Why mobile phones are banned inside planes
Did you think you weren’t able to call people on board a plane because your phone was interfering with the weird stuff inside the cockpit? Think again.
Excellent article on The Economist’s tech blog, Babbage:
Intentional transmitters, like mobile phones, two-way pagers and walkie-talkies, present a different sort of problem. With these, engineers worry about the so-called “near-far” effect. Even if below permitted levels, any spurious emissions they might produce would occur close to an aircraft’s avionics, compared with the weak signal from a ground-based radio beacon hundreds of kilometres away, or the whispers from a GPS satellite thousands of kilometres up in space. The concern here is that weak, distant signals might be drowned out as a navigation receiver captures a spurious signal that may also be weak but is significantly closer.