Fixed Terrestial Wireless
From Navas Wireless Wiki
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== Path Variables == | == Path Variables == | ||
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=== Line of Sight === | === Line of Sight === | ||
If you have line of sight, then tree growth or someone building and consequently obstructing the line of sight might well create a problem. If you don't have line of sight, then the path might still work, but might change with the seasons if trees are the reason for it not being line of sight. | If you have line of sight, then tree growth or someone building and consequently obstructing the line of sight might well create a problem. If you don't have line of sight, then the path might still work, but might change with the seasons if trees are the reason for it not being line of sight. | ||
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=== Ground Reflection === | === Ground Reflection === | ||
If the path is high above ground, and crosses over a flat area along the path that can be seen from the antennas at both ends, then you have the possibility of signal reflections off the ground arriving at the receive antenna delayed and out of phase with the direct path, and the two signals can cancel. It is an unfortunate fact of life that the reflectivity of the ground can change drastically. If you have a rough surface, or a nice crop of corn, it will attenuate any signal that would otherwise be reflected. But at another time of year, the ground can be bare, maybe have a nice coating of dew or water, and be very reflective. The solution to this type of problem normally is to alter the height of one antenna and change the reflection from a cancelling mode to an additive mode. | If the path is high above ground, and crosses over a flat area along the path that can be seen from the antennas at both ends, then you have the possibility of signal reflections off the ground arriving at the receive antenna delayed and out of phase with the direct path, and the two signals can cancel. It is an unfortunate fact of life that the reflectivity of the ground can change drastically. If you have a rough surface, or a nice crop of corn, it will attenuate any signal that would otherwise be reflected. But at another time of year, the ground can be bare, maybe have a nice coating of dew or water, and be very reflective. The solution to this type of problem normally is to alter the height of one antenna and change the reflection from a cancelling mode to an additive mode. | ||
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| + | === Rain Attenuation === | ||
| + | With a radio path of less than 10 miles, the path should not normally be subject to too many variables. Rain attenuation would not normally be a problem. | ||
==Service Speeds== | ==Service Speeds== | ||
