Technical possibility of a pure "listener"/passive version?

[tobiasfalk]

Hi, I am not in any way remotely capable enough to use understand this in detail but still had one maybe weard question?

What about creating a pure passive version that does not send out a signal to be reflected but purely listens.
With additionally knowing the position of multiple(3min) of such stations, that know that they received a signal from the same source, one could also build a "map".
An other possibility that itbwould bring, is that if also the location of the source is know things that do not reflect directly back could also be "seen".

As said not that much technically advanced in this field, so not sure if there are things missing or to complicated to implement that.

Some things that come to my mind for implementing that would be required are:

• accurate time synchronisation between the stations
• accurate position of the stations, not sure if "normal" GPS/GNSS is enough or if more advanced strategies like phone tower triangulation and more is needed.
• Signal modulation, for the later descripte case, maybe some way to "identify" from which source it came by adding a id as modulation to the signal. Would add the possibility of having multiple sources and differentiation between them.

[NawfalMotii79]

@tobiasfalk I'm working for the moment on a Passive RADAR for ships.
Functional_Diagram_REV_A.pdf