Answer:
The reasonable value = 2.96 × 10^(-1) µW
Step-by-step explanation:
* Lets explain how to solve the problem
- A mobile base station in an urban environment has a power
measurement of 8 µW at 225 m
- The propagation follows an inverse cube power law
- We need to find the reasonable value to assume at a distance
678 m from the base station
∵ The propagation follows an inverse cube power law
- <em>The power would have been decreased by a factor 1/n³ </em>
<em> times the power as a distance increasing</em>
∵ n = the ratio between the distances
∵ The distance are 675 m and 225
∴ n = 675/225 = 3
∴ 1/n³ = 1/3³ = 1/27
- The reasonable value is the product of the power measurement of
8 µW and 1/27
∴ The reasonable value = 8 × 1/27 = 8/27 µW = 0.296296
∴ The reasonable value = 2.96 × 10^(-1) µW
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