The satellite says +15% Science in cities in range. Short answer: It provides extra science to cities not tiles.
If the city is working tiles that yield science, the satellite is technically affecting tiles indirectly in the sense that its multiplying the Science of the city which may be working the tile. But the Lasercom Satellite does not function like the Solar Collector where it make the tiles have more energy on them.
If I'm not mistaken, you can fit 2 cities under 1 satellite if you have the correct spacing.