行動電話IS-54之系統化設計方法

Abstract

IS-54-B是由美國EIA/TIA所制定的一種蜂巢式行動無線通訊標準, 在這標 準中定義了基地台(Base Station)與手機(Mobile Station)的無線電系 統(radio set)與呼叫過程(call processing)。在本論文中, 我們將以呼 叫過程為出發點, 針對IS-54-B行動無線通訊標準提出一套系統化的設計 方法。 在我們所提的方法是以"分割-合成"(divide-and-merge)為基本概 念, 在分割的同時採用階層式的設計觀念。我們將這一套系統設計的方法 分成三大步驟: 一、從系統規格中分割產生出成許多系統方塊(system blocks)。 在分析IS-54-B系統規格後, 針對所得的特性我們定義了分割 樹(GP tree), 它用來把呼叫過程的特性做一適當的對應, 然後針對這些 分割樹做分析重組成一些系統方塊樹, 另外定義通道單元(ChannelUnit) 架起分割樹間的聯繫, 最後合成產生一些系統方塊。再定義三種價值函 數(value function)用來判斷這些系統方塊的設計形式。二、提出一系統 模組去模擬所產生的系統方塊圖。在此, 我們在QNX作業系統下設計一基 地台模擬系統來驗證所提的設計方法。三、產生一可模仿原系統規格的系 統架構。 IS-54-B is a cellular mobile radio communication standard which is defined by EIA/TIA at April 1992. It specifies both radio-system parameters and callprocessing procedures between base stations and mobile stations. In this thesis, we propose a system design methodology for IS-54-B mobileradio communication standard. Both "divide-and-merge" and "hierarchy design"concepts are used. The proposed methodology, started with call processing specification", is consisted of three steps. First, the specification is partitioned into some sytem blocks. According to the result of call processing specification analysis, we define some notations to assist the generation of system block trees. Then the graph partition tree(GP tress) is defined. After the mapping between the call processingspecification and GP trees, five primitive functions are used to analyze andreconstruct our system blocks. We also define ChannelUnit to maintain communication between GP trees. And then three value functions are defined to give a decision level between hardware and software design. Secondly, a system model is developed to validate the early steps of the design process. A base station simulation system is implemented under QNX operating system. Thirdly, generating an architecture to emulate the initial specification.