【正文】 列，一旦系統(tǒng)出現(xiàn)空閑信道，系統(tǒng)控制器將按先來先服務的原則為呼叫申請指配信道。用戶按下PTT開關，系統(tǒng)就為其分配一條空閑話音信道；用戶釋放PTT開關，系統(tǒng)立即釋放所占用的信道，該信道又可被再分配。2 術語(trunking munication system)指由多個用戶共用一組無線信道，并動態(tài)地使用這些信道的通信系統(tǒng)，主要用于調度通信。，未經(jīng)鑒定合格的設備不得在工程中使用。，充分考慮使用、維護及施工的要求，確保通信質量，做到技術先進，經(jīng)濟合理、安全可靠。中華人民共和國郵電部一九九七年二月十四日目 次1總則 ............................................................................................................12術語 ............................................................................................................23設計要求及服務質量指標 ........................................................................4 ...............................................................................................................4 .......................................................................................................4 ...............................................................................................................5 ...............................................................................................................64網(wǎng)路設計 ....................................................................................................8 ...............................................................................................................8 .............................................................................................10 .............................................................................................................115無線覆蓋區(qū)設計 ......................................................................................146頻率配置及復用 ......................................................................................16 .............................................................................................................16 .............................................................................................................167集群通信網(wǎng)接入有線電話網(wǎng)的方式 ......................................................188中繼線路、信令方式及摟口要求 ..........................................................20 .............................................................................................................20 .............................................................................................................20 .............................................................................................................219編號與計費 ..............................................................................................22 .............................................................................................................22 .....................................................................................................................2210設備選型 ................................................................................................2411站址選擇 ................................................................................................25 ...........................................................................................................25 ...................................................................................................................2512局站設計要求 ........................................................................................27 ...........................................................................................................2饋線及天線塔 .......................................................................................29 ...........................................................................................................30 ...........................................................................................................32附錄A800MHZ頻段的頻道分組 ..............................................................33附錄B本規(guī)定用詞說明 .............................................................................35附加說明 ....................................................................................................361總則 ..........................................................................................................383設計要求及服務質量指標 ......................................................................394網(wǎng)路設計 ..................................................................................................405 無線覆蓋區(qū)設計 ...................................................................................416頻率配置及復用 ......................................................................................427集群通信網(wǎng)接入有線電話網(wǎng)的方式 ......................................................438中繼線路、信令方式及接入要求 ..........................................................449編號與計費 ..............................................................................................4510設備選型 ................................................................................................4611站址選擇 ................................................................................................4712局站設計要求 ........................................................................................481 總