It helped me a lot to remember that every antenna is, at its heart, a dipole. If your radials are above horizontal (less than 90 degrees to the vertical element), then you’re adding capacitance and making it tune high. Since you’re getting good SWR in that position, that suggests the antenna is too long. Your vertical element is likely fine, so I’d look at that 1CM. That’s a lot on a gigahertz antenna. I don’t know what is “correct” on your antenna design, but that’s what this hobby is all about…experimenting. I’d try shortening the radials and seeing what happens.
As for radiation pattern, you’ll get the most horizontal pattern with a true vertical dipole like you see on a lot of commercial masts. SWR is not efficiency; you can get good SWR on terrible antennas. With the elevated radials, it might tune but it will have lousy efficiency and a poor pattern. It’s best to make it the shape you know it should be (radials around 30-60 degrees down from horizontal and adjust lengths from there. How bad is the SWR in that position right now?
It helped me a lot to remember that every antenna is, at its heart, a dipole. If your radials are above horizontal (less than 90 degrees to the vertical element), then you’re adding capacitance and making it tune high. Since you’re getting good SWR in that position, that suggests the antenna is too long. Your vertical element is likely fine, so I’d look at that 1CM. That’s a lot on a gigahertz antenna. I don’t know what is “correct” on your antenna design, but that’s what this hobby is all about…experimenting. I’d try shortening the radials and seeing what happens.
As for radiation pattern, you’ll get the most horizontal pattern with a true vertical dipole like you see on a lot of commercial masts. SWR is not efficiency; you can get good SWR on terrible antennas. With the elevated radials, it might tune but it will have lousy efficiency and a poor pattern. It’s best to make it the shape you know it should be (radials around 30-60 degrees down from horizontal and adjust lengths from there. How bad is the SWR in that position right now?