I plead ignorance. When using an external antenna, such as with the Reach M+, how do you determine the GPS antenna height? When the GPS signal hits the antenna, it has to travel down the antenna feed to the detector circuitry in the M+. So assume the “antenna” height I should be using with my PPK workflow is actually the distance my antenna is above my camera…MINUS the length of cable between the antenna and the M+? In my case, that puts the effective antenna height below the camera.
You can consider the antenna height to be the base of your GNSS antenna. I assume you are using the typical Emlid-provided antenna for your M+.
If you want your position solution to be at the camera height instead of the antenna height, then use the distance between the two and enter it as a positive number.
The cable length does not factor in to this calculation.
Ok, I think I understand. The antenna is the observation point through which signals are compared. The PRNs are aligned based on what was observed at the antenna. The length of cable between the antenna and detector would effect the detector’s time accuracy, but not the process of trilateralization.
