Communications (Cont.)
•For Deep Space Communications NASA uses both the TDRS satellites as well as Earth based Antennas pictured below for communications with distant spacecraft and rovers. •The below picture is a 70m antenna in Goldstone, Cali. This is one of many antennas that communicate with the Voyager probes and the Mar’s spacecraft and Rovers. •A common system at Mars is to relay signals from Goldstone and then to MRO/MTO and then its relayed to the Rovers.
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70 Meter Antenna at Goldstone Deep Space Communications Complex
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MRO Relaying Signal to Mars Rovers
The Voyager spacecraft use a 23-watt radio transmitter. This is far higher than the 3 watts a typical cell phone uses for comparison.

That signal, produced by a 23-watt radio transmitter, is so faint that the amount of power reaching Earth antennas is 20 billion times smaller than the power of a digital watch battery.

That’s: 0.00000000115 of a Watt

How do we receive such a weak signal from the edge/outside our solar system from Voyager:
-Directional antennas that point right at each other
-Radio frequencies without a lot of man-made interference on them
-Very large antennas

The Voyager satellites are also transmitting in the 8 GHz range, and there is not a lot of interference compared to other more commonly used frequencies.