Slotted Waveguide Antenna

Hello,

I see that slotted waveguide antennas are usually built from elements with diagonal offset (as shown in attached figure).
The longitudinal offset is understood to me (phase difference), however the horizontal offset is not clear.

If the waveguide is excited by TE 10 fundamental mode, the E field keeps his sign along X axis.

Can you please help me figuring out? Does the horizontal offset also has something to do with the accumulated phase?


Thank you

Longitudinal offset is 180°. Check this (page 7): https://www.qsl.net/n1bwt/ch7_part1.pdf
Here is another useful explanation:
http://www.ecs.umass.edu/mie/labs/md...r/anlysis1.htm
note how sign is changed for fields (red to blue)

Slotted waveguide antennas can often be very useful. The basic idea is that in moving the slots around the amplitude and phase distribution of an array can be controlled. The trick is finding the appropriate placement and then figuring out how to manufacture the thing. Modern simulation tools and numeric controlled machining makes these much easier to realize. Slotted waveguides appear often in shipboard and airborne radars.

I note that there seem to be threads on the same subject here. You might fish through some of them to see if any are helpful.

Regards,

Azulykit