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| {{Unreferenced|date=November 2010}}
| | The name of the author is Luther. I presently live in Alabama. The job I've been occupying for years is a bookkeeper but I've already utilized for another one. What she enjoys performing is to play croquet but she hasn't produced a dime with it.<br><br>Also visit my homepage :: auto warranty ([http://Ernrduo.Woobi.Co.kr/xe/?document_srl=582849 source for this article]) |
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| '''Lee Model for Area-to-Area Mode''' is a [[Radio propagation model]] that operates around 900 MHz. Built as two different modes, this model includes an adjustment factor that can be adjusted to make the model more flexible to different regions of propagation.
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| ==Applicable to/under conditions==
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| This model is suitable for using in data collected in a specific area. The model predicts the behaviour of all links that has ends in specific areas.
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| ==Coverage==
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| [[Frequency]]: 900 MHz Band
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| ==Mathematical formulation==
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| ===The model===
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| The Lee Model is formally expressed as:
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| <math>L \; = \; L_0 \; + \; \gamma \log d \; - 10 \log {F_A}</math>
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| where,
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| :''L'' = The [[median]] [[path loss]]. Unit: [[decibel]] (dB)
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| :''L''<sub>0</sub> = The reference [[path loss]] along 1 km. Unit: decibel] (dB)
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| :<math>\gamma\;</math> = The [[slope]] of the [[path loss]] curve. Unit: decibels per decade
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| :''d'' = The [[distance]] on which the [[path loss]] is to be calculated.
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| :''F''<sub>A</sub> = Adjustment factor.
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| ===Calculation of reference path loss===
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| The reference [[path loss]] is usually computed along a 1 km or 1 mile link. Any other suitable length of path can be chosen based on the applications.
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| <math>L_0 \; = \; G_B \; + \; G_M \; + \; 20 \; (\log \lambda \; - \; \log d) \; - \; 22 </math> | |
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| where,
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| :''G''<sub>B</sub> = [[Base station]] [[Antenna (radio)|antenna]] [[gain]]. Unit: decibel with respect to [[isotropic antenna]] (dBi)
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| :<math>\lambda</math> = [[Wavelength]]. Unit: meter (m).
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| :''G''<sub>M</sub> = [[Mobile station]] antenna gain. Unit: Decibel with respect to isotropic antenna (dBi).
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| ===Calculation of adjustment factors===
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| The adjustment factor is calculated as:
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| <math>F_A \; = \; F_{BH} \; F_{BG} \; F_{MH} \; F_{MG} \; F_{F} </math>
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| where,
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| :''F''<sub>BH</sub> = Base station antenna height correction factor.
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| :''F''<sub>BG</sub> = Base station antenna gain correction factor.
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| :''F''<sub>MH</sub> = Mobile station antenna height correction factor.
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| :''F''<sub>MG</sub> = Mobile station antenna gain correction factor.
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| :''F''<sub>F</sub> = Frequency correction factor
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| ===The base station antenna height correction factor===
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| <math>F_{BH} \; = \; \left( \; \frac{h_B}{30.48} \; \right)^2</math>
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| where,
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| :''h''<sub>B</sub> = Base station antenna height. Unit: meter (m). | |
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| ''or''
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| <math>F_{BH} \; = \; \left( \; \frac{h_B}{100} \; \right)^2</math>
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| where,
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| :''h''<sub>B</sub> = Base station antenna height. Unit: foot (ft).
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| ===The base station antenna gain correction factor===
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| <math>F_{BG} \; = \; \frac{G_B}{4}</math>
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| where,
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| :''G<sub>B</sub> = Base station antenna gain. Unit: decibel with respect to [[Dipole antenna|half wave dipole antenna]] (dBd)
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| === The mobile station antenna height correction factor ===
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| <math>F_{MH}\;=\;\begin{cases}\;\;\frac{h_M} {3} \;\;\;\;\mbox{ if, } h_M > 3 \\ \Big( \frac {h_M}{3} \Big)^2 \mbox{ if, }h_M \le 3 \end{cases}</math>
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| where,
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| :''h<sub>M</sub> = Mobile station antenna height. Unit: meter(m).
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| ===The mobile antenna gain correction factor===
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| <math>F_{MG} \; = \; G_M</math>
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| where,
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| :''G<sub>M</sub> = Mobile station antenna gain. Unit: Decibel with respect to half wave dipole antenna (dBd).
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| ===The frequency correction factor===
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| <math>F_F\;=\;\big( \frac{f}{900} \big)^{-n} \mbox{ for } 2 < n < 3</math>
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| where,
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| :''f'' = Frequency. Unit: [[megahertz]] (MHz)
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| ==See also==
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| * [[Hata Model for Urban Areas]]
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| * [[Hata Model for Suburban Areas]]
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| * [[Hata Model for Open Areas]]
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| * [[Okumura Model for Urban Areas]]
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| * [[Cost 231 Model|COST 231 Model]]
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| * [[Young Model]]
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| * [[Point to Point Lee Model]]
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| [[Category:Radio frequency propagation]]
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The name of the author is Luther. I presently live in Alabama. The job I've been occupying for years is a bookkeeper but I've already utilized for another one. What she enjoys performing is to play croquet but she hasn't produced a dime with it.
Also visit my homepage :: auto warranty (source for this article)