Oh boy. What a strange article. While they try to explain all intricate details, their funny use of analogies turns most things they tell either wrong or at lea

Oh boy. What a strange article. While they try to explain all intricate details, their funny use of analogies turns most things they tell either wrong or at least wildly off the mark. A GPS receiver only receives at a single frequency (leaving out doppler for now) but correlates several pseudorandom codes in simultaneously. It needs four sattelites no to increase the accuracy, but to solve for the fourth unknown, time. Also it doesn't use a quartz clock that resets "lets say at midnight" but measures the relative state of it's correlators' counters (that's what's often called "pseudorange"). And DGPS doesn't correct for incorrectly sent out almanacs. It only corrects for unknown propagation properties of our atmosphere (rather oddly described as slowing down of electromagnetic energy). DGPS also doesn't help you with multipath reception due to reflections at skyscrapers.