Concepts Development, Organisation, Operations Specialist
I would actually suggest development of an integrated multimodal navigation system. A GPS-type satellite system (actually, a collection of such systems around all major colonised bodies) would, of course, be one component. However, I suggest that this should be augmented with a set of stationary surface transmitters; as well as integrating transmitters from spacecraft (as well as vessels and surface vehicles... as well as stationary assets) transponders that transmit their computed position. Computed positions will involve an averaging of external GPS
sources, stellar tracking, internal inertial platform tracking, and guidance commands
/manoeuvring system feedback. Each system, as part of its signal, will send a reliability code
that factors in standard deviation measurements.
In addition to position and time stamps, larger transmitors will also send sensor information of local objects, including the locations of other integrated transmitor sources. This will allow receivers with sufficient computational power to overlay multiple maps of the local neighborhood, allowing even more refinement of positioning data.
Smaller receivers will probably incorporate only signals from larger, more reliable transmission sources. These will then transmit their computed positions in response. Of course, these will be more prone to error, as would components in motion... but such error will be noted in the transmission signal.
The advantage of this is that the system can remain valid even outside the intended coverage of a given component GPS sytem; or in regions where traditional GPS signals might not be available. Furthermore, this system will aid in tracking traffic, as well as potential traffic hazards.