How does google maps knows that there is a road over this place i mean we have roads all covered with dense trees so if they use satellite’s, the satellite’s hardly can see a road from top, so how do they figure out?

Question

How does google maps knows that there is a road over this place i mean we have roads all covered with dense trees so if they use satellite’s, the satellite’s hardly can see a road from top, so how do they figure out?

In: 4

Answer 1

The map of roads is stored either in cloud servers that are accessed through the internet or locally on your device. The satellites don’t see the roads, they send out a signal that tell where they are with a timestamp. When your device gets these messages from at least 3 of those satellites, it can do some math to figure out where you are on the map it already had and can tell you where to go next. This is why bad cell reception can mess with your phone maps even though you might have a clear view of the sky; it cuts you off from the road map stored by google, apple, etc.