Maxim has many documents showing what components to use for Power over Coax (PoC aka Phantom Power). For customers who want to design their own circuit, here are guidelines.
GMSL1 parts use a forward (video plus control) channel from 10MHz to 1.6GHz, and a reverse control channel at about 800kHz.
Design a filter with impedance >500 ohms (10x the 50 ohm impedance of the coax), from 800kHz to 1.5GHz. This typically requires 100uH, 4.7uH and 330nH in series. A high inductance ferrite can replace the 4.7uH and 330nH inductors.
the 100uH inductor can be 47uH if the reverse control channel is set for fast (REV_FAST), High Immunity Mode (HIM).
Make sure inductors are rated for the system current.
Model the filter using RLC models for inductors. Make sure the response is flat within a few 10's of ohms, by using fairly low Q inductors with ~2K resistors across them.