Преглед на кода на DBm

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'''dBm''' („ди-би-ем“ или децибел-миливат), понякога също '''dB<sub>mW</sub>''', е съкращение от съотношение на [[мощност]]и в [[децибел]]и (dB), на измерената мощност към един [[ват|миливат]] (mW). Тази измервателна единица се използва в [[радио]], [[микровълни|микровълновите]] и [[оптична система|оптични]] [[мрежи]], като удобна мярка за абсолютната мощност, поради способността си да изразява много големи и много малки стойности в кратка форма.

За преобразуване на произволна мощност '''P''' (във '''[[W]]'''), като '''х''' (в '''dBm'''), или обратно, могат да бъдат използвани следните уравнения:

:<math>x, dBm = 10 \log_{10}\frac{P,W}{1mW} = 10 \lg (1000P) = 10 \lg P + 30</math>

и

:<math>P, W = \frac{10^{\frac{x,dBm}{10}}}{1000} = 10^{\frac{x,dBm-30}{10}}</math>

където ''P, W'' е мощността в W, а ''x, dBm'' е отношението на мощностите в dBm.

Например: 0 dBm се равняват на 1 mW.

<table border="1" cellpadding="0" cellspacing="0">
 <tr>
 <td width="50px" align="center"> dBm</td>
 <td width="150px" align="center">W</td>
 <td width="50px" align="center"> dBm</td>
 <td width="150px" align="center">W</td>
 <td width="50px" align="center"> dBm</td>
 <td width="150px" align="center">W</td>
 <td width="50px" align="center"> dBm</td>
 <td width="150px" align="center">W</td>
 </tr>
 <tr>
 <td align="center">0</td>
 <td align="center">1 mW</td>
 <td align="center">16</td>
 <td align="center">40 mW</td>
 <td align="center">32</td>
 <td align="center">1,6 W</td>
 <td align="center">50</td>
 <td align="center">100 W</td>
 </tr>
 <tr>
 <td align="center">1</td>
 <td align="center">1,3 mW</td>
 <td align="center">17</td>
 <td align="center">50 mW</td>
 <td align="center">33</td>
 <td align="center">2 W</td>
 <td align="center">54</td>
 <td align="center">250 W</td>
 </tr>
 <tr>
 <td align="center">2</td>
 <td align="center">1,6 mW</td>
 <td align="center">18</td>
 <td align="center">63 mW</td>
 <td align="center">34</td>
 <td align="center">2,5 W</td>
 <td align="center">57</td>
 <td align="center">500 W</td>
 </tr>
 <tr>
 <td align="center">3</td>
 <td align="center">2 mW</td>
 <td align="center">19</td>
 <td align="center">79 mW</td>
 <td align="center">35</td>
 <td align="center">3,2 W</td>
 <td align="center">60</td>
 <td align="center">1000 W</td>
 </tr>
 <tr>
 <td align="center">4</td>
 <td align="center">2,5 mW</td>
 <td align="center">20</td>
 <td align="center">100 mW</td>
 <td align="center">36</td>
 <td align="center">4 W</td>
 <td align="center">64</td>
 <td align="center">2500 W</td>
 </tr>
 <tr>
 <td align="center">5</td>
 <td align="center">3,2 mW</td>
 <td align="center">21</td>
 <td align="center">126 mW</td>
 <td align="center">37</td>
 <td align="center">5 W </td>
 <td align="center">67</td>
 <td align="center">5000 W</td>
 </tr>
 <tr>
 <td align="center">6 </td>
 <td align="center">4 mW </td>
 <td align="center">22 </td>
 <td align="center">158 mW </td>
 <td align="center">38 </td>
 <td align="center">6,3 W </td>
 <td align="center">70</td>
 <td align="center">10 000 W</td>
 </tr>
 <tr>
 <td align="center">7 </td>
 <td align="center">5 mW </td>
 <td align="center">23 </td>
 <td align="center">200 mW </td>
 <td align="center">39 </td>
 <td align="center">8 W </td>
 <td align="center">74</td>
 <td align="center">25 000 W</td>
 </tr>
 <tr>
 <td align="center">8 </td>
 <td align="center">6 mW </td>
 <td align="center">24 </td>
 <td align="center">250 mW </td>
 <td align="center">40 </td>
 <td align="center">10 W </td>
 <td align="center">77</td>
 <td align="center">50 000 W</td>
 </tr>
 <tr>
 <td align="center">9 </td>
 <td align="center">8 mW </td>
 <td align="center">25 </td>
 <td align="center">316 mW </td>
 <td align="center">41 </td>
 <td align="center">13 W </td>
 <td align="center">80</td>
 <td align="center">100 000 W</td>
 </tr>
 <tr>
 <td align="center">10 </td>
 <td align="center">10 mW </td>
 <td align="center">26 </td>
 <td align="center">398 mW </td>
 <td align="center">42 </td>
 <td align="center">16 W </td>
 <td align="center">84</td>
 <td align="center">250 000 W</td>
 </tr>
 <tr>
 <td align="center">11 </td>
 <td align="center">13 mW </td>
 <td align="center">27 </td>
 <td align="center">500 mW </td>
 <td align="center">43 </td>
 <td align="center">20 W </td>
 <td align="center">87</td>
 <td align="center">500 000 W</td>
 </tr>
 <tr>
 <td align="center">12 </td>
 <td align="center">16 mW </td>
 <td align="center">28 </td>
 <td align="center">630 mW </td>
 <td align="center">44 </td>
 <td align="center">25 W </td>
 <td align="center"></td>
 <td align="center"></td>
 </tr>
 <tr>
 <td align="center">13 </td>
 <td align="center">20 mW </td>
 <td align="center">29 </td>
 <td align="center">800 mW </td>
 <td align="center">45 </td>
 <td align="center">32 W </td>
 <td align="center"></td>
 <td align="center"></td>
 </tr>
 <tr>
 <td align="center">14 </td>
 <td align="center">25 mW </td>
 <td align="center">30 </td>
 <td align="center">1 W </td>
 <td align="center">46 </td>
 <td align="center">40 W </td>
 <td align="center"></td>
 <td align="center"></td>
 </tr>
 <tr>
 <td align="center">15 </td>
 <td align="center">32 mW </td>
 <td align="center">31 </td>
 <td align="center">1,3 W </td>
 <td align="center">47 </td>
 <td align="center">50 W </td>
 <td align="center"></td>
 <td align="center"></td>
 </tr>
</table>

== Вижте също ==
* [[Децибел]]
* [[dBW]]

[[Категория:Единици за измерване]]