We know subspace sensors are faster than light, they have to be to get real time information in certain instances, such as Voyager scanning for human DNA 9 light years away to find their recently abducted crew. But there are weird outliers such as the Picard maneuver which only works with slower than light sensors, and at least one instance in DS9 where a rotating EM pulse is used to disrupt Starfleet's sensors. Electromagnetism shouldn't disrupt subspace sensors any more than shining a bright flashlight at a telephone cable would. Does it stand to reason short range sensors are slower than light, and long range sensors are faster than light, and that they overlap depending on what action the ship is taking? For instance, in combat passive slower than light sensors would only be useful out to a few fractions of a light second before lag becomes too long, active slower than light sensors would have half the range. For navigation, slower than light sensors can be useful out to light minutes or light hours. However, I can see system confusion being created by having conflicting slower and faster than light sensor information overlapping during the Picard maneuver. The short range sensors show two targets, the long show one, and since all the information is credible the system gets confused. Has there been any indication they do not use radar? That could mean their short range sensors are purely passive.