Rectangular Waveguide Field in Polar Coordinates

AI Thread Summary
The discussion revolves around converting the electric and magnetic field components of a rectangular waveguide from Cartesian coordinates (Ex, Ey, Hx, Hy) to polar coordinates (Er, Eθ). The original poster, Gareth, sought assistance after successfully converting circular waveguide fields in the opposite direction. A suggestion was made to solve the linear equations for Er and Eθ directly. Ultimately, Gareth resolved the issue independently by correctly mapping the vectors. The conversation highlights the process of coordinate transformation in waveguide analysis.
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Hi, I have the fields for a rectangular waveguide in terms of cartesian components, that is, Ex, Ey, Hx, Hy. I need to convert these to polar components in terms of r and theta.

I've done this the other way around, converted a circular waveguide field which was written in terms of r and theta to the cartesian components by Ex=Er*cos(theta)-Etheta*sin(theta) and Ey=Er*sin(theta)+Etheta*sin(theta).

Can anyone help convert the cartesian components of the rectangular waveguide into polar components in a similar way?

Thanks,
Gareth
 
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You could just solve the equations you have for E_r and E_\theta - they're linear equations, so it'll be easy ;-)
 
diazona said:
You could just solve the equations you have for E_r and E_\theta - they're linear equations, so it'll be easy ;-)


Thanks, actually I've figured it out. It was just a question of mapping the vectors in the right direction!
 
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