Threats to GPS from Land-Based Signal Boosters Spectrum Space
Invaders We’ve all had voyages that weren’t quite what we signed
up for when we first got into boating—trips in which the wind
and sea on the nose have made passagemaking quite a bit
slower—and less fun—than it’s meant to be, and when rain has
reduced the passing scenery to intermittent glimpses of a gray
smudge. But suppose, just when the first sight of harbor lights
promises the reward of shore power, showers, and a decent
meal—your plotter loses its fix. Wouldn’t that just put the
cherry on it? That could become absolutely standard if one
particular company has its way. Offshore, GPS would still work
just fine. But a few miles off the coast, you’d start to lose a
lock on satellites. And for the last couple of miles into a
harbor approach, canny captains would bank on being without GPS
altogether, as powerful ground-based transmitters drown out the
faint signals from GPS satellites. The company behind this
nationwide jamming project—now known as