Applications
High gain antennas are typically the largest component of deep space probes, and the highest gain radio antennas are physically enormous structures, such as the Arecibo Observatory. The Deep Space Network uses 35 meter dishes at about 1 cm wavelengths. This combination gives the antenna gain of about 100,000,000 (or 80 db, as normally measured), making the transmitter appear about 100 million times stronger, and a receiver about 100 million times more sensitive, provided the target is within the beam. This beam can cover at most 1/100 millionth of the sky, so very accurate pointing is required.
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