車載通訊系統基頻處理平台研究

The Study of the Baseband Processing Platform for Dedicated Short Range Communication System

周俊祥(Chung-Hsiang Chou)

指導教授 ： 馬杰

元智大學/工程學院/通訊工程學系/碩士(2004年)

摘要

車載通訊(Dedicated Short Range Communications，DSRC)系統為路側對車輛或車輛對車輛之無線通訊系統，提供短、中程通訊服務。DSRC 系統具備高移動性、高資料率、低傳輸延遲與小通訊涵蓋區之特性，應用範圍非常廣泛，為智慧型運輸系統(Intelligent Transportation System, ITS)之重要核心技術。本篇論文主要根據ASTM2213-03 (802.11p)標準進行DSRC基頻信號處理之分析、模擬與雛型功能實現研究。
本文主要研究項目為：建立一時變衰減通道模型；設計在時變衰減通道環境中可適用之接收機同步機制(封包偵測、時序同步、載波頻率同步)；利用最小均方(Least Square, LS)法則以領航信號(Pilot Signal)進行通道估測與補償，解決了時變衰減通道對DSRC接收機效能造成的影響，使其符合規格書所訂定之規範；最後在單處理器架構下，以TMS320C6701信號處理平台完成DSRC基頻接收機之實現，並產生時變通道正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)調變信號進行測試。

關鍵字

車載通訊系統,時變衰減通道,最小均方法則,領航信號等化器

並列摘要

The dedicated short range communications (DSRC) system is a high mobility broadband wireless communications system, which can provide short and medium range communication services. The DSRC system has the features of high mobility, high data rate, low transmission latency, and small communication coverage area. The prototype of the DSRC baseband signal processing is analyzed, simulated, and realized according to ASTM E2213-03 standard.
The major research items of the thesis include: (1) constructing a time-varying fading channel model; (2) designing a receiver synchronization mechanism for the DSRC system to operate in the time-varying channels; (3) realizing the DSRC baseband processing with TMS320C6701 DSP platform, which is tested by using the time-varying orthogonal frequency division multiplexing (OFDM) modulation signals.

並列關鍵字

DSRC, time-varient fading channel, least square method,and pilot based equalizer

參考文獻

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