怎样寻找业余电台

BG5CEH

人类对无线电通信的认识是从电磁波开始的。当电流流经导体时，导体周围会产生磁场；当导体和磁力线发生相对切割运动时导体内会感生电流，这就是电磁感应。如果流经导体的电流大小、方向以及快的速度变化，导体周围的磁场大小方向也随之变化。变化的磁场在其周围又感生出同样变化着的电场，而这电场又会再一次感生出新的磁场……。这种迅速向四面八方扩散的交替变化着的磁场和电场的总和就是电磁场，磁场和电场每秒钟内周期变化的次数就是电磁波的频率。频率的基本单位是赫兹（Hz）。 人们进而发现，各种可见光、各种射线和上面所说的电磁波具有同样的性质，都是电磁波，只不过各自有着不同的频率。于是，人们把频率在3000GHz（详见表1-1说明）以下，不通过导线、电缆或人工波导等传输媒介，在空间辐射传播的电磁波定义为无线电波。无线电波和其他电磁波一样，在空间传播的速度是每秒30万公里。波速和频率（单位：Hz）的比值称为波长，单位是米（m）。 人们发现，在无线电波到达之处，导体又能从中感生出电流，而这个电流的大小、方向的变化规律和起初产生电磁场的电流的变化规律完全一致。也就是说，无线电波可以使信息（既初始电流的某种变化规律）通过空间传播实现远距离传递，这就是无线电通信。

[此贴子已经被作者于2006-10-5 14:02:02编辑过]

BG5CEH

<p><table cellspacing="0" cellpadding="0" width="532" border="0" style="WIDTH: 400pt; BORDER-COLLAPSE: collapse;"><tbody><tr height="26" style="HEIGHT: 19.5pt; mso-height-source: userset;"><td class="xl24" width="72" height="26" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; WIDTH: 54pt; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 19.5pt; BACKGROUND-COLOR: transparent;"><font size="3">段号</font></td><td class="xl25" width="110" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; WIDTH: 83pt; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">频段名称</font></td><td class="xl25" width="111" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; WIDTH: 83pt; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">频率范围</font></td><td class="xl37" width="117" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; WIDTH: 88pt; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">波段名称</font></td><td class="xl25" width="122" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; WIDTH: 92pt; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">波长范围</font></td></tr><tr height="22" style="HEIGHT: 16.5pt;"><td class="xl26" height="22" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 16.5pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">1</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">极低频</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">3~30Hz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">极长波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">100×10</font><font class="font7">⁶</font><font class="font5">～10</font><font class="font6" face="Times New Roman">×10</font><font class="font7">⁶</font><font class="font5">m</font></font></td></tr><tr height="22" style="HEIGHT: 16.5pt;"><td class="xl26" height="22" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 16.5pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">2</font></td><td class="xl29" style="BORDER-LEFT-COLOR: #eceae6; BORDER-BOTTOM-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BACKGROUND-COLOR: transparent; BORDER-RIGHT-COLOR: #eceae6;"><font size="3">超低频</font></td><td class="xl30" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">30~300Hz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">超长波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10×10</font><font class="font7">⁶</font><font class="font5">～1</font></font></td></tr></tbody></table></p>

BG5CEH

<table cellspacing="0" cellpadding="0" width="532" border="0" style="WIDTH: 400pt; BORDER-COLLAPSE: collapse;"><tbody><tr height="22" style="HEIGHT: 16.5pt;"><td class="xl26" height="22" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 16.5pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">3</font></td><td class="xl31" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">特低频</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">300~3000Hz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">特长波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">100×10</font><font class="font7">⁴</font><font class="font5">～10</font><font class="font6" face="Times New Roman">×10</font><font class="font7">⁴</font><font class="font5">m</font></font></td></tr><tr height="22" style="HEIGHT: 16.5pt;"><td class="xl26" height="22" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 16.5pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">4</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">甚低频（<font class="font6" face="Times New Roman">VLF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">3~30kHz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">甚长波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10×10</font><font class="font7">⁴</font><font class="font5">～1</font><font class="font6" face="Times New Roman">×10</font><font class="font7">⁴</font><font class="font5">m</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">5</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">低频（<font class="font6" face="Times New Roman">LF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">30~300kHz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">长波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10</font><font class="font5">～</font><font class="font6" face="Times New Roman">1km</font></font></td></tr></tbody></table>

BG5CEH

<table cellspacing="0" cellpadding="0" width="532" border="0" style="WIDTH: 400pt; BORDER-COLLAPSE: collapse;"><tbody><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">6</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">中频（<font class="font6" face="Times New Roman">MF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">300~3000kHz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">中波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">1000</font><font class="font5">～</font><font class="font6" face="Times New Roman">100m</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">7</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">高频（<font class="font6" face="Times New Roman">HF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">3~30MHz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">短波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">100</font><font class="font5">～</font><font class="font6" face="Times New Roman">10m</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">8</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">甚高频（<font class="font6" face="Times New Roman">VHF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">30~300MHz</font></td><td class="xl32" colspan="2" style="BORDER-RIGHT: black 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT-COLOR: windowtext; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">米波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10</font><font class="font5">～</font><font class="font6" face="Times New Roman">1m</font></font></td></tr></tbody></table>

BG5CEH

<table cellspacing="0" cellpadding="0" width="532" border="0" style="WIDTH: 400pt; BORDER-COLLAPSE: collapse;"><tbody><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">9</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">特高频（<font class="font6" face="Times New Roman">UHF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">300~3000MHz</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">分米波</font></td><td class="xl34" rowspan="4" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: windowtext; BORDER-BOTTOM: black 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">微波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">1</font><font class="font5">～</font><font class="font6" face="Times New Roman">0.1m</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">10</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">超高频（<font class="font6" face="Times New Roman">SHF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">3~30GHz</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">厘米波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10</font><font class="font5">～</font><font class="font6" face="Times New Roman">1cm</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">11</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">极高频（<font class="font6" face="Times New Roman">EHF</font><font class="font5">）</font></font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">30~300GHz</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">毫米波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">10</font><font class="font5">～</font><font class="font6" face="Times New Roman">1mm</font></font></td></tr><tr height="21" style="HEIGHT: 15.75pt;"><td class="xl26" height="21" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 15.75pt; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">12</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">至高频</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font face="Times New Roman" size="3">300~3000GHz</font></td><td class="xl27" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3">丝米波</font></td><td class="xl28" style="BORDER-RIGHT: windowtext 1pt solid; BORDER-LEFT-COLOR: #eceae6; BORDER-TOP-COLOR: #eceae6; BORDER-BOTTOM: windowtext 1pt solid; BACKGROUND-COLOR: transparent;"><font size="3"><font face="Times New Roman">1</font><font class="font5">～</font><font class="font6" face="Times New Roman">0.1mm</font></font></td></tr></tbody></table>

BG5CEH

<p>说明：（1）频率基本单位为赫兹（Hz），简称赫。1000赫等于1千赫（kHz），1000兆等于1吉赫（GHz）。<br/>　　　（2）频率范围均含上限，不含下限。</p>