通信人家园

标题: [公告]无线接入网知识  [查看完整版帖子] [打印本页]
时间:  2007-9-7 15:25
作者: gofay     标题: [公告]无线接入网知识

<strong><font face="黑体" color="#ff0066" size="3">&nbsp;无线接入网</font></strong><font lang="ZH-CN" face="??ì?,SimSun"><font color="#ff0066" size="3">
                </font><p align="justify"><font color="#ff0066" size="3">&nbsp;&nbsp;&nbsp; 包括固定无线接入网（</font><font size="3"><font color="#ff0066"><font face="宋体, MS Song">FWA Fixed Wireless Access</font><font lang="ZH-CN" face="??ì?,SimSun">，为固定位置的用户服务，如电话机、传真机、计算机）和移动无线接入网（为位置在移动的用户服务，如手持式、传便携式、车载式）。是实现“</font><font face="宋体, MS Song">5W</font><font lang="ZH-CN" face="??ì?,SimSun">”（任何人</font><font face="宋体, MS Song">Whoever</font><font lang="ZH-CN" face="??ì?,SimSun">随时</font><font face="宋体, MS Song">Whenever</font><font lang="ZH-CN" face="??ì?,SimSun">随地</font><font face="宋体, MS Song">Whereever</font><font lang="ZH-CN" face="??ì?,SimSun">能同任何人</font><font face="宋体, MS Song">Whoever</font><font lang="ZH-CN" face="??ì?,SimSun">实现任何方式</font><font face="宋体, MS Song">Whatever</font><font lang="ZH-CN" face="??ì?,SimSun">）的重要保证，我国目前规定固定无线接入系统工作频段为</font><font face="宋体, MS Song">450Mhz</font><font lang="ZH-CN" face="??ì?,SimSun">、</font><font face="宋体, MS Song">800/900 MHz</font><font lang="ZH-CN" face="??ì?,SimSun">、</font><font face="宋体, MS Song">1.8/1.9G Mhz</font><font lang="ZH-CN" face="??ì?,SimSun">和</font><font face="宋体, MS Song">3G MHz</font><font lang="ZH-CN" face="??ì?,SimSun">。固定无线接入一般由用户终端设备（单用户或多用户单元）、提供系统与无线用户之间无线连接的基站、基站控制器和网管组成，是</font><font face="宋体, MS Song">STN</font><font lang="ZH-CN" face="??ì?,SimSun">的延伸，见图</font><font face="宋体, MS Song">2.2-2</font><font lang="ZH-CN" face="??ì?,SimSun">。</font></font></font></p></font><font size="3"><font color="#ff0066"><font face="宋体, MS Song">FWA Fixed Wireless Access</font><font lang="ZH-CN" face="??ì?,SimSun">，为固定位置的用户服务，如电话机、传真机、计算机）和移动无线接入网（为位置在移动的用户服务，如手持式、传便携式、车载式）。是实现“</font><font face="宋体, MS Song">5W</font><font lang="ZH-CN" face="??ì?,SimSun">”（任何人</font><font face="宋体, MS Song">Whoever</font><font lang="ZH-CN" face="??ì?,SimSun">随时</font><font face="宋体, MS Song">Whenever</font><font lang="ZH-CN" face="??ì?,SimSun">随地</font><font face="宋体, MS Song">Whereever</font><font lang="ZH-CN" face="??ì?,SimSun">能同任何人</font><font face="宋体, MS Song">Whoever</font><font lang="ZH-CN" face="??ì?,SimSun">实现任何方式</font><font face="宋体, MS Song">Whatever</font><font lang="ZH-CN" face="??ì?,SimSun">）的重要保证，我国目前规定固定无线接入系统工作频段为</font><font face="宋体, MS Song">450Mhz</font><font lang="ZH-CN" face="??ì?,SimSun">、</font><font face="宋体, MS Song">800/900 MHz</font><font lang="ZH-CN" face="??ì?,SimSun">、</font><font face="宋体, MS Song">1.8/1.9G Mhz</font><font lang="ZH-CN" face="??ì?,SimSun">和</font><font face="宋体, MS Song">3G MHz</font><font lang="ZH-CN" face="??ì?,SimSun">。固定无线接入一般由用户终端设备（单用户或多用户单元）、提供系统与无线用户之间无线连接的基站、基站控制器和网管组成，是</font><font face="宋体, MS Song">STN</font><font lang="ZH-CN" face="??ì?,SimSun">的延伸，见图</font><font face="宋体, MS Song">2.2-2</font><font lang="ZH-CN" face="??ì?,SimSun">。</font></font></font><p align="center"><font color="#ff0066" size="3"><img height="203" src="file:///D:/Documents%20and%20Settings/admin/Local%20Settings/Temp/Rar$EX01.250/中兴接入网培训.files/1-1-1.18.gif" width="470" border="0" alt=""/></font></p><p class="MsoNormal" style="TEXT-INDENT: 21pt; LINE-HEIGHT: 18pt; mso-line-height-rule: exactly; tab-stops: 23.0pt;"><font size="3"><font color="#ff0066"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">固定无线接入网又可称为</span><span lang="EN-US">FWA</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">（</span><span lang="EN-US">Fixed Wireless Access</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">）或</span><span lang="EN-US">WLL</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">（</span><span lang="EN-US">Wireless Local Loop</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">），其成熟的技术有模拟蜂窝技术（如</span><span lang="EN-US">AMPS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">TACS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">NMT</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">NAMTS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">等）、数字蜂窝技术（如</span><span lang="EN-US">GSM</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">DAMPS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">CDMA</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">等）、微蜂窝技术和数字无绳技术（如</span><span lang="EN-US">CT2</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">DECT</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">、</span><span lang="EN-US">HS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">等）、以及</span><span lang="EN-US">3.5GHz</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">频段的数字微波。</span><span lang="EN-US">800MHz-1 GHz</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">频段技术成熟，成本低，适合农村、山区和沙漠地区使用。</span><span lang="EN-US">1.8 GHz -3.5 GHz</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">频段频率高、衰减大、覆盖面积小、成本高，适于城市地区。</span></font></font></p><p class="MsoNormal" style="TEXT-INDENT: 21pt; LINE-HEIGHT: 18pt; mso-line-height-rule: exactly; tab-stops: 23.0pt;"><font size="3"><font color="#ff0066"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">一般把基站覆盖范围分三类：一是宏区（</span><span lang="EN-US">Macro Cell</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">），覆盖半径为</span><span lang="EN-US">5-55km</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">；二是微区（</span><span lang="EN-US">Micro Cell</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">），覆盖半径为</span><span lang="EN-US">0.5-5km</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">；三是微微区（</span><span lang="EN-US">ico Cell</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">），覆盖半径为</span><span lang="EN-US">50-500m</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">。</span></font></font></p><h3><a name="_Toc488770275"><font size="3"><font color="#ff0066"><span lang="EN-US">2.2.3</span><span lang="EN-US" style="FONT-WEIGHT: normal; FONT-SIZE: 7pt; FONT-STYLE: normal; FONT-FAMILY: Times New Roman; FONT-VARIANT: normal;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><span style="FONT-FAMILY: 黑体; mso-ascii-font-family: 'Times New Roman';">无绳通讯系统</span></font></font></a></h3><p class="MsoNormal" style="TEXT-INDENT: 21pt; LINE-HEIGHT: 18pt; mso-line-height-rule: exactly; tab-stops: 23.0pt;"><font size="3"><font color="#ff0066"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">无绳通讯属于无线移动的一种，与蜂窝移动不同的是它不涉及网络，第一代无绳通讯系统是家用无绳电话，模拟制式、单路、覆盖范围</span><span lang="EN-US">200</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">米，如</span><span lang="EN-US">CT1</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">。第一代无绳通讯系统基于数字技术，用于公网，只能呼出，不能呼入，只能传送电话，无切换功能，覆盖范围</span><span lang="EN-US">50-300</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">米，如</span><span lang="EN-US">CT2</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">。</span><span lang="EN-US">1992</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">年出现欧洲数字无绳通讯（</span><span lang="EN-US">DECT</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">）系统，可双向通信，</span><span lang="EN-US">1995</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">年日本推出</span><span lang="EN-US">HS</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">系统，用户达</span><span lang="EN-US">700</span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">万以上。</span></font></font></p><p class="MsoNormalIndent" style="MARGIN-BOTTOM: 12pt; TEXT-INDENT: 21pt; LINE-HEIGHT: 18pt; mso-line-height-rule: exactly; tab-stops: 23.0pt;"><font size="3"><font color="#ff0066"><span style="mso-ascii-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt;">几种数字无绳电话系统的主要性能、指标如下：</span><span lang="EN-US" style="FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt;"><p>
                                        </p></span></font></font></p><p align="center"><font color="#ff0066" size="3"></font></p><center><table cellspacing="1" cellpadding="7" width="601" border="1"><tbody><tr><td valign="top" width="22%" colspan="2"><font color="#ff0066">　</font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">CT2</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">CT2+</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">CT3</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">DECT</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">PHS</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">PACS</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">标准制定者</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">英国</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">北电</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">爱立信</font></p></font></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">ETSI</font></p></td><td valign="top" width="12%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">日本</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">美国</font></p></font></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun" color="#ff0066"><p align="center">使用频段</p></font><p align="center"><font color="#ff0066">MHz</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">864.1-868.1</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">994-948</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">862-870</font></p><p align="center"><font color="#ff0066"></font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">1880-1990</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">1895-1918</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">1850-1910</font></p><p align="center"><font color="#ff0066">1930-1990</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">频段间隔</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">100kHz</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">100kHz</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">1MHz</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">1.728MHz</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">300kHz</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">300kHz</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">载频数</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">40</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">40</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">8</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">11</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">77</font></p></td><td valign="top" width="13%"><font color="#ff0066">　</font></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">调制方式</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">FSK</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">FSK</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">GMSK</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">GMSK</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066"><font face="Symbol">p</font> /4QPSK</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066"><font face="Symbol">p</font> /4QPSK</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">传输方式</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDD</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDD</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDD</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">TDD</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">TDD</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDD</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">接入方式</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">FDMA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">FDMA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDMA</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">TDMA</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">TDMA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">TDMA</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">信道总数</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">40</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">40</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">64</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">132</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">308</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">1024</font></p></td></tr><tr><td valign="top" width="11%" rowspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">信道分配方式</font></p></font></td><td valign="top" width="11%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">话音</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">DCA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">DCA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">DCA</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">DCA</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">DCA</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">QSAFA</font></p></td></tr><tr><td valign="top" width="11%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">控制</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">随机</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">专用</font></p></font></td><td valign="top" width="13%"><font color="#ff0066">　</font></td><td valign="top" width="14%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">专用</font></p></font></td><td valign="top" width="12%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">专用</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">专用</font></p></font></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">话音</font></p><p align="center"><font color="#ff0066">编码</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">32kbit/s</font></p><p align="center"><font color="#ff0066">ADPCM</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">32kbit/s</font></p><p align="center"><font color="#ff0066">ADPCM</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">32kbit/s</font></p><p align="center"><font color="#ff0066">ADPCM</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">ADPCM</font></p><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">或</font><font face="宋体, MS Song" color="#ff0066">CVSDM</font></p></font><font face="宋体, MS Song" color="#ff0066">CVSDM</font></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">32kbit/s</font></p><p align="center"><font color="#ff0066">ADPCM</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">32kbit/s</font></p><p align="center"><font color="#ff0066">ADPCM</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">手机发射平均功率</font></p></font></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">10mW</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">10mW</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">80mW</font></p></td><td valign="top" width="14%"><p align="center"><font color="#ff0066">10mW</font></p></td><td valign="top" width="12%"><p align="center"><font color="#ff0066">10mW</font></p></td><td valign="top" width="13%"><p align="center"><font color="#ff0066">25mW</font></p></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">公共场所提供业务</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">单向寻呼</font></p><p align="center"><font color="#ff0066">单向</font><font face="宋体, MS Song" color="#ff0066">+</font><font lang="ZH-CN" face="??ì?,SimSun"><font color="#ff0066">寻呼</font><p align="center"><font color="#ff0066">双向</font><font color="#ff0066"><font face="宋体, MS Song">+</font><font lang="ZH-CN" face="??ì?,SimSun">寻呼</font></font></p></font></p></font><font face="宋体, MS Song" color="#ff0066">+</font><font lang="ZH-CN" face="??ì?,SimSun"><font color="#ff0066">寻呼</font><p align="center"><font color="#ff0066">双向</font><font color="#ff0066"><font face="宋体, MS Song">+</font><font lang="ZH-CN" face="??ì?,SimSun">寻呼</font></font></p></font><font color="#ff0066"><font face="宋体, MS Song">+</font><font lang="ZH-CN" face="??ì?,SimSun">寻呼</font></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">双向呼叫</font></p><p align="center"><font color="#ff0066">越区切换</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">双向呼叫</font></p><p align="center"><font color="#ff0066">越区切换</font></p></font></td><td valign="top" width="14%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">双向呼叫</font></p><p align="center"><font color="#ff0066">越区切换</font></p></font></td><td valign="top" width="12%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">双向呼叫</font></p><p align="center"><font color="#ff0066">越区切换</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">双向呼叫</font></p><p align="center"><font color="#ff0066">越区切换</font></p></font></td></tr><tr><td valign="top" width="22%" colspan="2"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">移动性</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">步行</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">步行</font></p></font></td><td valign="top" width="13%"><font color="#ff0066">　</font></td><td valign="top" width="14%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">步行</font></p></font></td><td valign="top" width="12%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">机动车速</font></p></font></td><td valign="top" width="13%"><font lang="ZH-CN" face="??ì?,SimSun"><p align="center"><font color="#ff0066">机动车速</font></p></font></td></tr></tbody></table></center><p align="justify"><font size="3"><font color="#ff0066">FSK<font lang="ZH-CN" face="??ì?,SimSun">频移键控</font> GMSK<font lang="ZH-CN" face="??ì?,SimSun">高斯滤波最小频移键控</font> CVSDM<font lang="ZH-CN" face="??ì?,SimSun">连续可变斜率增量调制</font></font></font></p><p align="justify"><font size="3"><font color="#ff0066">DCA<font lang="ZH-CN" face="??ì?,SimSun">动态频道分配</font> QSAFA<font lang="ZH-CN" face="??ì?,SimSun">非静态自动信道分配</font> TDD<font lang="ZH-CN" face="??ì?,SimSun">时分双工</font></font></font></p><p align="justify"><font size="3"><font color="#ff0066">ADPCM<font lang="ZH-CN" face="??ì?,SimSun">厂自适应差分脉码调制</font>
                                <font face="Symbol">p</font> /4QPSK <font face="Symbol">p</font> /4<font lang="ZH-CN" face="??ì?,SimSun" size="1">四相相移键控</font></font></font></p>
时间:  2007-9-8 01:31
作者: appazj

<p>嗯，了解了一点。</p>



通信人家园 (https://www.txrjy.com/) Powered by C114