Objective:
- Design & construction of a high performance L-band reception antenna (e.g. for INMARSAT monitoring)
- Flexible design to allow for multiple mounting options
Design Options
| ID | Type | Design features |
| A.1 | LHCP Helix for offset dish | Mounting off center to get enough clearance towards dish arm |
| A.2 | LHCP Helix for prime focus dish | Mounting centric |
| B.1 | RHCP Helix for direct reception | Tripod mounted (or other), right hand polarization for direct reception |
Option A.1
Offset dish geometry: red lines show the nominal ray tracing from satellite into the LNB phase center.
An L-band helix including its reflector are much bigger then the standard LNBs and would thus need to be moved slightly above the nominal LNB position. This would result in the green ray tracing which would slightly delude the focus.
Helix phase center approximate sits at the lower third of the helix. Fixing the helix at the proposed positiong would result in the helix sitting too far forward. It needs to be checked if this degrades the performance no longer justifying the simplicity of such a setup. The picture below just includes an LNB for comparision. In a real setup no LNB would be present of course.
Size comparison with IceConeFeed
