We were using the antenna SR4G053 (with the eval board) in horizontal position and things were looked good. The reference ground plane is parallel to earth's surface and donut is actually vertical.
When we tried to use the antenna in a vertical position, the performance was very bad (relative to a dipole). Basically the donut is now horizontal with the null pointed towards the sky (similar to a dipole antenna pattern). Can you please help us in case we are missing anything? Since the eval. board's ground plane is now perpendicular to earth's reference plane, does it impact anything negatively?
Thanks very much!