- 经验
- 342
- 分贝
- 0
- 家园分
- 0
- 在线时间:
- 0 小时
- 最后登录:
- 2007-12-4
- 帖子:
- 56
- 精华:
- 0
- 注册时间:
- 2007-5-15
- UID:
- 161064
注册:2007-5-15
|
<p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span lang="EN-US"><font face="Times New Roman">GSM</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman';">系统信道分类</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span lang="EN-US"><font face="Times New Roman">1</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、业务信道(</span><span lang="EN-US"><font face="Times New Roman">TCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)传输话音和数据</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";"> 话音业务信道按速率的不同,可分为全速率话音业务信道(</span><span lang="EN-US"><font face="Times New Roman">TCH/FS</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)和半速率话音业务信道(</span><span lang="EN-US"><font face="Times New Roman">TCH/HS</font></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"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";"> 同样,数据业务信道按速率的不同,也分为全速率数据业务信道(如</span><span lang="EN-US"><font face="Times New Roman">TCH/F9.6</font></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"><font face="Times New Roman"> TCH/F4.8</font></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"><font face="Times New Roman">TCH/F2.4</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)和半速率数据业务信道(如</span><span lang="EN-US"><font face="Times New Roman"> TCH/H4.8,TCH/H2.4)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(这里的数字</span><span lang="EN-US"><font face="Times New Roman">9.6,4.8</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">和</span><span lang="EN-US"><font face="Times New Roman">2.4</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">表示数据速率,单位为</span><span lang="EN-US"><font face="Times New Roman">kb/s)</font></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"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span lang="EN-US"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、控制信道(</span><span lang="EN-US"><font face="Times New Roman">CCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)传输各种信令信息</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";"> 控制信道分为三类:</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">1</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)广播信息(</span><span lang="EN-US"><font face="Times New Roman">BCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)是一种</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">一点对多点</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">的单方向控制信道,用于基站向所有移动台广播公用信息。传输的内容是移动台入网和呼叫建立所需要的各种信息。其中又分为:</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、频率校正信道(</span><span lang="EN-US"><font face="Times New Roman">FCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传输供移动台校正其工作频率的信息;</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">B</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、同步信道(</span><span lang="EN-US"><font face="Times New Roman">SCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传输供移动台进行同步和对基站进行识别的信息;</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">C</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、广播控制信道(</span><span lang="EN-US"><font face="Times New Roman">BCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传输通用信息,用于移动台测量信号强度和识别小区标志等。</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)公共控制信道(</span><span lang="EN-US"><font face="Times New Roman">CCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)是一种</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">一点对多点</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">的双向控制信道,其用途是在呼叫接续阶段,传输链路连接所需要的控制信令与信息。其中又分为:</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、寻呼信道(</span><span lang="EN-US"><font face="Times New Roman"> CH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传输基站寻呼移动台的信息;</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">B</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、随机接入信道(</span><span lang="EN-US"><font face="Times New Roman">RACH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):移动台申请入网时,向基站发送入网请求信息;</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">C</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、准许接入信道(</span><span lang="EN-US"><font face="Times New Roman">AGCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):基站在呼叫接续开始时,向移动台发送分配专用控制</span><font face="Times New Roman">
<span lang="EN-US"><p></p></span></font></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">信道的信令。</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">3</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)专用控制信道(</span><span lang="EN-US"><font face="Times New Roman">DCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)是一种</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">点对点</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">的双向控制信道,其用途是在呼叫接续阶段和在通信进行当中,在移动台和基站之间传输必需的控制信息。其中又分为:</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、独立专用控制信道(</span><span lang="EN-US"><font face="Times New Roman">SDCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传输移动台和基站连接和信道分配的信令;</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">B</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、慢速辅助控制信道(</span><span lang="EN-US"><font face="Times New Roman">SACCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):在移动台和基站之间,周期地传输一些特定的信息,如功率调整、帧调整和测量数据等信息;</span><span lang="EN-US"><font face="Times New Roman">SACCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">是安排在业务信道和有关的控制信道中</span><span lang="EN-US"><font face="Times New Roman">,</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">以复接方式传输信息。安排在业务信道时,以</span><span lang="EN-US"><font face="Times New Roman">SACCH/T</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">表示,安排在控制信道时,以</span><span lang="EN-US"><font face="Times New Roman">SACCH/C</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">表示,</span><span lang="EN-US"><font face="Times New Roman">SACCH/</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">常与</span><span lang="EN-US"><font face="Times New Roman">SDCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">联合使用。</span><span lang="EN-US"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><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"><font face="Times New Roman">C</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">、快速辅助控制信道(</span><span lang="EN-US"><font face="Times New Roman">FACCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">):传送与</span><span lang="EN-US"><font face="Times New Roman">SDCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">相同的信息。使用时要中断业务信息(</span><span lang="EN-US"><font face="Times New Roman">4</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">帧),把</span><span lang="EN-US"><font face="Times New Roman">FACCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">插入,不过,只有在没有分配</span><span lang="EN-US"><font face="Times New Roman">SDCCH</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">的情况下,才使用这种控制信</span><font face="Times New Roman">
</font><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">道。这种控制信道的传输速率较快,每次占用</span><span lang="EN-US"><font face="Times New Roman">4</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">帧时间,约</span><span lang="EN-US"><font face="Times New Roman">18.5ms</font></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"><p></p></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">由此可见,</span><span lang="EN-US"><font face="Times New Roman">GSM</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">通信系统为了传输所需的各种信令,设置了多种专门的控制信道。这样做,除因为数字传输为设置多各逻辑信道提供了可能外,主要是为了增强系统的控制功能,也为了保证话音通信质量,在模拟蜂窝系统中,要在通话进行过程中,进行控制信息的传输,必须中断话音信息的传输(</span><span lang="EN-US"><font face="Times New Roman">100ms)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">,这就是所谓的</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">中断一猝发</span><span lang="EN-US"><font face="Times New Roman">"</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">的控制方式。</span></p>
|
|