Well done Tikiarya.
My standard patch antenna is a good antenna but clearly it is time to explore a lot more antenna designs for our exciting L-Band experiment.
looks great, how big is it?
The helix looks beautiful! A built one for AERO frequency a year ago and it worked good. But I noticed most of the designs stressed the last quarter turn or so should be very close to the ground plane to achieve a better match to the 50 ohms of the receiver. Your helix may be fine the way it is.
Looks nice, but looks aren’t everything
The question is, how does it compare to the air-gap patch? Actual SNR Measurements please.
As noted by @donde, the last quarter turn is supposed to be close to the ground plane so the impedence matches 50 ohms. From the photo, there is a very large gap between the last turn and the ground plane.
If it works, please publish the SNR of your antenna vs. Outernet’s air gap patch.
Can you include VNA or actual operational SNR plots of the antenna? What S11 value have you seen on your instrument?