IEEE 802.15.4 無線個人區域網路收發機之系統評估與數位基頻設計

Abstract

IEEE 802.15.4 標準制訂於2003年11月，主要針對於無線個人區域網路之應用而發展。由於此標準中所訂定之低資料傳輸率及低複雜度，其主要目的在於提供一個低成本以及低功率的短距離傳輸標準。Zigbee聯盟已經採用IEEE 802.15.4做為其裝置中介質存取控制層及實體層的標準。 在本論文中，我們將集中於此標準中2.4 GHz頻帶之系統。此標準採用直接序列展頻的技術，以對抗外在之干擾而達到較強健之傳輸效果。我們將在論文中討論適合於IEEE 802.15.4標準之收發機系統架構以及敘述直接序列展頻技術所需要的數位信號處理單元。 我們將根據系統架構，在安捷倫Advanced Design System (ADS)中建立一個系統模擬平台。這個平台將包括傳送機模型，通道模型以及接收機模型。在這些模型中，數位部分以及類比/射頻部分將被加以整合模擬。對於數位設計者而言，此平台可以用來將類比效應加以考慮。對於系統設計而言，此平台可以用來決定設計參數以及評估設計元件之表現。系統模擬平台的觀念在系統晶片的時代中將會相當有用，因為需要整合性的解決方案，系統的表現也將可以透過初步的系統整合模擬而得到。

IEEE 802.15.4 standard is defined in November 2003 for wireless personal area network (WPAN). With low data rate and low complexity defined in the standard, its main purpose is to provide low-cost, low-power, and short-distance transmission. Zigbee Alliance has already adopted IEEE 802.15.4 as the media access control (MAC) layer and the physical (PHY) layer of Zigbee devices. In this thesis, we will focus on the 2.4 GHz band of this standard. Direct sequence spread spectrum (DSSS) is used in this standard to provide more robust transmission against interference. We will discuss suitable architectures for IEEE 802.15.4 transceivers in this thesis. Digital signal processing units for the DSSS technique will also be addressed. A system simulation platform is established in Agilent Advanced Design System (ADS) according to system architectures. The platform includes transmitter models, channel models, and receiver models. In these models, digital parts and analog/RF parts will be composed together. For digital designers, the platform can be used to take analog effects into consideration together. For system designers, the platform can be used to determine design parameters and evaluate the performance of designed components. The concept of the simulation platform is useful in the era of SoC because integrated solutions are necessary and system performance can be obtained through first-order system co-simulation.