衛星光通訊系統之設計與分析

Design and Analysis of Coherent Optical Satellite Communication Systems

林奕志(Yi- Chih Lin)

指導教授 ： 曹士林

元智大學/工程學院/電機工程學系/碩士(2002年)

摘要

本文提出衛星光通訊系統，是利用於發射端的信號源與本地震盪雷射，透過自動所頻迴路，產生一個微波參考訊號。在接收端則藉此微波參考訊號，與接收端的本地震盪雷射，經自動鎖頻迴路，將原始信號解調還原。在接收端加上兩個外差式雙濾波器，一顆本地振盪雷射，和一個光鎖頻迴路，濾出訊號源和微波參考頻率訊號，並利用微波參考頻率訊號鎖定訊號源。此衛星光通訊系統架構，不僅易於控制光訊號的穩定性，而且還可以抵抗氣候的變化。雷射光又可以承載大量的資料，對於需要傳輸大量資料的多媒體通訊而言，是十分需要的。此外，我們亦對於雙向衛星通訊系統進行系統效能評估，亦比較與單向衛星通訊系統之優劣比較，作為未來光衛星通訊系統改進之分析。

關鍵字

衛星 ； 同調光通訊

並列摘要

In this thesis, we propose optical satellite communication which produce an reference frequence(RF) note by baseband signal and local oscillator laser through the automatic frequency control(AFC) circuits in the transmitter. In the receiver station, the baseband signal extracted by the RF and local oscillator laser by the AFC. The transmitter includes a signal laser, a local oscillator laser and an AFC circuit. The receiver includes two dual-filter heterodyne receivers, a local oscillator laser and an AFC circuit. This scheme can filter out the RF signal and frequency reference note, separately. Our proposed optical heterodyne satellite communication system not only can eliminate the frequency drifting, but also can transmit signals in worse weather. Because laser can carry large data, in the future, it can provide large data and establish the network of high speed communication through satellite. In addition, we also analyze the efficiency to the duplex satellite communication system and the simplex satellite communication system better to improve optical satellite communication system in the future.

並列關鍵字

satellite ； coherent optical communication

參考文獻

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