查詢結果分析
來源資料
頁籤選單縮合
題 名 | Capacity Evaluation of a Modern TDMA System in City Street Microcells=現代分時多工系統在市區街道微區之通信容量評估 |
---|---|
作 者 | 李金椿; | 書刊名 | 中正嶺學報 |
卷 期 | 24:2 1996.01[民85.01] |
頁 次 | 頁177-190 |
分類號 | 448.6 |
關鍵詞 | 分時多工; 微區網行動無線電; 個人通信網路; 訊號干擾比; Time division multiple access; Microcells; Personal communication network; Signal-to-interference ratio; |
語 文 | 英文(English) |
中文摘要 | 本文旨在評估部署於市區直線性街道中之十字形及長方形微區的個人通信網路之 通信容量,我們以「 channels/microcell/MHz 」為標準評估一擁有功率控制,頻率跳躍, 及不連續發射之現代分時多工( Time Division Multiple Access )系統, 當語音活動因 數為 1,1/2,3/8 時, 此具有完美功率控制的現代分時多工系統可分別提供 20,23,24.2 dB 之信號干擾比, 相對於區群數為二的十字形與區群數為四的長方形微區分別可提供 18, 9 channels/microcell/MHz 之通信容量, 其因不完美功率控制所造成信號干擾比之降低對分 時多工系統容量並無顯著的影響,雖然十字形微區的之通信容量為在長方形微區的兩倍,但 是在市區街道中若無線電傳播無法完全為建築物所阻擋,那麼長方形微區網之部署方式較十 字形微區網健全, 在受阻概率( blocking probability )為 2 %及街道寬度 10 米狀況 下,十字形及長方形微區兩者均可提供 1085 Erlang/MHz/km �握妊q信交通量,不過長方形 微區的部署所需要的基地電臺數為十字形微區的兩倍。 |
英文摘要 | A PCN using cross-shape and rectangular-shape microcells is deployed in a city area having rectilinear streets. The capacity of a modern time division multiple access (TDMA) system having power control, frequency hopping, and discontinuous transmission in these city street microcells is evaluated in terms of number of channels/microcell/MHz. For a voice activity factor of 1, 1/2, and 3/8, the perfect power controlled TDMA system can provide a signal-to-interference ratio (SIR) of 20, 23, and 24.2 dB, respectively, corresponding to a capacity of 18 and 9 channels/microcell/MHz for the cross-shape and the rectangular-shape microcells having two and four microcells per cluster, respectively. The decrease in SIR due to imperfect power control has no significant effect on the TDMA system capacity. The cross-shape microcellular arrangement has a capacity that is twice that of the rectangular-shape microcellular version, but the rectangular-shape microcellular deployment is more robust in this city street environment if the radio transmissions are not perfectly blocked by the buildings. For a blocking probability of 2% and a street width of 10 meter, both the rectangular-shape and the cross-shape microcells can provide a teletraffic capacity of 1085 Erlang/MHz/km ��, while the number of BSs deployed in the rectangular-shape microcellular arrangement is twice that in the cross-shape microcellular arrangement for the same service area. |
本系統中英文摘要資訊取自各篇刊載內容。