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Data Hacking

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This sequence is summarized in Figure 4-13.<br />

Signal reradiated to<br />

GPS receiver<br />

Chapter 4 — Antenna Hacks<br />

FIGURE 4-13: Reradiating antennas catch and retransmit the signals received from the GPS<br />

satellites.<br />

There are two types of reradiating antenna:<br />

Personal reradiating antenna<br />

Communal reradiating antenna<br />

Remember that a reradiating antenna can only pick up satellites that are above the horizon and<br />

not obscured by buildings or rock faces. Reradiating antennas can’t perform the impossible, they<br />

are just able to make better use of the existing signal.<br />

Personal Reradiating Antenna<br />

Signal received<br />

from satellites<br />

Personal reradiating antennas have a short-range reradiator that can re-transmit the GPS signal<br />

over a relatively short distance (between 40 and 60 centimeters). The reradiator is usually<br />

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