.com Forum Index -> Questions Related to Antenna Theory
View previous topic :: View next topic  
Author Message
Mszazynski
Antenna-Theory.com Newbie


Joined: 26 Dec 2017
Posts: 6

PostPosted: Fri Dec 29, 2017 5:40 pm    Post subject: Converting 2D angles to solid angles Reply with quote

If I know the beamwidth of my main beam is 2 degrees in the azimuthal and 2 degrees in elevation, how can I determine what solid angle this would create? This article essentially says that the number of steradians in your solid angle would be equal to:

(Max_Azimuth-Min_Azimuth)*[sin(Max_Elevation)-Sin(Min_Elevation)]

https://math.stackexchange.com/questions/1243540/how-to-calculate-the-solid-angle-of-a-spherical-rectangle-from-astronomical-angl

Would you say this is accurate? Is there a better way?
Back to top
View user's profile Send private message
e.fannio
Antenna Theory Regular


Joined: 12 Jul 2018
Posts: 10
Location: Naples, Italy

PostPosted: Thu Jul 12, 2018 8:22 pm    Post subject: Re: Converting 2D angles to solid angles Reply with quote

Mszazynski wrote:
If I know the beamwidth of my main beam is 2 degrees in the azimuthal and 2 degrees in elevation, how can I determine what solid angle this would create? This article essentially says that the number of steradians in your solid angle would be equal to:

(Max_Azimuth-Min_Azimuth)*[sin(Max_Elevation)-Sin(Min_Elevation)]

https://math.stackexchange.com/questions/1243540/how-to-calculate-the-solid-angle-of-a-spherical-rectangle-from-astronomical-angl

Would you say this is accurate? Is there a better way?


The right formula should be Omega = (Max_az - Min_az)*[cos(min_el) - cos(max_el)]
Here is the demonstration
Back to top
View user's profile Send private message
admin
Site Admin


Joined: 03 Jan 2007
Posts: 210

PostPosted: Thu Jul 12, 2018 9:26 pm    Post subject: Reply with quote

Yes great proof

both answers are correct though....if you define elevation as angle above horizon

e.fannio note you are using standard polar coordinates with uses angle measured off z-axis, hence the reason for change between sin and cos
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    antenna-theory.com Forum Index -> Questions Related to Antenna Theory All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group