b. When fading is of the inverse-bending type, space diversity ordinarily is not helpful, unless
the second antenna can be placed considerably above the original antenna.
c. Fading effects are not completely eliminated by the use of space diversity, but the duration of
poor signal-to-noise ratio is considerably reduced.
d. The diversity antenna usually is placed from 50 to 100 feet directly below or above the first
receiving antenna (figure 19). Only a rough practical rule can be used, so considerable changes in
antenna spacing may be necessary. Spacing of even less than 50 feet may be effective. Frequency
diversity may also be used to minimize fading on microwave systems.
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