Rectangular Waveguide Excitation

Hi to all,
I need to excitate a rectangular waveguide employing a planar microstrip structure.
The problem is that I need to insert the planar microstrip PCB parallel to the h-plane of the waveguide.
I have found some papers which employ a vivaldi or slot microstrip antenna in order to excitate the Te10 mode of the rectangular waveguide but these microstirp PCB are parallel to the E-plane instead of the h-plane.

Can anyone help me?
Thank you so much in advance.

check these it is helpful

http://www.prof-robertson.com/index_...MICROSTRIP.pdf
Transition between a rectangular waveguide and a microstrip line comprised of a single metallized bar
http://www3.imperial.ac.uk/pls/porta...1/34469698.PDF

http://www.empire.de/main/Empire/pdf.../ws_ap2000.pdf